Image: Tom Koerner/USFWS
It’s a sunny day in spring, and you’re driving down a highway. You look out your window and you see a herd of pronghorn keeping pace with you. The whole herd is pushing 60, and they don’t even look winded. They’re faster than coyotes, they’re faster than wolves, they’re faster than cougars–by almost 20 miles per hour. So why are pronghorn so fast, particularly since speed comes at the expense of jumping muscles, trapping them at fences? The answer can be found in fossils record. Twenty million years ago, the Great Plains were stalked by “The American Cheetah.” While these 200-pound cats are more closely related to modern cougars, their long legs and powerful chests were shaped like African Cheetahs, leading paleontologists to think that they raced after ancient pronghorns, driving them to the speeds we see today.American Cheetahs went extinct about 12 thousand years ago, around the time humans arrived in North America. So it looks like Pronghorn ultimately won the race. With your WyoBio Minute I am Dan AM.