This page is about the stock Saurischian dinosaurs. Saurischian ("lizard-hipped" dinosaurs) included both the Theropods, the bipedal usually carnivorous dinosaurs which gave birth to true birds, and the Sauropods, the quadrupedal herbivorous dinosaurs with long necks that got extinct 66 mya in the Mass Extinction. Both lineages arose in the Triassic. Some kinds are, or were, uncertain if really belonged to the Saurischians, and the group itself is debated: some think (or have thought in the past) that theropods, or alternatively sauropods, were actually closer to Ornithischians than to the other subgroup of Saurischians.
Bipedal Meat-Eaters (usually)
Most dinosaurs were herbivorous or omnivorous; the Theropod group contains all the carnivorous dinosaurs. Some of them were very small, while the biggest weighed as much as an elephant or a bit more, and were taller and much longer than them. Their legs were birdlike in structure; their feet had three main toes and usually a smaller reversed forth toe. They were all bipedal except for the most derived ones like Spinosaurus; some had only tiny rudimentary forelimbs, like the tyrannosaurids. Theropods are the only group of dinosaurs that has living members today, since they included the common ancestor of birds. Some close-to-bird theropods became omnivores and sometimes herbivores; the group includes the only toothless non-bird-dinosaurs. Many theropods are now known to have been feathered, but in films they are usually shown with lizard-like scales, while documentaries tend to be a bit wonky on the coverings of their theropods.
The King of the Cretaceous: Tyrannosaurus rex ***
Lived in western North America, between Alberta and Utah, and possibly as far south as Texas, 68-66 mya at the very end of the Age of Dinosaurs. Other tyrannosaurs lived in Asia in the same period, and other members of the tyrannosaurid family lived slightly earlier, still within the Late Cretaceous Period, in North America. Asian remains attributed to T. rex are fragmentary and almost certainly didn't belong to it. Together with Triceratops and few others, Tyrannosaurus was one of the rare dinosaurs that was directly led to extinction by the asteroid/comet collision at the end of the Mesozoic Era.
T. rex was discovered by Barnum Brown shortly before the start of the 20th century, and described by Henry Fairfield Osborn in 1905. Since then, it has been a hit with the audience and possibly the most famous dinosaur for almost a century. During this time depictions of the "rex" have changed from the heavy, fat-bellied giant with goose-like gait and flexible tail seen in Fantasia to the slender, running beast seen in Jurassic Park. We have long waited to see it, or at least its chicks, depicted with feathers - although later studies have seemingly concluded that large tyrannosaurids would have been primarily scaly (any feathering would have been in the dorsal region) - presumably having secondarily lost or at least reduced their feathers. Recently this idea has been seeping into pop-consciousness: thank you Dinosaur Revolution, Dinosaur Island (2014), Pokémon, Mighty Magiswords, Saurian, and Doraemon.
Despite only living for a couple of million years in a small part of the world, every visit to a dinosaur-populated time or place will have at least one T. rex appearing. This is for reasons better explained on the animal's own trope page. Yes, that's how big it is in media.
- Entry Time: 1905
- Trope Maker: Itself
Sickle-Feet: Deinonychus going by the name of Velociraptor ***
Raptors, or more formally dromaeosaurids, were bipedal carnivorous dinosaurs of the Cretaceous Period. They were small with long, thin tails and compact bodies. They were closely related to birds: their skeletal structure was bird-like, and since the late 1990s it has been proven they were also covered with pennaceous feathers.
The most distinctive feature, howewer, was the large "sickle claw" on their second toe. It was a very specialized tool, and has also been compared with the saber-toothed cats' fangs. The toe bearing it was very shortened and strong compared with the other two main toes. When walking and running dromaeosaurids kept their 2nd toe raised up to the ground level, so the whole weight of their body was substained by only two digits of each hindlimb. The sickle-toes were moved by powerful muscles and tendons; scientists think "raptors" were able to lower them when used as weapons, just like cats do with their retractable claws. How it was used is being still debated. For decades, dromaeosaurids were depicted as hunting and attacking herbivores much bigger than itself, e.g. the classic Deinonychus hunting Tenontosaurus or even the five-ton Iguanodon. Like a pack of wolves, dromaeosaurids were envisioned attack their prey en masse, using their powerful claws to rend and to climb atop the herbivore. Since around the Turn of the Millennium, dromaeosaurids have instead been suggested to have been mostly solitary hunters, taking prey the same size or larger than themselves, but leaving the very large ornithopods or sauropods alone.
In the early 20th century, two small dinosaurs were discovered and described as generic small predators. Both were from the Late Cretaceous. While the finds were incomplete and difficult to interpret, we now know the animals were about 6.5 ft/2 m long and weighed about 33 lb./15 kg. Dromaeosaurus albertensis ("Alberta's running lizard") lived in the Alberta region, while Velociraptor mongoliensis ("Mongolian swift robber") lived in Mongolia and northern China 75-71 mya. For half a century, they were sorted away and largely ignored. Then...
Deinonychus note ("terrible claw") was (re)discovered in 1964. It lived 115-108 mya in Early Cretaceous North America and was at the same time one of the largest and one of the earliest raptors, 11 ft/3.4 m long and weighing 160 lb/73 kg. Even though some illustrations showed it as tall as an adult man, it would actually only reach his hips if alive today. Some years later, more complete remains of Velociraptor were found, showing that it was similar to Deinonychus but even smaller: the weight of a large turkey.
Deinonychus antirrhopus was described by John Ostrom in 1969 in an influential monograph that kicked off the "Dinosaur Renaissance". After that, paleontologists, especially Ostrom's pupil Bob Bakker, began to debate if the traits ascribed to Deinonychus (agility, smartness, warm-bloodedness, social behavior) should be extended to all dromaeosaurids, or possibly to all theropods, or even to all dinosaurs. This debate continues still today.
In the 1980s, one paleontologist (Gregory Paul) claimed that Deinonychus and Velociraptor were actually the same genus and that the species Deinonychus antirrhopus should be renamed "Velociraptor antirrhopus"; author Michael Crichton picked up this idea, showing both Deinonychus and Velociraptor proper in his Jurassic Park novel as distinct species within one single genus, "Velociraptor". "Velociraptor antirrhopus", aka Deinonychus, is the main "raptor" in the story, while Velociraptor mongoliensis itself appears only in the shape of newborns. Being bigger and more menacing for humans, Deinonychus was the one chosen for the bad guy role, even though it's possible Crichton chose to name it Velociraptor just because he thought this name is cooler-sounding.
Works from before the 1970s never represent dromaeosaurids, simply because they were scientifically too obscure at the time. Significantly, between 1970 and the Jurassic Park mania in the 1990s, the most represented "raptor" (though not yet known by that term) in popular culture was the biggest known at the time, Deinonychus, while the less-impressive Velociraptor was unknown to laymen, not counting the antecedent dino-fans. For instance, see the franchise Dino-Riders, the novel Carnosaur and the subsequent film, the Rune Quest Borderlands tabletop RPG adventure, or even the Dutch metal-band named Deinonychus. It was Jurassic Park that apparently caused Velociraptor to displace Deinonychus as the stock sickle-clawed dino (documentary media started showing the "veloci" more often thanks to the film), and started the usage of "raptor" for dromaeosaurid in the mind of the public — prior to this, "raptor" was used only to indicate Noble Bird of Prey. There are several issues with the depiction of raptors in the film.
How can we really tell Deinonychus apart from Velociraptor? Other than their different size, this can simply be done by observing their skull. The Deinonychus head was relatively stocky, with a convex profile and the snout ending with a thin point; the Velociraptor head was narrower and more elongated, with a concave profile and a blunt snout. If you watch carefully the head of the Jurassic Park "raptors", you'll note it's modeled upon the robust skull of Deinonychus. This would demonstrate the latter is the actual animal people think when they think "Velociraptor". However, the JP Deinonychuses have also exagerrately fleshy lips and too large eyes compared with the more realistic portraits of the Deinonychus in dino-books; these two modifications actually make their heads looking like a cross between a Deinonychus and a Velociraptor. About Utahraptor, this one cannot have been the inspirer of the JP critters despite being the most similar to them if you count the overall size of the body, both because the Utahraptor's skull was not still found at the time apart from the very end of the snout, and because this dinosaur was found slightly after the production of the first movie. Utahraptor was first discovered in Utah at the same time that the name Velociraptor became popular thanks to the original film Jurassic Park, in the early Nineties. This animal was even larger and slightly older than Deinonychus, living 128-105 mya and being 23 ft/7 m long and as tall as a human. Its naming in year 1993 began an awesome case of science culture Ascended Fanon (or inverted Pop-Cultural Osmosis if you prefer): before Jurassic Park, no genus of dromaeosaurids except Velociraptor had the -raptor suffix to its name. Since the film, paleontologists started to use it for naming most new dromaeosaurids.
Despite the scantiness of its original remain, the discovery of Utahraptor was much reported in media as it incidentally matched the size of the oversized JP raptors, or rather, was even longer than they were. Many then reported the Utahraptor as "the most fearsome killing-machines of all times", capable of killing, in packs, the biggest sauropods and even of destroying entire dinosaur species. However, Walking with Dinosaurs was not so extreme, showing Utahraptor hunting successfully the relatively smaller Iguanodon in group not in Utah but in Europe for some reason. In the later Jurassic Fight Club it is seen battling alone the even smaller but more protected ankylosaurian Gastonia, this time loosing the fight. Sadly, both shows portray the animal featherless, with a wrong Deinonychus-like head, and even with backward-pointing hands. Utahraptor recently has proven to have been a different and more specialized animal than what is shown in the traditional depictions: new remains reveal it to have had stumpy arms, a short tail, short, robust legs and a unique dentition, similar to animals like Masiakasaurus. What exactly this new look entails for the behavior and ecology of Utahraptor, as of now, remains uncertain.
The genus of Asian dromeosaurid named Velociraptor was first-found in Asia in the 1920s together with the similarly-named Oviraptor; before the production of the first film of the franchise in 1993 the dinosaur was basically portrayed only in popular dinosaur books (unlike the already fictionally portrayed Deinonychus, see Dino-Riders for an example of Deinonychus from The '80s): but the proper Velociraptor was already frequent in docu-media before JP, mainly thanks to an exceptional and (rightly) still-today celebrated finding made in The '70s in Mongolia: a specimen of the animal dead while grabbing the small herbivorous ceratopsian Protoceratops with its limbs. The fossil of this specimen of velociraptor is also particularly complete, with a lying-down body, the tail held rigid and pointing backwards, the head unusually not curved backwards but forwards (averting the so-called death pose extremely common in other dinosaur fossil skeletons, expecially of theropods), the "hands" grasping the other dinosaur's head, and one of its pedal sickle-talons into the neck of its victim. So, in classic dino-illustrations, the dinosaur is very often shown battling a Protoceratops and dying clutched together with it in several manners: buried by a sandstorm, stuck in mud or in quicksands, falling from a cliff, etc. according to the artist. On the other hand, the iconic battle between the two animals has strangely yet to appear in films or stories and in TV programs (except for of course the documentaries, like the 1993 Planet of Dinosaurs).
Speaking of Misplaced Wildlife, you can expect any of these three dromaeosaurids to be placed in the same habitat as at least Tyrannosaurus and Triceratops. In reality, Deinonychus and Utahraptor were already extinct by the time T. rex came along and Velociraptor lived on the other side of the planetnote . However, this inaccuracy was vindicated somewhat by the discovery of Acheroraptor (described in 2013) and Dakotaraptor (described in 2015), which greatly resembled Velociraptor and Deinonychus respectively, and the latter was roughly the size of Utahraptor.
According to the researches of The New '10s, raptor hunting tactics did not involve high-speed pursuits or using the claws to disembowel prey. What they did involve, however, was a ridiculous amount of Nightmare Fuel. Dromaeosaurs could only run at about 45 miles/hour for the faster species (Deinonychus and Velociraptor) and 20 miles per hour for the larger, more robust Utahraptor (this is still faster than any human), but they had Super Reflexes and superb Combat Parkour skills, able to leap, flip, dodge, and accelerate with ease. They were good climbers, and their feathered wings probably helped them control their falls as well as muffling sound. The talons provided a near-unbreakable grip, and were used as grappling devices and stabbing weapons. Recent research into their eye sockets proved they had superb vision and were able to see very well in the dead of night, which was when they would use Jump Scare tactics to sneak up on unwary prey. Put together, they provide a picture of an agile, stealthy, powerful hunter stalking victims at night from the treetops, completely silent and invisible, before leaping in as Death from Above, dodging counterattacks using Combat Parkour, latching on with a formidable grip, and either stabbing the prey in the neck or pinning it down and eating it alive as it writhed in agony.
But as of 2020, it's generally believed that complex pack hunting would not have occurred in this group. Mob hunting, like that of modern day crocodiles and komodo dragons, is still a possibility, but the idea of raptors using intelligence and coordination to take down prey much bigger than themselves is more fiction than fact. Small raptors probably occupied a similar niche to animals like cats and foxes today- solitary hunters of small mice-sized mammals and reptiles- or even their close relatives, small birds.
- Entry Time: 1970s/1980s
- Trope Maker: The "Dinosaur Renaissance" and the works inspired from it. Specifically, Deinonychus in the 1980s Dino Riders and other works, Utahraptor in the 1990s Raptor Red (a scientific novel), and the true Velociraptor in the 2000s Disney's Dinosaur
The King of the Jurassic: Allosaurus ***
Allosaurus lived 155 to 150 million years ago in North America, with some fossils found in Europe and maybe Africa. Along with Tyrannosaurus, it has traditionally been the large carnivorous dinosaur. Allosaurus is the scientifically most well-known large theropod: dozens of specimens have been found so far in Western USA, including a veritable "graveyard" in the Cleveland-Lloyd Dinosaur Quarry (Utah). At the time, there was a swamp where the "graveyard" is today: Allosauruses were attracted by the carrion of giant herbivores and got stuck in the mud as well. Many young individuals are also known, but not nests or hatchlings.
First discovered in 1877 during the Bone Wars, Allosaurus literally means "other lizard" or "strange lizard", but Othniel Charles Marsh's article naming it gives no reason for the bland choice. The most well-known species is Allosaurus fragilis ("the other fragile lizard"); some fragmentary remains of unusually large size are often classified in separate genera (see Prehistoric Life). Some scanty fossils from Early Cretaceous Australia used to be classified as a small-sized late-surviving Allosaurus species, but were reclassified in 2009 as a totally different theropod, Australovenator. Even scantier remains were found in the USA before Allosaurus was officially described in 1877; they were labeled Antrodemus, but possibly belong to Allosaurus as well. If true, the former might become the valid name for this dinosaur (the name "Antrodemus" appears sometimes in old dinosaur books instead of "Allosaurus").
Allosaurus was the top predator in the Late Jurassic, sometimes referred as "the tyrannosaur of the Jurassic". Its hunting behavior is still uncertain: we're not sure if it was mainly a pack-hunter or a solitary ambush-predator. In documentaries and pop-books it usually appears as a pack-hunter capable of bringing down the biggest sauropods like Diplodocus, like in the memorable The Ballad of Big Al, Apatosaurus, or even Brachiosaurus. Alternatively, it is shown in a battle against the armored Stegosaurus (the Jurassic equivalent of the Tyrannosaurus-vs-Triceratops Cretaceous duel). All this might be Truth in Television since all these animals lived together in North America in the same period, but more probably Allosaurus more often hunted easier prey such as young sauropods, young stegosaurs, and ornithopods like Camptosaurus, because its jaws and teeth were less-powerful than those of the tyrannosaurs. There are stegosaur and sauropod fossils showing Allosaurus bite marks and Allosaurus fossils that show wounds created by stegosaur tails, showing that allosaurs could have been predators as powerful as the more evolved tyrannosaurs.
Allosaurus entered pop culture before Tyrannosaurus rex. After its description, it was briefly considered the "biggest land carnivore ever" together with Megalosaurus. In Conan Doyles The Lost World (1912) the two scientists encounter a giant carnivore, and argue about whether it is an Allosaurus or a Megalosaurus, maybe a reference to the then-recent Bone Wars. Soon afterward, both dinosaurs got overshadowed by the more impressive (and much cooler-named) Tyrannosaurus in pop-media, especially cinema. Allosaurus has somehow managed to survive the supremacy of the rex... automatically becoming its Poor Man's Substitute, as the two animals tend to be easily confused with each other in the public mind. However, Allosaurus is still probably the second-most-portrayed large theropod in popular culture after Tyrannosaurus. If a writer is telling a story set in the Jurassic period instead of the Cretaceous and wants to be accurate, 99% of the time, this is the predator they'll use.
Allosaurus is rather easy to distinguish from T. rex if watched carefully. It was generally smaller (the classic species was slightly shorter and about one half of the weight of a T. rex), had shorter legs, a longer tail, slimmer body, longer neck, narrower head, weaker lower jaw, smaller teeth, and a pair of "bosses" in front of its eyes (maybe covered in keratin in Real Life, making them like small "horns"). Above all, it had longer front arms with three clawed fingers rather than two. Sadly, all these differences tend to be glossed over in popular media. The fact that T. rex itself has often been depicted with long arms with three functional digits (e.g. in Disney's Fantasia) doesn't help, either.
Among the official Allosaurus appearances in cinema, the Ray Harryhausen ones are the most remembered. The allosaur is the go-to Big Bad of his movies, appearing in One Million Years BC and playing the role of Gwangi in The Valley of Gwangi. Ray's critters looked just like that of Fantasia, with the same mishmash of allosaur and tyrannosaur features (and with the same outdated erect body, serpentine tail and goose-gait); the only difference is that Harryhausen's theropods have Evil Eyebrows — this may be forgivable for some, considering the aforementioned eye bosses wich could have given to it a "fierce look" like an eagle.
Since The '90s, a handful of large theropods have started to filter into pop-consciousness, often after a single remarkable appearance in Movieland: Spinosaurus (Jurassic Park III), Giganotosaurus (Primeval), Carnotaurus (Disney's Dinosaur), Baryonyx (Ice Age 3: Dawn of the Dinosaurs), some non-rex tyrannosaurs (Albertosaurus, Gorgosaurus, Tarbosaurus), and Dilophosaurus (the original Jurassic Park, of course). Despite having often some cool traits, like crests, horns, claws, or sheer size, none of them has managed to replace T. rex as the "King Dinosaur" at least for now. Ceratosaurus entered pop-culture around the same time of T. rex and Allosaurus, while Megalosaurus entered it much earlier, in the XIX century.
Spiny-backed Water Colossus: Spinosaurus **
Lived in Northern Africa 112-97 mya, during the Cretaceous Period. At present, this is the biggest theropod; no other matches it in bulk, length and weight.
Spinosaurus aegyptiacus means "egyptian spiny lizard": it has always been one of the most recognizable theropods with its 7 ft/2.1 m-tall spines on its back. In the most common interpretation the spines form a "sail" similar to that of the non-dinosaur Dimetrodon. Some suggest that they instead supported a fleshy hump or a ridge, while others thought they came from another dinosaur altogether. A sail could have been useful as a thermoregulating device to prevent overheating and/or as a display tool (like Stegosaurus plates), and a ridge could have been for display, making the animal seem larger, as well as storing extra energy gained from the giant fish and other prey that Spinosaurus fed on.
Spinosaurus was first described in 1915 by a German paleontologist, but its remains were very scanty: its skull was incomplete, and we didn't have limb bones. The best spinosaur find was stored in a German museum, which was destroyed by accident during an aerial bombing in World War II. In older drawings Spinosaurus had a head and body like a generic "large theropod"; since the last XX century it has generally been accepted that its head was similar to a crocodile's. Due to the fragmentary nature of its remains, the actual overall size has been in debate; it was traditionally thought the same length and height of an average Tyrannosaurus (40 ft/12 m long and 20 ft/6 m high) but lighter-weighing (4 tons instead of 6 tons of the rex); but many paleontologists wanted to set the length at 50 ft/15 m. Lack of real evidence for this left T. rex with the official record size until the discovery of Giganotosaurus in the mid-1990s.
Meanwhile, the spinosaur remained an only-known-among-dino-lovers dinosaur. Then, in the year 2001... Jurassic Park III (which fans dont really like to talk about but was nonetheless popular) changed this situation in a blink. This film introduced the spinosaur to the audience as "bigger and badder" than a Tyrannosaurus rex, and easily capable of defeating the latter in a fight. This was the start of the Spinosaurus vs. T. rex trope in media.
Many dino-fans at the time complained that the JP spinosaur was oversized and altered to make it a sort of Pseudo-Rex thing. Then, new discoveries told us Spielberg wasn't totally wrong: Spinosaurus really was bigger than Tyrannosaurus rex, in fact larger than shown in the film. Not only that, it was indeed the biggest of the lot, and is still considered to be.
There has always been controversy regarding Spinosaurus diet and way-of-life: did it prey on fish like its smaller cousin Baryonyx (see below), or on giant herbivores like Tyrannosaurus did? Experts tended to prefer the first option at the time Jurassic Park III was produced, and this fostered even more criticism about the film portrayal as the Ultimate Superpredator. In The New '10s Spinosauruss lifestyle was generally believed to have been midway between these two extremes: an opportunist like a giant, clawed, saltwater crocodile, attacking other smaller dinosaurs when given the opportunity, as well as eating giant fish (mostly sharks and other fish the size of most dinosaurs) and possibly crocodiles, a feat requiring tremendous levels of strength, and using its size to steal kills from other predators. Experts were unsure about the latter, though: Carcharodontosaurus was specially adapted to big-game hunting and could open its jaws very wide to inflict severe slicing cuts, which could likely cause the spinosaur to bleed to death if the two fought. Spinosaurus large size would, however, have made it a hard target to bite for other predators.
But the surprise was already hidden in the Saharian rocks: in 2014, Spinosaurus received an almost-total makeover after new fossils were discovered there. In addition to tiny pores in its skull that might have enabled it to sense underwater prey (which was already known by then), Spinosaurus also had a relatively small pelvis and short hind legs with flat possibly webbed hind feet, among other adaptations for a semiaquatic lifestyle all in all showing a surprising degree of convergent evolution with the ancestors of modern whales. Unrelated to its amphibious makeover, its reconstruction also gives it a dip in the middle of its dorsal spines similar to that of its relative Ichthyovenator. It has been suggested that the hind limbs were scaled incorrectly but then the people who made the discoveries have responded putting these supposed corrections to doubt. Also, the tall spine on the sail might have actually been located further back on the body thus forming a more shallow and gradual version of the "classic" Spinosaurus sail note , although this too is debatable. Finally, it has been suggested that Spinosaurus held its neck vertically rather than horizontally. This would have shifted the center of gravity back and allow Spinosaurus to walk bipedally most likely similar to a duck: Spinosaurus' forelimbs and shoulders seem to lack the weight-bearing adaptations needed for quadrupedal movement.
Not all scientists were convinced, however, and a 2018 study has been released suggesting that, rather than being a full time swimmer, Spinosaurus spent most of its time wading along the shore and hunting fish in shallow water, more like a giant heron or stork than a crocodile. However, this study is not without a few issues, namely giving the tested Spinosaurus models with a more narrow torso due to basing it on reconstructions seen in lateral view.
Finally, a new fossil discovered in 2020 revealed that Spinosaurus had a paddle-shaped tail, demonstrating that, yes, it was truly aquatic. Given that it inhabited the tidal reaches of a brackish coastal swamp, Spinosaurus was arguably also the only marine non-avian dinosaur, which moved itself on land probably by walking on all fours and knuckle-walking on its hands like a modern giant anteater, to prevent its hand-claws to get consumed by the friction against the drysoil.
Now dino-lovers are waiting to see whether an ocean-going spinosaurid or another non-bird dinosaur will be discovered, with the oceans being the only place that (so far) true dinosaurs are not known to have conquered. NOTE: The picture above of Spinosaurus is not updated anymore due to all this recent Science Marches On.
Giant Predator of the South: Giganotosaurus *
Giganotosaurus (NOT "Gigantosaurus"; that name was used for an invalid sauropod) lived in Late Cretaceous South America 97 million years ago. A close relative of Allosaurus, it had a bigger head (6 ft/1.80 m long, even longer than a Tyrannosaurs) and a stockier build: its looks seems rather like a cross between an allosaur and a tyrannosaur incidentally, making the classic hybrid allo/tyranno so often seen in classic films (Fantasia, 1 Million B.C. ) a sort of Truth in Television.
Discovered in 1993 and officially described two years later, Giganotosaurus was celebrated as "the biggest predatory dinosaur ever," surpassing Tyrannosaurus and Spinosaurus: the largest specimen known of the former at the time (the famous Sue) was discovered a few years before — now the biggest known rex specimen is "Scotty", described in 2019. The "giga" remained the record-holder until new Spinosaurus fossils were discovered in the 2000s, and the re-examination of the descriptions of older finds reminded us that the "spino" was even larger, something already postulated but ignored for 80 years.
At the same time, re-examination of Giganotosaurus remains show an animal not much larger that Tyrannosaurus; the only advantage in length is due to a longer snout, and were the two animals placed side-by-side, they'd appear to be the same size. Its close relative Carcharodontosaurus (known since the first half of the 20th century in the form of teeth and some sparse bones, but rediscovered in 1995), got the same treatment of Giganotosaurus in the 1990s, but ultimately lost the struggle against it for widespread recognition; and both theropods ended up overshadowed in popular culture by Spinosaurus — hence the only star we've given here to Giganotosaurus.
