Useful Notes: Prehistoric Life
This page talks about prehistoric life
by making several examples of extinct creatures, from plants to non-human hominids. Of course
dinosaurs receive more details than the other groups, but it would be a really, really
incomplete list without non-dinos.
This page only talks about non-stock animals: that is, creatures that may appear in popular-science works but have never been portrayed in film/comics/novels, or at least have been portrayed only occasionally. The vast majority of dinosaurs
are in this category; and yet, they are as cool as their famous relatives. If you want to see thing about the most popular dinos and non-dinos, there is already some information here
To help you:
The geologic and biologic history of the Earth is divided into four eons
: Hadean, Archean, Proterozoic, and Phanerozoic. Each eon is divided into eras, which are themselves subdivided into periods, which are in turn sub-sub-divided into epochs. Since we know a heck of a lot more about the recent past than we do about the very very ancient past, the first three eons are sometimes grouped together into a single "supereon" known simply as the Pre-Cambrian.
: Earth before 542 million years ago.
- Hadean eon: Starting from the formation of the Earth 4.6 billion years ago, and lasting until the Earth cooled, solidified, and generally calmed down enough that fossilized bacteria could form. The Hadean eon as it was first conceived began with Earth congealing from space dust and ended with the first rocks surviving to this day formed; before that, Earth's crust was too unstable to leave geological evidence. Later, some miraculously surviving rock samples from the Hadean were found in Greenland.
- Archean eon (formerly Archaeozoic): Starting 3.8 billion years ago, and lasting until oxygen started to build up in the Earth's atmosphere 2.5 billion years ago. This atmospheric oxygen was created by cyanobacteria, and spelled instant death for any life that couldn't evolve aerotolerance. It was the worst case of air pollution in the Earth's history.
- Proterozoic eon: Starting 2.5 billion years ago, and ending a scant 542 million years ago with the Cambrian Explosion. This eon saw the emergence of the first eukaryotic life forms (cells with a nucleus) 1.6-2.1 billion years ago, the first sexually-reproducing organisms 1-1.2 billion years ago, and the first multicellular organisms. The final era of this eon was:
- Neoproterozoic era: Starting 1 billion years ago. At the onset of this era, a supercontinent named Rodinia straddled the Earth's equator. Ice ages came and went which were so severe that the ice sheets reached all the way to the equator, resulting in a Snowball Earth. Rodinia eventually broke up, only to re-form as another supercontinent named Pannotia. The final period of this era was:
- Ediacaran period (formerly Vendian): Starting 635 million years ago, which marked the "Dawn of Animal Life." Or so we think. In any case, multicellular life that probably (but not certainly) belongs to the kingdom Animalia first appears around 580 million years ago; possible fossils are found even earlier, near the beginning of the period, but nothing conclusive. Many possible ancestors of known invertebrate groups show up in the record, including comb-jellies, sponges, corals, anemones, and molluscs, and one fossil might even be a chordate (vertebrate ancestor). Fungi also emerge during this period.
: Earth from 542 million years ago to 251 million years ago.
- Cambrian period: The "Explosion of Life". Most of the main invertebrate groups appeared then, as well as the first vertebrate ancestors. Life was still water-exclusive. Probably. Graptolites, cephalopods, and chitons emerge during this period.
- Ordovician period: First true fish appeared. Arthropods venture onto land. Ended with a mass extinction.
- Silurian period: First jawed fish and later ray-finned fish appeared. Plants and scorpions started to colonize dryland.
- Devonian period: The Fish Golden Age. The first four-limbed vertebrates appeared. Insects, crabs, ferns, and sharks evolve. Ended with a mass extinction.
- Carboniferous period: Forests spread around the world. The Golden Age of Insects and Amphibians. Sharks reach large sizes, and ratfish, amniotes, synapsids, diapsids, and hagfish evolve.
