History UsefulNotes / PrehistoricLifeHadrosaurPredecessors

* The heavily-built ''Lurdusaurus'' (informally named "Gravisaurus" before its official description: both names mean "heavy lizard") seems very closely-related to ''Iguanodon'', even though shared its habitat with ''Ouranosaurus'' in North Africa. Interestingly, ''Lurdusaurus'' seems showing adaptations for a semi-aquatic lifestyle, which is unusual for ornithischian dinosaurs. It had indeed the shape rather like a hippopotamus, with huge body substained by short strong legs. It was as big as ''Iguanodon'' but less tall, thanks to its shorter legs. It is also worthy of note because of its gigantic thumbspikes. Interesting that the aquatic hyp was also made for another ornithischian, the basal ceratopsian ''[[UsefulNotes/PrehistoricLifeCeratopsidPredecessors Koreaceratops]]'' from [[ExactlyWhatItSaysOnTheTin Korea]]: found only in 2012, its describer believed it was actually a ''marine'' dinosaur. Today, thanks to the most recent findings, the saurischian ''[[UsefulNotes/StockDinosaursSaurischianDinosaurs Spinosaurus]]'' is known to have been a ''really'' sea-dwelling dinosaur.

* On the other hand, the 3/4 m long ''Callovosaurus'' found in England comes from a far more ancient period: the Callovian stage of the Middle Jurassic (hence the name).It was one of the most ancient iguanodontians known: once considered a camptosaurid, it's actually more closely related to ''Dryosaurus''. ''[[http://en.wikipedia.org/wiki/Valdosaurus Valdosaurus]]'' ("Weald lizard") was another dryosaurid, also English but Early Cretaceous (like ''Hypsilophodon''); some alleged "Valdosaurus" remains were found in Africa, too. ''[[http://en.wikipedia.org/wiki/Kangnasaurus Kangnasaurus]]'' was bigger, and lived in Early Cretaceous South Africa: known from scanty remains, it owes its name from a local Ranch. ''Phyllodon'', ''Alocodon'', ''Taveirosaurus'', and ''Trimucrodon'' from Portugal are known only from teeth, and are thus hard to classify.

* About South American discoveries, apart from the enigmatic ''Loncosaurus'' (found as well in the early XX century but described from a single femur mixed with a theropod tooth), there are few non-hadrosaur ornithopods found in the 1990s or later, the largest one being the 6 m long ''[[http://en.wikipedia.org/wiki/Macrogryphosaurus Macrogryphosaurus]]''. Another is meaningfully named ''Notohypsilophodon'', the "Southern Hypsilophodon". Curiously, one small South American ornithopod described in 1996 [[FollowTheLeader has got]] a feminine name reminescent of ''Leaellynasaura'': ''Gasparinisaura'' ("Gasparini's lizard"). Since that other small ornithischians around the world have received the suffix "-saura", for example "Bugenasaura" (now regarded as a synonym of ''Thescelosaurus'') and, last example, ''[[http://en.wikipedia.org/wiki/Trinisaura Trinisaura]]'', found in Antarctica in the earliest part of 2013 (this one has immediately received a name). Well, [[TheUnfairSex Unfair Sex]] -related names do fit better for [[AnimalMotifs these graceful “gazelle dinos”]] rather than the badass-looking ([[AnimalMotifs and very masculine]]) ankylosaurs.

''Hypsilophodon'' (no bigger than an adult human) is classically countered against ''Iguanodon'', which is the traditional prototype of the the “[[http://en.wikipedia.org/wiki/Iguanodontia iguanodonts]]” (large/heavy non-hadrosaurian ornithopods). [[ScienceMarchesOn Now scientists have found]] “[[http://en.wikipedia.org/wiki/Hypsilophodont hypsilophodonts]]” is an artificial assemblage, while “iguanodonts” now indicates a natural group including not only the most ''Iguanodon''-like animals but also [[UsefulNotes/PrehistoricLifeHadrosaurs duckbills]], pre-duckbills and also some traditional “hypsilophodontians” like ''Dryosaurus''.