Giganotosaurus remains one of the most powerful meat-eaters that ever lived, and has started to gain popularity. The fact that it could have possibly hunted some of the largest sauropods — aka those Brontosaurus relatives belonging to the Titanosaur subgroup, see the Sauropods section — means that it may become very popular in the future. If that doesn't sound cool enough, then consider that to do so, it would have had to be a pack hunter. Chased By Dinosaurs did a special on just how badass such a hunt would be, even though in the show the long-necked dinosaur that became prey was a juvenile. Though there isn't any evidence for pack behavior in Giganotosaurus, there might be for its closest relative, the nigh-identical Mapusaurus, which was the same length but had a slightly more slender frame. Carcharodontosaurus and Mapusaurus are both represented in Planet Dinosaur, a BBC docu made in 2011 considered the "heir" of the 1999 Walking With Dinosaurs, but both fail to hunt successfully the giant sauropods of their habitat (Paralititan and Argentinosaurus respectively).
Missed Moment of Glory: Carcharodontosaurus *
In 1995, an unexpected find deeply shook the paleontological world as well as the dino-fandom. The obscure-at-the-time Carcharodontosaurus saharicus ("Sahara's sharp-toothed lizard") has revealed not to be a midsized, unclassifiable theropod as always thought - it was originally considered a megalosaur, but others thought it was an allosaur, an intermediate form between allosaurs & tyrannosaurs, or even a relative of ornithomimosaurs or a completely unique theropod that returned to the seas! It was a much more badass animal, whose name (Carcharodon is also the genus name of the modern great white shark) has revealed stunningly apt. A predatory dinosaur even bigger than T. rex!
Obviously, popular media ballyhooed the discover a lot totally forgetting that some other giant theropods were already Tyrannosaurus rex contestants for the biggest title much before 1995!! Spinosaurus makes the most striking example, but there is also the obscure Epanterias, almost certainly just an overgrown Allosaurus; not to mention the giant birdlike Deinocheirus and Therizinosaurus. But the glory of Carcharodontosaurus didnt last a long time; merely one year later, it was surpassed by the just-discovered, almost-identical, only a bit bigger, Giganotosaurus carolinii. Our shark toothed dino was a quite unlucky dinosaur, really.
However, in the 2000s, Spinosaurus has in a sense done justice to the carcharodontosaur, taking in turn the popularity of Giganotosaurus out thanks to Jurassic Park III. The awesome thing is, in Real Life Carcharodontosaurus and Spinosaurus living together in Cretaceous Africa where today is Sahara, maybe contended the top-predator niche with each other, but also with the "giant croc" Sarcosuchus imperator. While Carcharodontosaurus was better-weaponed with huge jaws, Spinosaurus was more enormous-bodied and could have been even twice its weight. They were often considered the tiger and the grizzly bear of their time respectively, and it was often supposed that Spinosaurus sometimes chased away Carcharodontosaurus from their kills like modern bears do with big cats when they live side-by-side — at least, before recent research seem showing the spinosaur not to be a land-dweller but a quadrupedal aquatic animal with a finned tail. Maybe they never fought in real life, due to the very different habitats (shallow seas and dryland respectively), and is more probable that the spinosaur had more interactions with the 40 ft long "supercroc" Sarcosuchus.
When the carcharodontosaurus was still believed a smallish 20 ft long agile carnivore, before 1995, the rare times it appeared in media (even the dino-books used to show it very seldom at the time) it was typically described as an underdog predator compared with the more rex-sized spinosaur still imagined land-dwelling and long-legged, a bit like the medium-sized Ceratosaurus confronted with the giant Allosaurus in Jurassic North America.
- Entry Time: 2000s
- Trope Maker: Its role as the ultimate rival for Spinosaurus
Meat-loving, sprinting Bull: Carnotaurus *
Another South American theropod like Giganotosaurus, Carnotaurus (yes, "-taurus", not "-saurus")note lived in the Late Cretaceous in a younger age, 70 million years ago. Discovered in Argentina in 1985 by Jose Bonaparte (an argentinian scientist), it is known from a single specimen, but this was one of these things every paleontologist wishes to find: one of very few big theropods so far found with skin impressions. As these prints are from the whole right side of its body, Carnotaurus is one of the only large dinosaurs whose external look is known with a reasonable degree of certainty, together with the so-called "hadrosaur mummies" of Edmontosaurus. We don't know what was the coloration of the living Carnotaurus, however.
Our carnotaur has also revealed to be one of the strangest-looking dinosaurs known. Forelimbs even tinier than those of T. rex, sort of useless stubs with no true fingers (though three clawed fingers appear in many portrayals, and sometimes even a small Iguanodon-like thumbclaw for each hand) that contrast vividly with the long legs apt for high-speed runs note . Unusually shortened head (some compare it to a bulldog's). Above all, a couple of unique bull-like horns above the eyes which no other known theropod had, not even its closest relatives: Carnotaurus means "meat-(eating) bull". Finally, its skin was covered by rows of horny tubercles. The horns and the skin make Carnotaurus a quite dragon-looking dinosaur. Ironically, with its slender body, tiny forearms, and fragile lower jaws, it's hard to imagine how it could kill large prey in Real Life, especially if you think it doesn't come close to rivalling Tyrannosaurus or Giganotosaurus in size (it was only about 22 ft/7 m or so in length, while a big rex would be about 43 ft/13 m). A clue may come from the fact it could have been the fastest non-bird dinosaur ever discovered, perhaps being able to run at 75 miles per hour. It has been suggested it ran into prey at full speed with jaws open, using its head as a sledgehammer.
Carnotaurus has become somewhat popular since the Nineties thanks to its striking look. Its most remembered appearance is in the 2000 Disneys Dinosaur, where it's shown as an oversized, pseudo-rex villain. Here, the biggest carnotaur appears even larger than a spinosaur, able to lift an Iguanodon with its jaws, and fling it to death against a rock. In Real Life the 1-ton Carnotaurus was much smaller and weaker than the 5-ton Iguanodon, and lived several million years after the latter. Before that, it also showed up in Michael Crichton's second Jurassic Park book, where its size was portrayed more accurately, but to up the threat level, it was given (quite implausible) chameleon-style stealth abilities. Note that neither modern birds nor crocodilians can change their colors rapidly like chameleons do. Finally, it has recently made a cameo in 2018's Jurassic World: Fallen Kingdom.
Carnotaurus may be the responsible for the recent decline of the classic carnivore Ceratosaurus in media, as both dinosaurs had a similarly horned/tubercled look and the two dinos might be confused with each other, even though their look was rather different. But also note a bit of resemblance both in shape and in name between the carnotaur and a mythical critter, the Minotaur. This association may have at least subconsciously led to it becoming a go-to bad guy dinosaur.
Heavy-clawed, croc-mouthed Fisher: Baryonyx *
This is a cousin of Spinosaurus that lived in Europe in the Early Cretaceous, 130-125 mya, alongside Iguanodon. Discovered in 1983 in Southern England and named in 1986 by A. Charig & A. Milner, its find got massive media coverage at the time, to the point it was qualified by some as "the greatest European dino-find of the XX century"; in part because, being 30 ft/9 m long, Baryonyx was the largest and most complete European giant theropod, but mostly because it was very different from other dinosaurs known at the time, with its crocodile-like jaws lined with an incredible 96 teeth (T. rex and Allosaurus had no more than 75 teeth). The skull also shows similarities to that of the early Coelophysis and Dilophosaurus, ex. the undulating edge of the upper jaw: so, one scientist thought the baryonyx was a gigantic Cretaceous descendant of them. Others thought it was somewhat close to dromeosaurs, because of its very special forelimbs.
Baryonyx means "heavy claw" and the animal has been nicknamed Claws by the press (a reference to the famous film Jaws of 1975) because of its 10-inch/25-cm hook-like thumb-claws, bigger than the other two fingers on each hand. We don't know if Spinosaurus had these hook hands as well. Baryonyxs forelimbs were longer and stronger than in most other theropods, but the structure of the forefeet seems to preclude quadrupedal walking (contrary to what has traditionally been shown in illustrations); it is speculated, however, that Baryonyx might have fed by resting on its front legs on a riverbank and sweeping large fish such as the carp-like Lepidotes from the river with its powerful claw, a bit like grizzly bears do with salmon. We know for sure fish were included in its diet: scales of Lepidotes were found inside the ribcage of the original (and only sure) Baryonyx specimen, named B. walkeri from his first discoverer: an english amateur fossil collector, William Walker, who first found the isolated thumbclaw of the animal jutting from the rocks like a spur (only one claw was found). Alan Charig and Angela Milner then found the remaining incomplete skeleton, and described it officially three years after.
Baryonyx was the first discovered fish-eater among dinosaurs, and several traits scientists assigned to Spinosaurus were initially based on Baryonyx. Together, these dinosaurs (plus few others) form the spinosaurid family. However, "Claws" was quite different from Spinosaurus: it had no sail on its backnote , and was considerably smaller (10 m long and weighing 2 tons, like an Allosaurus). Its head was thinner with a small bump on its top, and gharial-like jaws with twice the teeth of most other theropods. Baryonyx was traditionally believed more aquatic than Spinosaurus: fish might have made a great part of its diet, possibly with occasional carrion and small land animals as a supplement. Its short hindlegs show it was not an especially fast runner; moreover, its blunt croc-like teeth and weak thin jaws probably prevented the "bary" to kill prey the size of a fully-grown Iguanodon in spite of the former's huge thumbclaws. Incidentally, Iguanodon too had oversized thumbnails, but they were almost-straight and not curved like the carnivore's.
Since the 1980s, Baryonyx has been one of the most frequently-portrayed large theropods in popular dino-books. On the other hand, it has long been ignored in Fictionland and even most TV documentaries. It should have appeared in Walking with Dinosaurs as the predator of Iguanodon, but was finally substituted by the misplaced giant dromeosaur Utahraptor in this role. It came into the spotlight in 2009 thanks to the Ice Age 3: Dawn of the Dinosaurs film. Here an oversized Baryonyx called Rudy is the pseudo-rex Big Bad who is even bigger than the ''JPIII'' spinosaur or the real-life one, and an excellent example of the Savage Spinosaurs and Spinosaurus vs. T. rex tropes.
The baryonyx is unnamed however (some dino-fans wrongly thought he's a Suchomimus), and also quite inaccurate, with a head shaped like a literal crocodile's and hands lacking the distinctive thumbclaws. Rudy is an albino; unlike chameleon-like carnotaurs, albino dinosaurs were possible in Real Life but probably very rare, and the predatory ones shouldn't have been good hunters because of their non-mimetic color and eyesight problems. In 2018,the Jurassic Park franchise added the Baryonyx as one of the animals in its 5th movie.
Smaller Tyrants: Albertosaurus, Gorgosaurus & Daspletosaurus *
It's Albertosaurus, and not Tyrannosaurus rex, the most abundant tyrannosaurid in fossil record, and it's also the second big-sized theropod by wealth of fossil material, just after the unbeatable Allosaurus. And yet, Albertosaurus has not gained much attention in films and comics as Tyrannosaurus tyrannosaurids are so similar to each other that if one appears in cinema, people will always call it T. rex. To compensate, Albertosaurus is a very common sight in many paleo-books, just as common as several other stock theropods. Its full name, Albertosaurus sarcophagus, means "meat-eating Alberta's lizard".
Like Tyrannosaurus, Albertosaurus is portrayed as the superpredator of its time, North America 71-68 million years ago, 5 million years before T. rex. The menu of an Albertosaurus was probably not monotonous; several kinds of herbivores roamed North American plains at the time, from ceratopsians to hadrosaurs, from the armored ankylosaurs to small swift ornithopods and ornithomimids. Even though tyrannosaurids are classically shown battling some powerful prey, they more probably hunted young individuals more often, to avoid the risk of fatal injuries or consequent infections.
Compared with the legendary Tyrannosaurus rex, Albertosaurus was like a leopard compared with a lion; smaller (30 ft/9 m long against the 40 ft of T. rex), it was also more slender, with longer, thinner jaws, smaller teeth, and more agile legs apt to higher top speeds than Tyrannosaurus. It had also small but distinctive "hornlets" above its eyes; one could thus say it was a tyrannosaurid version of Allosaurus. Even the herbivores which shared their world were matched with tyrannosaurids; those which lived alongside T. rex were bigger, slower and more heavily armored than those living with Albertosaurus.
Albertosaurus was also the first dinosaur ever discovered in Canada, at the end of the 19th century, but was named only in 1905 (incidentally, the same year as Tyrannosaurus) after the Canadian province of Alberta, where most of the abundant Canadian dinos have been discovered. Albertosaurus has also contributed indirectly to the popular image of tyrannosaurs. The forelimbs of Albertosaurus have been known since its very first find, while those of T. rex were first discovered only in the 1990s; for almost a century the well-known two-fingered hands of "rex" have been modeled upon those of Albertosaurus, debunking at the time the old pop-cultural Hand Wave about portraying three-fingered tyrannosaurs. note
Discovered in 1914, Gorgosaurus libratus ("balanced monster lizard") is another North American tyrannosaurid which was long considered a distinct genus compared to Albertosaurus. Then, in the 1970s, Canadian paleontologist Dale Russell found the two animals so similar they had to been put under a single name: since the first created name always has priority, so was Albertosaurus. Only in recent years, scientists changed idea again separating "Gorgosaurus" from "Albertosaurus" — the whole process is always quite arbitrary in paleontology, never forget this. There has also been a curious sequence in pop-portraits: Gorgosaurus has long been the most depicted non-"rex" tyrannosaur in classic paleo-art and old books, also thanks to a famous painting made by Czech paleoartist Zdenek Burian in the 1910s which started the trope; then, its long-lasting synonimization with Albertosaurus harmed its relevance, and Albertosaurus was usually regarded as the new prototypical small North American tyrannosaur until 2013, when Gorgosaurus made its way into cinema by playing the main antagonist of the Walking with Dinosaurs.
In the 1970s, a third North American tyrannosaur was recognized as distinct from Tyrannosaurus and Gorgosaurus/Albertosaurus: Daspletosaurus torosus (the genus name meaning "frightful lizard"). The same size of the latest two and living in the same epoch, Daspletosaurus was actually more similar to T. rex than to Albertosaurus/Gorgosaurus in anatomy, and some thought it was the rex's direct ancestor - but this is not certain. Many scientists think the more agile Albertosaurus/Gorgosaurus specialized on relatively easier prey such as hadrosaurs, young ceratopsians, troodonts or ornithomimids, while the more powerfully-built Daspletosaurus hunted armored herbivores like adult ceratopsians and ankylosaurs. The daspletosaur appears as one of the four protagonist dinosaurs of the docu-series Dinosaur Planet: a youngster named "Little Das" analogue and opposite to the allosaur "Big Al" of Walking with Dinosaurs.
- Entry Time: 2000s (Albertosaurus); 2013 (Gorgosaurus); 2003 (Daspletosaurus)
- Trope Maker: Jurassic Park: Trespasser (Albertosaurus); the Walking With Dinosaurs film (Gorgosaurus); Dinosaur Planet (Daspletosaurus)
The Asian Tyrannosaur: Tarbosaurus *
Tarbosaurus bataar means "Mongolian alarming lizard". If you want to describe it, dont worry, its a simple thing: just say it was the Asian twin of Tyrannosaurus rex and youve given the idea. To be more accurate, Tarbosaurus was slightly smaller than Tyrannosaurus, with a larger head and a slightly lighter trunk, but shared with the "rex" the same familiar body-shape. Its forelimbs were identical to T. rex but a bit smaller, sometimes cited as the smallest arms in the dinosaur world - even though the horned theropod Carnotaurus had even more reduced arms, as did some flightless birds like the recently-extinct Moas (see below) and others.
Tarbosaurus was the "king" of the predators in its habitat, Late Cretaceous Asia, just like T. rex in North America. These two dinosaurs are so similar, that some scientists suggested in the past that Tarbosaurus is another species of the genus Tyrannosaurus (Tyrannosaurus bataar), but the newest studies seem to disagree. Maybe some smaller North American tyrannosaurs were closer to T. rex than Tarbosaurus. The tarbosaur may be closest to Zhuchengtyrannus, an Asian tyrannosaur named in 2011, while "Jenghizkhan" (from the Mongolian Gengis Khan), described in 1995, is today just an invalid synonym of Tarbosaurus.
Tarbosaurus was very similar to T. rex but wasn't identical, and there were differences that inexperienced writers and artists often miss. For example, Tarbosaurus had a narrower, less powerful skull, a unique locking mechanism, less-binocular vision, and smaller but sharper and more serrated teeth than its American cousin, suggesting it was not as adapted to feed on armored prey like ceratopsians and ankylosaurs, and instead favored preying upon large hadrosaurs.
Tarbosaurus has been first discovered in 1955 in Mongolia, more precisely in the Gobi Desert. Mongolia, a sparsely populated Asian country bordered by Russia and China, has always had a major role in the brief history of paleontology: despite being much smaller than China, Canada or the USA, it has given us the same number of fossils of each of them, almost all from Late Cretaceous. Among them, most of the classic Asian dinosaurs: from the famed Protoceratops/Velociraptor battle to the first Mesozoic dinosaur eggs ever discovered, from oviraptorids to the huge Deinocheirus, from the duckbilled Saurolophus to the ostrich-like Gallimimus to the "parrot dinosaur" Psittacosaurus, ankylosaurs like Pinacosaurus, titanosaur sauropods, small pachycephalosaurs, the birdlike Avimimus, Segnosaurus, Saurornithoides, Mononykus, and the scythe-claws of Therizinosaurus.
Interestingly, the succession of geological periods (Cretaceous-Jurassic-Triassic) of the Mesozoic era, have also a distribution in latitude which is amazingly specular in Asia and in North America. In both continents, the Cretaceous terrains are those in the northern part of the range (Alberta, Canada/Montana, USA, and Mongolia/Inner Mongolia/Northern China); the Triassic terrains are the most southern (Arizona/New Mexico, USA, and the province of Yunnan, southern China); while the Jurassic one were in the middle (Utah/Colorado/Wyoming, and the province of Szechuan, central China). Also note that most North American dinosaurs have been discovered in western USA and western Canada (not in the coastal region however, but only in the Mountains and Plains); while the Asian dinosaurs are concentrated in only two countries, Mongolia and China, both in the Far East.
Despite (or perhaps because of) its similarity to T. rex, Tarbosaurus has rarely appeared in fiction. Its first notable appearance was in the original novel Carnosaur by John Brosnan, and it was also in Chased By Dinosaurs. More recently, Tarbosaurus has become the star of a South Korean animated film titled Speckles: The Tarbosaurus.
Sail-backed Allosaur and One-horned Carnotaur: Acrocanthosaurus & Majungasaurus *
Spinosaurus was not the only theropod with a ridge on its back made by elongated neural spines: there were others as well. Acrocanthosaurus is the most well-known among these others. However, its sail was very different; only one foot tall, it extended from the neck to the tail-tip, while that of Spinosaurus was far higher but limited to the back. Actually, the sail of Acrocanthosaurus could have been buried in flesh in the living animal, making it looking even bigger when seen from the side, just like what could have been for Spinosaurus.
Acrocanthosaurus ("tall-spined lizard") was not a spinosaur relative at all, even though it and other sailbacks were classified as such in the past just because of their sails: actually was an allosauroid, traditionally classified as being between Giganotosaurus and Allosaurus phylogenetically (the most recent analyses support carcharodontosaurid affinities, making it closer to Giganotosaurus). Acrocanthosaurus lived in Early Cretaceous North America, rather between Allosaurus and Tyrannosaurus in the time scale. Apart from the sail it was similar to a robust Allosaurus in shape, and with its 12 m long body was as big as Tyrannosaurus rex, albeit of lighter build.
One could even say Acrocanthosaurus combined the best powers of the four most popular giant theropods. The size of "rex", the overall robustness of Giga, the powerful three-clawed forelimbs of Allo, and a crested back like Spino. And yet, have you sometimes seen this dinosaur outside dino-books (apart from the pseudo-docu Monsters Resurrected)? Things get even worse if you think Acrocanthosaurus has been known since the 1940s from rather complete remains, was the top-predator of Early Cretaceous North America, and shared the same habitat with another famous (but much smaller) killer dinosaur" Deinonychus. However, Bob Bakkers scientific novel Raptor Red does justice to Acrocanthosaurus, portraying it as the great predator of the world in which Utahraptor are the main characters.
Many Carnotaurus relatives showed some kind of ornamentation on their skull, though none had the "bovine" horn of a Carnotaurus. Majungasaurus crenatissimus is an excellent example of this. One of the few dinosaurs found in Madagascar (Majunga is the city near the site it was dug out), it was not bigger than Carnotaurus and shared a similar overall look, but with shorter legs and one single horn atop of its head.
This dinosaur has had a curious Science Marches On story: initially only its blunt horn was known, and because of its shape was thought to be the domehead of a tiny pachycephalosaur called Majungatholus. Then, this name was applied to the carnivore until few years ago; for example, in the wrestling-style pseudo-documentary Jurassic Fight Club this theropod appears named Majungatholus. Here, two adults are shown cannibalizing a young of their own species; this was based upon some marks of teeth on the bones of young Majungasaurus specimens, whose shape match the teeth of adult Majungasaurus. Another dinosaur which once was famous for being described as cannibalistic is Coelophysis, but see in another section for this one.
- Entry Time: 1995 (Acrocanthosaurus); 2008 (Majungasaurus)
- Trope Maker: Raptor Red (Acrocanthosaurus); Jurassic Fight Club (Majungasaurus)
Horned rex or Underdog?: Ceratosaurus *
Ceratosaurus nasicornis ("horned-nosed horned lizard": -nasicornis is Latin for horned-nose, while cerato is Greek for horn) lived in the same places as Allosaurus in the Late Jurassic, 153-148 mya. Usually 17-23 ft/5-7 m long, it was usually smaller than the other Stock Theropods above, but still a powerful animal.
Ceratosaurus looked more like an undersized allosaur than the others, having the same eye-bosses and long forelimbs of it. Its name underlines its more distinctive anatomical feature: a laterally flat crest on its nose, classically described as a "nasal horn". note It was also the only known theropod to have a true armor in the form of bony plates along the middle of its neck, back, and tail. While the "horn" is the hallmark in every Ceratosaurus portrayal (don't be surprised to see it shaped like a rhino's), the armor can be left out altogether, or alternatively, modified to make the animal similar to a dragon.
Despite its appearance, Ceratosaurus was actually more archaic than Allosaurus. Allosaurus belongs to the Tetanuran branch of theropods, while Ceratosaurus is the namesake of its own branch, Ceratosaurians. The latter can be told apart from tetanurans by the primitive shape of their pelvis, more flexible tails, and a remnant forth finger on each hand (tetanuran theropods never have more than three fingers). Most of the other theropods discussed in Stock Dinosaurs are tetanurans, except fellow ceratosaurians Carnotaurus & Majungasaurus and the two even more primitive most known coelophysoids, Dilophosaurus and Coelophysis.
Ceratosaurus was first found during the Bone Wars like Allosaurus, but is much rarer in the fossil record than the latter: many paleontologists suspect it was more solitary than allosaurs. In paleo-art and documentaries, Ceratosaurus can be shown either as a scavenger / an underdog predator, or as a pack-hunter of big game. While Allosaurus is seen as the "lion" of its time, Ceratosaurus might be considered the "hyena"; with its smaller size, longer teeth and stronger jaws, the comparison works. Since Real Life spotted hyenas are not lions' underdogs as seen in The Lion King, with both co-dominating the top-predator niche, its possible that ceratosaurs and allosaurs had a similar relationship; but also remember that comparing dinosaurs with modern mammals is always problematic in paleontology.
The horn on its nose and the armor make Ceratosaurus the most "dragon-looking" of the theropods known at the start of the 20th century (remember that all the carnivores in this folder were found later than it). It's not a big surprise that it appeared in so many classic dino-films, from simple cameos like Fantasia up to being the main dino-actor, like the Ray Harryhausen film Animal World, in which two ceratosaurs get into a fight and fall off a cliff.
Ceratosaurus holds the record of being the first dinosaur ever shown in non-animated cinema the 1914 film Brute Force pitted cavemen vs dinosaurs and started the Dinosaurs Are Dragons trope, making the ceratosaurus very important within the relatively brief history of popular depictions of dinosaurs. In later fiction Ceratosaurus received the same treatment as Allosaurus, acting as a T. rex substitute for the Big Bad part. With its distinctive horned/armored look, Ceratosaurus is less likely than Allosaurus to be confused with Tyrannosaurus; on the other hand, its size is often exaggerated to make it more of a "horned tyrannosaur", like in another Harryhausen's movie, One Million B.C., where it's seen fighting a Triceratops but is gored to death by it.
Ceratosaurus is quite rare in films these days: the only recent example is a short cameo in Jurassic Park III, in which it's not even named, but at least is correctly sized. Allosaurus entered the Jurassic Park franchise only in 2018, in the Jurassic World sequel "The Fallen Kingdom" with a brief cameo as well. Even modern documentaries rarely represent the ceratosaur the Walking with Dinosaurs series didn't show it at all for some reason. The recent Ceratosaurus decline is probably due to the occurrence of the other, newly-discovered big predatory theropods described above: Carnotaurus in particular, being similar yet even more badass looking for some thanks to its two bull-like horns.
- Entry Time: 1914
- Trope Maker: Brute Force (film)
The First named non-bird Dinosaur: Megalosaurus *
We've already mentioned Megalosaurus more than once. Why? Well, both because it was the first giant theropod known to science, and because shows neatly how Science Marches On is normal stuff in dino-science.
Its first remain, the extremity of a leg-bone found in 1676 in England near Oxford, was mistaken by Robert Plot for the remain of an ancient giant man (others named this remain Scrotum humanum because of its shape), but this fossil has since been lost. Later, a half lower jaw with a single large tooth left was found in 1824 in Southern England; its discoverer, reverend and geologist William Buckland, described it as belonging to a "big lizard" (the meaning of its name, which started the tradition of "saurus" in dinosaur names). Buckland didnt realize he had named the very first non-avian dinosaur.
