Answer Monday

Uintatherium robustum

“It was a fantastic beast that looked like it was made up for a…Hindu mythology! It was as big as an elephant. It had saber teeth, gigantic fangs, but it was a plant eater, but had horns, six of them in two rows. It was unbelievable.” That’s a description from the paleontologist Bob Bakker, interviewed for the documentary Dinosaur Wars (2011).

But Uintatherium robustum was a mammal—resembling a rhinoceros in size and shape, although with claws instead of hooves—from the Eocene. Why was it in Dinosaur Wars? As Brian Switek relates, the discovery of Uintatherium fueled the notorious feud between the nineteenth-century American paleontologists O. C. Marsh and Edward D. Cope.

Particularly distinctive of the genus, and featured in the Fossil Friday close-up, is the simultaneously flat and concave skull. Congratulations to Dan Coleman, the first commenter to identify the genus (nobody identified the species) from the close-up. (Tip of the flat and concave hat to Steven Newton for taking the photograph.)