Re: Okay seriously now (AAT again)
Pat Dooley (email@example.com)
13 Dec 1994 23:00:25 -0500
In article <firstname.lastname@example.org>, email@example.com (Russell Stewart)
>>Most aquatic mammals have reduced hindlegs (pinnipeds); and many have
>>completely lost their hindlegs (whales, porpoises, dolphins). Why the
>>would humans have grown EXTRA LONG hindlegs? Answer: the evolutionary
>>pressures were different. Long legs are a liability in the water.
>Good point. That's one weakness in the theory.
Please stop referring to modern humans when you talk about skeletal
features that evolved since 3.5 mya. The fossil record gives us a better
picture of human ancestors after the proposed aquatic phase. In this
case, Lucy is one of the best reference points.
Lucy, the first nearly complete skeleton of an Australopithecus
afarensis, had feet that were broader and larger than ours,
(35% of leg length instead of 26%). Her gait was described by
Roger Lewin as "not quite as bad as trying to walk on dry land
wearing swimming flippers but in the same direction."
So, the legs were shorter and the feet much larger than today.
If the AA was evoloving towards a fully aquatic existence that
is what one might expect.