* The heavily-built ''Lurdusaurus'' (informally named "Gravisaurus" before its official description: both names mean "heavy lizard") seems very closely-related to ''Iguanodon'', even though shared its habitat with ''Ouranosaurus'' in North Africa. Interestingly, ''Lurdusaurus'' seems showing adaptations for a semi-aquatic lifestyle, which is unusual for ornithischian dinosaurs. It is also worthy of note because of its gigantic thumbspikes. The aquatic hyp was also made for another ornithischian, the basal ceratopsian ''[[UsefulNotes/PrehistoricLifeCeratopsidPredecessors Koreaceratops]]'' from [[ExactlyWhatItSaysOnTheTin Korea]]: found only in 2012, its describer believed it was actually a ''marine'' dinosaur. Today, thanks to the most recent findings, the saurischian ''[[UsefulNotes/StockDinosaursSaurischianDinosaurs Spinosaurus]]'' is known to have been a ''really'' sea-dwelling dinosaur.

* ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Ouranosaurus]]'' is the most well-known among those middle-ways between ''Iguanodon'' and hadrosaurs called “basal hadrosauroids”, and was actually closer to duckbills than to ''Iguanodon'' despite sharing thumbspikes with the latter (though less-developed than the Iguanodon's ones). Unlike true hadrosaurs whose teeth were in number of ''hundreds'' and crammed in "batteries", ''Ouranosaurus'' and the other pre-hadrosaurs had less-numerous teeth placed in one single line on each half-jaw -- the primitive condition of almost all the non-hadrosaur dinosaurs. Among the other possible basal hadrosauroids, other than ''Altirhinus'' and ''[[UsefulNotes/PrehistoricLifeHadrosaurs Probactrosaurus]]'', are also worth of mention ''Protohadros'' and ''[[http://en.wikipedia.org/wiki/Eolambia Eolambia]]'', both discovered in 1998 in the USA. The former was initially considered the earliest hadrosaur (its name just means “the first hadrosaur”); the latter received a similar treatment, initially described as the first ancestor of crested hadrosaurs (''Eolambia'' means "dawn lambeosaurine").

* On the other hand, the heavily-built ''Lurdusaurus'' (informally named "Gravisaurus" before its official description: both names mean "heavy lizard") seems very closely-related to ''Iguanodon'', even though shared its habitat with ''Ouranosaurus'' in North Africa. Interestingly, ''Lurdusaurus'' seems showing adaptations for a semi-aquatic lifestyle, which is unusual for ornithischian dinosaurs. This hyp was also made for another ornithischian, the basal ceratopsian ''[[UsefulNotes/PrehistoricLifeCeratopsidPredecessors Koreaceratops]]'' from [[ExactlyWhatItSaysOnTheTin Korea]]: found only in 2012, its describer believed it was actually a ''marine'' dinosaur. Today, thanks to the most recent findings, the saurischian ''[[UsefulNotes/StockDinosaursSaurischianDinosaurs Spinosaurus]]'' is known to have been a ''really'' sea-dwelling dinosaur.

* Partially compensating, several small bipedal ornithischians have been then discovered in other southern continents, the best-known being ''Leaellynasaura amicagraphica''. It was found in 1989 in Australia along with the single lower jaw of the larger ''[[http://en.wikipedia.org/wiki/Atlascopcosaurus Atlascopcosaurus]]'', so-called from the Atlas-Copco Corporation that funded its excavation. Another Australian "hypsilophodont" described in 1999 is ''Qantassaurus'' ("Qantas Lizard": its name is a homage to Qantas, the LandDownUnder airlines). However, there's another relative discovered in Australia at the start of the XX century, but is known only from a femur: ''[[http://en.wikipedia.org/wiki/Fulgurotherium Fulgurotherium]]'' (the "lightening beast"). Its name is odd because recalls more that of a prehistoric mammal (''"[[UsefulNotes/StockDinosaursNonDinosaurs Megatherium]]"'', ''"[[UsefulNotes/StockDinosaursNonDinosaurs Uintatherium]]"'', ''"[[UsefulNotes/StockDinosaursNonDinosaurs Hyracotherium]]"'', and so on) than that of a dinosaur.

