Friday, April 25, 2014

Top 10 Prehistoric Creatures pictured accidentally



You know, it’s easy to see how we’ve misinterpreted fossils.  It’s difficult for any part of an animal to fossilize, so complete specimens are rare and really special.  So inaccurate palaeoart is inevitable, and really not surprising at all.  Then there are the times when reconstructions accidentally depict a different animal entirely unintentionally. We all know about how Tyrannosaurus was originally reconstructed on Allosaurus and Apatosaurus on Camarosaurus, but they’re not alone. Sometimes it’s because of misidentification, and sometimes it’s simply due to laziness in paleontological reconstructions.  Here are the top 10 Prehistoric Animals people picture when they try to picture a different animal (there has to be a specific word for this phenomenon. I’m sure there’s one in German or something).


#10. Pterodactylus =Ludodactylus

Now, the first misconception about Pterodactylus (often called simply “Pterodactyl”) is that it’s a dinosaur in the first place. Pterosaurs have never been classified under true dinosaurs, but their relationship to dinosaurs is still being debated.  The consensus now is that they’re archosaurs closely related to dinosaurs, but diverged in the later early Triassic and evolved into recognizable flying forms at the end of the Triassic.  The other misconception is their appearance; say the word Pterodactyl and you invoke a long-snouted, skin-winged animal, which is close enough, but said snout is full of sharp teeth and a long head crest. 




This is a chimera. The name and teeth come from Pterodactylus itself, discovered in the 1780s by Cosimo Collini based on a well-preserved specimen from Bavaria. Colllini assumed it was an amphibian that used the long finlike fingers as paddles, swimming the lost European sea that the limestone came from.   In the 1800s it was correctly identified as a flying reptile by the legendary anatomist Georges Cuvier.  So from then on, the prehistoric skies of 19th century books were full of these creatures, along with other European pterosaurs of the Jurassic Dimorphodon and Rhamphorhynchus. 

 by Giuliano Fornari
Everything changed with the discovery by our friend Othniel Charles Marsh of a new pterosaur, larger and crowned with a long crest, in Kansas in 1870. Toothless, crested (this feature is sexually dimorphic, with the long-crested males being the archetype) , and with a 20-foot wingspan, this flying reptile became an icon of prehistory. It has become to Pterosaurs what Apatosaurus and Tyrannosaurus are to Dinosaurs, unrivaled in its iconic status. However, it’s been called Pterodactyl and portrayed with a beak full of death throughout the 20th century and indeed into the 21st, despite the name referring to a different animal, a name literally meaning “winged toothless”.  However in 2003, a coincidental pterosaur was found matching the depiction of pterosaurs of the past century.

Also from the Cretaceous (albiet 40 million years earlier than Pteranodon), this pterosaur was named by Dr. Eberhard Frey of the Karlsruhe museum (along with his Karlsruhe college Marie Celine Buchy and Portsmouth University’s David Martill), Frey and Buchy, by the way, have been off and on working on a giant Mexican pliosaur nicknamed “The Monster of Aranberri” that I’ve mentioned before.   The very word Ludodactylus is mixed Latin-Greek, meaning “play finger” named for its resemblance to toys made of Pterosaurs.  It’s a relative of Pteranodon, but is more derived and is part of a toothy, crested, very successful group of sea pterosaurus of the Cretaceous called Ornithocheirids.  Living in the Crato Formation, near Ceara, Brazil, it shared the air with other fish-eating pterosaurs like the crestless Cearadactylus (featured in the novel Jurassic Park), long-winged Arthurdactylus (named after Sir Conan Doyle, who played a colony of demonic Pterodactylus in his classic The Lost world), Basileodactylus (which may be the senior synonym of Ludodactlyus, or a junior synonym of Colobrynchus or Anhanguera), the big toothless (and crestless) Lacusovagus, and the giant-crested Tupandactylus

