If I say, “brontosaurus,” I bet a very specific image of a long-necked, long-tailed sauropod comes to mind. It was one of a handful of the dinosaurs we learned about as kids—at least back in my day—along with the tyrannosaurus rex, triceratops, pterodactyl, and stegosaurus. But the brontosaurus, as we knew it, was actually the apatosaurus. Or... was it?
Scientific American will kick us off with an explanation:
The first of the Brontosaurus genus was named in 1879 by famed paleontologist Othniel Charles Marsh. The specimen still stands on display in the Great Hall of Yale’s Peabody Museum of Natural History. In 1903, however, paleontologist Elmer Riggs found that Brontosaurus was apparently the same as the genus Apatosaurus, which Marsh had first described in 1877. In such cases the rules of scientific nomenclature state that the oldest name has priority, dooming Brontosaurus to another extinction.
So if we scientists knew this all the way back in 1903, why did I—a child of the 1980s and 90s—grow up learning about a dinosaur that apparently never existed? Well, it seems that museums were super slow to adjust to the change, and some flat-out disagreed that it should be changed at all. Its image and name lived on in pop culture, being highlighted in Disney’s Fantasia in 1940 and in The Land Before Time in 1988.
Before we knew it, we were adults, and our young children were learning about the apatosaurus, and we were like, “No, no, that’s a brontosaurus, silly!” Luckily, in 2015, another paleontologist decided there actually were enough differences between the two groups of fossils to classify them as separate species. So the brontosaurus did exist. Maybe.