A Prehistoric Donkey (4-legged hoofed animal) from the southwest or south of the border. Fossilized Remains of it were discovered by archaeologists at or near the La Brea Tar Pits.
On wikipedia. Type in the following key words: "La Brea Tar Pits" Scroll down Until you see a list of all of the prehistoric animals including the "Mexican Ass," that archaeologists found the remains of.
by Aaron Ferber October 13, 2007