#9 Dimetrodon=Secondontosaurus

Speaking of prehistoric animals that are commonly mistaken for dinosaurs, Dimetrodon has likewise been lumped in with the Mesozoic animals, despite not only being separated from the first dinosaur by more time than between humans and Tyrannosaurus ,but also not even related to dinosaurs and being ancestral to mammals. Dimetrodon, discovered by Marsh’s archrival Edward Drinker Cope, is also a prehistoric icon, and was probably lumped in with dinosaurs by its appearance in Sinclair Oil’s Dinosaur Exhibit at the 1933 Chicago World’s fair.  Dimetrodon bears a unique skull, with its 3-types of specialized teeth, and it’s instantly recognizable by most paleontologists.

However, it’s this skull that everyone gets wrong.  You see, it’s very easy to get that skull wrong when you don’t look at it. The first analogy people have with pelycosaurs are similarly proportioned reptiles of today, despite their total lack of relation. Lizards and crocodiles have been used as models for dinosaurs, so it’s only natural that they turn to them for the sprawling, lizard-shaped Dimetrodon.  Indeed, in the films One Million BC (1940), The Lost World remake (1960), and Journey to the Center of the Earth (1949), dimetrodons not only appeared as dinosaurs but also were depicted by baby alligators (in both 1940 and 1960 films), and rhinoceros  iguanas (1949).

Oddly enough, Cope also found another pelycosaur in his expeditions to the Texas Red Beds. He identified it as a specimen of Theropleura (Cope’s name for Marsh’s Ophiacodon), an amphibious predator, but once again he was undone by Marsh. Marsh’s student Samuel W. Williston, who helped discover Apatosaurus and Allosaurus, identified this particular morph of “Theropleura” was a distinct species, naming it Secondontosaurus for its flattened teeth in contrast to Ophiacodon’s conical piscivore teeth.  The great tetrapod paleontologist Alfred Romer finally put two and two together, discovering that a specimen of Dimetrodon was actually the body of Williston’s pelycosaur.

Secondontosaurus lived in the same period and region as Dimetrodon, as well as the same shape of body complete with tall dorsal fin, but the head is what makes its distinct. It has a slender, slightly curved skull resembling a monitor lizard or crocodilian with uniform cutting teeth instead of the deep skull armed with a pattern of sharp incisors, huge fangs, and smaller cutting teeth of Dimetrodon.  This long, narrow type of skull indicates a unique lifestyle distinct from Dimetrodon and Ophiacodon.  The great Robert Bakker described it as the “Fox-Faced Finback”, and suggested it hunted small burrowing reptiles and amphibians. http://hmnspaleo.blogspot.com/2007/10/secodontosaurus-fox-faced-finback.html While Dimetrodon’s skull was evolved to tear through the flesh of huge animals like Eryops, Diadectes, and Edaphosaurus, Secondontosaurus’ light and narrow skull evolved to slip into tunnels and delicately snatch the residents.   In 2006, Nancy Bowen of the Huston Museum found a new specimen, the first found in 70 years. Hopefully more information is coming on this specimen.

#8. Spinosaurus=Acrocanthosaurus and Arizonasaurus

Back before Jurassic Park 3 tried to push Spinosaurus as the ultimate dinosaur, the genus was only known for the sail. Back in 1912, the great paleontologist Ernst Stromer and his collector and friend Richard Markgraf discovered a great deal of North African dinosaurs, as I mentioned in the paleontology wishlist.  As I said before, they were able to publish their finds and Stromer identified a large number of Egyptian species before 1944, when the RAF and USAF’s infamous destruction of the German cities claimed Stromer’s collection as their victims. 