The scientific and popular view of what a megalosaur was has gone through several drastic changes. The first attempt at reconstruction, the life-size sculpture in Crystal Palace Park constructed in the 1850s, made the Megalosaurus a dragon-like animal walking on all fours. Next to the Megalosaurus was an Iguanodon sculpture (also quadrupedal), and for several decades this was the stock image of the world of dinosaurs: one herbivorous dragon facing a carnivorous dragon in combat◊. From this time is Charles Dickens' novel Bleak House (1853) where Megalosaurus is mentioned, described as an "elephantine lizard". This is the very first time a dinosaur is cited in literature (the ichthyosaur and the plesiosaur of J. Verne's Journey to the Center of the Earth are NOT dinosaurs).
New genera of large carnivores were described during the Bone Wars, such as Allosaurus and Ceratosaurus, whose more complete remains showed clearly bipedal animals. Since then, Megalosaurus has also been reconstructed as bipedal. Even with their correct shapes, the "Megalosaurus vs Iguanodon" battle has remained a classic in non-fictional portrayals (a bit like "Tyrannosaurus vs Triceratops"), even though in Real Life the megalosaur was a middle Jurassic animal (166 mya), while the iguanodont lived 40 million years later in the Early Cretaceous.
The tendence to classify theropod fossils of every kind as Megalosaurus started soon after its first description. After the Bone Wars, Megalosaurus still remained a "Wastebasket taxon" to which all finds that were too incomplete or too ambiguous were assigned. Megalosauruses cropped up everywhere from North America to Africa to Australia, and from Early Jurassic to Late Cretaceous. Later, scientists progressively sorted out outsiders into more than 20 genera (Carcharodontosaurus, Dilophosaurus, Eustreptospondylus, Altispinax, Metriacanthosaurus, Majungasaurus, and Proceratosaurus among them). This cleanup has yet to be finished. See also Prehistoric Life - Large Theropods.
The only-valid Megalosaurus species is named Megalosaurus bucklandi from its discoverer Buckland. It's a fairly generic theropod some 30 ft/9 m in length, similar to an elongated allosaur but slightly smaller and more primitive, with little-visible brow-horns but robust jaws and teeth, and three powerful claws on each hand. Some old popular portraits represent it as very massive and powerful, hunting alone even giant sauropods like Cetiosaurus.
Even though its historical relevance makes it a common sight in classic and modern dino-books (expecially common are the photos of its original jaw), the "big lizard" didn't go a long way in popular works after the two important mentions in early literature (Bleak House and The Lost World). In the 20th century it heavily suffered the competition with Tyrannosaurus and Allosaurus and the resolution of the "wastebasket" issue made the case against it even worse according to some, while according to others this cleanup had little influence to the "megalo"'s decline which had already started before the reclassification of the other alleged species. Apart from some occasional documentary like Walter Cronkite 's "Dinosaur!", you have little chance of seeing any megalosaur either in cinema or in TV media just as an example, Walking with Dinosaurs chose to portray the contemporary close-relative Eustreptospondylus (once called Megalosaurus oxoniensis) in the Jurassic Europe episode, being scientifically better-known though smaller/more slender than M. bucklandi. But worthy of note is the TV show Dinosaurs which has one "megalosaur" in the form of Earl Sinclair, which is the main dinosaur-character of the series: he's an anthropomorphic dinosaur who doesn't look particularly like any kind of Real Life dino, but is portrayed as robust and massive, reminding very vaguely the Crystal Palace Megalosaurus in this.
- Entry Time: 1854
- Trope Maker: Crystal Palace Park
Slender, double-crested Forerunner: Dilophosaurus **
Dilophosaurus wetherilli lived 197 million years ago in Early Jurassic North America. It was one of the first theropods to have exceeded human size: 20 ft / 6 m long, like a big Nile Croc/American Gator, but with a slender body frame compared with the animals above, and weighing 500 kg (like a medium horse), while Ceratosaurus was about the same length but double the weight, being more robustly-bodied. Despite its size could make thinking the "dilopho" was closerly related with some of the large theropods of this folder, like indeed Ceratosaurus, it was actually closer to the dog-sized Coelophysis: that is, it was a overgrown coelophysoid. Among the big theropods here, the closest to Dilophosaurus were the Ceratosaurians.
Its most easily recognizable trait in Real Life is the two parallel bony crests on its skull perhaps occurring only in males, probably used for display; they were present, though less-developed, in other coelophysoids like the neighboring 20 ft / 3 m long Coelophysis kayentakatae. The dilophosaurian crests were thinner and more delicate than the robust horns and cranial prominences of Carnotaurus and Ceratosaurus, and are classically thought easily breakable crests in a fight; so, the dilophosaur was traditionally thought a no-badass dinosaur because of this. Its head was long and narrow, and the upper jaw also had a deep indentation on each side near the tip of the snout, apparently making the whole structure even weaker. However, popular dilophosaur portraits usually don't show this pair of "pits", which were also present (but much smaller) in Coelophysis and other relatives. Scientists have usually said the dilophosaur was a mere scavenger or a small prey hunter, even though some had initially described it as the "the first giant killer dinosaur". It was indeed one of the biggest terrestrian carnivores of its time; however, really powerful meat-eating dinosaurs only started to appear in the Middle Jurassic, like Megalosaurus above. note
Dilophosaurus was first described in 1954 in Arizona from scant remains lacking the head, and was initially thought to be another species of the "wastebasket taxon" Megalosaurus. The first head complete with double crest was found only several years later; in 1970, the animal received the name Dilophosaurus, "double-crested lizard". Several footprints found in Early Jurassic terrains of the USA might have been made by dilophosaurs, but the exact identity of dinosaurian tracks cannot be told with certainty. One of these tracks was made by a swimming animal which barely touched the bottom with the tips of its feet.
It's unlikely that many people outside the dino-fandom had ever heard of Dilophosaurus before the novel Jurassic Park was published in 1990. Here it was depicted as capable of spitting venom like some species of cobra, which it probably couldn't do in Real Life: venomous saliva is unknown among modern birds and crocodiles. Other much smaller theropods, like Sinornithosaurus and Scipionyx, were also believed venomous at one point, this time by scientists and not by pop-writers, because of some long acute teeth apparently looking like the snake's or Gila lizards' fangs; but there has never been real concrete proof of poisonous drooling in every theropod or non-theropod dinosaur.
Two years later, the JP movie made the dilophosaur even more popular and even more incorrect. Its size was greatly decreased note , but above all, Spielberg added a totally improbable Frilled Lizard-like cowl on its neck. It certainly did not have this frill; it would require a lot of specific musculature on the neck, and the imprint of this would be visible on the skeleton (it isn't). Still, most later popular depictions have represented Dilophosaurus with this thing.
Just like Velociraptor, Dilophosaurus became a household name after the film, commonly known as the Spitting Dinosaur. Even though it has not appeared in any of the sequels except for a quick cameo as a hologram in Jurassic World, the JP portrayal has remained in pop-consciousness so much that prevented the Real Life animal from become more widely-known for long. One of the first venom-less/frill-less portrayals in TV was in the 2001 Speculative Documentary When Dinosaurs Roamed America, in which is shown correctly in Early Jurassic, and appears as the main predator of the story (the other predator is its smaller relative C. kayentakatae, identified with the old name "Syntarsus"). Today, the ever-increasing public interest in dinosaurs, mainly started thanks to Jurassic Park, is making Spielbergs Mix-and-Match Critter more and more of a Lost Subtrope.
In 2020, a new discovery has partially thrown what we knew about Dilophosaurus out the window, namely the long-thought weak jaws and easily-breakable double-crest. The jawbones show they provided scaffolding for muscle attachment, meaning the jaws were actually powerful, the upper teeth behind the two "pits" were strong, and the crests were even possibly reinforced by a system of air sacs, perhaps used as an inflating or resonating or cooling system, like what has been classically hyped to explain the cranial shape of some hadrosaur ornithopods, like Edmontosaurus and Saurolophus.
Other large theropods
Sorry, these ones aren't here. If you're looking for Alectrosaurus, Yutyrannus, Dryptosaurus, Eustreptospondylus, Yangchuanosaurus, Megaraptor, Gasosaurus, Irritator, Concavenator, Aucasaurus, Torvosaurus, and others, see here.
Several bird-like and bird-looking (usually small) theropods make appearances in media, although less commonly than the three "raptors" of the Great Stock section. Here we mention those with teeth: the toothless ones are in the following folder. Most toothy birdlike theropods here were somehow related with dromaeosaurids, or were actually members of this group.
The "Missing Link": Archaeopteryx **
Archaeopteryx lithographica note lived around 150-148 mya in Late Jurassic Europe. The name Archaeopteryx means "ancient wing" or "ancient feather"; another obsolete synonym very common in old textbooks was Archaeornis, "ancient bird". Both terms are very meaningful about its historical relevance. lithographica means "from the lithographic (stone)" because the flat rocks it was found in were used in the past as tables for writing. And it is even sometimes known as the "Urvogel", which is German for "original bird" — it's rare that a dinosaur receive a common name that is not a mere translation of the scientific one, unlike Ice Age critters.
Archaeopteryx was discovered 1861 in the famed Solnhofen deposit in Germany, whose rocks have preserved fossils so well that even soft parts of animals are visible. Because of this, most specimens of Archaeopteryx found later in Germany (about 6-7) were found with impressions of feathers.
Charles Darwin had published On the Origin of Species two years earlier of the finding of the first "archie" fossil, and in the following debate this "half-reptile, half-bird" became a key piece of evidence, as the ultimate example of a "missing link" between two animal classes. Other examples were found later by scientists throughout the XX century: Ichthyostega (fish-amphibians), Seymouria (amphibians-reptiles), Cynogathus (reptiles-mammals), and several others, see Stock Dinosaurs (Non-Dinosaurs) and Prehistoric Life.
A century after the first description, Archaeopteryx was again used as crucial evidence, this time in John Ostrom's theory that modern birds had evolved within the theropod group. Before that, most scientists considered Archaeopteryx and its bird-descendants only distant relatives of dinosaurs, in part because in traditional zoology Feathers = Bird, and no other dinosaur was known with imprints of feathers. Even though one scientist (Darwin's pupil T.H. Huxley) already recognized the dinosaurian origins of birds as early as the late 19th century by studying the skeletal features, this was largely accepted only after the Dinosaur Renaissance note and definitively proven only in the 1990s after the find of the feathered "Liaoning theropods".
Archaeopteryx has had a somewhat unique role among stock prehistoric animals: just like the Dodo is the icon of Extinction, Archaeopteryx has been that of Evolution. Within the long-lasting debate between scientists and creationists, the latter went so far to claim Archaeopteryx fossils are just fake.
According to modern knowledge Archaeopteryx is just another feathered theropod possibly a bird, possibly a deinonychosaur, possibly more primitive than either. Highlighting its theropodian nature, one archaeopterygid skeleton with no signs of feathers was long classified in another theropod genus: Compsognathus, believed scaly like every other nonbird dino until few decades ago (see later). The size of a chicken, Archaeopteryx had a long bony tail (modern birds always have stubby tails), three claws on its forelimbs, running feet with an enlarged second toe claw (this was discovered only in the 2000s), jaws with small, pointed teeth, and feathers. The main difference is that its feathers aren't just skin-covering down; it has flight feathers of very modern-looking shape on its wings and tail. It probably could glide but it is unlikely that it could flap its wings for powered flight it didn't have the modern birds' keeled breastbone for powerful wing muscle attachment, but the usual "ventral ribs" seen in non-bird theropods. Maybe it simply used its claws to climb up trees and then glided to the next tree. Its diet probably consisted only of insects and small vertebrates, but no stomach contents are known; also, we don't know how it mated or if it cared its offspring.
Its classic status as "the first bird" is merely traditional at this point, and the start of the "bird lineage" within the theropod branch depends on the chosen criteria to define whats a bird and the "archaeo"'s exact position in the evolutive tree. Still, it remains one of the most ancient known dinosaurs found with imprints of feathers, one of the very rare ones from the Jurassic (most of the others, like Microraptor or Sinosauropteryx, were Cretaceous).
In media, Archaeopteryx is well-established as the "first bird". It will sing like a bird and perch like a bird, neither of which was possible for the real-life Archaeopteryx; expect it to fly like a modern bird too, though later studies showed that, though it could actively fly, it likely wasn't very good at it and only did so in times of emergency or when it was convenient—these studies revealed that its flight patterns would've been fairly similar to a modern pheasant or quail, known for be mostly ground-dwelling birds. Media archeopteryges will lack the sickle claws on their feet, and occasionally also their wing-fingers and teeth, making them looking like full modern birds (see the cartoon Dinosaucers for an example of toothless, fingerless archaeopteryx). But, contrastly, expect also to see them with naked heads in dino-books, making them resemble feathered lizards. Actually, their heads would have been almost totally feathered like deinonychosaurs and most modern birds, see Raptor Attack.
Strangely, despite its iconic status, Archaeopteryx has yet to appear in recent CGI docus: Walking with Dinosaurs misses completely it, despite the fact that its world, Late Jurassic european small islets, is shown in Cruel Sea. Even the franchise Jurassic Park never mentions it. To compensate, it shows up in Disney's Fantasia and in other fictional works, but usually as a simple ambient-animal with minor roles.
- Entry Time: 1861
- Trope Maker: Darwin's On the Origin of Species
The "Big Brain": the Troodon/ Stenonychosaurus/ "Dinosauroid" case *
This has been a complex case of Science Marches On, but also an astounding example about how imagination can be a very influential factor even for people studying dinosaurs seriously.
Living in North America some 75-65 million years ago alongside giant tyrannosaurs, Troodon formosus and Stenonychosaurus inequalis were small dinosaurs, but bigger than Archaeopteryx: they were around 7.9 ft/2.4 m in length and weighing some 110 lb/50 kg. Stenonychosaurus was still the largest member of the Troodontid family, a sibling family to Dromaeosauridae and among the closest relatives to birds. Troodontids looked a lot like dromaeosaurids, including being covered with feathers. Specifically, Stenonychosaurus was rather similar in shape to the Real Life Velociraptor; you can tell apart the two by observing the "steno" 's shorter head, smaller teeth, eyes pointing forwards note , shorter tail, longer legs, and smaller weaker sickle-claws on their second toe.
Since the 1980s Stenonychosaurus/Troodon has/have attracted scientists' attention. Stenonychosaurus shows several very specialized anatomical traits: it had larger eyes and ears than most dinosaurs, perhaps indicating nocturnal habits, and its brain was relatively large for a non-bird dinosaur as well. Its forwards-pointing eyes show binocular vision similar to modern birds of prey; many old portraits showed it with bulbous eyes with cat-like or even gecko-like pupils, almost resembling humanoid aliens: remember that last detail, we'll return to it at the end. More realistically, it had bird-like eyes with round pupils. It used also to be imagined with opposable thumbs making its hands like an eagle's foot to better grasp its prey, but this is controversial.
The stenonychosaur's/troodont's actual diet is still debated: with their surprisingly small & relatively blunt teeth, they were likely mostly-carnivorous omnivores, though they used to be portrayed as specialist small-prey hunters (nocturnal mammals, dinosaur nestlings, lizards, frogs). Some recently have even hypothized they were herbivorous, but this is now mostly discarded. At the other extreme, some depictions attribute to them traditionally-dromaeosaurian traits such as pack behavior or the ability to kill large prey, which weren't possible in Real Life. Stenonychosaurus 's toothed jaws and sickle-claws were too weak to tear the meat of large living animals.
The first find was a single tooth named Troodon formosus, "handsome wounding tooth", one of the very first North American dinosaurs found (1856), before Hadrosaurus but after Anchisaurus, see in other paragraphs. This tooth was initially believed from a lizard, then from a pachycephalosaurian. Stenonychosaurus inequalis ("unequal narrow-nailed lizard") was described later than Troodon, in the 1920s, but classified as a generic "coelurosaur". In 1987, Canadian paleontologist Phil Currie found the two animals to be one and the same, and the name Stenonychosaurus fell in disuse in favor of the name Troodon, being created first. If you read popular dino-books written before the 1990s you'll probably find the name "Stenonychosaurus" more often.
Also in the '80s, scientists found the stenonychosaurs braincase to be the biggest for its body size among all nonbird dinosaurs: this has given it the reputation of "the smartest dinosaur" in popular books, indipendently from if it was called either Stenonychosaurus or Troodon. Dromaeosaurids too have been classically depicted as very smart animals, but the troodontids were considered the Up to Eleven example among sickle-clawed dinosaurs in matter of intelligence. On the other hand, Pachycephalosaurus, despite its swollen head that make it looking like a genius-dinosaur, had a small brain for its size. The stenonychosaur's/troodont's real intelligence is today very debated: its brain actually was smaller than the one of many modern birds, and "big brain" doens't mean automatically smartness. But also note that, despite the commonplaces, modern birds aren't foolish creatures at all: think about the parrots' ability to understand humans' feelings, or the ability of crows and other passerine birds to use tools to find food. This could mean the troodont might have been really a very intelligent creature, but its actual level of intelligence is not demonstrable from the fossils.
Despite the tend of The New '10s to show this particular dinosaur in documentaries, the troodont/stenonychosaurs presence in fiction has been only occasional (hence the only star above), and not related to the actual animal but to that could be called its "altmode". In 1982, when the time the animal was still called only Stenonychosaurus (and obviously portrayed as featherless), Canadian paleontologist and Phil Currie's colleague and friend Dale Russell conjectured a possible way that its descendants could have evolved had it not gone extinct along with the rest of the dinosaurs. If its brain had kept increasing in size, today it would have been comparable to a human's or even bigger. Combined with further evolution of its bipedal movement, binocular vision, and semi-manipulative hands, the resulting "Dinosauroid" was proposed to be a blend of featherless dinosaurian and humanoid features. This hypothesis was very popular in the eighties and nineties, to the point the animals itself has been modeled with humanoid traits like the aforementioned bulbous eyes and prehensile hands. The Dinosauroid has made a few appearances in novels and TV series; its Real Life dino-ancestor usually gets mentioned. It's also worth noting that the Dinosauroid model resembles the Sleestaks of Land of the Lost (1974-1977), possibly a case of Ascended Fanon.
Always in The New '10s, Troodon's validity has been called into question, as the type specimen only consists of one tooth. While Troodon falls into taxonomic limbo, many fossils assigned to it have been moved into genera of their own, while Stenonychosaurus has been resurrected, much as Brontosaurus was. Before the 1990s the name commonly used in media for this prototypical troodontid was "Stenonychosaurus": since the 1990s it has been outfamed by the name "Troodon", even though the name Stenonychosaurus could return popular again in The New '20s (see also the even more complex case of "Edmontosaurus" for comparison).
- Entry Time: 1980s
- Trope Maker: the "Dinosauroid" hypothesis in the 80s and the works inspired from it
Other Sickle-Feet: Dromaeosaurus & Saurornithoides *
After the Power Trio made of Deinonychus antirrhopus, Velociraptor mongoliensis, and Utahraptor ostrommaysorum, the most depicted Dromaeosaurid in media has traditionally been the namesake Dromaeosaurus albertensis ("Alberta's running lizard"). The eponymy is not a mere case however: this was indeed the very first discovered dromaeosaurid: 1920s, in Alberta, and the generic meaning of "running lizard" is because its sickle claws were missing in its original skeleton, and scientists initially believed it was a small tyrannosaur or a more generic small theropod. The image of a hook-footed dinosaur came to light only after the description of Deinonychus in the sixties, and the family Dromaeosauridae itself was created around the same time to include Deinonychus, Dromaeosaurus, and Velociraptor together.
Dromaeosaurus was the same size of real-life Velociraptor but with a shorter head without the concave profile, and stronger jaws and teeth; compared with Deinonychus, Dromaeosaurus head was smaller but with a wider snout (good comparisons with Utahraptor cannot be made because of the incompleteness of the latter's original skull). In spite of being less-frequently portrayed than them, Dromaeosaurus appears regularly in dino-books and has also made some appearances in TV documentaries. If you see a dromaeosaurid interacting with Tyrannosaurus rex or Triceratops in Late Cretaceous North America, it would be Dromaeosaurus note — unless the writers didn't know or just didn't care: some docus have shown Deinonychus or Velociraptor or even Utahraptor in this role. Walking with Dinosaurs dealed with the problem in a bizarre way: here, the dromaeosaurids are officially Dromaeosaurus but have the shape of Deinonychus.
In truth, every dromaeosaurid in the original Walking With series was a Deinonychus, Utahraptors included. And to make the "Utahraptors" and the "Dromaeosauruses" distinguishable, they show up simply with a different coloration: brownish the former with black spots on its body; blackish the latter with a yellow-red tailtip like a coral snake. In this show, "Utahraptor"s are also portrayed in the way dromaeosaurids were once represented in paleo-art: naked-skinned, they chase an iguanodont in packs, jump on it using their sickle-claws as spurs, and eventually killing it with (a quite exaggerated) ease. Many dino-books have made this thing Up to Eleven with Dromaeosaurus, depicting scenes in which these turkey-sized predators chase and kill in packs adult Edmontosaurus and Triceratops 500 times heavier. Current paleontology suggests that Dromaeosaurus and the other raptors hunted smaller (but still large) prey and only ate the carcasses of the giant herbivores.
Saurornithoides mongoliensis, meaning literally Mongolian pseudo-bird lizard, is the most known among the several Troodontid relatives, but unlike Dromaeosaurus, was found in Asia. It was originally called more simply "Ornithoides" ("pseudo-bird"), and shared the same Late Cretaceous habitat with two iconic similar-sized theropods, Velociraptor mongoliensis and Oviraptor philoceratops. Saurornithoides, Velociraptor, and Oviraptor were discovered together by the American expedition in Mongolia led by the famous adventurer and naturalist Roy Chapman Andrews in the 1920s, at the same time Stenonychosaurus was found in North-America. Like Dromaeosaurus, Velociraptor, and Stenonychosaurus, Saurornithoides was long considered either a peculiar "dwarf megalosaur" or a generic coelurosaur... until the 1970s, when it and Stenonychosaurus were put in their own family: the "Saurornithoidids", renamed Troodontids since the 1980s. Together, troodontids and dromaeosaurids made in turn the larger group called deinonychosaurians (lit. the "Deinonychus-like lizards"). Deinonychosaurs and dromaeosaurids are traditionally not the same thing: the former also include troodontids. Some analyses in 2013 have recovered troodontids as being avialans, in which case they would actually be closer to modern birds than dromaeosaurids, while other workers think they are neither deinonychosaurs nor avialans.
Traditionally, both Troodon/Stenonychosaurus and Saurornithoides have been depicted as cunning nocturnal hunters who used their large, forward-facing eyes with slit pupils, as well as their great intelligence to catch small mammals, grasping them with their three-fingered hands weaponed with curved claws and opposable thumbs. More realistically, their eyes were bird-like with round pupils, their hands were not so prehensile, and their great smartness is debatable (see Raptor Attack). Furthermore, according to recent research, at least Troodon and Stenonychosaurus were more likely omnivorous a bit like ornithomimosaurs, because their teeth were tiny and not-so-sharp, resembling those of plant-eating dinos. Saurornithoides, having a slightly larger head and teeth than both, was more Velociraptor-like in external look (but not in its skeleton), and maybe it really corresponded to the former portrait of a specialized hunter. Some in the past have proposed that Troodon, Stenonychosaurus and Saurornithoides are actually all synonyms, but today the saurornithoid is widely regarded as a distinct animal from its north-american cousins.
- Entry Time: 1999 (Dromaeosaurus); 2009 (Saurornithoides)
- Trope Maker: Walking with Dinosaurs (Dromaeosaurus); Clash of the Dinosaurs (Saurornithoides)
Tiny Four-Winged Dinosaur: Microraptor *
Discovered in year 2000, Microraptor is one of the "Liaoning coelurosaurs", named small thief; as the "-raptor" suffix suggests, it was a dromaeosaurid. It was a find that surprised not only casual paleo-fans but also the entire paleontology community. And not because it was a feathered dino fossil (such animals were already known from the same site), nor just because it was the smallest non-avian dinosaur known at that point: merely 1.5ft long (but this record is contended now by other non-avian maniraptors and some primitive ornithischians). It was its unique body-plan that astonished us all: a four-winged dinosaur!
More precisely, its hindlimbs had a feather covering incredibly similar to that of its forelimbs, giving it its typical appearance. These wings had the same structure as the wings of true birds, with asymmetrical, vane-like feathers on the forelimbs, likewise on the hindlimbs, and placed in a "fan" at the tip of its long tail: in short, very similar to the kind of plumage of the well-known Archaeopteryx, itself recently found to have had remnants of such large feathers on its legs.
Of course, paleontologists and dino-fans have begun Wild Mass Guessing about its way of life. Since its discovery, Microraptor has been suggested to have been a tree-climber, with forelimbs as developed as the hindlimbs, both fitted with robust claws apt for climbing upright tree trunks; however, a study published in 2011 suggests it might have been terrestrial instead. The way it traversed the air is also controversial; with true flight like modern birds, or just simple gliding like modern flying squirrels, flying fish and flying lizards? Currently many scientists think Microraptor was actually a flier (although not as good as modern birds): it seemed to be even better adapted for flight than Archaeopteryx itself. If this is true, it would mean that flight evolved before the appearance of the so-called first bird, because Microraptor was probably less close to modern birds than Archaeopteryx was. And since flight was achieved in basal dromaeosaurids, this would mean that... yes, Velociraptor, Utahraptor, Deinonychus and all other dromaeosaurids may have descended from flying ancestors! One scientist did go Up to Eleven declaring that all maniraptorans descended from flying ancestors: this would mean, Troodon, Saurornithoides, Oviraptor, Citipati, and even the huge Therizinosaurus and Gigantoraptor were ancestrally creatures of the air, which, like ostriches or rheas, returned to a more ground-level way of life and increased their size. But all this is highly improbable.