In the United States, rocks from the Carboniferous Period are so plentiful that they've allowed geologists there to divide the period into two:
- Mississippian period: This period, which is called the Lower Carboniferous elsewhere in the world, saw a major rebound in diversity from the mass extinction that ended the Devonian. This paved the way for the life forms of the next period, the:
- Pennsylvanian period: This period, which is called the Upper Carboniferous elsewhere in the world, contains the massive coal deposits (actually the remains of vast swampy forests) that give the Carboniferous its name.note
- Permian period: The supercontinent of Pangea is formed, and Earth becomes more arid. The Golden Age of the Mammal-Ancestors. Beetles and therapsids evolve. Temnospondyls and pelycosaurs diversify. Ended with the worst mass extinction ever.
: Earth from 251 million years ago to 65 million years ago.
- Triassic period: Seed plants diversified. True reptiles replaced mammal-ancestors. Most of the main groups of land-vertebrates still alive today appeared, dinosaurs and mammals are among them. Many groups that did not leave modern descendants, such as pterosaurs and many marine reptile groups, evolved as well. Ended with a mass extinction.
- Jurassic period: Dinosaurs became the largest and most diversified land-animals, and some became fliers (including possible protobirds). New types of pterosaurs and marine reptiles evolved. The three still-living mammalian groups appeared.
- Cretaceous period: Dinosaurs further diversified, and the first dinosaurs universally recognized as birds appeared. Flowering plants and several groups of insects co-evolved, creating the most common land-ecosystem still present today. Modern groups of fish evolved. Despite the movie's name, most of the dinosaurs shown in Jurassic Park flourished in the Cretaceous period, not the Jurassic period note . Ended with the last mass extinction up to the present, known as the K-T Boundary Event*.
: Earth from 65 million years ago to the present day.
- Paleogene period: consists of Paleocene, Eocene and Oligocene epochs. Mammals underwent an explosive evolution, and most still-living lineages appeared, primates included. Birds, crocodilians, turtles, squamates and lissamphibians were among the other land-vertebrates which survived the mass-extinction. At the end, the Earth started to become colder, and polar ices started to form.
- Neogene period: consists of Miocene and Pliocene epochs. Continents acquired their modern placement, and new mountain ranges appeared. Grasslands became a widespread environment, partially replacing forests. New mammalian kinds appeared, among them the first hominids.
- Quaternary period: consists of Pleistocene and Holocene epochs. Started 2.59 million years ago. Several Ice Ages alternated with Interglacials. All modern kinds of plants and animals were already present, but also many now-extinct species. True humans evolved and started to develop our modern traits. The age in which we are living today (specifically the Holocene Epoch) is included in this time period. The only surviving human species, Homo sapiens sapiens, has become a prime environmental factor worldwide.
The first written records started to appear some 5000 years ago. That moment marked the beginning of recorded history. Anything more recent than that ain't prehistoric.
When reading the examples of creatures we made, you'll note that many prehistoric critters can confidentially be put in their group simply observing their hallmark-suffix. Let's list the most common cases. But also note not all
members of each group have their designated suffix; nor these suffixes are necessarily exclusive of these groups (think about the whale Basilosaurus
). Usually these suffixes are latinized Greek; of note is that there are examples from languages aside from Latin and Greek, such as Yutyrannus
("Yu" is Mandarin for "feathered dragon"), Azhdarcho
(named after a Uzbek myth), and Tawa
(named for the Hopi sun god). Even English sometimes: Drinker
(named after 1800 paleontologist Edward Drinker Cope). Other names are related with modern geography: Edmontonia
cames from Edmonton in Canada; Minmi
come from Minmi Crossing and Muttaburra, the places in Australia where their fossils were dug out.
- -saurus: Greek for "lizard": in paleontology identifies reptiles in general (in the traditional sense of the word), not only dinos. Ex: Allosaurus, Plesiosaurus, Scutosaurus, Edaphosaurus. Often identifies amphibians as well: ex. Mastodonsaurus. The whale Basilosaurus is an exception due to Science Marches On (it was initially believed a sea-reptile). Also known is the feminine variant -saura: Ex: Maiasaura, Leaellynasaura
- -ceratops: Greek for "horned face": identifies horned dinosaurs. Ex. Pentaceratops, Protoceratops. Most famous dinosaur with this ending is, of course, Triceratops.
- -mimus: Greek for "mimic": mostly identifies small bird-like theropods, expecially ornithomimids (usually preceed by a bird-related prefix). Ex. Garudimimus, Avimimus. Also applies to some larger and smaller dinosaurs, in specific theropods seem to get this name a bit, due to their close relation to avian dinosaurs. Ex. Suchomimus, Sciurumimus.
