Another “two points” scored for ….. The Aquatic Ape Theory.

To investigate whether early hominins were more like modern humans or chimpanzees, DeSilva analyzed the ankle bones in fossils of human ancestors at various times from 1.5 million to 4 million years ago. He discovered that early humans during this span have dorsiflexion ranges similar to those of modern humans, and couldn't have climbed trees in quite the same way as chimps do, if they climbed at all.

"Frankly, I thought I was going to find that early humans would be quite capable, but their ankle morphology was decidedly maladaptive for the kind of climbing I was seeing in chimps," DeSilva told LiveScience. "It kind of reinvented in my mind what they were doing and how they could have survived in an African savannah without the ability to go up in the trees."

Since tree climbing is useful both for foraging food and for hiding from predators, the benefits of walking upright must have been great to make humans give up their ankles more suited for climbing.

(exerted from)
http://www.msnbc.msn.com/id/30198636/

Well "DUH", their ability to walk around in the waters of rivers, lakes shores and tidal areas to forage for food ........... sure was a great benefit for their survival.



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