by Susan Swan
With the original finds missing and the Cold War restricting further international expeditions, paleontologists could only extrapolate from Stromer’s descriptions. In this case, it was the massive backbone and unique spinal sail and long clawed arms of Spinosaurus and the dangerous teeth of Carcharodontosaurus found in close vicinity to each other. This caused a confusion of the species-for almost an entire century, Spinosaurus became described as an Allosaur with a fin. In the 70s, the discovery of Baryonyx, a croc-snouted close relative didn’t cause a re-evaluation of the reconstruction, but perversely both Baryonyx and Spinosaurus were occasionally depicted as quadrupeds.  This only changed in the decade of 1995 to 2005, where 5 new specimens revealed an animal far more similar to Baryonyx than Allosaurus.

 by John Sibbick
The conflation wasn’t just a chimera, but because of another theropod described in 1950-Acrocanthosaurus. This huge, robust American predator was correctly identified as a relative of Allosaurus, and it possessed elongated spinal processes-not to the same extent as the Dimetrodon-esque sail of Spinosaurus, but certainly forming a long, low back crest.  Thus, Acrocanthosaurus, due to physiology and temporal range, became the missing link between Allosaurus and Spinosaurus.

Ironically, there was a big extinct predator with a tall sail, big Allosaur-like head, and the ability to switch between two and four legs, but it was no dinosaur.  The complete specimen was found in 2002 of the rauisuchid (remember Teratosaurus?) Arizonasaurus. While only the size of an American alligator, Arizonasaurus and its European sister species (down to the sail) Ctenosauriscus were the top predators of the early and middle Triassic as part of the successful family of rauisuchids. Rauisuchids had long enough forelimbs to be effective quadrupeds, but the relative sizes of the pairs of limbs allowed them to walk or run erect bipedally like a dinosaur.  So when illustrators of the 20th century portrayed Spinosaurus, they were portraying Arizonasaurus.

#7 Velociraptor=Utahraptor

Velociraptor has become synonymous with the classic 1993 film Jurassic Park. They were the breakout stars, symbolizing the Dinosaur Renaissance’s birdlike, intelligent, and vigorous new image of dinosaurs. Just say the word Velociraptor, and everyone will flash to Jurassic Park’s hyperintelligent predators. Of course, when you show the same people a contemporary, accurate rendition of Velociraptor, they will be confused by the dog-sized, long-feathered, slender-snouted little predator that’s “only” as fast as a lion and as smart as a bird.

This was a multi-step process in the ways of the corruption. It all started when the great paleoartist and paleontological writer Greg Paul, a “lumper” (any scientist who takes the position that various species and genera are co-specific or co-generic, as opposed to their opposite adversaries “splitters”) wrote his classic 1988 book Predatory Dinosaurs of the World. In it, he “lumped” all the known dromeosaurs into the single genus Velociraptor. So, the big early Cretaceous dromeosaur Deinonychus became a species of Velociraptor-Velociraptor antirrhopus. Michael Crichton, in researching for his novel Jurassic Park, used Paul’s book. So, the main villains of the novel were the classic Tyrannosaurus and the then-obscure “Velociraptor”, now augmented with super intelligence and speed.

When Steven Spielberg adopted the best-selling novel, he added one last twist-the mastiff-sized Deinonychus was inflated to the size of humans while the big female leader becoming the size of a bear.  Coincidentally, just as the film became a hit, paleontologist Jim Kirkland and his partner Robert Gaston discovered a new, giant dromeosaur-Utahraptor. Kirkland reportedly called the film’s advisors Robert Bakker and Jack Horner with the message “We’ve found Spielberg’s raptor”.  Indeed, Utahraptor became the image of Velociraptor and only recently became successful in its own name, eclipsing Velociraptor in the public eye. 

As a coda, new discoveries continued, making the “raptors” obsolete once and for all. In 1999, a tiny dromeosaur from the now-classic Yixian formation, Sinornithosaurus, was found with well-preserved, undeniably feathered integument.  In 2007, the limbs of Sinornithosaurus were compared with those of Velociraptor-the jury was out; Velociraptor very probably had a full coat of feathers from head to tail to the fingers. Dromeosaurs, it seems, used clawed wings to capture and wound prey. 

