Arizona State University scientists studying fossilized anklebones have concluded our early ancestors walked with a rather unsteady gait.
Arizona anthropologist Gary Schwartz, along with fellow anthropologist Dan Gebo of Northern Illinois University-DeKalb, found subtle anatomical differences in the bones as compared with modern anklebones.
Schwartz and Gebo compared anklebones from a variety of early human ancestors and compared them with samples taken from modern humans, chimpanzees and gorillas. The research led them to two significant conclusions:
-- Certain ancestral anklebones thought by some to be "half ape, half human" were found to be much more similar to human bones, confirming the specimens were from obligate bipeds who most likely walked on two feet in a manner similar to how we walk today.
-- Structural differences in some of the anklebones indicate they would have walked a little differently than do modern humans, specifically, an ancestral species commonly referred to as robust australopithecines appear to have been knock-kneed.
Schwartz and Gebo's findings contradict the common wisdom that bipedalism was a rather stable, unwavering trait once it evolved in human ancestors.
The study will be detailed in the April edition of the American Journal of Physical Anthropology.
Copyright 2006 by United Press International
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