- -raptor: Greek for "thief", "robber": since the Jurassic Park success identifies mainly dromaeosaurids (ex. Pyroraptor, Bambiraptor), but many other theropod dinosaurs have this as well. Ex. Oviraptor, Megaraptor, and Fukuiraptor. Accipitrids and Falconids are commonly called raptors, but there is yet to be a genus in this group that has this ending to it's specific name. Related suffixes for theropods are -venator ("hunter" in Latin) and -tyrannus ("tyrant"). Ex. Neovenator, Eotyrannus.
- -titan: often attributed to giant sauropods. Ex. Giraffatitan and Paralititan. But also some hadrosaurs: Olorotitan, "Anatotitan".
- -pelta: (meaning "armor"): very common in ankylosaurian names. Ex. Sauropelta. Many ankylosaurians have their name ending in -a: ex. Tarchia, Gastonia.
- -cephale/cephalus (greek for "head"): "cephale" is typical of pachycephalosaurians, Ex. Homalocephale. -cephalus examples include Euoplocephalus.
- -dactylus: Greek for "digit": typically identifies pterosaurs, from the namesake [Ptero-]Dactylus ("winged digit"). Ex: Cearadactylus, Preondactylus.
- -suchus: Greek for "crocodile": in paleontology identifies crocodilians, crocodile-looking reptiles or crocodile-looking amphibians. Ex: Deinosuchus, Titanosuchus and Koolasuchus.
- -therium: Greek for "beast", "wild animal"; most prehistoric mammals have this —- the famous documentary Walking With Beasts was just named so in reference to the countless -theriums here Ex. Uintatherium, Indricotherium, Brontotherium, Chalicotherium, Arsinoitherium, Deinotherium, Sivatherium, Moeritherium. But perhaps the most famous example is Megatherium ("big beast"). Several -saurus have their -therium counterpart, too: "Brontosaurus" - "Brontotherium"; Stegosaurus - Stegotherium; Ankylosaurus - Ancylotherium; Megalosaurus - Megatherium; Ceratosaurus - Ceratotherium (which is also the scientific name of the modern White Rhino!)
- -felis: Greek for "cat", this is applied to extinct felids quite a bit of the time. Example: Dinofelis. -smilus (meaning "knife") can indicate sabre-tooths or pseudo-sabretooths. Ex. Eusmilus, Thylacosmilus.
- -cyon, cyno-: Greek for "dog", this is applied to extinct canids but also other canid-looking mammals. Ex. Hesperocyon, Cynodesmus.
- -pithecus: Greek for "monkey": the hallmark of most prehistoric primates, human ancestors included. Ex. Oreopithecus and Australopithecus.
- -ornis and -avis: Greek and Latin (respectively) for "bird": identifies... guess. Ex: Osteodontornis, Icthyornis and Argentavis.
- -chelon, chelys: Greek for "turtle", "tortoise": identifies... guess. Ex. Archelon, Colossochelys.
- -batrachus: Greek for "frog": several ancient amphibians (not only frogs) have this. Ex. Triadobatrachus.
- -ichthys: Greek for "fish": indicates many fish aka non-tetrapod vertebrates. Ex. Leedsichthys, Saurichthys. While Ichthyosaurus means "fish-lizard".
- -aspis: Greek for "shield": almost all names of Ostracoderms and of some Placoderms (both armored fish) have this suffix. Ex. Pteraspis, Cephalaspis, Drepanaspis.
- -ceras: Greek for "horn": most Ammonites and Nautiloids (cephalopod molluscs) have this, due to their horn-shaped shells. Ex. Orthoceras and Cameroceras.
- -pteris: Greek for "fern": many extinct fern-looking plants end with this. Ex. Archaeopteris, Glossopteris.
