The newly identified species were older more primitive and much more ape-like than any hominids known before, but already they were bipedal -- certainly the younger one, probably the other as well.

How did humans evolve into the big-brained, bipedal ape that we are today? This article examines the fossil evidence of our 6 million year evolution. Darwin's great insight, and the unifying ...

and subsequent fossil finds of much earlier bipedal hominids have confirmed that conclusion. Bipedalism, it seems, was the first step towards becoming human.