* Partially compensating, several small bipedal ornithischians have been then discovered in other southern continents, the best-known being ''Leaellynasaura amicagraphica''. It was found in 1989 in Australia along with the single lower jaw of the larger ''[[http://en.wikipedia.org/wiki/Atlascopcosaurus Atlascopcosaurus loadsi]]'', so-called from the Atlas-Copco Corporation that funded its excavation. Another Australian "hypsilophodont" described in 1999 is ''Qantassaurus intrepidus'' ("courageous Qantas Lizard": its genus name is a homage to Qantas, the LandDownUnder airlines). However, there's another relative discovered in Australia at the start of the XX century, but is known only from a femur: ''[[http://en.wikipedia.org/wiki/Fulgurotherium Fulgurotherium australe]]'' (the "lightening beast of the South"). Its name is odd because recalls more that of a prehistoric mammal (''"[[UsefulNotes/StockDinosaursNonDinosaurs Megatherium]]"'', ''"[[UsefulNotes/StockDinosaursNonDinosaurs Uintatherium]]"'', ''"[[UsefulNotes/StockDinosaursNonDinosaurs Hyracotherium]]"'', and so on) than that of a dinosaur.

* An even more primitive ornithopod from the same period of ''Callovosaurus'' was the Chinese “hypsilophodont” ''Yandusaurus'', once considered the most basal true ornithopod known to science. It was originally named "Yubasaurus", but since that name was not made official, ''Yandusaurus'' got the precedence. Other “hypsilophodonts" from the same fauna were also too primitive to be real ornithopods. The most scientifically-known is ''[[http://en.wikipedia.org/wiki/Agilisaurus Agilisaurus]]'' ("agile lizard"); others are ''Xiaosaurus'', ''Gongbusaurus'', and former ''Yandusaurus'' species ''Hexinlusaurus''. From Early Cretaceous China comes the enigmatic true-ornithopod ''[[http://en.wikipedia.org/wiki/Jeholosaurus Jeholosaurus]]'' (named after the geological formation it was dug out), whose pointed frontal teeth seem indicating an omnivorous diet. It appears as a prey of the "gliding raptor" ''[[UsefulNotes/PrehistoricLifeBirdlikeTheropods Sinornithosaurus]]'' in Series/PlanetDinosaur.

Among non-hadrosaur/non-''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Iguanodon]]'' ornithopods, the ones you've more chances to see in media are: ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Hypsilophodon]]'' (the prototype of the "hypsilophodonts" aka small-slender members of the Group, pictured above); ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Camptosaurus]]'', ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Dryosaurus]]'' & ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Nanosaurus]]'' (the three iconic hadrosaur predecessors from the Late Jurassic; the first was big and Iguanodon-like, the second was medium-sized and Hypsilophodon-like, the latter was tiny and ''[[UsefulNotes/PrehistoricLifePrimitiveOrnithischians Lesothosaurus]]''-like): ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Tenontosaurus]]'' (looking like it's in the middle between an ''Iguanodon'' and a ''Hypsilophodon'', but with a distinctively long tail); and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Ouranosaurus]]'' (with an evident crest on its back, it's traditionally considered an "iguanodont" but was actually closer to hadrosaurs). Among the other examples, the "iguanodont" ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Muttaburrasaurus]]'' and the "hypsilophodont" ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Leaellynasaura]]'' (both Australian) were portrayed in 1999 by ''Series/WalkingWithDinosaurs'', while ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Orodromeus]]'' and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Thescelosaurus]]'' (both "hypsilophodonts") have had notable ScienceMarchesOn stories. Extremely recent research says even ''Hypsilophodon'' and other animals of this page are too primitive to be true ornithopods.

''Hypsilophodon'' (the animal of the image, no bigger than an adult human) is classically countered against ''Iguanodon'', which is the traditional prototype of the the “[[http://en.wikipedia.org/wiki/Iguanodontia iguanodonts]]” (large/heavy non-hadrosaurian ornithopods). [[ScienceMarchesOn Now scientists have found]] “[[http://en.wikipedia.org/wiki/Hypsilophodont hypsilophodonts]]” is an artificial assemblage, while “iguanodonts” now indicates a natural group including not only the most ''Iguanodon''-like animals but also [[UsefulNotes/PrehistoricLifeHadrosaurs duckbills]], pre-duckbills and also some traditional “hypsilophodontians” like ''Dryosaurus''.