#6 Ankylosaurus=Euoplocephalus and Edmontonia

Ask someone to name an armored dinosaur, and three dinosaurs will inevitably come up-the frilled Triceratops, plated Stegosaurus, and the tank of tanks, Ankylosaurus.  Ankylosaurus usually has unique look-a horned head, a wide, turtlelike body protected by flattened scutes on the back and long spines jutting from the spines, and a big bilobed tail club used to bludgeon predators.  In fact, only ten years ago has the true form and size of Ankylosaurus been known. For almost a century, Ankylosaurus has been a chimera of two great Canadian species to form an archetypical American dinosaur.

by Rod Ruth
In 1908, Barnum Brown of the American Museum returned to the beds of Montana where he found Tyrannosaurus. Not only did he find the skull and neck of his legendary genus, but also a new animal. The skull and body were of a wide, low-slung animal with a coat of osteoderms on its back. In 1910, he found more in Alberta, including the club.  Around the same time, however, Lawrence Lambe of the Geological Survey of Canada (affiliated with the Canadian Museum of Nature)  discovered various new ankylosaurus-Dyoplosaurus, Euoplocephalus, and Scolosaurus (which have been grouped into Euoplocephalus by some, but split again by other paleontologists), and complete specimens of Euoplocephalus and Scolosaurus.

In 1915, the American museum found a specimen of Edmontonia, assigning it to the dubious tooth taxon Palaeoscincus, and it was the basis for Charles Knight’s illustration for the Field Museum. In 1933, Charles R. Knight made a series of 28 murals (as previously mentioned in my Field Museum article), and one included Ankylosaurus among groups of hadrosaurs. The American Museum’s “Palaeoscincus” proved to be in better condition than its Ankylosaurus, so it provided the basis for the reconstruction and so became introduced into popular culture. Palaesocincus survived into the 80s before being acknowledged as Edmontonia, while Ankylosaurus had received a makeover.

by Darlene Geiss
In 1947, Ankylosaurus received a facelift. Rudolph Zallinger’s classic Age of Reptiles mural (as previously mentioned in my Yale Peabody article) featured new poses and depictions of dinosaurs that lasted for decades. At the end of the mural, a rather squat, toadlike Ankylosaurus sat under the shadow of Tyrannosaurus.  This became the definitive model of Ankylosaurus with subsequent art, including more by Zallinger and some by the great Zdenek Burian using that model.  In 1964, Sinclair Oil co. redid its classic dinosaur exhibit from 1933, using Zallinger’s reconstructions rather than Knight’s.  From then on, that was the model.

 by Rudolph Zallinger
In the 1980s came the Dinosaur Renaissance. Canada’s dinosaurs were re-examined and quickly took the fore. Euoplocephalus became the ankylosaur star, although mostly relabeled Ankylosaurus.  In this era, Ankylosaurus was either a modified version of Euoplocephalus or a slightly more realistic variation on the 50’s turtle form. Walking Dinosaurs, for example, used characteristics of both. Sometimes Ankylosaurus would show up just as a relabeled Euoplocephalus. To quote artist and blogger Tricia Arnold-"And I can't help but suspect it's because Euoplocephalus, while harder to pronounce, is way easier to draw"

 by Bernard Long

However, in 2004, ankylosaur specialist Kenneth Carpenter finally did a re-assesment of Ankylosaurus material. The result was a shorter, slimmer animal, with flattened osteoderms spaced a few inches apart and an oval tail club. http://www.nrcresearchpress.com/doi/abs/10.1139/e04-043#.U0wIlVegzrk

Here’s a nice overview of Ankylosaurus through the ages http://pseudoplocephalus.blogspot.com/2011/01/ankylosaurus-through-ages.html

#5 Brachiosaurus=Giraffititan

Brachiosaurus has become a sort of stock dinosaur. If you see Diplodocus or Allosaurus, you can probably bet that Brachiosaurus isn’t far behind. First discovered near Fruita, Colorado in 1900 by the Field Museum’s Elmer Riggs, it was one of the first specimens acquired by Chicago. The neckless, headless skeleton was clearly a sauropod, but with long humeri, deep ribs, and a short tail. A skull was discovered nearby, but it was badly preserved and re-assigned to Apatosaurus (likewise, still at the museum, albeit mostly reconstructed by casts of better-preserved fossil bones). Riggs dubbed it Brachiosaurus altithorax, an animal only matched by the Carnegie Museum’s Apatosaurus and Diplodocus for spectacle.





