for National Geographic News
Prehistoric people were cooperators, not fighters.
That's the new theory proposed in two recent books and at a talk last month during an annual scientific meeting.
The theory is part of a movement to debunk a long-running scientific bias that early humans were warlike.
"It developed from a basic Judeo-Christian ideology of man being inherently evil, aggressive, and a natural killer," said Robert W. Sussman, an anthropologist at Washington University in St. Louis.
"In fact, when you really examine the fossil and living nonhuman primate evidence, that is just not the case."
Agustin Fuentes, a researcher at the University of Notre Dame in Indiana, agrees with Sussman.
"Humanity evolved much more by helping each other rather than by fighting with each other," he said. "We shaped the environment and changed how other organisms interacted with it."
Fuentes and other researchers believe that early humans were a prey species hunted by bear-size hyenas, saber-toothed cats, and many other large carnivores.
Early humans survived while other primate species died out because our ancestors cooperated to alter their surroundings, the researchers say.
This cooperation deflected the risk of predation onto other nearby prey species, which became more vulnerable because early humans weren't as easy to catch.
The researchers presented their theories in February at the American Association for the Advancement of Science annual meeting in St. Louis, Missouri.
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