Among non-hadrosaur/non-''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Iguanodon]]'' ornithopods, the ones you've more chances to see in media are: ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Hypsilophodon]]'' (the prototype of the "hypsilophodonts" aka small-slender members of the Group, pictured above); ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Camptosaurus]]'' & ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Dryosaurus]]'' (the two iconic ornithopods from the Late Jurassic; the former was big and Iguanodon-like, the latter small and Hypsilophodon-like): ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Tenontosaurus]]'' (looking like it's in the middle between an ''Iguanodon'' and a ''Hypsilophodon'', but with a distinctively long tail); and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Ouranosaurus]]'' (with an evident crest on its back, it's traditionally considered an "iguanodont" but was actually closer to hadrosaurs). Among the other examples, the "iguanodont" ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Muttaburrasaurus]]'' and the "hypsilophodont" ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Leaellynasaura]]'' (both Australian) were portrayed in 1999 by ''Series/WalkingWithDinosaurs'', while ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Orodromeus]]'' and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Thescelosaurus]]'' (both "hypsilophodonts") have had notable ScienceMarchesOn stories. Extremely recent research says even ''Hypsilophodon'' and other animals of this page are too primitive to be true ornithopods.

[[folder:"Iguanodonts"]]

[[/folder]]

[[folder:"Hypsilophodonts"]]

'''The Never-Ending Story:''' the ''[[http://en.wikipedia.org/wiki/Nanosaurus Nanosaurus]]'' - "''Othnielia''" - "''Drinker''" case

* Travelling in Late Jurassic USA, other than ''Camptosaurus'' the Wildebeest and ''Dryosaurus'' the Gazelle we'd encounter also ''[[RuleOfThree Nanosaurus]]'' the Dik-Dik. Meaning "dwarf lizard", this was indeed a very small animal, 1.5 m long (smaller than an ''Hypsilophodon''), with a very convoluted ScienceMarchesOn story. Discovered during Cope’s and Marsh’s “war”, ''Nanosaurus agilis'' ("agile dwarf lizard") was very commonly-portrayed in old textbooks for having detained the record of “the smallest North-American dinosaur” for almost a century. In 1977 it was described from the same sites a similar animal, ''Othnielia rex'', which was renamed more recently ''Othnielosaurus'' because its type material was not diagnostic. Both curious names derive from [[http://en.wikipedia.org/wiki/Othniel_Charles_Marsh Othniel Charles Marsh]], one of the two scientists who “fought” the Bone-Wars in the XIX century. As it seems, its notorious rivalry with [[http://en.wikipedia.org/wiki/Edward_Drinker_Cope Edward Drinker Cope]] has lasted until today, with another similar animal from the same habitat named ''Drinker nisti'' in 1990 out of spite! Today, all these three genus names are usually considered as junior synonyms of ''Nanosaurus agilis''. Today, the record of "the smallest North-American dinosaur" pertains to a tiny heterodontosaurid found only in 2009, ''[[UsefulNotes/PrehistoricLifePrimitiveOrnithischians Fruitadens]]''. The very fragmentary ''[[http://en.wikipedia.org/wiki/Laosaurus Laosaurus celer]]'' ("speedy fossil lizard", described in USA in the same period of ''Nanosaurus'') has been involved in this taxonomic tangle as well, with its remains often found mixed with those of ''Dryosaurus''.

'''Chinese Gazelle:''' ''[[http://en.wikipedia.org/wiki/Yandusaurus Yandusaurus]]''

* An even more primitive ornithopod from the same period of ''Callovosaurus'' was the Chinese “hypsilophodont” ''Yandusaurus'', once considered the most basal true ornithopod known to science. It was originally named "Yubasaurus", but since that name was not made official, ''Yandusaurus'' got the precedence. Other “hypsilophodonts" from the same fauna were also too primitive to be real ornithopods. The most scientifically-known is ''[[http://en.wikipedia.org/wiki/Agilisaurus Agilisaurus]]'' ("agile lizard"); others are ''Xiaosaurus'', ''Gongbusaurus'', and former ''Yandusaurus'' species ''Hexinlusaurus''. From Early Cretaceous China comes the enigmatic true-ornithopod ''[[http://en.wikipedia.org/wiki/Jeholosaurus Jeholosaurus]]'' (named after the geological formation it was dug out), whose pointed frontal teeth seem indicating an omnivorous diet. It appears as a prey of the "gliding raptor" ''[[UsefulNotes/PrehistoricLifeBirdlikeTheropods Sinornithosaurus]]'' in Series/PlanetDinosaur.

