WASHINGTON — When it comes to fishing tasty termites out of their mounds, wild chimpanzees don't have the right stuff. Most, in fact, are southpaws. A three-year study of 17 wild chimps in Gombe National Park, Tanzania, found that 12 of them used their left hands when using sticks to probe for termites. Four were right-handed and one was listed as ambiguously handed.
"Contrary to previous claims, wild chimpanzees show population-level handedness in tool-use," reported the research team led by William D. Hopkins of the Yerkes National Primate Research Center at Emory University in Atlanta. Population-level handedness indicates a preference for one hand in a large group. Hopkins' findings are reported in Tuesday's issue of Proceedings of the National Academy of Sciences.
The paper also looked at previous studies of chimpanzees and found that others had noted a left-handed preference when using sticks to fish for termites, but there had been reports of a right-handed preference when cracking nuts.
Scientists have long debated whether nonhuman primates exhibit handedness. Because the hands are controlled by opposite sides of the brain, the finding could indicate that this brain division had begun as long as 5 million years ago, prior to the split between humans and chimpanzees.
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