In 1914, the Humboldt Museum’s own dinosaur chief, Werner Janesch, discovered a vast quarry in Lindi in German East Africa (now Tanzania). The biggest and best-preserved of his sauropods was a big, long-armed gracile sauropod, which he named Brachiosaurus branchai. He found multiple specimens, and pieced them together back in Berlin. The mount remains one of the largest in the world, surviving the wars and still dominating the museum hall. This magnificent composite mount became the basis for all depictions of Brachiosaurus, including those of Zdenek Burian and Rudolph Zallinger.  The long neck and short-snouted, tall-crested head was composited with Riggs’ specimen to recreate the American animal.


Fairly straightforward, right? This arrangement lasted a century. Then in 1998, the Denver museum’s (now at the Utah State Museum) Kenneth Carpenter and Virginia Tidwell reconstructed the skull Riggs identified as a brontosaur.  It turned out to be a Brachiosaurus-similar to Janesch’s, but longer and longer. While disarticulated from the body, it was still from the Garden Park quarry, and probably belonged to the same species. Meanwhile, Gregory S Paul, in a rare moment of splitting (his only other was the breaking up of Iguanodon, which is another story) erected a new genus for  the African brachiosaur; Giraffitian.  Dinosaur taxonomist George Olshevsky and later Manchester University’s sauropod expert Michael Taylor agreed, placing it as a sister species to Brachiosaurus.


The unintended result is that all Brachiosaurus depictions (since the US holds a majority in dinosaur authors and artists) are based on Giraffitan. Fortunately, Brachiosaurus in art can be either genus if the drawing isn’t too detailed or if it has slightly different proportions, so it’s not as egregious as the other mistakes in this list.

There are other former members of Brachiosaurus as well; in Portugal, the Lourinha formation is nearly identical to the Morrison and so they have a brachiosaur. This one is called Lusotitan, but is not as well preserved as the American or African genera. Another species, Brachiosaurus nougaredi, was found in Cretaceous strata in Algeria. (more here http://www.paleoglot.org/files/Lapparent_60.pdf http://svpow.com/2009/11/24/more-out-than-in/)  Most of the skeleton is lost or poorly preserved, but what remains suggests a titanosaur or brachiosaur of absolutely colossal size.


#4. Mammuthus primigenus=Mammuthus
Say the word mammoth. Think about what the word evokes in your mind. Most likely you’ll be thinking of a giant prehistoric elephant, covered in thick hair, towering over other elephants.  Mammoth is sometimes preceded by the term wooly, although most times the word mammoth is used, wooly is implied.  After all, there’s no other mammoths, right?

Wooly Mammoths are by far the best known of prehistoric elephants. They ranged from York eastwards to New York, conquering the glacial sheets. They’ve been preserved by big rugged teeth, huge curved tusks, and even complete mummies. They appear in myth and legend across the Arctic circle, and archaeological finds show that mammoths provided food, clothes, tools and shelter for the humans that moved into the north. The type species for Mammuthus is the wooly mammoth Mammuthus primigenus. The species was identified as a prehistoric elephant by the aforementioned Georges Cuvier and then named by  Göttingen’s eminent physician and naturalist Johann Blumenbach in 1799 as a species of elephant, and assigned to its present genus by the great naturalist Joshua Brookes in 1828.


