Science, Tech, Math › Animals & Nature The Biggest Dinosaur Blunders Share Flipboard Email Print jockermax / Getty Images Animals & Nature Dinosaurs Basics Paleontologists Carnivores Dinosaurs & Birds Herbivores Marine Reptiles Prehistoric Mammals Amphibians Birds Habitat Profiles Mammals Reptiles Wildlife Conservation Insects Marine Life Forestry Evolution View More By Bob Strauss Science Writer B.S., Cornell University Bob Strauss is a science writer and the author of several books, including "The Big Book of What, How and Why" and "A Field Guide to the Dinosaurs of North America." our editorial process Bob Strauss Updated July 03, 2019 Paleontology is like any other science. Experts examine the available evidence, trade ideas, erect tentative theories, and wait to see if those theories stand the test of time (or flurries of criticism from competing experts). Sometimes an idea flourishes and bears fruit; other times it withers on the vine and recedes into the long-forgotten mists of history. Paleontologists don't always get things right the first time, and their worst blunders, misunderstandings, and out-and-out frauds, like dinosaurs themselves, should not be forgotten. 01 of 10 The Stegosaurus With a Brain in its Butt EvaK / Wikimedia Commons / CC BY-SA 2.5 When stegosaurus was discovered in 1877, naturalists weren't used to the idea of elephant-sized lizards equipped with bird-sized brains. That's why in the late 19th century, the famous American paleontologist Othniel C. Marsh broached the idea of a second brain in Stegosaurus' hip or rump, which presumably helped to control the rear part of its body. Today, no one believes that Stegosaurus (or any dinosaur) had two brains, but it may well turn out that the cavity in this stegosaur's tail was used to store extra food, in the form of glycogen. 02 of 10 The Brachiosaurus From Beneath the Sea Charles R. Knight / Wikimedia Commons / Public Domain When you discover a dinosaur with a 40-foot neck and a skull with nasal openings on top, it's natural to speculate about what kind of environment it could possibly have lived in. For decades, 19th century paleontologists believed that brachiosaurus spent most of its life underwater, sticking the very top of its head out of the surface to breathe, like a human snorkeler. However, later research proved that sauropods as massive as brachiosaurus would have instantly suffocated in high water pressure, and this genus was relocated to the land, where it properly belonged. 03 of 10 The Elasmosaurus With a Head on its Tail Daniel Eskridge / Getty Images In 1868, one of the longest-running feuds in modern science got off to a rousing start when the American paleontologist Edward Drinker Cope reconstructed an elasmosaurus skeleton with its head on its tail, rather than its neck (to be fair, no one had ever examined such a long-necked marine reptile before). According to legend, this error was quickly pointed out (in a not-very-friendly way) by Marsh, Cope's rival, which became the first shot in what would be known as the late 19th century "Bone Wars." 04 of 10 The Oviraptor That Stole its Own Eggs HombreDHojalata / Wikimedia Commons / CC BY-SA 3.0 When the type fossil of oviraptor was discovered in 1923, its skull lay only four inches away from a clutch of protoceratops eggs, prompting the American paleontologist Henry Osborn to assign this dinosaur's name (Greek for "egg thief"). For years afterward, oviraptor lingered in the popular imagination as a wily, hungry, none-too-nice gobbler of other species' young. The trouble is, it was later demonstrated that those "protoceratops" eggs were really oviraptor eggs after all, and this misunderstood dinosaur was simply guarding its own brood! 05 of 10 The Dino-Chicken Missing Link Wicki58 / Getty Images The National Geographic Society doesn't put its institutional heft behind just any dinosaur find, which is why this august body was embarrassed to discover that the so-called "archaeoraptor" it prominently displayed in 1999 had actually been cobbled together out of two separate fossils. It seems that a Chinese adventurer was eager to supply the long-sought "missing link" between dinosaurs and birds, and fabricated the evidence out of the body of a chicken and the tail of a lizard--which he then said he'd discovered in 125-million-year-old rocks. 06 of 10 The Iguanodon With a Horn on its Snout Biodiversity Heritage Library Iguanodon was one of the first dinosaurs ever to be discovered and named, so it's understandable that the baffled naturalists of the early 19th century were unsure how to piece its bones together. The man who discovered Iguanodon, Gideon Mantell, placed its thumb spike on the end of its snout, like the horn of a reptilian rhinoceros--and it took decades for experts to work out this ornithopod's posture. Iguanodon is now believed to have been mostly quadrupedal, but capable of rearing up on its hind legs when necessary. 07 of 10 The Arboreal Hypsilophodon MWAK / Wikimedia Commons / Public Domain When it was discovered in 1849, the tiny dinosaur hypsilophodon went against the grain of accepted Mesozoic anatomy. This ancient ornithopod was small, sleek, and bipedal, rather than huge, quadrupedal, and lumbering. Unable to process the conflicting data, early paleontologists surmised that Hypsilophodon lived up in trees, like an oversized squirrel. However, in 1974, a detailed study of hypsilophodon's body plan demonstrated that it was no more capable of climbing an oak tree than a comparably sized dog. 08 of 10 Hydrarchos, Ruler of the Waves Internet Archive Book Images / Flickr / Public Domain The early 19th century witnessed the "Gold Rush" of paleontology, with biologists, geologists, and plain amateurs stumbling over themselves to unearth the latest spectacular fossils. The culmination of this trend occurred in 1845, when Albert Koch displayed a gigantic marine reptile he named hydrarchos. It had actually been pieced together from the skeletal remains of basilosaurus, a prehistoric whale. By the way, hydrarchos' putative species name, "sillimani," refers not to its misguided perpetrator, but to the 19th century naturalist Benjamin Silliman. 09 of 10 The Plesiosaur Lurking in Loch Ness Héctor Ratia / Flickr / CC BY-NC-ND 2.0 The most famous "photograph" of the Loch Ness Monster shows a reptilian creature with an unusually long neck, and the most famous reptilian creatures with unusually long necks were the marine reptiles known as plesiosaurs, which went extinct 65 million years ago years ago. Today, some cryptozoologists (and lots of pseudoscientists) continue to believe that a gigantic plesiosaur lives in Loch Ness, even though no one has ever been able to produce convincing proof for the existence of this multi-ton behemoth. 10 of 10 Dinosaur Killing Caterpillars avideus / Getty Images Caterpillars evolved during the late Cretaceous period, shortly before the dinosaurs went extinct. Coincidence, or something more sinister? Scientists were once semi-convinced by the theory that hordes of voracious caterpillars stripped ancient woodlands of their leaves, prompting the starvation of plant-eating dinosaurs (and of the meat-eating dinosaurs that fed on them). Death-by-caterpillar still has its adherents, but today, most experts believe that dinosaurs were done in by a massive meteor impact, which seems more convincing.