Whatever the case was in Real Life, Microraptor immediately became the center of much interest soon after the year 2000, rapidly becoming popular in illustrated books — also because it was the considered the smallest dinosaur at the time; it became even more widely-known after being included as one of the main animal characters in the 2006 BBC series Prehistoric Park, where it was portrayed with the classic, splayed-limbs gliding style, now known to be anatomically impossible. Soon afterwards, it started to gain attention in the broader pop culture world, and it has to at this point be qualified as a true Stock Dinosaur, even if only in the Rarely-Seen section, with one single star on the top. See "Guido" of the 12th The Land Before Time sequel for an example. Today, other dromeosaurids similar to Microraptor are known to science, all small-sized like it. Microraptor was even victim of one of the most astounding paleontological hoaxes of the New Millennium: see "The Archaeoraptor Fake".
Mix and Match Critters: Therizinosaurus & Segnosaurus *
Most dinosaurs would appear as a bunch of Mix-and-Match Critters if alive today, with traits resembling those of mammals, bird, and crocodiles. But the Mix-and-Match Critter trope can also be applied in a more subtle way. Some relatively unknown dinos actually resembled strange mixes of more familiar dinosaurs, rather than modern animals. Segnosaurus galbinensis, Therizinosaurus cheloniformis and their relatives are perhaps the best example of this in the whole dinosaur world: another often-cited example is the sail-backed ornithopod Ouranosaurus, others are the giant non-predatory theropod Deinocheirus after the findings of The New '10s, and another fellow, Gigantoraptor, found in 2009.
Let's start with Segnosaurus. When the incomplete remains of it were discovered in the 1970s, hailing from Late Cretaceous Mongolia, this 24 ft/7 m long dinosaur made the scientists' eyes roll in their sockets: how could a dinosaur have the body-shape of a Plateosaurus, the forelimbs of a theropod, and an Iguanodon-like skull with a round bill at the front and grinding teeth behind? And, even though its pelvis was clearly saurischian in its overall structure, why did it have the pubis uniquely pointing backwards?
Taxonomists were totally confused, and finally placed Segnosaurus in its own group: the Segnosauria, along with three other less-known even more incomplete relatives (Erlikosaurus, Nanshiungosaurus, and the meaningfully-named Enigmosaurus), also Late Cretaceous and found in the same years of Segnosaurus in Mongolia or in China. The segnosaurians (lit. "slow lizards") were believed a separate evolutive branch which arose early in dino-evolution, and were classified in between theropods and sauropodomorphs, sauropodomorphs and ornithischians or sometimes even saurischians and ornithischians. A very similar scientific destiny occurred to the much smaller/ancient Herrerasaurians and Eoraptor, also described in the second half of the XX century in South America.
Science Marches On, however, and at the beginning of the 1990s, a much smaller relative of these segnosaurs, the 12 ft/3.5 m long Alxasaurus from Early Cretaceous China, clearly showed a coelurosaurian anatomy. This meant that segnosaurs were not only true theropods, but also members of the Maniraptoriformes, less-close to birds than oviraptorids and deinonychosaurs, but more than the ornithomimosaurs. Not only this: thanks to a more accurate comparison, it was discovered that the previously-enigmatic Therizinosaurus was another member of the same group - this had already been postulated before the nineties, but was still not demonstrable at the time. Today, Therizinosaurus, being cooler-looking, is more frequent in books than Segnosaurus and other members of the group, and the whole group is now officially named Therizinosauria in taxonomy, being Therizinosaurus the first genus to have been described by science. Therizinosaurus too has had its own Science Marches On story, totally independent from that of Segnosaurus, and more similar to that of Deinocheirus. We'll arrive ti that in a blink.
The diet of Segnosaurus used to be just as problematic as its classification. One early theory made it a fish-eater like Baryonyx and Spinosaurus, but slippery fish could have easily escaped from its round beak, and the theory was rapidly discarded. However, some paintings made in the eighties have shown Segnosaurus as a semi-acquatic fisher even with webbed feet: the last thing was based on alleged footprints. Indeed, the segnosaur had stockier hindlegs and shorter feet than most other theropods ("slow lizard", remember?), and with the usually-lifted forth reversed toe of typical theropods touching the ground, to bear its higher body-weight compared with most theropods of similar length: but this doesn't mean it was like a wading bird such as a wild goose or a heron.
Another early unlikely hypothesis made segnosaurians ant-eaters and/or termite-eaters because of their large handclaws apparently apt to dig into ant-nests and termite-mounds; but again, these dinosaurs hadn't the typical tubular muzzle of a mammalian anteater, and such large creatures perhaps couldn't have lived on insects alone. note Today, it's generally agreed that Segnosaurus and the other large therizinosaurians were specialized plant-eating theropods, strikingly convergent with ornithopods or early sauropodomorphs. This is the best theory also because explains their backward-pointing pubis: its function was probably to give space to the massive gut of a herbivore without losing the bipedality of a theropod. Furthermore, other theropods with backward-pointing pubes are also known now, most of which are coelurosaurs, including dromaeosaurids and birds, though these appear to have acquired their backward-pointing pubes through a change regarding which muscles they used for running. Even though other birdlike theropods (ornithomimids, oviraptorids) could have eaten fruits or other kinds of vegetation, only the most evolved therizinosaurians appeared specialized to a strict herbivorous diet based upon tree-leaves. If it wasn't for their unmistakeably theropodian forelimbs you could easily confound them with ornithopods like Iguanodon if they'd be alive today.
And now, Therizinosaurus: it could be considered a sort of twin of Deinocheirus for several reasons. It was colossal yet awfully bird-like, just like Deinocheirus; specialized to a non-big-prey-based diet, just like Deinocheirus; was discovered in Late Cretaceous rocks from Mongolia, just like Deinocheirus; is known mainly from forelimbs and few other bits, just like Deinocheirus before 2014; entered the dinosaur list around the same time as Deinocheirus; and, last but not least, it was another candidate for the title of biggest theropod, just like Deinocheirus! But, unlike Deinocheirus, Therizinosaurus was not a giant ornithomimosaur, but the biggest member of the Segnosaurians, today called Therizinosaurians.
Discovered in the 1950s but not recognized as a dinosaur until the 1970s, its forelimbs were slightly shorter but more powerful than those of the giant ornithomimosaur Deinocheirus. But Therizinosaurus had an additional curiosity: three scythe-like claws on each hand (hence its name, "scythe lizard"), some as long as a human arm. In short, it is believed to have had the biggest/longest nails known so far within the entire Animal Kingdom - even though some gigantic sauropods might have had even more massive thumbnails on their forefeet.
One of these oversized claws was in fact the first known find of the "therizino", and for several years, scientists thought it belonged to a giant marine turtle. Indeed, its fully scientific name, Therizinosaurus cheloniformis, means "turtle-shaped scythe lizard".
With such powerful weapons, Therizinosaurus has in the past received the same treatment as Deinocheirus. Some old drawings went as far as to show our "scythe-dino" as a giant carnosaur or deinonychosaur with sickle-claws on each foot: if Therizinosaurus was really shaped that way, it would really have been the most badass dinosaur one can imagine... More accurate analyses made at the beginning of the 1990s definitively debunked these fantasies: we now know with a good level of certainty that Therizinosaurus was a bulky-bodied, round-bellied, and quite slow-moving animal that used its claws mainly to pull down branches. Furthermore, its jaws were arguably weak with a rounded horny tip and small grinding teeth similar to those seen in its smaller but scientifically better-known relative Segnosaurus.
This doesn't lessen its general coolness: even with this new shape, Therizinosaurus remains an odd-looking, powerful beast, and thanks its massive body, it might even be the heaviest theropod ever discovered, weighing even more than the longer but more slender Spinosaurus: but this is not demonstrable for now obviously, due to its fragmentary fossils. Therizinosaurians, because of their shape and habits, have often been compared by scientists with giant mammals, like the ground sloths such as Megatherium, or the less-familiar Chalicotherians, see Stock Dinosaurs (Non-Dinosaurs). Some have even compared them with giant pandas, bears, or gorillas.
As we've long done with Deinocheirus, we dino-fans are patiently waiting for exciting new remains of our "Wolverine Claws-osaurus" to be excavated. Meanwhile, Chased By Dinosaurs from 2002 temporarily recreated our imagination in CGI: in the episode titled "The Giant Claw" Nigel Marven talks about Therizinosaurus, lampshading its whole Science Marches On story from a mighty carnivore to a Gentle Giant. Nigel is in Late Cretaceous Mongolia searching for the possessor of the eponymous "giant claw", which the zoologist believes to have pertained to a fearsome predator. After several adventures with other dinosaurs of the habitat (Saurolophus, Protoceratops, Velociraptor, Mononykus), Nigel witnesses a fight between Therizinosaurus and Tarbosaurus: even though the former unexpectedly reveals itself to be an herbivore, it easily defeats the tyrannosaur by slapping it in the face with its enormous scythe-claws, obliging the predator to flee. Finally, the therizinosaur licks Nigels face. Really!
- Entry Time: The 2000s (Therizinosaurus); undetermined for Segnosaurus
- Trope Maker: Chased by Dinosaurs (Therizinosaurus); its status of "the mix and match critter" dinosaur (Segnosaurus)
Other toothed birdlike theropods
Sorry, these ones aren't here. If you're looking for Caudipteryx, Sinosauropteryx, Beipiaosaurus, Mononykus, Achillobator, Saurornitholestes, Pelecanimimus, Nothronychus, Alvarezsaurus, Shuvuuia, Bradycneme, and others, see here.
The most known birdlike theropods lacking true teeth belonged to the ornithomimosaurs and the oviraptorosaurs, which didn't form a natural group together. Ornithomimus, Struthiomimus, Gallimimus, and Deinocheirus have been the most known members of the first subgroup; Oviraptor/Citipati and Gigantoraptor are today the most familiar of the second one. Among the latter, Avimimus owes the record of "the first known feathered nonbird dinosaur" (if you don't count the classic "missing link" Archaeopteryx).
Lighter and Faster: Ornithomimus & Struthiomimus **
Before Jurassic Park made the "raptors" popular in The '90s, ornithomimids used to be the animals that most often came to mind to people when thinking about small & agile dinosaurs, as the antithesis to the classical Mighty Glacier image.
Ornithomimus velox ("fast bird-imitator"), the prototype of the family, lived in North America between 75-66 million years ago, in the Late Cretaceous. It was 12 feet/3.5 meters long and weighed around 220-330 lbs/100-150 kg. Its shape was similar to a long-tailed ostrich. It had a long neck with a birdlike skull and a toothless beak. The brain and eyes were large (though not the same degree of troodonts), possibly an adaptation to support quick movement. Its body was short and compact, like that of a bird. Its tail was very long, balancing the animal when running. The legs were similar to modern running birds, with short muscular femurs, elongated tibias/shins, and three toes each (not four: it lost its reversed toe during its evolution). With this anatomy it may have been among the fastest non-avian dinosaurs, easily capable escaping the bigger and clumsier Tyrannosaurus rex.
Ultimately confirmed to be feathered, which was already suspected for some time. It certainly had down-covering; the adult specimens were argued to also have shafted feathers (similar to covert feathers of birds) on their forelimbs that most likely formed a wing-like structures called pennibrachia (though obviously not used for aerial locomotion).note
Ornithomimus is the prototype of the Ornithomimids, often nicknamed "Ostrich-dinosaurs" or "Ostrich-mimic dinosaurs". This family also includes its neighbor Struthiomimus altus ("tall ostrich-mimic") and other animals like Gallimimus bullatus. Struthiomimus was identical in shape and size to Ornithomimus: it had only longer forelimbs and bigger hands and handclaws. Struthiomimus was just as fast and quick as its Non Identical Twin Ornithomimus, and lived in North America in the same period: the two were actually considered the same animal at the time ornithomimids first entered pop-media, in 1940, and were definitively recognized as distinct only in the 1970s.
As their names suggest, Struthiomimus and Ornithomimus have unusually been recognized as birdlike dinosaurs since their very first discovery. Ornithomimus was the first described (USA, 1890, during the Bone Wars), while Struthiomimus was named later (Alberta, 1917). The first U.S. remains were fragmentary, though, and complete ornithomimids came to light only in the early 20th century. They were described as fast-moving and graceful even before the Dinosaur Renaissance, and usually portrayed with erect tail and horizontal body, unlike the giant bipedal dinos with their upright bodies and dragging tails.
Unusually for dinosaurs, media have never shown ornithomimes as scary killers dangerous to humans. This can be due to their lack of teeth that make them look harmless. Their actual diet is still uncertain, as no stomach remains are known for now. Their large numbers, among other things, seems to indicate that they were mainly herbivorous with insects, eggs, and small animals as a supplement. In popular media they have often been depicted as plant-eaters and/or insect-eaters, very rarely as meat-eaters. But the most common pop-portrayal has shown them as egg-stealers outwitting larger dinosaurs.
One good example is in The Land Before Time series. Even though they might have eaten some eggs, there is no evidence this was a major part of their diet. Furthermore, not being maniraptorans ("robbing hands"), they probably couldn't grasp things so easily as the latter did. Today in popular media the "robbing" role can be also attributed to other small theropods, like oviraptors. Finally, in the early 2000s it was suggested ornithomimids were filter-feeders like flamingos, as seen in the pseudo-documentary Prehistoric Park, but now this hypothesis is totally disproved by Science Marches On. In the original movie of the Land Before Time franchise an unnamed ornithomimid tempts unsuccessfully to steal Littlefoot's egg, while in the third episode of the series two villainous egg-stealing ostrich-dinosaurs are named Ozzy and Strut: a case of A Lizard Named "Liz", as Ozzy is arguably derived from "Ornithomimus", and Strut is clearly the initial of "Struthiomimus".
Another stock ornithomimid, Dromiceiomimus, has a rather tongue-twister name, but it simply means "emu-mimic". Dromiceius novaehollandiae is the old scientific name of the emu: now is Dromaius novaehollandiae, both meaning "Runner of the New Holland" (the old name of Australia). It lived in Late Cretaceous North America together with Ornithomimus and Struthiomimus. It was almost identical to the former in size/shape, but with longer legs and wider eyes: dino-books have often mentioned the dromiceiomimus as "the fastest dinosaur", able to run 70 km per hour like a running horse or ostrich, or "the biggest-eyed dino" (in respect to the body) because of its huge orbits. Found in the Seventies, well after its two neighbors, in the 2000s and 2010s it has widely but not universally reclassified from Dromiceiomimus to Ornithomimus edmontonicus. It is also one of the three characters of the webcomic Dinosaur Comics together with T. rex and Utahraptor.
Oviraptor lived in Late Cretaceous Asia 75 million years ago. This very bird-like dinosaur is another excellent demonstration about how Science Marches On is a crucial factor in popular dino potrayals.
First discovered in Mongolia in 1924 together with Protoceratops and Velociraptor, this toothless theropod was originally thought to be an ornithomimid. Since the 1970s it is classified into its own family, even more closely-related to birds. Oviraptor was distinct from ornithomimids by having a rounder, stockier beak, a shorter tail, and the small forth reversed toe on each foot present in most theropods (birds included), which was lost in many ornithomimosaurs. Unlike the latter, the oviraptor was a "maniraptoran" theropod: its forelimbs were bird-like, and it's considered to have had a very bird-like covering of feathers, with feathered wings and a feathered tail fan.
It was given the name Oviraptor philoceratops, meaning "ceratops-loving egg-thief", because the first specimen, a crushed skull, was found next to a clutch of eggs which were thought to belong to the small ceratopsian Protoceratops. In the 1990s the eggs were found to contain oviraptor chicks: the specimen was brooding its eggs. This was further confirmed few years later, when an oviraptorid skeleton was found just above a nest full of the same kind of eggs.
Before the middle 1990s scientists used to describe Oviraptors as a specialist nest-robbers, and documentary works have typically shown them frequenting the nesting ground of herbivorous dinosaurs (especially those of Protoceratops), grasping the eggs with their prehensile hands, and fleeing away from the angry mothers when they're discovered. The "robbing" behavior has often been attributed both in science and in popular culture to ornithomimids as well, but the oviraptors were considered specifically adapted just to eat eggs and no other kind of food unlike the more omnivorous ornithomimes, with their robust bill that was thought a specialization for breaking eggshells. Today, the actual diet of oviraptorids is a matter of speculation they might have been fruit-eaters, predators, or both; they might even have fed on eggs if given the chance, like possibly every small toothed or toothless theropod.
Since the first discovery the oviraptors have also notably changed their look: paleo-artistic works from before the 1990s usually depicted them featherless, and with a protruding palate with a pair of "teeth" at the tip, believed apt to break eggshells. In works made in the Eighties and the Nineties you can see the animal with two different head-shapes: the one with a small bony bump on its nose (the more classical original one, but inaccurate), and the one with a square bony flat crest, first emerged in the 1970s. This is the most common image today in paleo-works, see also Prehistoric Life to go deeper within the argument.
However, since the 2000s the most complete Oviraptor skeletons have been reclassified in a brand new genus, the non-Latin-sounding Citipati: the familiar square-crested image probably belongs to this new genus. Note that this is not the classic "Brontosaurus"/Apatosaurus case: the genus Oviraptor is still valid, with the only species O. philoceratops'; it's just that many specimens that used to be considered to belong to the genus are now considered Citipati osmolskae, and that the actual Oviraptor'' is very unlike its depictions, lacking any known crest and being far smaller that its emu-sized relative.
Unlike ornithomimids, oviraptorids have attracted the attention of dino-writers only since the 2000s: after the appearance of the feathered, non-egg-stealing scientific depiction. And yet, expect to see them portrayed in the older inaccurate way nonetheless, and you can easily see oviraptorids and ornithomimids mixed up with each other. E.g. in the 2000 Disney movie Dinosaur, a featherless "Oviraptor" steals Aladar's egg, but loses it before it has a chance to eat the contents. More recently, an "Oviraptor" named Ruby thanks to her color, appeared in The Land Before Time TV series: feathered and not egg-stealing. Both portrayals show the oviraptors with a Citipati-like tall crest on their head. While Dinotopia lampshades the animal's Science Marches On story showing it in two variations: the featherless "Oviraptor" and the feathered "Ovinutrix" ("egg-nurse").
Big and Small Runners: Gallimimus & Avimimus *
Discovered in the 1970s — much later than the two classical ornithomimids Ornithomimus and Struthiomimus — Gallimimus means "rooster-mimic", and was one of the largest ornithomimids: 20 ft/6 m long (like a Dilophosaurus or Ceratosaurus), with some reports of sizes up to 8 meters long, as long as some giant predatory theropods like Albertosaurus or Megalosaurus but still less-heavy than them due to its lighter body-frame.
It lived in Mongolia in the late Cretaceous, 70 mya, together with Oviraptor and Velociraptor, and its full scientific name is Gallimimus bullatus. Apart from its longer, wider, and blunter snout and slightly shorter legs, its appearance was that of an enlarged Ornithomimus or Struthiomimus, with small short forelimbs more similar to the former than to the latter. It belonged to the same family of its smaller north-american cousins, sharing with them the same skeletal anatomy: lack of teeth, long ostrich-like neck, and absence of the forth toe in the foot. Despite its size and weight (500 or more kgs) it was probably as fast and agile as them, and also its behavior in life was arguably similar. Obviously, it's hard to determine which ornithomimid was the fastest runner due to lack of fossil evidence. An interesting thing to note is that the ornithomimans had lateral eyes like most modern herbivores, not forward-pointing like typical carnivores —contrasting, for example, with Tyrannosaurus and Stenonychosaurus.
With its large fossil record Gallimimus has become a common sight in dino-books since the '80s, just as commom as Struthiomimus and Ornithomimus, and entered the pop-consciousness in 1993 after Jurassic Park the film, not the novel, which has the ornithopod Hadrosaurus in the stampede scene. Here a flock of Gallimimus is seen fleeing from the protagonistic Tyrannosaurus who manages to capture one. In the movie, however, this dinosaur has an overall secondary role in respect to the other six dinosaurs portrayed (except for Parasaurolophus, that makes only an even shorter apparition well before the appearence of Gallimimus). Both the ornithischian Parasaurolophus and the saurischian Gallimimus reappear in the 1st sequel in 1997 during the "dinosaur hunt" scene, together with Pachycephalosaurus and a giant unnamed sauropod; this time, however, the ostrich-dinosaur is not named. Other Gallimimuses named "rainbow faces" show up in one of The Land Before Time sequels as helpers of the protagonists in the 2000s.
Like Velociraptor and Dilophosaurus, Gallimimus became one of the Stock Dinosaurs immediately after the 1st JP movie, but has replaced Ornithomimus and Struthiomimus in pop-culture only partially. Fictional works from after 1993 can still add Ornitho- or Struthio- (or even "Dromiceio-") to their -mimuses, instead of Galli-.
But when did the Great Feather Adventure begin? The answer: in 1981, in the Mongolian Gobi Desert, the same place where Oviraptor and Velociraptor were first discovered. That year, a new kind of Late Cretaceous coelurosaur was described from a partial skeleton, which astonished the scientist who found it. He chose to name his find Avimimus - bird mimic, the same as Ornithomimus, only with a Latin prefix instead of Greek. Despite this, Avimimus was not an ornithomimid, but an only 5 ft / 1.5 m long, late-surviving basal oviraptorosaur only a bit bigger than a Compsognathus. Nothing special per se except for one thing: it was the very first dinosaur whose skeleton showed some evidence of feathers. Not prints on the rock, however, only a crest on its arm-bones that resembled that of modern birds.
For about 12 years since then, Avimimus has been the only non-avian dinosaur regularly portrayed with feathers often in an incorrect way: certain depictions first popularized by John Sibbick in the 1985 Dinosaur Encyclopedia showed it as a short-winged Archaeopteryx with the same head-shape, jaws filled with teeth, and splayed forelimbs, as if was about to take off. It actually had a short head and short arms typical of oviraptorosaurs, so it couldnt fly. However, Avimimus lacked a crest on its head, and also had serrations in its beak which could have worked as teeth, making it relatively similar to the archaeopteryx at a first glance. The full scientific name of this small but historically important dinosaur is Avimimus portentosus, "marvelous bird-imitator", underlining the relevance of its find and the subsequent implications about the Feather Theory, which has already been postulated since the seventies but without any concrete clue before that.
- Entry Time: 1993 (Gallimimus); undetermined for Avimimus
- Trope Maker: Jurassic Park film (Gallimimus); the status of "the first dinosaur with proof of feathers" for Avimimus
The Big Mystery Resolved: Deinocheirus *
Most bird-like dinosaurs were small and unimpressive in Real Life compared to most other dinosaurs. This definitively couldnt be said for Deinocheirus, living in Late Cretaceous Mongolia. Like Therizinosaurus, it is among the largest known theropods, and both were similar in size to Tyrannosaurus rex.
Deinocheirus mirificus means, astounding terrible hands, and should not be confused with Deinonychus antirrhopus, counterbalanced terrible claw. It was discovered in the 1970s in the Gobi Desert during an unusually rainy day for such an arid location, by the same Polish expedition that found the Protoceratops/Velociraptor fossilized battle and many other dinosaurs.
Only its complete forelimbs were found by the scientists, along with three-fingered hands, shoulder-blades, and some other fragments from the rest of the skeleton. The leading scientist of the expedition, Halska Osmolska, noted that these forelimbs were similar in shape to those of an ornithomimid only, they were twice the height of a fully grown human. To give you an idea of the scale, several drawings have then shown these immense arms encircling an adult human, with the three-fingered hands (each as wide as a big TV-set) shown like theyre going to grasp and then lift him/her. The documentary Planet of Dinosaurs is a good TV example of this. The drawings usually didnt show the whole body, because its shape was totally unknown.
After the discovery, a veritable Wild Mass Guessing started to understand what sort of thing Deinocheirus looked in life. Just as an example, some thought it had forelimbs longer than the hindlimbs: but this wasn't so, since this would have forced the animal to walk on four legs — an impossibility, since its hands were inapt for walking. We now know Deinocheirus had the same bipedal body shape of the classic theropods. Speculations about its size abunded as well. If its forelimbs had the same proportions of a Gallimimus, then Deinocheirus could have been bigger than a T.rex, and maybe as long as a Spinosaurus — and even taller, thanks to the longer neck. It was even said that it could reach the forth story of a building if alive today, and could have weighed as much as two elephants, that is to say, two T. rexes. But most experts didnt agree with these extreme ideas, and put Deinocheirus in the same size-range as Tyrannosaurus or Allosaurus. Moreover, being an ornithomimosaur, it was imagined rather slender-framed, and thus unlikely that was as heavy as two elephants: perhaps even lighter than T.rex.
And then, there has been all the speculation about its way-of-life. Early reports described it as a gigantic predator, but such an image was usually believed highly unlikely. Scientists didn't know if Deinocheirus was a basal toothed ornithomimosaur, or a derived toothless one: most agreed it should be put in its own family, the Deinocheirids, outside Ornithomimids proper, or even in its own suborder, Deinocheirosauria (distinct from Ornithomimosauria). If the toothy version was true, it could have been an active hunter, and someone could have even imagined titanic battles againts the contemporaneous T. rex relative Tarbosaurus or even Therizinosaurus, also often imagined a giant active predator at the time. But even with sharp-toothed jaws, Deinocheirus shouldnt be seen as such a powerful killer. Its jaws and teeth would be much smaller and weaker than tyrannosaurs', carnosaurs', or even spinosaurids'. Furthermore, its one-foot long handclaws are too blunt to be able to rip the tough skin of a hadrosaur or a sauropod. The main consensus was Deinocheirus was a sort of giant omnivore, which could have eaten from tree-tops using its forelimbs to pull down branches like a mammalian giant ground sloth or a chalicothere (convergent evolution), and at the same time could have scavenged carrion of large herbivores, destroyed ant-mounds and termite-mounds like an anteater or a pangolin, hunted small dinosaurs that could be swallowed whole, and maybe chased Tarbosaurus away from their kills using its terrible hands as a scaring device. Therizinosaurus got a similar description until The '90s.