Wooly mammoths were indeed the last mammoths to go extinct, and by far the most successful, but they weren’t the only species, and they weren’t the largest. Wooly mammoths may be the most common fossil mammoths found, but If you look at a wooly mammoth skeleton carefully, you will realize that it’s not any bigger than an Asian elephant. It’s still imposing and was usually the largest animal in its environment, but it was not mammoth for a mammoth.  

Here’s a good rundown of the mammoth species: http://www.cosmosmagazine.com/features/mammoths/

The first mammoth species wasn’t wooly at all-in the Pliocene savannas of Africa, it was probably only distinguished from other elephants by the shape of the skull and tusks. Most likely, this Mammuthus subplanifrons coexisted with Australopithecus and other early savanna apes, as well as other species of elephants and deinotheres.   Later in the Pliocene, it was supplanted by Mammuthus africanavus. Like the Ancestral Mammoth, the African Mammoth was slightly smaller than the African elephant and it’s very unlikely to have had much hair.  Interestingly enough, as soon as mammoths leave Africa, they go extinct in Africa. Did the true elephants replace them?





by Charles Knight
A poorly known species, Mammuthus rumanus has been found in Eastern Europe around the same time as the similarly obscure African mammoth, and either produced the next species Mammuthus meridionalis. The Southern mammoth ranged from Central Asia to England in from the early Pleistocene to the later interglacials. Its teeth were adapted to eating foliage, their tusks shorter and straighter, but they were larger than African elephants. These big successful mammoths managed to cross across into North America, and while the they were succeeded in Eurasia by the Steppe Mammoth, the Americans evolved into a separate species, the Columbian mammoth.

by Jagroar, Deviantart user
The steppe mammoth, Mammuthus trogontherii had a smaller skull and larger tusks than the Southern Mammoth, living until the late Pleistocene in a range from Britain to Hokkaido. The teeth are far more specialized-this animal lived mostly on vast grasslands of Eurasia, giving the species its name.  This animal was huge-the average is larger than an African bull elephant, and one found on the Songhua (tributary of the Amur) river was 18 feet tall and 30 feet long. The Steppe Mammoth was the largest of the mammoths clearly, and was the largest terrestrial animal since the indricotheruium 20 million years before.


 by DiBgd, Deviant Art user
The Colombian mammoth, Mammothus colombi, had a far more generalized diet-dung indicated that even fruit made up a large component of the diet. This was a successful animal, ranging from Rivas to Medicine Hat and from Los Angeles to Vero Beach. The size rivaled that of its Eurasian counterpart-the largest bulls, once classified into their own species the Imperial Mammoth, would have been slightly larger than Jumbo the elephant (like mammoths, Jubo has become an adjective and synonymous with the gigantic).  Unlike the Steppe mammoth, the Colombian mammoth managed to last long enough to encounter human beings, appearing in rock art in Utah and what first appears to be tapirs in Mesoamerican art may actually be memories of prehistoric elephants.

by Charles Knight
Then there’s the three species of dwarf mammoth, each roughly the size of a small pony.  Like other elephants, mammoths experienced island dwarfism, an evolutionary phenomenon where smaller, less resource-intensive populations of large species are selected and eventually speciate. Mammuthus lamarmorae in Sardinia, Mammuthus exilis in Santa Rosa, and Mammuthus creticus in Crete all evolved independently from giant mainland ancestors before going extinct like all the mammoths.


#3.  Mammut=Mammuthus
Speaking of mammoths, this is one that comes up a great deal. This one is short but has an intriguing history. People tend to use the terms Mastodon and Mammoth interchangeably. I remember in first grade arguing that the Black Power Ranger was driving a mammoth, not a mastodon.  American Mastodons lived alongside Wooly Mammoths in the Northern half of North America and were about the same size, but they diverged in evolution long before. During the Miocene epoch, probiscideans diversified into four branches- the hoe-tusked Deinotheres, long-jawed Gomphotheres, cone-toothed mastodons, and ridge-toothed elephants. 