'''Icy Amnesia:''' the "Polar Hypsilophodon"

* Let’s not forget the “Mysterious Antarctic Dino”. In year 1987, just one year after the ankylosaur named ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Antarctopelta]]'' in 2006, [[https://www.cambridge.org/core/journals/antarctic-science/article/abs/an-ornithopod-dinosaur-from-the-late-cretaceous-of-west-antarctica/460B7DC007270FB20C11EA3081CDD381 the second Antarctic dinosaur was found]], described as a “polar hypsilophodont”; the thing is, it has had an even worse fate than the ankylosaur itself. At least, after 20 years of waiting, the latter ''has'' received a name; the polar "hypsy" ''has yet to wait a formal naming and description'', and sadly seems to be almost forgotten today. In classic textbooks the "polar Hypsilophodon" is usually depicted with a shape very similar to the real ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Hypsilophodon]]'', but being it still-undescribed, we cannot say much about its life apart from the fact that was Late Cretaceous like its neighbor ''Antarctopelta''.

'''Plane-Traveler:''' ''[[http://en.wikipedia.org/wiki/Qantassaurus Qantassaurus]]''

* Partially compensating, several small bipedal ornithischians have been then discovered in other southern continents, the best-known being ''Leaellynasaura amicagraphica''. It was found in 1989 in Australia along with the single lower jaw of the larger ''[[http://en.wikipedia.org/wiki/Atlascopcosaurus Atlascopcosaurus loadsi]]'', so-called from the Atlas-Copco Corporation that funded its excavation. Another Australian "hypsilophodont" described in 1999 is ''Qantassaurus intrepidus'' ("courageous Qantas Lizard": its genus name is a homage to Qantas, the LandDownUnder airlines). However, there's another relative discovered in Australia at the start of the XX century, but is known only from a femur: ''[[http://en.wikipedia.org/wiki/Fulgurotherium Fulgurotherium australe]]'' (the "lightening beast of the South"). Its name is odd because recalls more that of a prehistoric mammal (''"[[UsefulNotes/StockDinosaursNonDinosaurs Megatherium]]"'', ''"[[UsefulNotes/StockDinosaursNonDinosaurs Uintatherium]]"'', ''"[[UsefulNotes/StockDinosaursNonDinosaurs Hyracotherium]]"'', and so on) than that of a dinosaur.

----

'''Feminine Dinosaurs:''' ''[[http://en.wikipedia.org/wiki/Gasparinisaura Gasparinisaura]]''

* About South American discoveries, apart from the enigmatic ''Loncosaurus'' (found as well in the early XX century but described from a single femur mixed with a theropod tooth), there are few non-hadrosaur ornithopods found in the 1990s or later, the largest one being the 6 m long ''[[http://en.wikipedia.org/wiki/Macrogryphosaurus Macrogryphosaurus]]''. Another is meaningfully named ''Notohypsilophodon'', the "Southern Hypsilophodon". Curiously, one small South American ornithopod described in 1996 [[FollowTheLeader has got]] a feminine name reminescent of ''Leaellynasaura'': ''Gasparinisaura'' ("Gasparini's lizard"). Since that other small ornithischians around the world have received the suffix "-saura", for example "Bugenasaura" (now regarded as a synonym of ''Thescelosaurus'') and, last example, ''[[http://en.wikipedia.org/wiki/Trinisaura Trinisaura]]'', found in Antarctica in the earliest part of 2013 (this one has immediately received a name). Well, [[TheUnfairSex Unfair Sex]] -related names do fit better for [[AnimalMotifs these graceful “gazelle dinos”]] rather than the badass-looking ([[AnimalMotifs and very masculine]]) ankylosaurs.

