"This goes back to Darwin''s The Descent of Man," said Campbell Rolian, a scientist from the University of Calgary in Canada who led the study.The connexion gets stronger.
"Charles Darwin was among the first to consider the relationship between stone tool technology and bipedalism," he said.
"His idea was that they were separate events and they happened sequentially - that bipedalism freed the hand to evolve for other purposes," he added.
"What we showed was that the changes in the hand and foot are similar developments and changes in one would have side-effects manifesting in the other," he explained.
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