The pronghorn, also known as the American antelope, is built for speed. It has shock-absorbing toes, hollow hair, thirteen 'gears' (gaits, i.e. leg movement patterns), and takes huge gulping breaths to fuel its push. The pronghorn is the Maserati of even-toed ungulates.
The cheetah can manage short bursts of up to 112 km per hour, but that doesn’t last more than a hundred metres before it has to slow down. Over longer distances its speed is more like 64 km per hour, and the pronghorn has that beat: it can go 88 km per hour for close to a kilometre, or 56 km per hour for 6 km.
Why does it need to be so fast? The cheetah has to be fast to catch its prey, but the pronghorn is a vegetarian, and there are no predators in North America that are anywhere near as speedy. One hypothesis is that there used to be predators fast enough to catch it – the extinct American Cheetah (Miracinonyx trumani) is a good candidate – so the pronghorn evolved to outrun them. And now that the American Cheetah is gone, they’re left to speed on their own.
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