by Velizar Simeonovski

It’s also not hard to see how they can be confused. They’re shaggy elephant relatives from the Pleistocene, roughly the same size and shape. This is especially difficult since the American Mastodon’s genus is Mammut!

by Charles Knight
In the 1790s, there was an attempt to classify the weird giant bones discovered in Europe and America that looked very much like elephant bones. So, in 1792, Robert Kerr, a Scottish anatomist, looked at specimens brought over from the recently established United States by his fellow fossil enthusiast Thomas Jefferson.  Kerr, agreeing with Jefferson’s slaves, identified the bones as those of a prehistoric elephant, calling it Elephas americanum. However, later that year, Kerr erected a new species since the teeth were far different from Elephas (then containing species of living elephants and mammoths), and called it Mammut for the ancient Siberian underground monster. Apparently, Jefferson was fond of the name Mammoth, and wanted to use it for the American “elephant”, so he might have had some influence on Kerr’s reclassification. In 1817, however, Cuvier ignored Kerr’s name and dubbed the animal Mastodon.  
 by Charles Knight

While Cuvier’s name became popular in media and the popular culture, Brookes acknowledged his colleague Kerr’s name and called the new genus of mammoths Mammuthus instead of Mammut.  There’s also the fact that Jefferson considered the Mammut and the Mammuthus to be the same animal, arguing that the teeth Cuvier described were from his carnivorous Megalonyx (described based on giant claws, and later turning out to be a ground sloth). I think everyone would prefer Cuvier’s name, but unfortunately the rules of nomenclature are a cruel mistress (I will devote another post on this) and Mammut is the name we’re stuck with. Like Brontosaurus, Mastodon is relegated as the common name rather than the scientific one.
  
#2 Oviraptor=Citipati,
Ah, Oviraptor. One of the most misunderstood dinosaurs, but endlessly popular.  Would you believe it’s based on one, crushed specimen?  When the legendary Roy Chapman Andrews went on his famous expedition to Mongolia, he found a nest full of dinosaur eggs and a small theropod on top of the nest.  Andrews had found many nests and eggs earlier in the expedition, belonging to Protoceratops, so he assumed the nest belonged to Protoceratops and the theropod was raiding the nest. His supervisor back in New York, Henry Fairfield Osborn, dubbed it Oviraptor, and saw the long arms and powerful beak and assumed it to be a specialist egg-thief.  The toothless beak also reminded him of Struthiomimus, and so he classified it as an Ornithomimid. So, early  depictions of Oviraptor show it as an Ornithomimid. 



 by Rudolph Zallinger
The Cold War closed off further contact between American paleontologist and Mongolia until the 1990s, when Mark Norell led another American Museum team to Andrew’s old sites. This time, he and his Mongolian partner Rinchen Barsbold found many more oviraptorid fossils, including one very large oviraptor lying over another nest, this one containing embryos and eggs of its own species. The news rocked the paleontological world. Oviraptor was cast from egg-snatcher to loving mother.  Oviraptor was now well-known, well-established, and had a new look-Big Mama (as she would be called) had a tall crest and her brooding position suggested at least partial plumage.  

 by Luis Rey
In 2001, however, they found the skull of new oviraptor species, Citipati. Big Mama was reclassified as this genus. However, in those 10 years, Oviraptor had become set in its way, stuck in the form of Citipati. Indeed, without the Citipati specimens, Oviraptor is reduced back to only being known from Andrew’s specimen. However, Citipati has given us a very good luck at Oviraptor’s body type, as have other oviraptorid specimens. Like Velociraptor and Dromeosaurus, which were poorly known until Dromeosaurus was discovered, Oviraptor’s enigma has been solved after decades of confusion.
  