----

Among non-hadrosaur/non-''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Iguanodon]]'' ornithopods, the ones you've more chances to see in media are: ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Hypsilophodon]]'' (the prototype of the "hypsilophodonts" aka small-slender members of the Group); ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Camptosaurus]]'' & ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Dryosaurus]]'' (the two iconic ornithopods from the Late Jurassic; the former was big and Iguanodon-like, the latter small and Hypsilophodon-like): ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Tenontosaurus]]'' (looking like it's in the middle between an ''Iguanodon'' and a ''Hypsilophodon'', but with a distinctively long tail); and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Ouranosaurus]]'' (with an evident crest on its back, it's traditionally considered an "iguanodont" but was actually closer to hadrosaurs). Among the other examples, the "iguanodont" ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Muttaburrasaurus]]'' and the "hypsilophodont" ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Leaellynasaura]]'' (both Australian) were portrayed in 1999 by ''Series/WalkingWithDinosaurs'', while ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Orodromeus]]'' and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Thescelosaurus]]'' (both "hypsilophodonts") have had notable ScienceMarchesOn stories. Extremely recent research says even ''Hypsilophodon'' and other animals of this page are too primitive to be true ornithopods.

[[/folder]]

* Let’s not forget the “Mysterious Antarctic Dino”. In year 1987, just one year after the ankylosaur named ''[[UsefulNotes/PrehistoricLifeAnkylosaurs Antarctopelta]]'' in 2006, [[https://www.cambridge.org/core/journals/antarctic-science/article/abs/an-ornithopod-dinosaur-from-the-late-cretaceous-of-west-antarctica/460B7DC007270FB20C11EA3081CDD381 the second Antarctic dinosaur was found]], described as a “polar hypsilophodont”; the thing is, it has had an even worse fate than the ankylosaur itself. At least, after 20 years of waiting, the latter ''has'' received a name; the polar "hypsy" ''has yet to wait a formal naming and description'', and sadly seems to be almost forgotten today. In classic textbooks the "polar Hypsilophodon" is usually depicted with a shape very similar to the real ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Hypsilophodon]]'', but being it still-undescribed, we cannot say much about its life apart from the fact that was Late Cretaceous like its neighbor ''Antarctopelta''.

'''The Never-Ending Story:''' the ''[[http://en.wikipedia.org/wiki/Nanosaurus Nanosaurus]]'' - "Othnielia" - "Drinker" case

'''Aquatic Dinosaur?:''' ''[[http://en.wikipedia.org/wiki/Lurdusaurus Lurdusaurus]]''

'''The Never-Ending Story:''' ''[[http://en.wikipedia.org/wiki/Nanosaurus Nanosaurus]]''

* Travelling in Late Jurassic USA, other than ''Camptosaurus'' the Wildebeest and ''Dryosaurus'' the Gazelle we'd encounter also ''[[RuleOfThree Nanosaurus]]'' the Dik-Dik. Meaning "dwarf lizard", this was indeed a very small animal, 1.5 m long (smaller than an ''Hypsilophodon''), with a very convoluted ScienceMarchesOn story. Discovered during Cope’s and Marsh’s “war”, ''Nanosaurus agilis'' ("agile dwarf lizard") was very commonly-portrayed in old textbooks for having detained the record of “the smallest North-American dinosaur” for almost a century. In 1977 it was described from the same sites a similar animal, ''Othnielia rex'', which was renamed more recently ''Othnielosaurus'' because its type material was not diagnostic. Both curious names derive from [[http://en.wikipedia.org/wiki/Othniel_Charles_Marsh Othniel Charles Marsh]], one of the two scientists who “fought” the Bone-Wars in the XIX century. As it seems, its notorious rivalry with [[http://en.wikipedia.org/wiki/Edward_Drinker_Cope Edward Drinker Cope]] has lasted until today, with another similar animal from the same habitat named ''Drinker nisti'' in 1990 out of spite! Today, all these three genus names are usually considered as junior synonyms of ''Nanosaurus agilis''. Today, the record of "the smallest North-American dinosaur" pertains to a tiny heterodontosaurid found only in 2009, ''[[UsefulNotes/PrehistoricLifePrimitiveOrnithischians Fruitadens]]''. The very fragmentary ''[[http://en.wikipedia.org/wiki/Laosaurus Laosaurus celer]]'' ("speedy fossil lizard", described in USA in the same period of ''Nanosaurus'') has been involved in this taxonomic tangle as well, with its remains often found mixed with those of ''Dryosaurus''.