To resolve the mystery, dino-fans patiently waited for a complete Deinocheirus skeleton for many, many years. Material described in 2012 was a step in the right direction: this shows that the original incomplete carcass was scavenged by a Tarbosaurus. But in the 2013, after 40 years of waiting or so, the so-much attended answers arrived at last. Two almost-complete specimens of Deinocheirus were found near the original one: they weren't found by the Polish scientists by misfortune.
This new material confirmed and debunked all the hyps above: Deinocheirus was really an ornithomimosaur, but displays a feature unknown in any other birdlike theropod: a sail that peaks over the hips, similar in shape to that of the carnosaur Concavenator. In 2014, its skull was found, which resembled that of the duckbilled hadrosaurs but with no teeth or bony crests. In the same year, new evidence emerged revealing that Deinocheirus had a thicker lower jaw than previously thought, and fish remains were discovered in one specimen's stomach. This suggested that Deinocheirus was an omnivore that mostly fed on ground level and aquatic vegetation and also ate small animals when it could.
Deinocheirus, in addition, became the largest dinosaur with evidence of feathers, as its tail showed pygostyles where feathers were attached, proving again than size did not rule out feathers, as the tyrannosaurid Yutyrannus had already demonstrated two years before — after all, modern elephants rhinos & hippos do have hair just like every other land mammal. Also it was revealed that the much smaller Beishanlong and Garudimimus were the closest relatives of Deinocheirus, forming the family Deinocheridae (whose Deinocheirus was originally believed the only member), thus putting the latter very close to true ornithomimids in the evolutionary tree.
Described officially in October 2014, the two new specimen were slightly bigger than the original one, and indicate that Deinocheirus actually was one of the biggest and tallest theropods ever: about 6-7 tons like a big T.rex, more robust than typical ornithomimosaurians, and one of the biggest animals of its fauna, the weight of a small titanosaurian sauropod like Opisthocoelicaudia, thus outweighing and potentially outmighting its possible predator Tarbosaurus, and living peacefully alongside the plant-eating Therizinosaurus. In short, Deinocheirus mirificus instantly went from being one of the biggest paleontological mysteries of the Twentieth Century to an animal whose appearance and lifestyle are well understood.
- Entry Time: 1980s
- Trope Maker: The mystery of its appearance
Gigant(ic) O(vi)raptor: Gigantoraptor *
Oviraptor relatives were small-sized like their group's namesake: the biggest, Anzu wylei, was only a bit larger than an ostrich. But this only of you don't count Gigantoraptor erlianensis. Discovered in Asia in 2007, this dinosaur, despite its name ("gigantic thief"), is not an overgrown dromaeosaur, but an overgrown oviraptorosaur.
The Gigantoraptor was 25ft / 8 m in length, and the only known skeleton was only a "teenager"; an adult would have been bigger, almost as big as the neighboring tyrannosaur Tarbosaurus, but still smaller than Deinocheirus, Therizinosaurus, or T. rex. The gigantoraptor had the anatomy of the classic oviraptorosaurs; if the oviraptorosaurian way of life has been hard to decipher (some hypothize to have them being originally herbivores, but re-evolving into pure carnivores), imagine what kind of headscratching Gigantoraptor caused. It's all cool, though: three, generally small-sized lineages of non-avian coelurosaurs have a few oversized members within their ranks: Deinocheirus the giant ornithomimosaur, Utahraptor the giant dromaeosaur, and Gigantoraptor the giant oviraptorosaur. On the other hand, tyrannosaurs and therizinosaurs include many gigantic species, while other coelurosaurs, such as the troodonts and alvarezsaurs, have none. But who knows? Maybe one day a Gigantroodon would be discovered
Together Deinocheirus, therizinosaurids & Gigantoraptor make a strange case: such overgrown birdlike theropods seem an almost only-Asian affair, and nobody knows why similar animals have never been found in North America except for the early therizinosaur Nothronychus — considering the strong similarity of the two faunas in the Cretaceous, which should even communicate to each other through the Bering landbridge. Maybe could the competiton with the almost-exclusively American Ceratopsids have prevented North-american birdlike theropods to reach larger size? And even this idea has problems, since we now know that there were a few ceratopsids in Asia, like Sinoceratops.
Like Therizinosaurus, only parts of the skeleton of the gigantoraptor is known for now. While Deinocheirus was an omnivore, and Therizinosaurus and kin were herbivores, Gigantoraptor has still no consensus regarding its diet. Its closest relatives show predatory adaptations and are known to have eaten small prey like lizards, and this is the most likely option so far, but considering that it's another giant "freak" nobody can be sure.
Despite being a very recent find, Gigantoraptor soon recevied some mild media attention, appearing in the early 2010s in paleo-documentaries, Planet Dinosaur and Dinosaur Revolution. The awesomely-named Gigantoraptor is on its way to becoming a minor Stock Dinosaur.
Other toothless birdlike theropods
Sorry, these ones aren't here. If you're looking for Garudimimus, Chirostenotes, Archaeornithomimus, Anzu, Conchoraptor, Rinchenia, Nomingia, Anserimimus, Sinornithomimus, and others, see here.
These dinosaurs were generally less-close to birds than the ones in the previous two folders. All lived earlier than them (except Archaeopteryx) in Jurassic or Triassic and not in Cretaceous, but they tend to be equiparated with them in media because of their slender shape and small size.
Cannibal or ancient Hero?: Coelophysis **
One of the first true dinosaurs to appear on Earth, Coelophysis bauri lived in Late Triassic North America 216-203 million years ago: fragmentary material suggests a near worldwide distribution lasting up to 188 mya, in Early Jurassic: ex. Coelophysis rhodesiensis lived in Africa, Coelophysis kayentakatae in North America. The latest two were once classified as "Syntarsus" or "Megapnosaurus", see here.
Described during the Bone Wars from some pieces of bone, today Coelophysis bauri is by far the most abundant early theropod in the fossil record. In the 1940s, a whole graveyard with hundreds of specimens was found in New Mexico; they're widely theorized to have died all together in a flood, though this is not certain. This was one of the first dino-graveyards ever found from the Triassic, after those of Plateosaurus found in Europe at the start of the century.
Coelophysis was a slim, fast-running dinosaur growing up to 10 ft/3 m, and weighing about 30 kg. Coelophysis looks like a fragile animal, with a narrow head, weak jaws with small pointed teeth, a long, stork-like neck (often incorrectly described as "snake-like" in popular dinosaur books), an elongated, thin body, and a long, slender tail. As an early theropod, Coelophysis was not very closely related to birds. For example, it had still a remnant of the fourth digit on each hand, and the presence of feathers is not proven. It it had them, they were surely "proto-feathers" or down-like structures, not modern-looking feathers. Still, it had bird-like features showing how far back in time the dinosaur-bird link goes. Its skull and hindlegs were similar to the more evolved theropods; its bones were hollow and had airsacs within them (Coelophysis just means "hollow frame"); and it even had a tiny wishbone, a typically avian trait, discovered only recently because of its smallness. Originally, it was accepted that non-bird dinosaurs were all wishboneless except for some birdlike theropods, e.g. the oviraptorosaurs and Archaeopteryx.
Coelophysis probably hunted down small prey, which it swallowed whole: lizards, dinosaur nestlings, fish, insects, proto-mammals, and whatnot. In the Triassic the top predator role was played by non-dinosaurian archosaurs like Postosuchus or Rutiodon, or larger theropods like Gojirasaurus. Coelophysis bauri is often described as a "successful underdog" which finally managed to outcompete non-dino archosaurs, anticipating the following domination of the dinosaurs in the Jurassic world. It is usually portrayed as a gregarious animal that lived and sometimes hunted in packs; although pack behavior is possible, pack-hunting is unlikely.
In many works it's said adult Coelophysises ate younger members of their own kind, or even their own offspring, during famines. This because bones found in the stomachs of adult specimens from the aforementioned "graveyard" in New Mexico were reported to belong to young Coelophysis, leading to the dinosaur being described as cannibalistic. Later studies from the 2000s have determined that the bones in question were animals of other species, possibly the small semibipedal crocodylomorph Hesperosuchus among them. This doesn't mean that Coelophysis didn't occasionally eat their own kind (crocodiles and eagle-nestlings do this after all); only that there isn't any fossil proof anymore.
Together with the large herbivorous Plateosaurus, Coelophysis is the dinosaur you're most likely to see in those documentary works portraying the Triassic Period, to show how the earliest dinosaurs looked — even though in Real Life there were many other dinos in the Triassic, some even more primitive: herrerasaurians like Staurikosaurus and "prosauropods" like Thecodontosaurus are two examples of the latter. In these works, the smaller Coelophysis is used to represent the very start of the dinosaur evolution, while the bigger Plateosaurus represents a more advanced/enlarged stage. An excellent example of all this is the first episode of the TV documentary Walking with Dinosaurs, in which the two animals are shown living together in North America: in Real Life only the coelophysis was North American, the plateosaur was found in Europe. In the show the coelophysis is portrayed cannibalistic during the worst part of the world-famine, but it's not said if the adult specimen eats one of its own youngs, or the chick of another adult individual.
Coelophysis has been far less common in fiction or other more popular media, since it is too humble-looking and generic by dino-standards to be interesting; the best-known appearance may be "Spot" from the 1974 children's television series Land of the Lost.
Dinosaurs as Pets: Compsognathus **
Compsognathus longipes was native to Europe 150 million years ago and lived alongside the famed "first bird" Archaeopteryx, in the same habitat made of small islands. Like the "Urvogel", it was one of the first dinosaurs described, in the same year as the latter. The first Compsognathus specimen was found in Germany in the Solnhofen site like Archaeopteryx. The second known specimen was found later in Southern France. Both skeletons are nearly-complete and still-articulated, again like Archaeopteryx, but UN-like it, haven't preserved imprints of skin. Though little-known, Compsognathus may have been the first non-bird dinosaur ever found from an almost-complete skeleton. Even less-known is the fact that some possible small round eggs have been found around the German specimen.
Only 4 ft long and weighing few kilograms, Compsognathus is the smallest Stock Dinosaur, not counting Archaeopteryx (and Microraptor, which has to be considered a real stock at this point). Like Coelophysis above, its frame was that of a generic small theropod with no sickle-claws on its feet. Compsognathus was more evolved and bird-like than Coelophysis however, with a shorter head and neck, a more compact body, and only three fingers on each hand. Old portraits in popular dino-books have typically depicted the "compy" with two-fingered T. rex-like hands, and sometimes even with fin-like hands: these errors were due to the incompleteness of the two known specimen's hands. More specifically, the German specimen led thinking it was two-fingered, while the French one led the bizarre "finned-hand" hypothesis. The two-fingered portrait has long been the most common in popular dino-books; the finned one, luckily, has appeared only occasionally.
If you hear about Compsognathus in documentary media, it will likely be for two things: its former record of "the smallest dinosaur", classically described as chicken-sized because its first-found German skeleton was only 2 ft long, but was from a subadult — the French specimen was 4 ft long; and its former status as "the closest relative of Archaeopteryx": despite similarities, the compy was possibly less close to birds than tyrannosaurs according to cladistic studies started in The '90s. Another compsognathid, Sinosauropteryx from Early Cretaceous China, shows downy covering around its skeleton but not pennaceous feathers; this was probably the same for Compsognathus, too.
Compsognathus has always been a regular sight in dino-books, in which is usually shown as a solitary hunter of insects, small vertebrates, and sometimes adult archaeopteryges: that last depiction is unlikely though, because Compsognathus was a rather fragile creature to kill a fully-grown "archaeo". It's curious, however, that the tiny Compsognathus could have been the actual top-predator of its insular world devoid of big predatory dinosaurs. Note that the Eustreptospondylus of WWD lived much earlier than Compsognathus in Real Life.
Even though its tiny size doesn't make our Compsognathus particularly menacing for humans, popular media have equally managed to transform it into a "miniature terror". In 1997, The Lost World: Jurassic Park made it a deceptively cute critter which attacks in huge packs and kills humans with a paralytic bite. While Compsognathus may have been cute, there is no indication of social behavior in the two known fossils both found isolated. Furthermore, its thin jaws and peg-like teeth were strictly adapted to catch and swallow small prey, and not to tear tough skin like the jaws of other small theropods. Finally, the fact that the original German specimen's stomach cavity contained a small lizard (namely, Bavarisaurus) would tend to support this even more.
Jurassic Coyotes?: Ornitholestes & Coelurus *
Ornitholestes should not to be confused with the similarly-named Ornithomimus. Both were slender animals, but the "lestes" was the same length/size of the Real Life Velociraptor (2 m/7 ft long and weighing about 15 kgs), while the "mimus" was notably bigger, 3.5 m/12 ft long about 150 kgs. The "lestes" lived alongside the giant dinosaurs Allosaurus, Stegosaurus, Apatosaurus, Diplodocus, Camarasaurus, Camptosaurus, and Ceratosaurus, the Ornithomimus-sized Dryosaurus (still too big to be its prey when adult), but also with a nigh-identical, only a bit smaller (1.8 m/6 ft) theropod named Coelurus, not to be confused with Coelophysis, in Late Jurassic North America 150 mya — well before the Late Cretaceous Ornithomimus, but well after the Triassic Coelophysis.
Within their habitat, Ornitholestes and Coelurus arguably played the role of the small cunning predators, while Allosaurus and Torvosaurus were the top predators and Ceratosaurus was between the two extremes. Although there are no evidences, their preys were possibly lizards, mammals, frogs and insects, and sometimes, also ate the eggs and hatchlings of bigger dinosaurs. In the Time of the Titans episode of Walking with Dinosaurs we can see some Ornitholestes behaving in such a way. In many paleo-artistic works Coelurus and Ornitholestes have been shown behaving like jackals, foxes, or coyotes, tearing chunks of flesh from the kills of Allosaurus or Ceratosaurus and fleeing safely from these larger predators.
Ornitholestes hermanni, the only known species of its genus, was found about 30 years later than Coelurus fragilis ("fragile hollow tail"), also the only-known species of its own genus: the latter was found in the Bone Wars by Marsh, and its name was the inspirer for the few-years-later-discovered Cope's Coelophysis bauri ("Baur's hollow form"). Ornitholestes was found at the beginning of the 20th century 20 years after the "Wars": its name, bird thief, was given because it was though a specialist predator well-adapted to grasp first bird Archaeopteryx with its prehensile hands. Such a thing would not technically be impossible, the two being contemporaries only, the proto-bird lived in Europe, together with Compsognathus.
In many modern portraits, Ornitholestes (but not Coelurus) used to be shown with a horn-like crest on its nose, seen even in Walking with Dinosaurs; however, we know now that it didnt have this feature. Coelurus skull is unknown apart from the thin lower jaw with small teeth. Ornitholestes had a more compact body-build and more robust jaws and teeth than Coelurus; these two Non Identical Twins has arguably less-conspicuous feathers than the dromeosaurids, more similarly to a "compy".
Walking With also added some speculative erectile quills on the ornitholestes' neck: though not demonstrated, these might be possible, especially as Ornitholestes has recently been classified as a bird-like maniraptoran in some analyses, albeit still of uncertain placement within the clade: maybe a distant relatives of dromaeosaurids and troodontids. The link with maniraptors is further reinforced by one detail: Ornitholestes had a smallish retractable toe similar to that of deinonychosaurs and early birds, even though almost-every pictures (WWD included) show it with generic bird-like three-toed feet. Coelurus is not known to have had the claw in question (its feet are unknown), and every picture of it shows it with generic feet. Like Coelophysis, some have depicted these two predators as pack hunters, but as one single sure specimen is known for both, this could be unlikely. Other portraits have shown them as among the preys for Allosaurus or Ceratosaurus — thus not proven this is possible, considering that sometimes modern lions, wolves and tigers do feed on smaller carnivores in the wild.
- Entry Time: 1999
- Trope Maker: Walking With Dinosaurs (the Time of the Titans episode, only the book for Coelurus)
Two of the Earliest Dinosaurs: Herrerasaurus & Staurikosaurus *
Thanks to dino-books and documentaries like those of the Walking with Dinosaurs series, several people have become conscious about the existence of Coelophysis, which has become the forerunner of the dinosaur world. However, some carnivorous dinosaurs lived even before it; but are so ancient, that could not even be real theropods. In Triassic world, dinosaurs still were not so differentiated each other, and the familiar Coelophysis shape was shared by several other animals, obviously with some degree of variation. Herrerasaurus, Staurikosaurus and Eoraptor are the three most classic examples. Together, the first two form their own dinosaur subgroup, the Herrerasaurians, whose namesake Herrerasaurus is the official prototype.
Their shape was typically theropodian, but the skeleton was more archaic and less bird-like; both Herrerasaurus and Staurikosaurus had five digits in their feet, more similarly to sauropodomorphs like Apatosaurus or Plateosaurus than to neotheropods note , which have only four like most modern birds as well. Also their pelvis were unique. This bony-puzzle was responsable of many headaches among paleotaxonomists: Staurikosaurus and Herrerasaurus, indeed, have been variably classified as true theropods, true sauropod-relatives, generic primitive saurischians, the only dinosaurs neither-saurischians nor-ornithischians, and in the most extreme case, even non-dinosaurs at all!
Herrerasaurus was discovered in the 1960s in what is now Argentina. It was a bit longer than a Coelophysis (3-4 m) but much more robust, with a larger, stronger head and shorter neck, almost-recalling more a miniature "carnosaur" than a "coelurosaur" (in the former senses of these words). Herrerasaurus was arguably a more powerful predator, hunting relatively larger animals than those hunted by the coelophysis: possible preys for it could have been the beaked rhynchosaurs, mammal-ancestors, and small-sized dinosaurs like Pisanosaurus. But Herrerasaurus was still small compared with other early carnivorous dinosaurs like Dilophosaurus, and arguably retreated against giant prosauropods like Riojasaurus (even bigger than Plateosaurus, being 11 m long) or the 7 m-long carnivorous dinosaur-relative Saurosuchus. Some Herrerasaurus remains were put in their own genuses, "Frenguellisaurus" and "Ischisaurus". Herrerasaurus was found in Ischigualasto, the formation in Argentina in which it and other dinosaurs & non-dinosaurs have been found — the complete name of this dinosaur is indeed Herrerasaurus ischigualastensis.
Discovered in 1970 slightly after Herrerasaurus, Staurikosaurus shared the same body-structure of the latter (with some differences) but unlike Herrerasaurus was smaller than Coelophysis, only the size of the real-life Velociraptor: 2 m (6 ft) long. It arguably hunted smaller preys, perhaps young rhynchosaurs or smaller mammal-ancestors. Staurikosaurus was originally put in its own family, the Staurikosaurids (Herrerasaurus was put in the Herrerasaurids); among primitive traits of both they had only two vertebrae in their sacrum (like modern reptiles), not four or five like the typical dinosaurs and birds.
Staurikosaurus is also one of the most poetically named dinosaurs, Southern Cross lizard: it could be renamed the "Starry Dinosaur" for this. It has been for several decades the only dinosaur found in Brazil, and Brazilian flag shows just this constellation. However, the staurikosaur was found in the southernmost part of Brazil, just near the boundary with Argentina. Its complete name is Staurikosaurus pricei; one alleged relative, "Teyuwasu", has recently been reclassified in its genus.
Together, Staurikosaurus and Herrerasaurus have long disputed the title of the first/most primitive dinosaur ever appeared on Earth, with some books preferring one and others preferring the other. Anyway, among the numerous hypotheses made in the eighties, some paleontologists went to claim herrerasaurians were the ancestors of all the other dinosaurs: now this hypothesis is totally discarded, since they had their specializations on their own, included some evolved traits (ex the shape of their pelvis). Monotremes (platypus & echidnas) are the most primitive mammals today, but this doesn't mean they are the ancestor of marsupials and placental mammals after all, and they too have specialized traits (electric sensors, or venom-spurs in the case of the platypus) that lack in the other living mammals.
- Entry Time: undetermined
- Trope Maker: their former status of "the First Dinosaurs"
"Dawn Thief": Eoraptor *
Discovered in Argentina in 1993, the same year of the first Jurassic Park film, Eoraptor lunensis means dawn robber from the Moon valley from Valle De La Luna, the formation it was dug out (another astronomical-named dinosaur like Staurikosaurus).
Its describer, Paul Sereno, first found its skull and believed was from a basal archosaur; then, the almost-complete and still-articulated skeleton fas found, showing it was a true dinosaur, but even earlier than the two traditional "most basal dinosaurs", the herrerasaurians Staurikosaurus and Herrerasaurus, both found in South America between the sixties and the seventies. Its discovery suddenly seemed to solve the rivalry between them for the Whoa, the very first dinosaur ever appeared! title. When was described, Eoraptor was thought more primitive than both; however newer studies don't always agree with this. 3-4 ft long, not bigger than a Compsognathus, Eoraptor shared with herrerasaurians some skeletal features resembling non-dinosaurian archosaurs; it too, like them, was thought neither saurischian nor ornithischian, but a more basal animal in the middle between true dinosaurs and other dinosauromorphs such as contemporaneous Lagosuchus, also found in South America twenty years before.
Since then, Eoraptor has been perhaps the most celebrated among all the supposed first dinosaurs: maybe because was discovered just at the time Jurassic Park came to audiences — and the fact that it received the now-familiar suffix -raptor could have done its bit, too. Since then, our dawn robber has gained much attention in non-fictional media, also being object of some degree of sensationalism. Several awesome nicknames were invented, from the first terror to The father of all killer dinosaurs. But Real Life Eoraptor wasn't so fearsome, really: it was a tiny, gracile dinosaur, which could even become a meal for a hungry Herrerasaurus or even a Staurikosaurus, which were contemporary to it but bigger - Herrerasaurus reached 12 ft of length, Staurikosaurus 7 ft. Researches made after the Turn of the Millennium suggested its differentiated teeth were more probably from an omnivorous rather than carnivorous animal. Science Has Marched On Even More in year 2011, and one study has found Eoraptor to be an extremely unspecialized sauropod-predecessor, thus closer to Plateosaurus than to Coelophysis; most recent researches still consider it a proper theropod (in the widest sense). It's highly probable that the debate has yet to be ended.
The study about which dinosaur really deserves the common-ancestor-of-all-dinosaurs title marches on relentlessly, and now there are many other contenders found and/or described in the 2000s and 2010s other than the most traditionally known. Astonishingly, many of them come from South America as well, to the point South America could be renamed the cradle of the dinosaur kind at this point. An exception is Nyasasaurus (arguably the very first dinosaur, but initially believed a prosauropod), found in Africa in 1956 but described only in 2012. Other exceptions are the North American Chindesaurus (possibly a herrerasaurian), the Indian Alwalkeria (possibly non-dinosaurian and/or a chimaera), and the Chinese Lukousaurus (variably classified from a ceratosaurian to a crocodylomorph). The most basal dinosaur was the common ancestor of Saurischians and Ornithischians, and almost certainly was more similar in anatomy to the former than to the latter: among archosaur groups saurischians are less-derived than ornithischians, at least if you count the structure of the jaws and the pelvis. Some basal saurischians make together the Guaibasaurids: these saurischians were extremely generic and unspecialized dinosaurs. Their external shape was really in the middle between a small theropod and a basal sauropodomorph, not deceptively theropodian like herrerasaurs or Eoraptor. The namesake Guaibasaurus was the first discovered; then, the mythical-named Saturnalia note from Brazil, which was initially believed the first prosauropod. In the second half of the 2000s scientists decided that both dinosaurs were too basal to be either theropods or sauropods, and put together in the same family, Guaibasaurids. Now they are often considered very basal sauropod-predecessors, though this, too, may still change. With their unspecialized traits, guaibasaurids were almost surely omnivorous creatures; indeed, a third member found in 2009 has received a meaningful name: Panphagia, eat-all.
- Entry Time: 1998
- Trope Maker: The Lost World (film)
Other small theropods
Sorry, these ones aren't here. If you're looking for Guanlong, Scipionyx, Masiakasaurus, Elaphrosaurus, Proceratosaurus, Procompsognathus, Noasaurus, Sciurumimus, Juravenator, Saltopus, "Protoavis", and others, see here.
As easy as it is to forget, birds are dinosaurs as well. Specifically, birds are members of the maniraptoran clade, which also includes the aforementioned dromaeosaurs, troodontids and oviraptorosaurs. Yes, that means that dinosaurs are technically not extinct! These contain the only Cenozoic dinosaurs on this list.
Symbol of Man's Folly: the Dodo ***
One of the most recently extinct stock dinosaurs (in a technical sense, anyway), having been wiped out before 1700 in full Modern Age, the dodo (scientific name: Raphus cucullatus) was a turkey-sized flightless pigeon that lived on the isolated island of Mauritius. The pigeons it was descended from almost certainly flew to the island, but because there were no land predators, the dodo evolved secondary flightlessness, no longer needing the luxury of flight—which may have been an evolutionary mistake, considering what happened when humans and their pets showed up. Its diet likely comprised of fruit and seeds, as well as possibly insects.
The circumstances of the dodo's extinction are commonly misinterpreted. The most common explanation was that they were simply unable to comprehend that humans were NOT friendly and thus were hunted for their meat until they all died out. In reality, while it is likely that these birds were a little too brave for their own good (many modern birds on Mauritius still can't take the hint), they certainly weren't helpless creatures—their beaks were very large and sharp and reportedly were capable of delivering painful nips if the dodos got agitated. Additionally, the meat of the dodo was said to have been very tough and oily, making it very unpalatable for human consumption. It is now thought that the demise of the dodo came along because of the invasive species brought into the island—rats and cats ate the babies and eggs while pigs and dogs ate the adults. In addition to the previously mentioned flightlessness and possible Fearless Fool status, dodos were very slow breeders who couldn't repopulate faster than invasive predators were eating their young, so it wasn't long before they all disappeared.
