Here’s something interesting to chew on. According to a new study, the greatest thing before sliced bread may have been sliced meat, at least when talking about the evolution of the human brain. Researchers have determined that the development of stone tools used to cut up raw meat meant humans spent less time chewing and more time doing, not to mention thinking,
Harvard evolutionary biologist Katie Zink authored the study published in Nature. While it’s accepted that cutting up food changed chewing and resulted in humans developing smaller jaw, smaller teeth and smaller intestines, no one had measured it. Zink and her team recruited 34 volunteers to chew food (nice work if you can get it). They started with uncut raw goat meat and vegetables, moved to cut-up foods and then to cooked foods. Electrodes attached to jaws measured chewing force. The volunteers spit out the food (raw goat meat – wouldn’t you?) so it could be seen how well it was ground up
The researchers found that moving from raw and uncut to cut up and cooked reduced the amount of chewing and energy expended while chewing by 20 percent. To put that in numbers you can understand, that’s 2 million fewer chews per year. That explains the evolutionary decrease in the size of jaws and teeth and the development of speech. When you realize that chimpanzees spend most of their day chewing, it’s no wonder they never had time to learn to talk.
That reduction in chewing effort also allowed more and better foods to be eaten, especially calorie-dense meats. Those calories fed the ever-growing human brain, which eventually thought up new ways to process foods, leading to today’s ever-growing human belly.
Wait, that last part isn’t in the report – just an observation while walking through the local grocery store filled with boxes and containers of heavily processed foods, along with machines for making no-chew smoothies. Are we reversing evolution by eliminating chewing from our lives?
Chew on that while I try to find a study that needs a volunteer who likes to eat.