Chimps offer glimpse of humans' past

MADISON, Wis., Nov. 12 (UPI) -- Chimpanzees living in a harsh African environment and using stick tools offer scientists new insight into early human behavior, U.S. researchers said.

Researchers found evidence of tool use among chimps living in western Tanzania's Ugalla Forest Reserve to harvest tubers, roots and bulbs, the University of Wisconsin-Madison said in a news release Monday. Their study was published in Proceedings of the National Academy of Sciences.

The finding supports the idea that chimpanzees can be models to understand how the earliest humans lived and acted, said Travis R. Pickering, University of Wisconsin anthropologist.

The multi-university study demonstrates "the understanding and capability to exploit these resources were very likely within the grasp of the first chimp-like hominids," Pickering said. "It was widely believed that it is a uniquely human adaptation to use tools to dig these things up."

A surprise finding, Pickering and other researchers said, was that the chimps ate underground food resources during the rainy season when food is plentiful, not in times of scarcity. That observation, they said, "challenges our current hypotheses about the role of such foods in hominid evolution and may help re-frame the scientific debate."