The Unsung Transverse Arch: The Previously Hidden Key to Human Bipedalism

Watching any four-legged animal run may cause you to wonder whether four legs are more advantageous than our two. Many four-legged animals can far outpace two-legged humans in a sprint—horses, dogs, or of course the world’s fastest animal, the cheetah (who have their medium-sized build to thank for their superior speed). Of course, with a top speed of 27 mph, we’re faster than some quadrupeds, like the elephant (who can reach speeds of 15 mph).

But if we wanted to run, say, 40 miles per hour, we might need another set of legs. Yet few people would give up their bipedal abilities; after all, it’s part of what makes us human and sets us apart from the rest of the animal kingdom.