9/1/98A zebra has its stripes and a giraffe its neck, birds are known by their wings, and a fish by its gills. For humans, it's two feet and a unique locomotion—bipedalism.
A lot of theories try to explain why humans evolved to walk two-legged. Some say that bipedalism let early hominids rise up to see over the savannah grass and check for predators. Others say that having free hands to tend offspring and gather food was the advantage. Herman Pontzer, a biological anthropology major, supports a third idea: Bipedalism may have been the best way to travel.