Dodos are frequently thought of as having been stupid creatures, to the point that we have a trope for this portrayal and a proposed origin for its name was a Dutch word meaning "simpleton". We now know that dodos were no more or less intelligent than any other pigeon and that because it was a pigeon, and not an odd chicken/turkey as often believed, a more likely origin for its name was the sound it made, which most likely sounded like a soft "doo-doo".
The dodo had a cousin on a neighboring island called the Rodrigues solitaire—which sadly also went extinct—and its closest living relative is the Nicobar pigeon. Other extinct birds from the Mascarene islands (Mauritius, Reunion, Rodrigues etc.) included a giant ground-dwelling parrot, a harrier, a sparrowhawk-like owl, a sundry assortment of flightless rails, and even a flightless ibis, the latest one was once believed a dodo relative, the "Reunion solitaire". Together the dodo and the two solitaires, the real and the ibis one (note that solitaire = lonely in French) used to make their own family of birds, the Raphids: modern taxonomy put the dodo and Rodrigues' solitaire in the same family of all the other living or extinct pigeons/doves, the Columbids.
The dodo is probably the most famous extinct animal that didn't come from the Mesozoic or the Pleistocene Ice Age. It comes from the Modern History, to the point that a notable euphemism for death or obsolescence is "going the way of the dodo" or "dead as a dodo". On a more serious note, the dodo's extinction is one of the things that has motivated humankind to try and be more environmentally minded—after all, we were able to drive this innocent, goofy-looking bird to extinction, who's to say we won't end up wiping out more species? Sadly, not everyone got the hint, not to mention we lost many species before the dodo too, for example the giant running-birds Moa from New Zealand and Elephant-Bird from Madagascar (see below).
The dodo's fame probably started with Alice's Adventures in Wonderland, when an anthropomorphic dodo appears among the animals Alice encounters in Wonderland. The Dodo in the book is said to be an Author Avatar for Lewis Carroll. Dodos have appeared all over the media, usually depicted in the outdated, fat, stupid waddling birds portrayal, as opposed to the thinner and more bold birds that we know they were now. They'll often be put into a post-dinosaur world for comic relief—for example, in Ice Age where the dodos are depicted as possessing almost suicidal stupidity. Most media will also forget that the dodo is a pigeon. Regardless, the dodo will almost never be depicted as a Prehistoric Monster, unless it's mutated or something, and even then it will be seen as a joke rather than a threat, as was the case in Primeval.
- Entry Time: 1865
- Trope Maker: Alice's Adventures in Wonderland
The Penguin of the North: the Great Auk *
Here's another recently-extinct bird that is rather common in popular paleo-sources, though less in more mainstream media like all the birds of these two folders. The Great Auk's scientific name is Pinguinus impennis ("featherless penguin", but was feathered!).note This is not a mere coincidence however: indeed, the word "penguin" originally just indicated this bird, which people used to see in the Northern Atlantic coastlines before the spheniscids (aka the commonly-intended "penguins") were actually discovered in the XVI century, during the first explorations of the Southern Seas. In other words, Polar Bears and Penguins was once Truth in Television.
The Great Auk was a relative of modern puffins, murres, and razorbills: that is, it was a member of the Alcids, the "Auk family", and was also related more distantly with seagulls, terns, woodcocks, plovers, curlews, jaegers, and so on (all of them belong to the bird-group named Charadriiformes). It resembled a modernly-intended penguin because of its erect pose, black & white plumage, and palmated feet, but mainly because it was flightless unlike the other modern auks, with very reduced wings unapt to fly bt apt to swim underwater - its swimming style is uncertain: probably it used both the wings and the feet, unlike true penguins which use mainly the wings. The great auk had a characteristic black bill, with parallel keratinous crests on the base of it - modern auks also often have striking beaks, expecially the puffins with their large colored bills (they called or nicknamed "sea-clowns" in some languages just thanks to this). It was large, too: 3 feet tall and weighing several kilograms, much more than still-living auks, about the size and weight of a King Penguin, but still smaller than an Emperor Penguin (the biggest living spheniscid) or the mesozoic toothed Hesperornis.
Sadly, this large specialized seabird was depleted by us humans during the XIX century thanks to overhunting: the last two specimens were killed in year 1844, two centuries later than the tropical island-dweller dodo. Indeed, all around the world, flightless birds have revealed to be the most vulnerable to extincion, expecially those living in insular worlds — not only dodos, elephant birds, and moas, but also less-familiar groups like the dodo-like Moa-Nalo ducks in Hawaii. The flightless or poorly-flying Takahe and Weka rails, the Kakapo parrot, and the Kokako songbird all of New Zealand, and the Laysan duck of Hawaii managed luckily to escape this fate Just in Time, but are still endangered.
Unlike other historically extinct animals like the iconic Dodo and the cattle- and horse- ancestors Aurochs and Tarpan (painting in caves and ancient literature), the Great Auk is mentioned mainly in modern scientific or educational works. Its striking penguin-like look would make it appearing even cuter than the flightless pigeon, while its menacing-looking large uncinated bill and bald face that resembles a bit those of some raptor birds. Its only notable appearance in fiction was in Charles Kingsley's novel The Water Babies, where one tells the tale of the extinction of its species.
Upsetting Massacres: the Passenger Pigeon & the Carolina Parakeet *
These small birds are surely the least exotic-looking among the extinct birds listed here, but are famous because of the story that led them to their disappearing in the end of the XIX century.
The passenger pigeon (Ectopistes migratorius), unlike th dodo, was a totally normal-looking pigeon (pigeons and doves make together the order Columbiformes) who used to fly in huge flocks in North America. Before its demise it was one of the most common birds here, with millions of specimens that, it was said, "obscured the sky when flying in group" almost like a living cloud. Some even declare that the pigeon was once the most abundant bird in the world, but this is not demonstrable.
Its appearence and size were those of a typical wild pigeon, with bluish-gray and brown feathers, and emitted sounds very similar to those of most pigeons & doves. While one could assume that it was a very popular game among hunters and nest raiders, and its extinction was not due to insularism and flightlessness. The Passenger Pigeon was however an ecologically very strict bird, which lived only in specific niches, thus more vulnerable to overhunting than other less-common but more adaptable birds of the USA like wild turkeys or bald eagles. The only passenger pigeons you'll see nowadays are preserved specimens in museum exhibits, science archives, and the like.
In Fictionland, this bird is very unlikely to appear because of its generic dove-like look. Indeed, it is notable mainly for its absence from popular American period pieces set during the time it was abundant (imagine Gone With The Wind with flocks of pigeons dotting the landscape!) Another bird that inhabitated the USA since about a century ago was the Carolina Parakeet, one of only two North American parrots (the other is the now-endangered Thick-billed parrot) known in historical times before its extinction. It was another ecologically-strict species of flying land-bird that was very abundant once — some say even more numerous than the passenger pigeon itself in certain places, but it too was destroyed by overhunting. Like modern parakeets, it very likely could be kept as a pet and a human-voice imitator if alive today. Like the pigeon, is very unlikely for it to appear in fiction because of its normal-parakeet look— in fact, it was almost identical to the Jenday parakeet of South America.
- Entry Time: undetermined
- Trope Maker: Cultural fallout from their extinction
Giraffe-Bird: the Giant Moa *
Giant dinosaurs were not exclusively an only-prehistoric affair: two really large birds have lived in human historical times: the Moa and the Elephant Bird.
Both were Ratites, aka flightless birds related with ostriches, rheas, cassowaries, emus, and kiwis. Moas ("Moa" is a Maori word), also called Dinornithines from their best-known genus, Dinornis, "terrible bird", lived in New Zealand like the more popular icon of this country, the kiwi. The biggest moas, obviously, are the most shown in media, expecially Dinornis maximus (maximus = "the biggest"): others, though, were fairly smaller, like Emeus crassus, lit. "fat emu", or Anomalopteryx, lit. "strange wing". D. maximus reached 3.5m /12ft in height, much taller than the tallest living ostrich (9 ft at the most), and were also more heavily-built, with stocky legs and massive body: they could have weighed 400 kg or more - ostriches at the most weigh 150 kg.
According to semi-fossilizied remains, moas' plumage was rather similar to a kiwi's in texture and color, and like the latter they had no visible tail. They reduced their wings to an extreme, even more than the kiwi itself note : moas were totally devoid of them, even in their skeleton (except for the remnants of shoulder-girdle and humeri), making them one of the most extreme cases of reduction of the anterior limbs among theropods.
Giant moas were by far the biggest New Zealand animals of their time: they had small heads and bills, long giraffe-like necks, and were probably slower and more strictly herbivorous than modern large running birds (ostrich, emu, rhea, cassowary), which also eat insects or small invertebrates other than plant matter. Moas had no potential predators that could have killed them, except for two: the Haast's Eagle which preyed upon smaller species & the juveniles of the biggest ones, and more importantly, humans. The ancestors of the Maoris first colonized the distant New Zealand archipelago during the european Middle Ages, probably heavily hunted them, and/or gathered their eggs, or set fires, unwillingly eliminating the few still-living dinornithan species. Since today, Maoris have telled stories and legends about these birds their ancestors had the fortune to see in life. Kiwis managed to survive, but then, European colonizers reached the islands introducing several household mammals in the wild like cats, rats, pigs, dogs, weasels etc, which almost managed to delete the animal they later chose as their national symbol.
In modern pop-culture the moa could be associated to the so-called "terror-birds" because of its size and shape, even though it has not been depicted as a voracious predator unlike the Diatryma (Gastornis), but usually more as a Gentle Giant, because of its smaller head and round bill and its more overall inoffensive look.
- Entry Time undetermined
- Trope Maker Its size and Maori legends
Huge Eggs: the Elephant Bird *
The Elephant Birds have a particularly apt name. They are more properly called Aepyornithines — the latter name meaning "lofty bird": the two most portrayed species are, again, the biggest ones, Aepyornis maximus & Aepyornis titan (recently renamed Vorombe titan).
Elephant birds lived in Madagascar, the large island of the Southern Emisphere close to Africa whose most famous animals are the lemurs - incidentally, not far away from the much smaller Mauritius, the former home of the equally much smaller dodos. These malagasy birds shared with moas a similar outward appearence but their skeleton was rather different. The two kinds of "giants of the southern islands" were not strictly related to each other (moas are believed closer to kiwis than to aepyornithines), but both shared the same similarly-reduced "wings".
Elephant-birds, however, were even more massively-built than the Giant Moas, with huge body and very stocky "elephant-like" legs — hence their common name. The biggest ones were maybe the largest/heaviest birds of every time, but still less-tall than giant moas because of their shorter neck. They resembled a bit overgrown emus or cassowaries — while dinornithines, being more slender, looked more like true ostriches or rheas. Both dinornithes and aepyornithes possibly behave the same way, and the latter were probably mainly-herbivorous as well.
During the first explorations of the Malagasy island made by European navigators after the XVII century, they found the fragments of some truly gigantic eggshells, belonging to eggs twice the diameter of the biggest modern eggs (those of the ostrich, that are about one foot of diameter), and still-today the biggest known eggs of every dinosaur/land animal known.note Later, other semi-fossilized remains were found of aepyornithines, the biggest of them revealed being among the heaviest birds ever, if the heaviest: maybe more than 540 kg, like a small cow. Only the biggest dromornithines (another group of extinct flightless birds, this time from Australia) could have rivalled them in mass. The Elephant Bird gives its name to one of science-fiction british writer Herbert George Wells' tales: The Aepyornis Island, publicized the 27 december 1894. Wells in his novels cites at one point also the Dodo, the Great Auk, and a moa of the genus Anomalopteryx.
The extinction of the "elephant bird" is still unclear: they hadn't natural predators when adults unlike the moas, and only humans could have driven them to their fate. There are different hypotheses about the real cause of their demise. Hunting? Introduction of foreign species? Egg gathering? Even the precise period of their disappearance is uncertain. Some have speculated, however, that the mythical Roc bird was inspired from ancient Arab sailors who saw these birds alive in Madagascar in the Middle Ages. This is controversial though, since the Roc, unlike the elephant-birds, used to be portrayed like a giant flying bird of prey. It's speculated that aepyornithines were mistaken for baby Rocs, with the Malagasy crowned eagle perhaps being (by misjudging their size and distance in the air) mistaken for the adults Rocs. A truly-prehistoric bird that actually resembled a bit the roc in shape and size is Argentavis, the "Argentinian Bird", living about 8 mya.
- Entry Time: 1894
- Trope Maker: Its size and its possible relation to the Roc myth
Dinosaurs continued to Rule: Gastornis or "Diatryma" *
Long-standing paleo-fans will remember the name "Diatryma" for sure: that large, flightless, large-headed predatory bird who used to hunt the small "horse" Eohippus in so many paleo-artistic depictions placed in Eocene North America. Well, now poor "Diatryma" seems having definitively disappeared... but luckily, it hasn't, as such: it's simply changed identity. Now we have to call it Gastornis (a far less awesome name, we've got to admit, but... never mind). Whatever name should be used, this has always been one of the most enigmatic extinct animals of all.
Since its discovery in the XIX century - it's known not only in North America but also from Europe - scientists have guessed if Diatryma was a carnivore, an omnivore, and an herbivore. The predatory view ultimately won the context for more than a century, but as recently as in The New '10s it was shown by experts that it wasn't probably carnivorous at all. The problem is, its beak was strong but not hooked like an eagle's, and its body frame was stocky, seemingly slow-moving, like an elephant bird. Thus, it probably was a mainly-herbivorous omnivore that used its bill to crack nuts and cut vegetation, making erroneous the Bizarro World portrayal in Walking with Dinosaurs and the whole paleo-artistic tradition, where these birds are shown ruling mammals of every kind (and not only the "ur-horse" Eohippus).
However, this does not mean automatically the diatryma/gastornis was the Gentle Giant recent news articles claimed it was. Ostriches, emus and cassowaries are mainly herbivores too, but they're also some of the few birds that have been known to kill people for self-defense - ostriches and cassowaries have even one enlarged claw in their foot, like a dromeosaur. Gastornis hadn't such weapon, but not only grew to their size, but it also had a much more powerful beak that would've been useful for fighting off the land-dwelling crocodiles like Boverisuchus or the giant constrictor snakes, that were the true dominant predators of the early Cenozoic. Regardless, Gastornis was definitely a literal and figurative giant in its forested world note , 40 million years ago: while mammals were still mostly small, except for some pantodonts and mesonychians, some birds grew to large size.
In several depictions (Walking With Beasts included) Gastornis/Diatryma is shown with a naked skin-colored face or even neck making it similar to an ostrich/turkey or a vulture, underlining both its flightlessness and its alleged carnivory and fierceness; actually the texture of its plumage and its overall coloration are totally unknown, since soft tissues have not been found yet. You might also see it wingless in illustrations, while its skeleton shows small wings possibly covered with feathers and visible externally, but useless for flying like those of the Dodo or the Great Auk.
- Entry Time: start of the XX century
- Trope Maker: The paintings of Charles R. Knight; Walking with Beasts popularized in year 2001 the new name Gastornis
The true "Terror Birds": Phorusrhacos & Titanis *
With the Phorusrhacids, on the other hand, we did never have doubts this time: thanks to their light weight and slender running legs, they surely were active hunters of small mammals. And with their strongly hooked, very eagle-like bills, they probably did not always swallow their prey whole. Because of their beak, great size, and flightlessness, they could also be renamed "the Giant Running Eagles".
They were once thought to have an one clawed finger protruding from each of their tiny wings, for uncertain purpose. This is not so strange as one may think: there are also living birds with this feature, the most notable being the two-fingered young Hoatzin of South America. However, it was later discovered that their living relative, the seriema (Cariama cristata) has similarly-shaped wings and lacks wing claws, making these fingers unlikely. Among the most amazing-looking among all prehistoric birds, phorusrhacids have recently been nicknamed terror birds in pop-documentaries, for example, Prehistoric Park, in which they have however a minor role, and are portrayed as underdogs of the sabertoothed cats. In reality, phorusrhacids were probably powerful enough to fight off a Smilodon from their carcasses, and some think that smilodonts are usually believed "superior" than terror-birds only because they're mammals like us, but also because they survived longer in South America than the birds, but both kind of predators lived together in Pleistocenic North America before us humans appeared.
South America was the land all phorusrhacids originated from, and they have left a legacy in modern south-american prairies: the closely-related seriema and the smaller "Chunga" bird are medium-sized birds able to fly but mainly ground-dwelling, whose shape and arguably habits resemble miniaturized "terror birds". The not-related African secretarybird (Sagittarius serpentarius) is similar to the seriema as well, but is actually a true bird-of-prey related with eagles and hawks. The prototypical South American Phorusrhacos (often misspelled "Phororhacos", "Phororhacus", "Phororachus" and similar) lived in the Miocene about together with the aforementioned "roc" Argentavis and the sabertoothed marsupial mammal Thylacosmilus, before hominids and true sabertoothed cats appeared. The North American Titanis walleri (lit. "the Waller's titanic one") lived in full Ice Age. They are the two most portrayed species of the family: among the others, Kelenken was found only recently in Argentina, in 2007, but is now the largest known phorusrhacid. It lived earlier than Titanis, about the same time of Phorusrhacos. Another less-known members were less-tall but more robustly-built than them, ex. Brontornis, "thunder bird".
Despite being only distant relatives, and the aforementioned Science Marches On, expect Gastornis to be lumped in or confused with the true "terror birds" anyway. In fact, Gastornis was actually more closely related to ducks and chickens than to the Phorusrhacids, which in turn were closer to birds-of-prey, parrots, and songbirds according to the most recent molecular research. Once, both of these ancient kinds of ground birds were classified in the artificial Gruiforms assemblage which included cranes, rails, and bustards among the others. The most notable appearance of the terror-birds in non-documentary fiction is in 10,000 BC, where they fill the role of raptors. Never mind that, even if species like Titanis did live alongside early humans, they never made it to Egypt where the film appears to take place.
- Entry Time: 1912
- Trope Maker: The Lost World (novel)
Giant Toothy Seabird: Hesperornis *
Hesperornis ("western bird") and Ichthyornis ("fish bird") have traditionally been the two most commonly depicted Mesozoic birds in books (not counting the superfamous "missing-link" Archaeopteryx of course), both from Late Cretaceous North America unlike the latter which was Late Jurassic and European.
Both were discovered during the Bone Wars by Othniel Marsh. Since Hesperornis is cooler, here we'll mention it first. Hesperornis, whose original species is called regalis, "royal" in Latin, lived in the same habitat in which pteranodonts, tylosaurs, elasmosaurs and archelons roamed: the shallow inland sea which used to cover the American Midwest at that time, dividing North America in two parallel strips of land running from the Arctic down to the south. Despite living in such an early period, Hesperornis was already a very derived bird. 6 ft long (the size of a human, taller than an an Emperor penguin and much bigger than the Great Auk), it was flightless like them: vestigial wings with only the humeri in the skeleton just like in the moas, short splayed legs for swimming like the auk, a long neck like a stork, and a long straight beak like an anhinga, for some the modern bird that incidentally resembles the hesperornis the most in behavior and external look. But unlike all them, it had small true teeth.
This critter spent most of its life in water but returned on land to lay its eggs, like a typical modern seabird. Once, indeed, the hesperornis was shown as a sort of proto-penguin, and with an erect pose; we know now its legs were too weak to support its body in the manner of spheniscids or alcids, and the animal is now portrayed as more similar to modern grebes and loons. It was often depicted with the typical palmated feet like a loon, but it's more likely it had flattened toes like a grebe or a coot (a water rail). Similar to Hesperornis but smaller, Baptornis ("diving bird") also lived in the same shallow seas.
In Primeval, Hesperornis appears as an aggressive but non-malicious creature that kills a plumber after its anomaly appears in someone's flooded basement. It's portrayal there is probably one of the worst of any extinct bird to the point that the creature designers had it featherless (every real ancient or modern bird has feathers, even the apparently-featherless penguins) and standing upright like in the ancient classic illustrations.
- Entry Time: the 2000s
- Trope Maker: Primeval
Toothy Flyer of the Mesozoic: Ichthyornis *
The much smaller Ichthyornis dispar lived in the same age and habitat of Hesperornis, but this time we're faced with a sorta toothed, long-billed proto-seagull. This is the only flying bird encountered in the Useful Notes about stock extinct birds apart of the Passenger Pigeon and the Carolina Parakeet; flightless birds, either large or small, land- or water-dwelling, seem to be the favorite ones in media — maybe because of their oddity of not-flying. But some spectacular flying birds did exist in the Mammal Age, like the "giant condors" Argentavis and Teratornis, and the "giant albatross" Osteodontornis and Pelagornis: some had the wingspan of a giant pterosaur like Pteranodon, and possibly even heavier than it.
Returning to the less-striking ichthyorn: its lifestyle was arguably similar to modern flying waterbirds, catching fishes in flight like modern terns, or maybe diving under the sea to pursue them like modern boobies. You can almost be certain that if pterosaurs are involved, these little guys will be depicted as pests who like to steal food from them, originated in year 2000 from the Disney's Dinosaur film: this behavior was possible, but has never been proven. In Real Life both ichthyos and hesperos sometimes fell prey to large marine reptiles, as shown by remains of stomach contents, ex those of mosasaurs.
Despite their primitive toothed skull, the remaining skeleton of both Ichthyornis and Hesperornis was almost full birdy at this point note . If alive today, apart of their teeth they'll be easily taken for components of modern avifauna. In some artistic works, both Hesperornis and Ichthyornis are depicted as black and white like modern gulls or penguins, but their real coloration is totally unknown.
While these two do feature prominently in dinosaur books and sometimes documentaries (Hesperornis, for example, was the token prey animal in Sea Monsters and Ichthyornis got a bit part in Dinosaur Planet as a scavenger), their presence is rare in more mainstream media, presumably because, besides their teeth and Hesperornis' large size, they don't have a lot of cool points. That hasn't stopped folks from trying to portray the two stock Mesozoic birds, for better or worse. An Ichthyornis, creatively and perhaps fittingly named "Ichy" appears as a one-shot villain in the fourth Land Before Time movie, accompanied by an equally villainous crocodilian Deinosuchus. Ichthyornis also cameos in Dinosaur, erroneously depicted as duck-like creatures rather than seagull-like, and are among the many factors contributing to the start of the movie when they attack the mother Pteranodon carrying Aladar's egg, causing her to drop it.
- Entry Time: 2000
- Trope Maker: Disney's Dinosaur
The True Roc: Argentavis *
Historically-extinct Elephant-Birds or Aepyornithes of Madagascar have often said to have been the inspirers of the myth of the Arabian Nights flying Roc Bird: but in reality they were huge flightless birds looking like an upscaled ostrich. The Roc title should pertain more aptly to another, this time fully prehistoric, flying bird-of-prey: Argentavis magnificens, aptly "magnificent argentinian bird".
This has traditionally been the most famous flying bird among those living after the dinosaurs, while the most known feathered flyer among the Mesozoic full-birds is the much smaller toothed Ichthyornis above. Along with giant pterosaurs and the ancient "dragonflies" like Meganeura, Argentavis, the unrelated seabird Osteodontornis and the less-known relatives of both deserve really the Giant Flyer title. This bird had a wingspan of about 7 m, as much as Pteranodon but heavier: while this pterosaur weighed about 30 kg, like a child, Argentavis weighed an impressive 80 kg, like an adult human or a small ostrich, or a small Quetzalcoatlus specimen — remember pterosaurs were comparatively lighter than birds because of their totally hollow bones. Argentavis could well be renamed the Feathered Airplane. To understand how majestic this ancient raptor was in life, imagine Argentavis as a giant condor with a ostrich-sized body, huge roc-like wings, a sharp uncinated beak, and a love for carrion (and maybe even an occasional hunting attitude).
Found in 1980 in Argentina at the start of The '80s, Argentavis lived slightly before the famous "American Pliocenic Interchange" of fauna from the two Americas, and was nearly contemporaneous of the giant running bird Phorusrhacos. Both shared the typical eagle-like uncinated beak for tearing meat, but were not close relatives. While the phorusrhacid was basically a sorta giant flightless "secretarybird" (and often portrayed with the latter's plumage, like in Walking With Beasts), Argentavis was more like a giant vulture, but belonged to a distinct family from modern condors: the Teratornithids, and sometimes nicknamed "the giant teratorn" for this.
- Entry Time: undetermined
- Trope Maker: its status as "the biggest flying bird ever"
Sorry, these aren't here. If you're looking for Aurornis, Confuciusornis, Jeholornis, Gargantuavis, Dromornis, Pelagornis, Anthropornis, Presbyornis, Copepteryx, Ornimegalonyx, Amplibuteo, and others, see here.
Sauropods are the mostly gigantic quadrupedal plant-eating dinosaurs with long necks and tails. Some of them were the largest land animals that ever lived, but not quite as massive as they seem: the weight of most of them was brought down significantly by a system of air sacs in hollow bones, similar to theropod, and hence bird, skeletons.
Since sauropods could appear rather similar to each other in size and appearance, only a few of them will usually be identified/identifiable in Fictionland: Brontosaurus/Apatosaurus, Brachiosaurus/Giraffatitan, and Diplodocus. Their iconic status is due to several factors: the early time of their discovery, the relative completeness of their remains, and for having held some "record" in the past the diplodocus has long been the "longest" land animal ever, the brachiosaur the "tallest" and "heaviest", while the brontosaur, being the very first mounted sauropod in a museum, was the first that became popular.
