It may have something to do with all those Brontosaurus burgers everyone's favorite modern stone-age family ate, but when you think of a giant dinosaur with a tiny head and long, swooping tail, the Brontosaurus is probably what you're seeing in your mind.
Well hold on: Scientifically speaking, there's no such thing as a Brontosaurus.
Even if you knew that, you may not know how the fictional dinosaur came to star in the prehistoric landscape of popular imagination for so long.
It dates back 130 years, to a period of early U.S. paleontology known as the Bone Wars, says Matt Lamanna, curator at the Carnegie Museum of Natural History in Pittsburgh.
Othniel Charles Marsh was a professor of paleontology at Yale who made many dinosaur fossil discoveries, including the Apatosaurus — and the fictional Brontosaurus.
The Bone Wars was the name given to a bitter competition between two paleontologists, Yale's O.C. Marsh and Edward Drinker Cope of Philadelphia. Lamanna says their mutual dislike, paired with their scientific ambition, led them to race dinosaur names into publication, each trying to outdo the other.