----

'''Pietrified Nests?:''' ''[[http://en.wikipedia.org/wiki/Orodromeus Orodromeus]]''

* There were other “hypsilophodontians” from Late Cretaceous North America that were smaller and lived slightly earlier than ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Thescelosaurus]]''. ''Orodromeus makelai'', meaning "Makela's runner of the (Egg) Mountain", was discovered in Montana in year 1988 by Jack Horner and his assistant Robert [[ExactlyWhatItSaysOnTheTin Makela]] in the same site in which they had found ''Maiasaura peeblesorum'' eight years before. They noted some small unusually spiral-shaped nests full of eggs containing fossilized embryos, next to the bigger & more famous ''Maiasaura'' ones, which they attributed to ''Orodromeus'': as the bones inside those eggs were already well-formed, they said that the orodromeus' hatchlings were more independent after birth than the maiasaura's ones. ScienceMarchesOn however, and later it was found that those eggs/embryos were from the theropod ''[[UsefulNotes/StockDinosaursSaurischianDinosaurs Stenonychosaurus]]'' instead. The ironical thing is, fossils of stenonychosaurs (aka the "troodons") were discovered as well around those putative ''Orodromeus'' nests, but it was thought that they were actually preying on Orodromeus nestlings: an astonishingly similar story to the “Oviraptor robbing Protoceratops' eggs”. Found in 2007, its relative ''[[http://en.wikipedia.org/wiki/Oryctodromeus Oryctodromeus]]'' ("digging runner") lived quite a bit earlier than the [[NamesTheSame similar-named]] ''Orodromeus'' in Middle Cretaceous, but has also shown the first proof of digging behavior among non-avian dinosaurs: its skeleton has been found inside a fossilized burrow. Another relative found in Alberta is known since the start of the XX century: ''[[http://en.wikipedia.org/wiki/Parksosaurus Parksosaurus]]'' ("William Parks' lizard", sometimes misspelled "''Parkosaurus''"). Similar in size and shape to ''Orodromeus'' but living few million years later, it could be actually closer to ''Thescelosaurus'' (which lived even later), and has recently become the namesake of its own family of ornithopods, the Parksosaurids. ''[[http://en.wikipedia.org/wiki/Zephyrosaurus Zephyrosaurus]]'' ("lizard of the western wind"), lived earlier than all these, in the Early Cretaceous Montana: it could have met ''[[UsefulNotes/StockDinosaursSaurischianDinosaurs Deinonychus]]'' in real life, and possibly was one of its preys.

'''Named after a Girl:''' ''[[http://en.wikipedia.org/wiki/Leaellynasaura Leaellynasaura]]''

* If you’ve seen the fifth episode of ''Walking With Dinosaurs'', you’ll already have the idea what we’re talking about. Dinosaur names are often thought bizarre-sounding, and this animal certainly does match the commonplace very well, like its bigger compatriot ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Muttaburrasaurus]]''. This one is called from the village of Muttaburra in Queensland, Australia, where its only skeleton was found in 1981; ''Leaellynasaura amicagraphica'' was named after the daughter of its discoverers, Leaellyn. Another little-known australian dinosaur, ''[[UsefulNotes/PrehistoricLifeBirdlikeTheropods Timimus]]'', was named after Leaellyn's brother, Tim. It has ''mimus'' at the end because was originally thought an ornithomimosaur. ''Leaellynasaura'' (sometimes misspelled "''Leaellynosaura''") owes well its feminine suffix ''saura'', just like the hadrosaur ''Maiasaura'' which means “good-mother lizard”. Together with the shorter-named but equally bizarre-sounding ankylosaur ''Minmi'', these are the most well-known Aussie Dinos. First-found in 1989, ''Leaellynasaura'' was a small (1 m long) bipedal animal similar to ''Hypsilophodon''. Once considered an “hypsilophodontian”, even its ornithopod status is disputed today, and is now generally regarded as a more basal ornithischian. The fossil material attributed to ''Leaellynasaura'' [[http://espace.library.uq.edu.au/view/UQ:320937 has been recently revised]]. Fossils discovered in Australia in the 2000s indicate presence of a small Early Cretaceous ornithischian with tail 3 times longer that its own body (even more than the ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Tenontosaurus]]'' tail); whether this is the same taxon as ''Leaellynasaura'' or not remains to be seen. The discover of ''Muttaburrasaurus'', ''Minmi'', and ''Leaellynasaura'' in the 1980s made sensation in Australia, because very few dinosaurs were known before in the LandDownUnder, all fragmentary. ''Muttaburrasaurus'', like ''Minmi'', still is one of the most complete dinosaurs found there; ''Leaellynasaura'' ‘s skeletons are more incomplete, but the latter's importance was due to having contributed to enforce the “warm-blooded dinosaurs” hypothesis even more. In Early Cretaceous, Australia was not the temperate/tropical/desertic country we know today, but a colder world with warm summers but cold winters - because was much closer to the South Pole. How could such a small, clearly non-migratory animal like this manage to survive that icy winter? The only explanation was: ''Leaellynasaura'' was warm-blooded. Furthermore, its unusually big eyes could have been used to see throughout the darkness of the polar winter. All these arguments have been discussed in ''Series/WalkingWithDinosaurs'', in which a family of ''Leaellynasaura'' makes the main characters. The show also portrayed ''Muttaburrasaurus'', as a migrating animal that flees the winter in herd like caribous; it also added to it speculative nasal sacs to make loud sounds (like what's been hypothized for some hadrosaurs), but we don't have direct evidence for this.