#1 Megalosaurus=Becklespinax, Valdoraptor and Neovenator
With Britain being on top of the world at the time dinosaurs were first discovered, it’s no wonder the first two dinosaurs found were British: The ornithopod Iguanodon and the theropod Megalosaurus. The legendary anatomist Richard Owen named them dinosaurs. While William Buckland’s first Megalosaurus was found in Jurassic rock, Owen assigned more English theropod fossils to the genus, extending the temporal range from the early Jurassic to the early Cretaceous. 
 
by Édouard Riou
Even before this, the two animals were paired together in the minds of the public. There was the giant herbivore, there was the giant predator. Naturally, they would be connected to each other. Poor Hylaeosaurus made up the third member of Owen’s dinosaur triumvirate, but has always been a background animal.  It was Iguanodon and Megalosaurus that were the stars of Benjamin Waterhouse Hawkins’ prehistoric sculptures of Crystal Palace, and are still a rail ride away through the London boroughs.
by Benjamin Hawkins
Iguanodon’s reconstruction was based partially on an iguana, and likewise the Megalosaurus was based partially on a monitor lizard. These animals were the original slurpasaurus, and were pictured in mortal combat a full century before filmmakers dressed up iguanas and monitors as dinosaurs. Just looking at these old images by Eduard Riou and John Martin seems like a flashback to dinosaur movies of the 1940s

by John Martin
Even as time went on, the duo continued. Indeed, if you were to read any comprehensive dinosaur book, they shared many continents in the Early Cretaceous, and Megalosaurus first originated in the early Jurassic. Even in the Dinosaur Renaissance, the two were inseparable, arising together whenever early dinosaur discoveries or early Cretaceous Europe came into the discussion.  In their own way, they came together like Apatosaurus and Allosaurus and Tyrannosaurus and Triceratops.

 by Bernard Long
This was because of an unfortunate habit in the 20th and19th centuries. You see, every specimen closely resembling a well-known or established species was thrown in. Between 30 and 40 species were named between 1826 and 2006, and all but one turned out to be either a very different theropod, or too poor to get any data. Iguanodon also received this treatment, but the span was geographical, not temporal, and so is not important in this case.

 artist uncredited
Instead, we should focus on specimens that were assigned to Megalosaurus from the early Cretaceous of Europe. First, let’s look at the dinosaurs from the Hastings Beds, the oldest part of the Wealden supergroup. 3 vertebra were found in 1856, all having long spines. At first, they were considered to belong to Buckland’s Megalosaurus, and so Owen instructed Hawkins to give the Crystal Palace Megalosaurus a tall hump. However, they were assigned to a new species in 1884 and then to a new genus Altispinax in 1923 along with a theropod tooth. The tooth turned out to be non-diagnostic, however, and so the theropod spines were assigned a fourth species Becklespinax, tentatively placed as a carnosaur  Megalosaurus woodwardi is a tooth taxon, which are dubious and difficult to classify. Megalosaurus superbus’ original specimens were lost in the battle for France in World War 2. Tarsals (foot bones) from 1858 was assigned to Megalosaurus oweni in 1889. Finally, George Olshevsky in 1991 assigned it to a new genus, Valdoraptor.   Fittingly enough, the Iguanodon remains in the Hastings beds are also either dubious teeth or split into two new genera of Iguanodonts-the robust Barilum and the gracile Hypselospinus.  Darren Naish, an authority on the Wealden’s dinosaurs, talked about the theropod enigma’s in a post on Tetrapod Zoology http://scienceblogs.com/tetrapodzoology/2007/10/02/becklespinax-and-valdoraptor/
 
So, what was the main predator of Iguanodon, found in the Wealden proper? It was thought to be Megalosaurus when it was discovered in 1978, and many teeth found in the area were assigned to Megalosaurus. However, in 1996, Steve Hutt, Dave Martill and Mike Barker identified it as a new genus related to Allosaurus called Neovenator salerii. I hope to feature this species in a blog by itself, but in the meantime, I’ll just say that it was a carnosaur, not a Megalosaurus. So, whenever you see a large theropod hunting Iguanodon in a book or film, it is Neovenator, not Megalosaurus.

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