Increasing brain girth

Dr. William Calvin has published books on climate change, evolution and the human brain. I had first stumbled onto his website when I did a search for Scientific American. This was before sciam.com existed and one of the first results was his - he had put an article on his site he had written that had appeared in an issue of the magazine.

One area of speculation that Dr. Calvin has explored is the reason for the rapid increase in brain volume that occurred in early history. His theory is that the act of throwing was a catalyst. He explains that when a person tries to hit a moving target with a thrown object a flurry of calculations are performed by our brains. Additionally, because the window of opportunity is small there is a time requirement involved that implies a rapidity of processing in the brain. The result, the theory goes, is a concomitant increase in neural capability that enables the increasing skill achieved by the early humans.

This is an interesting theory, especially to one who has thrown balls to moving teammates and who almost instinctively estimated the termination point of baseballs struck and fly through the air. Certainly, some cogitation, though not really conscious  must be involved in these skills. That we are capable of these acts does seem to bespeak some cranial abilities that we gained from our ancestors.

A twist to this theory was found as a comment written for one of the doctor's books on amazon. The person writing says that research has shown the real tasks that use brain power are those involving small movements of our fingers, such as playing the piano.

In the few years since Dr. Calvin wrote about throwing, a lot has been learned about how the brain works and about techniques to map brain excitation in response to stimulus and function. This research will lead to more definitive conclusion may be reached about the factors that are responsible for increased brain size, but for now what we have is still interesting.