'''The Never-Ending Story:''' ''[[http://en.wikipedia.org/wiki/Nanosaurus Nanosaurus]]''

* Travelling in Late Jurassic USA, other than ''Camptosaurus'' the Wildebeest and ''Dryosaurus'' the Gazelle we'd encounter also ''[[RuleOfThree Nanosaurus]]'' the Dik-Dik. Meaning "dwarf lizard", this was indeed a very small animal, 1.5 m long (smaller than an ''Hypsilophodon''), with a very convoluted ScienceMarchesOn story. Discovered during Cope’s and Marsh’s “war”, ''Nanosaurus agilis'' ("agile dwarf lizard") was very commonly-portrayed in old textbooks for having detained the record of “the smallest North-American dinosaur” for almost a century. In 1977 it was described from the same sites a similar animal, ''Othnielia rex'', which was renamed more recently ''Othnielosaurus'' because its type material was not diagnostic. Both curious names derive from [[http://en.wikipedia.org/wiki/Othniel_Charles_Marsh Othniel Charles Marsh]], one of the two scientists who “fought” the Bone-Wars in the XIX century. As it seems, its notorious rivalry with [[http://en.wikipedia.org/wiki/Edward_Drinker_Cope Edward Drinker Cope]] has lasted until today, with another similar animal from the same habitat named ''Drinker nisti'' in 1990 out of spite! Today, all these three genus names are usually considered as junior synonyms of ''Nanosaurus agilis''. Today, the record of "the smallest North-American dinosaur" pertains to a tiny heterodontosaurid found only in 2009, ''[[UsefulNotes/PrehistoricLifePrimitiveOrnithischians Fruitadens]]''. The very fragmentary ''[[http://en.wikipedia.org/wiki/Laosaurus Laosaurus celer]]'' ("speedy fossil lizard", described in USA in the same period of ''Nanosaurus'') has been involved in this taxonomic tangle as well, with its remains often found mixed with those of ''Dryosaurus''.

----

Among non-hadrosaur/non-''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Iguanodon]]'' ornithopods, the ones you've more chances to see in media are: ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Hypsilophodon]]'' (the prototype of the "hypsilophodonts" aka small-slender members of the Group); ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Camptosaurus]]'' & ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Dryosaurus]]'' (the two iconic ornithopods from the Late Jurassic; the former was big and Iguanodon-like, the latter small and Hypsilophodon-like): ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Tenontosaurus]]'' (looking like it's in the middle between an ''Iguanodon'' and a ''Hypsilophodon'', but with a distinctively long tail); and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Ouranosaurus]]'' (with an evident crest on its back, it's traditionally considered an "iguanodont" but was actually closer to hadrosaurs). Among the other examples, the "iguanodont" ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Muttaburrasaurus]]'' and the "hypsilophodont" ''Leaellynasaura'' (both Australian) were portrayed in 1999 by ''Series/WalkingWithDinosaurs'', while ''Orodromeus'' and ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Thescelosaurus]]'' (both "hypsilophodonts") have had notable ScienceMarchesOn stories. Extremely recent research says even ''Hypsilophodon'' and other animals of this page are too primitive to be true ornithopods.