Even though we have a soft spot for Dippy (Diplodocus carnegii) here at the Carnegie Museum of Natural History, Tyrannosaurus rex—the “king of the tyrant lizards”—is arguably the most famous dinosaur of all. T. rex was a fearsome theropod that weighed up to 9 tons, had a mouth full of razor-sharp, serrated teeth, and dominated what is now western North America during the Cretaceous period about 68 million years ago. But for all these ferocious credentials, T. rex’s closest living relative may surprise you. Take a moment or two to think about it. I’ll give you a hint, you may have eaten one of these in its nugget form at some point in your life. That’s right, the common chicken (gallus gallus domesticus), a slightly less intimidating animal! Was that your first guess?
Not only do T. rex and other dinosaurs share anatomical characteristics with birds—the wishbone, or furcula, for instance—but scientists in the twenty-first century have found molecular evidence to support the relationship, specifically from collagen proteins extracted from T. rex fossils, proteins that are strikingly similar to those found in modern birds. Scientists have also discovered through expressing the gene for feathers in embryonic alligator skin that feathers are highly modified scales. “It tastes like chicken,” the saying goes. But what does chicken taste like you ask? Perhaps a little like dinosaur.
While T. rex is a part of a fascinating evolutionary web that includes the birds we see today, the history of how T. rex got the name T. rex in the first place is no less fascinating. It all began in 1900, when the famous paleontologist Barnum Brown was quarrying in Wyoming for the American Museum of Natural History. Brown was looking for a triceratops skull to wow patrons back in New York City. Spoiler alert: he did not find the triceratops skull of his dreams. What he did find that autumn in Wyoming were the fossil remains of an enormous carnivore. Brown sent this new discovery back to the American Museum of Natural History where curator of vertebrate paleontology Henry Fairfield Osborn analyzed the unknown specimen, finally naming it Dynamosaurus imperiosus (literally, dynamic imperial lizard)—quite a tongue-twister.
Two years later, in 1902, Barnum Brown found another impressive cache of fossilized carnivore bones, this time in Montana. Osborn believed this second find to be a separate species from the first and called it Tyrannosaurs rex. Osborn published a scientific paper in 1905 officially naming and describing both theropods. However, after spending another year studying the two specimens, he came to the startling conclusion that they were one and the same species! Even legendary scientists have face-palm moments. Convention in the field of paleontology states that in such cases the first name sticks—but, lo and behold, Osborn had mentioned T. rex first in his 1905 paper. So, because of this seemingly small technicality, T. rex is T. rex…and not D. imperiosus. T. rex may be the most famous of the dinosaurs, but to this day it keeps its share surprises, both scientific and historical.
Written by: Nicholas Sauer is a Gallery Experiences Presenter and Natural History Interpreter