Today scientists recognize more than two hundred sauropod genera, but pop culture ignores most of them. All the three most known sauropods are from Late Jurassic North America (even though the best-known brachiosaur species was found in Africa), but in Real Life sauropods lived worldwide from the Early Jurassic up to the end of the Dinosaur Age. However, in recent years some other sauropods have received attention in media, but only because were said to be "Longer! Taller! Heavier!" than the traditional record-holders. Some really were, but other weren't even real animals. You can find them here classified as "little stock". Camarasaurus, Mamenchisaurus, Saltasaurus, and a few others can also make occasional appearances.
Common inaccuracies in sauropod portraits
If a writer relies on pre-Renaissance science, a featured sauropod is up to its armpits in water and living in swamps while lazily munching some swamp weeds.
Before The '70s, the dominant but incorrect hypothesis said they needed to spend most of their time in water to support their massive bulk and to escape the allegedly non-swimming theropods. Modern science says sauropods were terrestrial, though able to swim in an elephant style if needed. Footprints demonstrate all this: they were mainly made on dry soil and show an elephant-like gait —however, some tracks show only the forefeet. The latter were produced by sauropods crossing a river and only touching the bottom with their forelimbs. Buoyed by internal airsacs, their hindquarters and hindlegs were suspended near the surface while swimming. If the sauropods were really swamp-specialists, they would have had a high chance of slipping in the mud with fatal consequences. If lucky enough to survive the fall, they'd starve to death from lack of nutritious food, because swamp weeds are very poor in nutrients. With their bodies submerged, their ribcages wouldn't even be capable of expanding due to water pressure, suffocating them. The alleged weakness of their teeth and the high placement of their nasal openings are not real proof for an amphibious, swamp weed-eating lifestyle. Since sauropods skulls have high-settled nasal openings, they are classically shown with their nostrils on the tops of their heads like the blowholes of a whale; it was recently hypothesized they might actually have been on the ends of their snouts like every other dinosaur. Finally, footprints show carnivorous dinosaurs were capable of swimming using their hindlegs as shown by the aforementioned alleged Dilophosaurus footprints, making the sauropods' fleeing in water to escape them potentially useless.
Among other mistakes when portraying sauropods, one very common is to show them with elephant-like nails or hooves, falling straight in Most Writers Are Mammals. Actually, sauropods had true claws. They usually had a thumb-claw on each forefoot (which was narrower than in modern elephants) and three claws on each hindfoot (which was broader and more elephant-like than the forefoot). Even so, in most portrayals that do show clawed sauropods, they usually have four or five claws on each foot. More related to Reptiles Are Abhorrent is the tendency of depicting sauropods' necks and tails as serpentine: you'll even find brontosaurs using their necks like snakes when attacking their prey. Actually, their necks had relatively few vertebrae, like a giraffe's, and were relatively stiff, especially if compared with their flexible (but not serpentine) tails, which often had 50-70 or more bones. In the oldest scientific depictions, sauropods were often shown with splayed limbs, not pillar-like, and crawling a bit like a giant tortoise. Recently, a new study suggests that, due to the way their teeth are preserved, sauropods had a keratin covering on their mouths forming into a beak-like structure, instead of fleshy lips or toothy grins as traditionally depicted.
The Sauropod(s?) par Excellence: Apatosaurus & Brontosaurus ***
Both lived in the Late Jurassic, 154 to 150 million years ago, in what is now the USA. They were basically identical in shape: both were large but less than other sauropods, 75 ft/23 m long and weighing at least 23 metric tons - equal to roughly four elephants. The neck made up about a quarter of their total length, the tail about half. Their overall size is often exaggerated in popular writing, for instance by claiming that Brontosaurus weighed as much as 10 elephants, or even that it was the largest dinosaur (one could assume the writer knew only one type of sauropod).
The head was small and slender; the teeth were peg-like and found only at the tips of the jaws. The neck had more than 10 vertebrae, and was of average length but wider than in other sauropods. The body was stocky and deep; the hips were taller than the shoulders. The legs were robust, even more so than in most sauropods, the hindlimbs longer than the forelimbs. The tail was very long with about 80 vertebrae, thin and whiplike near the end.
Apatosaurus is one of the few sauropod genera already known to science when dinosaurs entered pop culture in the 1900s. Marsh described the first species in 1877, in full Bone Wars context, but its first remains were incomplete. Just two years later Marsh described a second alleged Apatosaurus species as a distinct animal, Brontosaurus. The latter became the iconic image of a sauropod for most the 1900s. Brontosaurus and Tyrannosaurus were the ultimate stock dinosaurs in their respective roles as herbivore and carnivore, and contenders for the title of THE overall most iconic dinosaur. In classic dino-stories the brontosaur's (or other sauropods') designated role is the Gentle Giant Sauropod, while T. rex or Allosaurus is the Big Bad, Stegosaurus the Dumb Dino, Triceratops the Temper-Ceratops, the "raptors" the Small Baddies, ornithopods the Friendly Fodder... unless Everything is Trying to Kill You, of course. In the classic version of King Kong, brontosaurs are meat eaters.
Why has Apatosaurus long been considered the only correct name for this pair of dinosaurs? Because scientific rules say if one animal is assigned two scientific names only the first one is valid, and "Apatosaurus" was coined two years before "Brontosaurus". The latter means "thunder lizard" (probably a reference to the booming sounds sauropods might have made when walking), while the former means "deceptive lizard" a much less cool name but, surpisingly, the most apt one.
And then, why has just Brontosaurus been the traditionally most popular sauropod, despite being smaller than Brachiosaurus and shorter than Diplodocus? Probably because the first-ever mounted display of a sauropod skeleton erected at the American Museum of Natural History in 1905 was based on a mostly complete Apatosaurus skeleton, with missing parts borrowed from other sauropod specimens — which also gave the display skeleton a short, boxy head and blunt tail, both incorrect. However, the Museum chose to label the display "Brontosaurus". Other museums followed suit with similar Brontosaurus displays. Popular writing and dino-art kept spreading the at-the-time incorrect name, and the ghost of Brontosaurus still haunts Apatosaurus, as does the image of the short, round head even though the long-narrow-head portrayal is starting to become more known among general public. The actual apatosaurian skull was discovered only in year 1975, and is long and flat like that of its relative Diplodocus, not short and round like in the first Brontosaurus mount.
Peter Jackson's King Kong (2005) referenced all this situation by having a newly-discovered dinosaur on Kong Island be named Brontosaurus in the special features on the DVD. A nice homage, but in reality, once a name is used, even if it's invalidated, it can never be used again for a new animal, lest later researchers be left with no idea which Brontosaurus you're talking about.
Even though the name "Apatosaurus" is today more known among common people than before thanks to documentary media, it could fall again in oblivion if recent proposals are confirmed in the next few years. Since the early 20th century the genus Apatosaurus has traditionally included Apatosaurus ajax (the first described species: Ajax was a greek hero of the Iliad poem renowed for its great height and strength), Apatosaurus excelsus (excelsus = elevated), and Apatosaurus louisae (form Andrew Carnegie's wife Louisa), plus two lesser-known, recently-identified species. However, in 2015, a new study re-classified Apatosaurus excelsus and the two recently-identified species in the genus Brontosaurus after finding differences between them and A. ajax + A. louisae together. If further studies ultimately confirm this proposal, both genus names will be validated, with the more famous species becoming Brontosaurus once again.
Winsor McCay's famous 1914 Gertie the Dinosaur made Brontosaurus the very first dinosaur in cinema, and the very first character deliberately created for a cartoon. Interestingly, she's shown as a land animal, anticipating a largely-discarded theory for more than half a century. Gertie is basically portrayed like a domesticated elephant, and, interestingly, has the correct head shape for a brontosaur: since the brontosaurian head was considered round at the time, some hypothesize she's actually meant to be a Diplodocus.
- Entry Time: 1905
- Trope Maker: Display at American Museum of Natural History (as Brontosaurus)
The "Longest One": Diplodocus **
Living in western North America during the Late Jurassic Period (154-150 million years ago), Diplodocus was a neighbor of Brontosaurus & Apatosaurus. These three dinosaurs belonged to the same family, Diplodocidae, and many features of Brontosaurus & Apatosaurus (the whip-like tail, the skull shape, and the longer hindlimbs) are shared by Diplodocus. Unlike the bronto/apato's ones, Diplodocus' portraits have always had a narrow-ended tail and the long head with a flattened snout typical of diplodocids - the Diplodocus' skull and tail-end have been known since the first discoveries. This means the two animals can be easily distinguished from each other in older media. The aforementioned "Gertie" is NOT a good example, being similar to a brontosaur in bulk but to a diplodocus in head, with unrealistically short stub tail of a brachiosaur, and classic elephantine feet and serpentine neck/tail of outdated portrayals.
In more updated depictions, their overall profiles are the main key to telling Diplodocus from Brontosaurus, at least, in documentary media: in cartoons and pop-images (even the most recent ones) you'll easily find both diplodocuses and apato/brontosauruses portrayed with a very generic, "brontosaur"-like look, making them impossible to tell apart. The diplodocuses were actually longer than the apatosaurs and the brontosaurs, from about 80 ft/24 m to 115 ft/35 m, but weighed only about half as much: 10-16 metric tons. The Diplodocus shape was more slender and elegant than the robust Apatosaurus & Brontosaurus, with a longer, slimmer neck; these differences allowed these animals to live side-by-side and avoid competition by browsing different kind of vegetation, since the diplodocus was able to reach higher tree-food. In a sense, Diplodocus was the giraffe of its world, while Bronto/Apatosaurus was the elephant: an "elephant with the head atop of its trunk", to quote Dale Russell.
Diplodocus has classically been qualified as "the longest dinosaur", but this record is now contended by other diplodocids, like Supersaurus. All diplodocid sauropods had long tails, but Diplodocus took this to an extreme: its tail was 14 m/40 ft long, longer alone than a whole T. rex was from nose to tail!. The apatosaur's tail was "only" 10 m/30 ft long, but curiously, the Diplodocus tail had slightly less vertebrae than Apato/Brontosaurus: about 70 vs 80. This could mean that the tail of the latter was a bit more flexible. It has been speculated that the thin end of the diplodocids' tail could have been used as a whip directly against threats, or indirectly by making whip-cracking sounds. The tail vertebrae of diplodocids also had double beams (hence the name Diplodocus: "double beam") that may have protected the blood vessels inside the tail when the tail pressed against the ground. Diplodocid sauropods may have used their tails as a support together with their hindlimbs, lifting their forequarters to reach higher vegetation.
Found during the Bone Wars like Apatosaurus and Brontosaurus, Diplodocus was introduced to the public courtesy of Andrew Carnegie some decades later. He sponsored an expedition that discovered a new Diplodocus species (which was named Diplodocus carnegii), and had the remains mounted in his museum in Pittsburgh. He then donated replicas of it to museums all over the world; as a result, in some European nations, ex. Britain and France, Diplodocus became the iconic sauropod, rather than "Brontosaurus" as in the USA. In other European countries, like Italy, the brontosaur has been regarded as the prototypical sauropod.
In recent years, the British Speculative Documentary Walking with Dinosaurs has popularized some recent theories about Diplodocus and sauropods in general: the straight, horizontal neck posture and the iguana-like spiky back. The first is due to analysis of the neck vertebrae using computer models. Unlike mammals, sauropods had pairs of ribs even in their necks; the shape of these ribs, together with the relatively low number of cervical vertebrae, prevented their necks from being coiled in a snake-like manner. The second arose from a discovery made in the 1990s of a diplo with imprints of horny spikes near its back. Both theories are now disputed: both the base and the end of the sauropods' necks were more flexible, and the animals may have been able to fold their necks and lift them like most modern long-necked animals. The spikes were dermic boneless structures not related to the skeleton; dinosaurs being closer to birds than to lizards, the structures might have been spread over the animal's back like theropod feathers, instead of in a single line like an iguana's. We don't know if other sauropods had similar fleshy/horny spikes, but spiky iguana-like longnecks have been a common sight in books and art in the 2000s as it seems, dino-artists have had hard work getting rid of the Dinosaurs Are Dragons idea.
- Entry Time: 1905
- Trope Maker: Carnegie Museum skeleton and subsequent replicas
The "Tallest One": Brachiosaurus & Giraffatitan **
Brachiosaurus is the third member of the iconic sauropod Power Trio and lived along Bronto/Apatosaurus and Diplodocus in Late Jurassic North America, 154-153 mya, but also allegedly in Africa in the same period. This detail was mentioned as a concrete proof about the Pangaea hypothesis, as brachiosaurs weren't able to cross oceans to migrate from one landmass to another - the continents were still not completely separated from each other in the Jurassic.
From its first description at the start of the 20th century, Brachiosaurus was often considered unofficially "The biggest land animal ever!" until real or alleged new sauropods were described starting in the 1970s. Of course, works made after The '70s may still qualify the brachiosaur in this way: sadly, among them, even Walking with Dinosaurs, at least the original series. Generally thought to weigh between 30 and 50 tons (more than the stock sauropods above), Brachiosaurus has often also been oversized in popular books, so far as to triple its size up to 130 tons, which would make it heavier than any animal alive today, except for the blue whale.
Brachiosaurs are visually distinct from diplodocids in several ways. First, their necks were noticeably longer than their tails, and their backs sloped backwards instead of forwards like a giraffe. Going into more detail, their tails had a thicker end lacking any thin "whip"; their necks were stronger, had more vertebrae and were held more vertically, again like a giraffe; their teeth bordered most of their jaws and were chisel-like, not peg-like; their nasal openings were unfused, placed more forward, and were much wider than diplodocids' (the brachiosaur subgroup of sauropods, "Macronarians", just means "large nostrils"). In the past some paleontologists suggested sauropods had a tapir-like proboscis observing the shape of their skull! Finally, brachiosaurs are almost the only non-bird dinosaurs with forelimbs longer than hindlimbs (Brachiosaurus means "arm lizard"). Sometimes these difference get glossed over in popular media, which may show brachiosaurs with diplodocid heads, necks, bodies, legs, and/or tails. In these cases, they might be recognizable as brachiosaurs only thanks to a more upright body-shape.
As with other sauropods, brachiosaurs were associated with water in older reconstructions. To accommodate their upright shape they were often shown totally submerged in lakes, not simply wading like diplodocids, with only their head and, sometimes, only their nostrils above the water level, making their neck like a giant snorkel. Needless to say, this is quite unrealistic. In modern portrayals, Brachiosaurus (in traditional sense) has often been described as a "prehistoric giraffe" capable of browsing the highest vegetation that other sauropods were not capable of reaching unless diplodocids were able to stand upright on their hindlegs. Brachiosaurs probably werent capable of that, having their center of gravity much farther forward, and their shorter tails didn't provide support (they would only bring a little bit of extra reach anyway). Moreover, as their greater size could have automatically protected adults even against the biggest predators, they probably didn't need to lift their forebody and use the front-legs to fight an Allosaurus or so, nor didn't they need to use their short tail to hit it to death (Diplodocus and Apatosaurus/Brontosaurus probably did both of these).
However, in fictional and sometimes even documentary media, brachiosaurs show unusual athletic skills: in Jurassic Park, a brachiosaur rears up on its hindlegs to reach a tiny branch. In Disney's Dinosaur, the brachiosaur Baylene is able to remain in a fully erect position for 30 seconds to break the wall of a cave with her forefeet. Also in Jurassic Park, a brachiosaur is shown with an oversized head with fleshy lips, chewing vegetation like a cow. Sauropods didn't chew: their teeth were more suited to cutting plant material in the case of the brachiosaur, or to raking it like a comb like the diplodocids.
Strangely, before the '90s "Brachiosaurus" was an unusual sight in cinema, much rarer than "Brontosaurus" and Diplodocus despite its record size. Maybe because brachiosaurian mounts in museums were totally missing in the USA before The '90s, even though the animal was already portrayed in dino-books at the time. Then, in 1993, Spielberg made a brachiosaur the solemn show-opener of his first film (Crichton's eponymous novel had Apatosaurus in this role). Thanks to this and possibly to its cooler look, the brachiosaur has become one of the most frequent longnecks in popular works since then, and many "young" dino-fans now consider it THE iconic sauropod in pop culture, sometimes even using the word "brachiosaur" generically as if it was a synonym of "sauropod", while pre-JP dino-fans still tend to think of "Brontosaurus" (in the USA) or Diplodocus (in Britain) in these roles — of course this is a very rough distinction, since all three dinosaurs are actually very popular in every country.
Brachiosaurus recently went through some naming troubles, but its situation isn't as severe as the traditional Apatosaurus-Brontosaurus deal the name Brachiosaurus has always been valid, however its best-known species, B. brancai, had to be placed in a different genus, named Giraffatitan. Gregory S. Paul first suggested they were distinct in 1988; this suggestion was followed by George Olshevsky in 1991 and Dougal Dixon in 2006 - otherwise, it was not taken seriously until Michael Taylor proved Paul, Olshevsky and Dixon correct in 2009.
Giraffatitan brancai ("Branca's titanic giraffe") was found in Africa in the Tendaguru site two decades after the U.S. brachiosaur (Brachiosaurus altithorax, "tall-chested arm-lizard"), and is known from complete remains which show a distinctive domed skull. An impressive, 12 m tall Giraffatitan skeleton was mounted in the Berlin museum in the 1930s during the Nazi regime, making this dinosaur the most iconic sauropod in Germany: this was also the biggest mounted dino-skeleton until two decades ago, and the model of the popular image of the brachiosaur lasted for decades around the world. On the other hand, the valid Brachiosaurus was long known only from fragments, and its skull was described only few years ago. This skull, which had a smaller dome than Giraffatitan's, was long classified as another kind of sauropod, Camarasaurus (see below); ironically, it was just this skull that was put in the original "Brontosaurus" skeleton. The old pop-cultural "brontosaur" is thus just a Mix-and-Match Critter made of Apatosaurus and Brachiosaurus.
- Entry Time: 1930s
- Trope Maker: Berlin Natural History Museum (now recognized as Giraffatitan)
The "Heaviest Ones": Argentinosaurus and other "heavy-weight" sauropods *
Argentinosaurus was discovered in Argentina in 1993. It lived in the Early Cretaceous, 95 mya, unlike the more famous sauropods, the diplodocids and brachiosaurids, which lived earlier during the Jurassic. Argentinosaurus belonged to a group of sauropods called titanosaurs, which evolved within the Titanosauriformes (which included Brachiosaurus and Giraffatitan) and replaced the earlier sauropods worldwide in the Cretaceous.
Titanosaurs are based on the genus Titanosaurus, which was first described in 1877 and used as a "wastebin taxon" since then. The classification of titanosaur genera is still in debate and many, including Argentinosaurus, are based on fragmentary remains. We don't know how its head looked exactly, because the argentinosaur's skull is not among these remains. New finds and further cladistic research may still change the descriptions of these animals. Titanosaurs seem to have been more compact than earlier sauropods, with shorter necks and tails, solid bones, and wider frames. At least some titanosaurs had crocodile-like skin armor; in one case (Saltasaurus, see below) this was fully developed as bony plates similar to Ankylosaurus. On the other hand, Argentinosaurus probably didn't develop an armored skin.
Length and weight estimations of Argentinosaurus are necessarily speculative, but the consensus seems to put the length at 100 ft/30.3 m (like Diplodocus) and the weight at about 75 metric tons (about twice a Brachiosaurus). Another South American titanosaur, Antarctosaurus, has left some possible remains almost the same size of the argentinosaur, which were found several decades before 1993. Being very scant and dubious, they have been largely ignored. Other sauropods were previously estimated as even heavier than 75 tons, but these valuations appear positively exaggerated. Such heavy land animals would haven't even able to survive, and the blue whale still remains the official record-holder of all time: only other sea creatures could have overweighed it in the past.
In 2002, Chased By Dinosaurs featured a herd of Argentinosaurus. In a memorable scene, Nigel Marven hurries to place weight sensors in front of the herd as it approaches, walking straight towards the camera and messing with the viewer's perspective: a very effective demonstration of the immense size of these animals. Strangely, unlike its predator Giganotosaurusnote Argentinosaurus has not received much attention in fiction since then. Maybe because, size-related impressiveness apart, the Argentinosaurus here do nothing sensational the adults continue to walk apparently unmoved after the Giganotosaurus bring down one of their young. On the other hand, Argentinosaurus became popular among dino-fans for being described as "the biggest ever dinosaur" in the show and in the dino-books of the last decades. But this is not an isolated case. Several other sauropods have at one point been described the same way since the very first sauropod discoveries. One of the first was Atlantosaurus "Atlas lizard" in the late XIX century (see Prehistoric Life - Dinosaurs). Many others followed since then, with scientists seemingly competing with each other for who coined the most awesome name Argentinosaurus is one of the rare exceptions, meaning simply "lizard from Argentina".
Let's face it paleontologists are people too. While they carefully excavate fossils in some dusty badlands location, or sort through boxes of collected fossils in chilly museum basements, they can't help but secretly hope to be the one who discovers or describes Badassosaurus mynamii. Sometimes they do strike gold. Most of the time, they report an unremarkable animal and get the satisfaction of a job well done but very little glory. Then, there are cases like these...
- Ultrasaurus the "Ultra-lizard" is a story written across The '80s and The '90s about two sets of bones and one name. The U.S. set (a bit of backbone and a shoulder girdle, from Colorado) was in 1979 described by James Jensen as Ultrasaurus, the largest dinosaur ever... to the press, not in a scientific paper. It was depicted as a brachiosaurid 30 m long, 16 m tall and with a weight up to 130 tons, making it even bigger than the former record-holder, Supersaurus — which, by the way, was also described by Jensen a bunch of year before, always in Colorado. The South Korean set (a bit of backbone and an upper forearm) was described a few years later as an Ultrasaurus. This, however, prevented the U.S. animal from being called Ultrasaurus officially, so they had to settle for "Ultrasauros" in 1991. It was still the largest dinosaur, though. Well, at least for a few years, until it was realized that the U.S. set of bones was actually from two different animals, a Supersaurus and a Brachiosaurus: the name "Ultrasauros" was consequently discarded in favor of Supersaurus. Before that the U.S. ultrasaur showed up in some documentaries, and is cited in Calvin and Hobbes as well as in the first JP novel (which mentions the following example, too).
- "Seismosaurus". In the early 1990s Ultrasaurus had to face a rival for "the biggest" title: the "Seismic lizard", popularly nicknamed the "Earth-Shaker". A diplodocid from New Mexico with an estimated length of 177 ft/54 m and an estimated weight of 112 tons, which makes it almost twice as long as a blue whale, and almost two thirds of the blue whale's weight. Impressive? Well, when other experts got a look at it they determined that the size calculation had been thrown off by misplaced vertebrae, that 95-110 ft/29-33 m was a more accurate estimation, and, more recently, that the seismosaur was simply an old, well-grown Diplodocus. The name Seismosaurus is now discarded.
- Supersaurus the "Super-lizard", as said above, was found in Colorado in the 1970s. It was described from a few bones as a brachiosaurid of unusual size, twice as long as Brachiosaurus, and hailed as the first sauropod "bigger than the brachiosaur". When more remains were found, Supersaurus was reclassified as a diplodocid, longer and more massive than those previously known but not excessively so. However, an analysis of the fossils in 2016 suggests that, like Seismosaurus, it also might simply be an overgrown specimen of a better-known dinosaur: Barosaurus, in this case — the hypothesis that Supersaurus and Barosaurus were the same animal was already postulated in the eighties, but was discarded by most experts at the time.
- Sauroposeidon (in reference to Poseidon's lesser-known status as the god of earthquakes, and the animal's great size) was described in 2000 based on four extremely elongated neck vertebrae found in Oklahoma which were, incidentally, first thought to be petrified logs. If it was a brachiosaurid, it might have had the longest neck of every creature ever, even longer than the neck of Mamenchisaurus. Also Supersaurus, the U.S. "Ultrasaurus", and "Seismosaurus" were hyped to have been even longer-necked than Mamenchisaurus, and/or longer-tailed than Diplodocus. However, data published in 2012 puts the "poseidon lizard" closer to the titanosaurs. As such, its size is uncertain—the brachiosaur interpretation gives us an animal up to 115 ft/34 m long and weighing 60-80 metric tons. Living in Early Cretaceous USA along with Deinonychus, some portrayals have depicted deinonychosaurs bringing down adult Sauroposeidon which, for some reasons, live in Late Cretaceous.
- Paralititan ("titan of the swamps") is one of the several newly-found titanosaurians cited as possible contenders of Argentinosaurus for "the biggest" title: others are Puertasaurus, Futalognkosaurus, Dreadnoughtus, Notocolossus, Patagotitan, Alamosaurus etc., see also Prehistoric Life - Sauropods. From the same territories as Spinosaurus, it is known from a bit of backbone, a shoulder girdle, and an upper forearm. By comparing the bones with the skeleton of a more complete titanosaurid such as Saltasaurus, Paralititan appears to have been 85 ft/26 m in length and have weighed 59 metric tons. You know, unless it turns out to be a mistake.
- Bruhathkayosaurus. Found in India in the 1990s, this one is, for now, the Up to Eleven example. Described as a titanosaurian sauropod and believed to have weighed 126 metric tons, it was originally estimated at up to 220 tons, even heavier than the blue whale. However, its formal description is extremely inadequate, and it is speculated that the leg and hip bones found are actually petrified wood. But this is not all: our complex-named giant was initially regarded as a theropod. Imagine a carnivorous dinosaur 50 times heavier than a T. rex... Bruhathkayosaurus must join Maraapunisaurus below as another "one that got away"; it seems that its bones were never properly stored out of the elements and got washed away during rainstorms.
