By Erin Wayman
Ancient rumbles in the jungle might have left a lasting mark on the human hand.
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The hand’s proportions are such that clenching the fingers creates an effective bludgeon, a pair of researchers observes. Perhaps, they propose online December 19 in the Journal of Experimental Biology, evolution played a role in making the hand such a punishing weapon.
But other scientists are skeptical. “There’s no compelling evidence that the hand evolved in this way,” says Mary Marzke, a physical anthropologist at Arizona State University in Tempe. It’s more likely that the ability to throw a good punch was just a lucky (or unlucky) consequence of evolving nimble hands suited to making and using tools.