In “Poop-Throwing Chimps Provide Hints of Human Origins” (Wired Science, November 29, 2011), Brandon Keim reports,
From brain scans of chimps that threw most often and accurately, Hopkins found heightened development in and connections between the motor cortex, where physical actions are coordinated, and the Broca’s area, which in humans is central to speech production. Better throwing meant more sophisticated, left hemisphere-reliant brains.
“It supports the idea that these areas could have been selected for as a consequence of throwing,” said Hopkins. “If you imagine that throwing started off as left hemisphere-dominant, before the emergence of speech, then speech and language would have co-opted that side of the brain.”
In behavioral tests, true-throwing chimps also proved especially apt in social intelligence and communication. Intriguingly, they fared no better than poor-throwing chimps on physical problem-solving tests, suggesting that throwing behaviors emerged not for hunting, as is commonly assumed, but to interact with peers.
In other words, they were too stupid to get past throwing poop and do something useful.
Do you ever get the feeling that the human evolution folk are stuck in a pile of …