Then, there also suffixes not-indicating a specific groups of animals, marking anatomical traits instead:
- -odon/odonto: Greek for "tooth", animals with notable teeth (or known mainly by their teeth) can get names ending with this or simply having it in their name upon description. Ex. Heterodontosaurus and Carcharodontosaurus ("different-toothed lizard" and "shark-toothed lizard", respectively.) Mammalian example is Smilodon (carving knife tooth). Other examples: Iguanodon, Hypsilophodon, Troodon, Dimetrodon, Dimorphodon, and Glyptodon. A deceptive case is Pteranodon, which actually means "winged with no teeth.
- -ceras/cerato/ceros/ceroto: Greek for "horn". Guess what is the prominent feature these creatures bear. Ex. Megaloceros, Teleoceras, Ceratosaurus. Also the common name of a famous modern animal: the Rhinoceros of course (meaning "horned nose").
- -lophus/lopho: Greek for "crest", indicates animals with some sort of crest. Ex. the dinosaurs Parasaurolophus and Dilophosaurus.
- -gnathus/gnatho: Greek for "jaw". Ex. Compsognathus, Cynognathus, Gnathosaurus.
- -pteryx/-ptero/-pterus/-pteron: Greek for wing, feather, but also fin. Examples: the winged Archaeopteryx, Pterodaustro, and Dsungaripterus, and the fish Eusthenopteron.
- -onyx/-onychus: Greek for "nail", "claw". theropods with one enlarged claw in their hand/foot have often these suffixes. Ex. Baryonyx, Deinonychus. Alvarezsaurids names end with the variant -onykus. Ex. Mononykus.
- -spondylus: Greek for "vertebra". Ex. Massospondylus, Eustreptospondylus.
- -acanthus/acantho: Greek for "spike", "spine": many spiky/spiny critters include this in their name. Ex. Polacanthus, Stethacanthus, Metriacanthosaurus.
- -ch(e)irus/-ch(e)iro: Greek for "hand". Ex. Deinocheirus, Chirostenotes.
- -pus/-po: Greek for "foot": Ex. Moropus, Astrapotherium.
- -urus/uro: Greek for "tail". Ex. Dacentrurus, Coelurus, Urocordylus.
Common prefixes or suffixes with the function of adjectives:
- mono/di/tri/tetra/penta/hexa: Greek for "one/two/three/four/five/six": Ex. Monolophosaurus, Dilophosaurus, Triceratops, Tetraceratops, Pentaceratops, Hexameryx.
- a/an: the "privative A". Put in front of a word, indicates the thing in question is missing in the animal. For example, Aceratherium means "beast without horns". If the word begins with a vowel, the "A" becomes "AN". Ex. Anoplotherium "beast lacking armor". And then, Pter-AN-odon (see above).
- eo-: Greek for "dawn": indicates primitive animals within a group: Ex. Eoraptor, Eoceratops.
- eu-: Greek for "good", "well": Ex. Eusthenopteron means "well-narrow fin", Eurhinosaurus "well-nosed lizard".
- pro-: Greek for "before": Ex. Procompsognathus means "before Compsognathus".
- proto-: Greek for "the first": Ex. Protoceratops is "the first horned face".
- para-: Greek for "near", "beside": Ex. Parasaurolophus meaning "near Saurolophus".
- coel-: Greek for "hollow": Ex. Coelophysis, Coeluroides, Opisthocoelicaudia.
- sino-: Greek for "Chinese": Ex. Sinornithosaurus, Sinosaurus, Sinraptor.
- syn-: Greek for "fused", "united": Ex. Syntarsus, Synthetoceras.
- -oides: Greek for "similar to", "false": Ex. Saurornithoides, Merycoidodon.
- -ops: Greek for "eye", "face", "appearence": Ex. Moschops, Megacerops, Dolichorhynchops. -ceratops is a composed suffix made of cerato ("horn") and ops.
And oh, don't forget these:
- dino-/deino-: Greek for "terrible" (but also "ponderous", "magnificent"). Ex. Deinosuchus, Dinofelis, Dinichthys, and of course, Dinosaur. Related with it are gorgo- (ex. Gorgosaurus, Gorgonops) and terato- (Teratosaurus, Teratornis), both meaning "monstrous" in Greek.
- -long: Simplified Chinese for dragon. The most recent stock suffix. Dinosaurs found in China since the 2000s have usually been named with this ending. Examples include Guanlong, Bolong, Dilong and Tianyulong