- Maraapunisaurus was believed to be a diplodocid that would have been 190 ft/58 m long, and weighed 120 metric tons, making Diplodocus look like a Labrador retriever in comparison but the only find since 1878 is a single vertebra, which has been lost. For a long time, this vertebra was classified as a different species, called Amphicoelias fragillimus within the poorly-known diplodocid genus Amphicoelias (a very incomplete sauropod found in the Bone Wars, maybe another synonym of Barosaurus like what could be for Supersaurus). The meaning of "Amphicoelias fragillimus" is surprisingly bland for one of the most celebrated "heavy weight" sauropods of the Turn of the Millennium and The New '10s: "extremely fragile hollow vertebra". This discovery of the XIX century was long largely forgotten until its original description made by Edward Cope became more widely-known since the 2000s, mainly in Internet circles. However, a more thorough analysis of the vertebra in 2018, based on surviving drawings, suggests that Amphicoelias fragillimus was not a diplodocid at all, but a member of a different family called the rebbachisaurids. A new name was therefore created for it— Maraapunisaurus, from the Southern Ute word meaning "huge". Rebbachisaurs had very big vertebrae in proportion to their bodies, so if it was a rebbachisaurid, Maraapunisaurus might not have been the largest dinosaur after all, although still very large (over 115 ft/34m long and 70 metric tons).
So, which one is the biggest? Depends on the chosen criteria.
- The Longest: Maraapunisaurus if it was a diplodocid; Diplodocus-Barosaurus-Supersaurus-another diplodocid otherwise.
- The Tallest: Sauroposeidon if it was a brachiosaurid; Brachiosaurus-Giraffatitan-another brachiosaurid otherwise.
- The Heaviest: Bruhathkayosaurus if it really existed; Argentinosaurus-Alamosaurus-Puertasaurus-another titanosaurian otherwise.
Good luck to all of you bone-diggers out there.
- Entry Time: 1970s, 1980s, 1990s, 2000s, and 2010s according to the species: 2003 for Argentinosaurus
- Trope Maker: Sensationalism in media and wishful thinking among paleontologists.
The "Most Common One": Camarasaurus *
Who's the most common sauropod in the USA, Apato/Brontosaurus, Brachiosaurus, or Diplodocus? None of them. It was Camarasaurus. Yes, Camarasaurus, not "Camarosaurus". "Camara" in Latin means cavity, a reference of the classic cavities present in most sauropods' vertebrae, included this one.
This dinosaur was as enormous as the former: 18 meters long, a bit shorter than an apatosaur but with the same bulk, and all them shared their same habitat in which other two popular dinosaurs lived, Stegosaurus and Allosaurus. And yet, when was the last time youve heard Camarasaurus in a film/cartoon/comic? Even the famous Speculative Documentary Walking with Dinosaurs has totally ignored it, preferring its cousins instead. The misfortune of Camarasaurus is probably due to not detaining any size-record among sauropods: it has not been either the longest like Diplodocus, or the tallest/heaviest like Brachiosaurus. Furthermore, its first complete skeleton (found in the early XX century in the Dinosaur National Monument between Utah and Colorado) was from a juvenile, leading some books telling the camarasaur was "one of the smallest sauropods". On the other hand, other dino-book have said this dinosaur was 40 m (130 ft long) long and that was "one of the biggest dinosaurs"!
Discovered during the Bone Wars, Camarasaurus is considered by some a rather unsauropod-like sauropod, because of its relatively large head and its much-shorter neck compared to most other sauropods. It tended to be confused with Brontosaurus in the past, because the classic brontosaur portraits have a round head and a short, blunt tail, just like Real Life camarasaurs. Until few years ago, the head and tail of the skeleton at the base of the popular "brontosaur" image were believed belonging actually to a specimen of the "camara", so in books it's classically said "The brontosaur's traditional pictures have the head of Camarasaurus". We now know this fossil pieces came from a specimen of the north-american Brachiosaurus.
Camarasaurus was more related to Brachiosaurus than to Apatosaurus. Both the brachiosaur and the camarasaur had short, boxy skull with wide nasal openings, a nasal crest, and relatively large teeth which bordered the whole jaws - the Diplodocus and Apatosaurus skull was longer and flatter with peg-like teeth only on the jaw-tips. The four legs of Camarasaurus were about the same length, and its back was perfectly horizontal and perhaps even a bit taller on the shoulders: Apatosaurus and Diplodocus has shorter forelimbs than hindlimbs, and their back had a convex silhouette with the tallest point on the hips. With its short neck, Camarasaurus arguably ate lower tree-vegetation than diplodocids and brachiosaurs; we don't know if it was able to lift on its hindlegs and tail to reach higher foliage, being its barycenter more forward than diplodocids, but more backward than brachiosaurs. Even though its tail lacked a "whip" end, it was comparatively longer than a brachiosaur's, and could have been used to hit predators as defense like what diplodocids probably did.
- Entry Time: 2001
- Trope Maker: When Dinosaurs Roamed America (documentary)
The "Longest-Necked Ones": Mamenchisaurus & Barosaurus *
What is the thing that has really made sauropods the most iconic plant-eating dinosaurs? Their size, useless to say. But there are few doubts that their unbelievably long necks have done their part, too. But wait: if you think Brachiosaurus and Diplodocus have disproportionately vast necks, is only because youve never seen their Chinese cousin: Mamenchisaurus ("Ma-Men-Chi lizard"). The latters neck was so long that, if the animal would be still alive today, we could see it drinking some water from a lake with its forelimbs placed 12 m (35 ft) or even 15 m (45 ft) from the shore! In other words: the neck of Mamenchisaurus alone was longer than a whole T. rex, like the tail of Diplodocus alone. This record has made Mamenchisaurus one of the most famed sauropods as well as one of the most classic Chinese dinosaurs. Its worth noting, however, that the classic record of Whoa the longest-neck! is now disputed now by the fragmentary Sauroposeidon, and perhaps other sauropods whose actual length of their necks is only speculative.
Mamenchisaurus lived in the same age of the other stock sauropods (Late Jurassic), but was discovered in 1954, much later than them. Initially believed a close Diplodocus relative, now is thought a more archaic kind of sauropod which incidentally reached a similar shape, though with a much shorter tail not ending with a "whip" but with a small club (the "club" is a very recent discovery, and almost every mamenchisaur depiction show it clubless). Since the head of Mamenchisaurus has long been unknown, the most classic portraits show it with an inaccurate Diplodocus-like head; actually Mamenchisaurus head was more similar to Camarasaurus or Brachiosaurus. In short, the polar opposite of what has happened to the allegedly boxy Apatosaurus head. Like Camarasaurus, it's controversial if the mamenchisaur could lift on its hindlegs, given the weight of its neck and the shortness of its tail: but if it could so, it could have reached an impressive 20 m (60 ft) of height, beating even the brachiosaurs.
To date, the only significative appearance Mamenchisaurus has made in pop-culture was a simple cameo in The Lost World: Jurassic Park, where it's unidentified and unnamed, but it is very common in dinosaur books and older documentary media because of the size of its neck.
Overshadowed by Awesome seems a common trope among dinosaurs. We see a dinosaur, remain struck by its awesomeness but later, another similar yet even cooler dinosaur takes its place in our mind. Barosaurus could be an example. 8/9 m long, its neck was one of the longest in the whole Animal Kingdom... but is definitively overshadowed by the 12/15 m long neck of Mamenchisaurus (as well as that of the brachiosaurs).
Discovered in the USA at the end of the Bone Wars, Barosaurus was one of the closest relative of Diplodocus, and lived as well in Late Jurassic North America; some possible remains from Africa are also known, but are generally thought to be from a different genus, Tornieria. Barosaurus was virtually identical to Diplodocus except for its shorter tail counterbalanced by the longer neck. Its was one of the longest sauropods, only a bit shorter than Diplodocus. Barosaurus means heavy lizard: though apt for a sauropod, it's not totally appropriate. Having the same slender frame of Diplodocus, the barosaur weighed less than other sauropods. The Barosaurus lower notoriety is probably due to the fact that its remains have been less abundant than the Diplodocus ones. However, Barosaurus has gained more fame when a barosaur skeleton was mounted in the American Museum of Natural History in the 1980s. This skeleton is the dino-star of the museum, being mounted erected on the hindlimbs and the tail; 15 m tall, is shown defending its youngster from an attacking Allosaurus. In the same years, one bizarre suggestion was made about its physiology: with such a long neck, Barosaurus may have had eight hearts to pump blood up to its lofty head. These "hearts" were imagined to be placed through the neck, and pulsating synchronically to enhance the blood circulation. There could actually be a bit of reality in this idea: pulsating blood vessels are not unknown in the modern animal world. The problem is... there isnt any evidence to prove all this true on Barosaurus.
Thanks to a very recent reinterpretation of a neck vertebra previously assigned to Supersaurus, Barosaurus now enters the ring for "biggest sauropod" title. This single vertebra alone is over four feet in length, and seems to have belonged to an animal twice the size of other barosaur specimens. This would mean a creature within the ballpark of fifty metres (164 ft) in length and up to ninety metric tonnes if scaled isometrically, and assuming it was proportioned like the other specimens — its neck alone would have been seventeen metres / 50 ft long: longer than the neck of Mamenchisaurus. But this is still only a guess: we have to find more material of this extraordinary specimen to confirm it, like about the "heavy-weight" sauropods listed above in their own section.
- Entry Time: 1997 (Mamenchisaurus); undetermined for Barosaurus
- Trope Maker: The Lost World: Jurassic Park (Mamenchisaurus); the upright skeleton in the New York Museum (Barosaurus)
The "Armored One": Saltasaurus *
When we think about armored dinosaurs, our mind automatically goes to things such as Stegosaurus, Triceratops, Ankylosaurus. Thus, if you are a layman, you could be astonished if we tell you that there were also armored sauropods. Scientists themselves were surprised when such an animal was really discovered in 1980 in the Argentinian province of Salta: they called it Saltasaurus loricatus, meaning "the armored lizard of Salta". It walked around 80 million years after the more popular "three stock sauropod band", almost managing to see the meteor.
Saltasaurus armor was different-looking than Ankylosaurus armor, and more similar to that of a mammalian glyptodont. It had no spikes, and was made by several small round bony scutes of two different size, covering all the upper parts of its torso like a mosaic (some portraits wrongly show this armor covering also the upper neck and tail). Though apparently much lighter than an ankylosaurs, it would have been enough to defend the sauropod against predators like the contemporary horned Carnotaurus. Its tail was robust, so the saltasaur was probably able to lift itself on its rear-legs despite the weight of its armor. We don't know if Argentinosaurus or other colossal armorless titanosaurs were able to do so.
The scientific importance of Saltasaurus raised up even more after the discovery made at the end of the 1990s of a fossilized breeding-site full of nests and hatchlings, the very first known from a sauropod. These remains were attributed to Saltasaurus, but we are not sure if they pertain to its genus. Saltasaurus is also a member of that subgroup of sauropods called titanosaurs: since its discovery, armor plates of several other titanosaurs have since been found, although more incomplete. Other armored sauropods were found before the description of Saltasaurus, but were so fragmentary they were believed ankylosaurs or even crocodiles, ex. Loricosaurus, "armor lizard". Another allegedly armored sauropod, "Lametasaurus", was described in India from mixed remains of crocs, titanosaurs, and carnotaur relatives!
Saltasaurus was also considerably smaller than all the sauropods above: it was "only" 12 m long and not much heavier than an elephant. Not counting the bony plates, its shape was that of a generic sauropod, with forelegs shorter than hindlegs and middle-length neck and tail. Despite its badass-look given by its armor, thus possibly subverting Gentle Giant Sauropod, Saltasaurus still remains a mainly non-fictional animal unlike Carnotaurus, but could enter the fiction work in the future more widely (see below).
- Entry Time: 2003
- Trope Maker: Dinosaur Planet (documentary)
A Whale of a Dinosaur: Cetiosaurus *
Which were the biggest animals ever, whales or dinosaurs? Hard question, depends on what criterium you want to use. If you count the length some sauropods could have been even longer than any known whale (blue whale included!), but were still shorter than some modern invertebrates such as the giant ribbonworm Lineus longissimus or some jellyfish (better, their tentacles). If you count the mass, whales probably are still bigger than every dinosaur.
Cetiosaurus, the first sauropod ever described, just means whale-lizard, but this is not a mere reference to its size (18 m, a bit shorter than Apatosaurus but with about the same weight); it was literally believed a whale-thing at one point. First found in 1842 in England slightly after Richard Owen coined the word dinosaur, its first remains were so incomplete that Owen couldnt believe such a heavy animal could live on land. Since limb bones were missing, he thought the owner was a non-dinosaurian marine reptile (remember sea-reptiles were already very well-known at the time). When the limb bones were discovered several decades after, the familiar image of an elephantine reptile with long neck and tail came to light. Though not a Wastebin-taxon like Megalosaurus and Iguanodon, Cetiosaurus could be seen as their sauropodian equivalent - incidentally, lived just alongside Megalosaurus in Middle Jurassic Europe, but some possible remains traditionally classified as Cetiosaurus have been found in Africa too, more precisely Morocco.
Cetiosaurus has been the archetypical basal sauropod in popular dinosaur books, and lived before the Stock Trio, 20/30 million years before them. Among the cetiosaur's primitive traits, it had a more generic skull and teeth than a diplodocid or a brachiosaurid, a tail of middle size, and above all compact vertebrae instead of hollow - cavities in the backbone is a typical feature of more evolved sauropods like Apatosaurus, Diplodocus, Brachiosaurus and Camarasaurus (the latters name just meaning lizard with cavities). These sauropods were discovered in North America just in the period of the cetiosaurs correct interpretation. Interesting that Cetiosaurus should have appeared in the WWD episode dedicated to sea-reptiles together with the theropod Eustreptospondylus, living in the same small Late Jurassic islands 150 mya: both cases are Anachronism Stew because both dinos were from Europe but Middle Jurassic, 20 my earlier than the show.
- Entry Time: undetermined
- Trope Maker: its status as "the first-found sauropod"
Sauropods or Stegosaurs?: Shunosaurus & Amargasaurus *
Other two sauropods that possibly can subvert Gentle Giant Sauropod as well if portrayed in fiction, like Saltasaurus. Not every sauropod is either Diplodocoid or Macronarian (Diplodocoid+Macronarian =Neosauropod, "new sauropod"). Many were more primitive than both: Cetiosaurus and Mamenchisaurus are two prominent examples. Another basal sauropod like them is Shunosaurus, lit. "lizard from Shu": Shu is one of the old names of the chinese province of Szechuan, where most chinese Jurassic dinosaurs come from.
Shunosaurus lii lived in Chinese Middle Jurassic, before the much bigger Mamenchisaurus, and was found in the seventies, three decades after the latter. Even smaller than Saltasaurus (10 m long), weighing like a single elephant, it was relatively short-necked and with a round head filled with crammed teeth. It had the typical traits of a primitive sauropod.... except for its tail. It was very specialized, ending with a bony-club on its tailtip like an ankylosaur, surrounded by four short spikes like a stegosaur — in other words, a sauropod with a Thagomizer! Several portraits and museum-mounts however show it spike-less, and sometimes even club-less. With its 20 or more skeletons known, Shunosaurus has also been one of the most common sauropod in fossil record. Its tail-club was different than that of an ankylosaur: it was simpler in structure, formed by one single elliptically-shaped piece of bone at the end of the caudal vertebrae, while the "thagomizer" was made of spikes much shorter than stegosaurians.
Amargasaurus cazaui was more evolved: an Early Cretaceous diplodocoid sauropod of the Dicraeosaurid family, known from a single but well-preserved skeleton found in 1984 in Argentina in La Amarga Formation (La Amarga = "the bitter one" in Spanish) and officially described in 1991. Unusually for most sauropods, both Shunosaurus and Amargasaurus have left skull material. About the same size of the shunosaur, Amargasaurus had a short neck, long whip-like tail, and a Diplodocus-like head like the other dicraeosaurian sauropods. Like its Chinese clubtailed distant relative it was one of the most well-armed sauropods: it had pairs of neural spines which arose from its neck, rather similar in look to the pairs of bony plates and spikes of some stegosaurians like Kentrosaurus. Originally these spines were thought to have substained an unusual "double-sail", but according to recent researches they were more probably covered in keratin making them true spikes for defense. Considering the amargasaur's quite small size for a sauropod (10 m long and weighing less than an elephant), the latter option seems the more likely.
Interesting, an Amargasaurus-like "sail" was added in the Primeval TV series to a totally different dinosaur, the pachycephalosaurian Dracorex. Some of the little-stock sauropods listed in this folder (Camarasaurus, Saltasaurus, Amargasaurus) are spottable in one of the sequels of The Land Before Time film marching together with the more famous sauropods, but being unnamed, they act as Genius Bonus.
- Entry Time: The XXI century
- Trope Maker: Dinosaur Revolution (Shunosaurus); Primeval (Amargasaurus, indirectly)
Sorry, these ones aren't here. If you're looking for Titanosaurus, Alamosaurus, Hypselosaurus, Dicraeosaurus, Rebbachisaurus, Vulcanodon, Barapasaurus, Pelorosaurus, Euhelopus, Patagosaurus, Omeisaurus, and others, see here.
Prosauropod means "before the sauropods". Living in the Triassic or Early Jurassic periods, prosauropods were among the very first dinosaurs to appear, and the first dinosaurs to reach elephant size. Some of them may have been the ancestors of the sauropods. The name Prosauropoda isn't formally used nowadays: members of the group are now referred to as basal sauropodomorphs. Plateosaurus, considered the prototypical "sauropod predecessor", has been one of the most common in the fossil record and one of the largest as well. The much smaller Anchisaurus was the first discovered, in 1818; the similar-looking Thecodontosaurus was one of the first known basal sauropodomorphs as well; the middle-sized Massospondylus has recently revealed excellent remains including nests and hatchlings; while Mussaurus is only known from nest and hatchlings. Riojasaurus and Melanorosaurus are noted to be even bigger than Plateosaurus, the medium-sized Lufengosaurus for having been the first dinosaur ever portrayed in a postage-stamp.
The "First Giant": Plateosaurus **
Lived 216-199 million years ago, in the Triassic Period. Plateosaurus is one of the scientifically better-known dinosaurs, and also the most abundant dinosaur in European fossil record. More than 100 specimens are known, and even a "graveyard" in Southern Germany (Trossingen). Plateosaurus was also one of the first dinosaurs described, even before the word "dinosaur" was invented, but Owen didnt include Plateosaurus in his new group (its first remains were very fragmentary). When the genus was being classified into Dinosauria, it was first placed in the theropod branch and thought carnivorous; later, was moved to the prosauropod group. A little-known curiosity is that an older synonym genus of Plateosaurus is just "Dinosaurus".
Its adult size was astonishingly variable, from 16 ft/4.8 m up to 33 ft/10 m, and its weight ranged from 600 kg to 4 metric tons. At a first glance, Plateosaurus looks like a cross between a diplodocid and a theropod. The general body shape was sauropod-like, with a small head, long neck, sturdy body, and long flexible tail (and also the typical thumb-claws). The limbs and stance were theropod-like; it was bipedal, walking on hind legs that were slightly folded, rather than pillar-like. The hindfeet had distinct digits with a claw on each. The neck was shorter and more flexible than a typical sauropod neck thanks to its shorter vertebrae, recalling the necks of some theropods a bit. The head was rather theropod-shaped too, but their teeth were small and blunt, apt to grabbing vegetation (without chewing) instead of tearing meat. The closer relationship with sauropods is betrayed by one detail: the hands and feet of the prosauropods had five digits each like sauropods, while true theropods lost the fifth digit both in their hands and their feet (except for the most primitive controversial theropods, like Herrerasaurus and its relatives, which had five digits on their hands/feet). We still don't know if sauropod-predecessors like Plateosaurus had filamentous skin-structures like theropods or dermic spikes like Diplodocus other than the scales, because skin-impressions in rock of these dinosaurs have not been found yet — a strange thing, considering the prosauropods' notable abundance in fossil record as a whole. Compensating this eggs and nests of "prosauropods" are known, ex. those of Massospondylus and Mussaurus, and known early dino-footprints have been made by these animals elsewhere.
Science Marches On has been a strong factor within Plateosaurus portrayals. When believed a theropod it was depicted with a tripod stance like all large bipedal dinosaurs; one example could be in Fantasia. After being classified as a sauropod relative, the plateosaur has usually appeared as a slow quadruped but able to rear up its hindlegs like diplodocids, either to reach higher foliage or for defensive purpose (like in Walking with Dinosaurs). The exclusively bipedal portrait re-emerged only very recently, and today scientists believe Plateosaurus kept its body horizontally like theropods, and like them, was capable of relatively rapid runs if necessary. It may have defended itself with its thumbclaws, like what's believed about another not-related dinosaur, Iguanodon. The "plateo"'s large size could have evolved to avoid predation by the carnivorous dinosaurs, which were still small and gracile at the time; the only predators that were possibly able to defeat the adults were basal archosaurs such as the contemporaneous Teratosaurus.
The two most-known Triassic dinosaurs, Plateosaurus and Coelophysis, are among the most abundant in fossil record but among the least common in pop culture. Plateosaurus appearances in fiction are very rare; in documentaries, it is usually shown only to emphasize the dinosaurs' "rise to power", a subtrope probably just arosen from Walking with Dinosaurs. Even though some Plateosaurus-looking dinosaurs occasionally crop up in TV (such as Dino), they are more likely "humanized" sauropods or Mix-and-Match Critter things.
First North American Dinosaur Discovery: Anchisaurus *
Despite its scarce fossil record, Anchisaurus is one of the most famed sauropod predecessors, thanks to its historical importance. It was the very first dinosaur ever discovered in North America (1818, six years before Megalosaurus), but was not recognized as a dinosaur at the time; this happened only during the Bone Wars sixty years later, thanks to Othniel Charles Marsh.
An Early Jurassic animal, thus more recent than the prototypical Plateosaurus, Anchisaurus was much smaller: only 9 ft long, about one third of an average plateosaur, and 50 times less-heavy. It was one of the most unsauropod-like "prosauropods, with its rather short neck and limbs: its old quadrupedal portraits made it looking like a long-necked lizard (Anchisaurus means "almost-lizard"). Like all sauropodomorphs it had large curved thumbclaws for defense: unlike sauropods, however, Anchisaurus and the other prosauropods could have used them also as tools for grasping or cutting foliage, or for digging the soil in search of roots or insects.
Talking about its modern classification: several scientists now think Anchisaurus, despite its primitive look, was a near sauropod, and some in the 2000s have even cited it as "the earliest sauropod". The larger-sized Ammosaurus was believed a relative of Anchisaurus from the same habitat, but it is today generally regarded as a species of Anchisaurus. Some alleged Anchisaurus remains were once signaled from Southern Africa from the same epoch of Massospondylus below, but they actually pertain to other kinds of prosauropods.
Anchisaurus appears in one popular documentary of the early 2000s as the chosen prey for Dilophosaurus, who hurts it with exagerrately-powerful forelimbs and hand-claws before killing it with its jaws: the anchisaur here is oversized, and actually more similar in proportions to Massospondylus. Some in the past have hyped that Anchisaurus was the real inspirer of the popular pet-dinosaur of The Flintstones, Dino, because of its short legs.
- Entry Time: 2003
- Trope Maker: When Dinosaurs Roamed America
From Obscure to Well-Known: Massospondylus *
According to some, Massospondylus ("massive vertebra") is a quite musically-named dinosaur: its full scientific name is Massospondylus carinatus, "keeled massive vertebra". Described in the XIX century from fragmentary african remains, this is today the most scientifically well-known "prosauropod", even more than Plateosaurus itself: almost a hundred individuals of the massospondyl have been discovered so far in Southern Africa, and some doubtful remains from North America are also known. To date, this is the most abundant dinosaur in African fossil record, just like the plateosaur is in Europe.
Massospondylus was a core prosauropod (like Plateosaurus) according to modern classifications. 4-5 m long and perhaps weighing 300 kg, Massospondylus was middle-sized between Plateosaurus and Anchisaurus. Compared with the plateosaur it had a smaller head, slimmer neck, nimbler limbs and shorter trunk, in short, was a bit like a Plateosaurus which has undergone a weight-reducing diet (or alternatively a long-legged, long-necked Anchisaurus). Like the latter, in spite of being apparently more primitive and less sauropod-like than Plateosaurus, Massospondylus lived after it, in the Early Jurassic, and was actually one of the last "prosauropods". Because of its slight overbite, one scientist once hypothized that Massospondylus had a beak on the tip of its lower jaw (an unusual trait for a sauropodomorph, more typical for basal ornithischians), but this has demonstrated being not true.
Massospondylus started to be more common in fossil record since The '70s, thanks to more than 90 skeletons found in Southern Africa; more recently, in the 2000s, many nests and hatchlings have been discovered in South Africa from this dinosaur, making Massospondylus one of the dinosaurs we ultimately know the most about. The lacking of teeth among the youngest nestlings has surprised scientists: this makes another concrete proof among dinosaurs about active parental care from their parents, since these youngsters couldn't feed on their own with their toothless jaws. This discover closely recalls that of the duck-billed Maiasaura in the 1980s, but with an important difference: the latter's children were all toothy. With their blunt but serrated teeth bordering the whole jaws (typical of prosauropods), adult Massospondylus were probably vegetarian, even though they could have also caught some insects occasionally: some gastroliths (gizzard-stones) found in the ribcage of some individuals seem to confirm a mainly herbivorous diet. All these discoveries started since the 1970s have made Massospondylus a common sight in non-fictional media, earning to it the status of "little-stock" dinosaur.
- Entry Time: 1990s
- Trope Maker: The deep knowledge of its biology
Other sauropod predecessors
Sorry, these ones aren't here. If you're looking for Thecodontosaurus, Lufengosaurus, Mussaurus, Riojasaurus, Melanorosaurus, Efraasia, Yunnanosaurus, Euskelosaurus, Glacialisaurus, and others, see here.