Monday, September 6, 2010
Technology and Human Evolution
The consensus among paleoanthropologists these days is that our ancestors created the conditions that encouraged our evolution into modern humans. The use of tools encouraged the survival and spread of mutations that promoted hand dexterity over arm strength; cooking allowed the survival and spread of a key mutation that made our jaws weaker, leaving more space for our brains to grow, and also allowed our guts to shrink; now a new theory holds that the invention of the baby sling allowed us to lose our hair. The invention of agriculture has probably caused the process to speed up, as we acquire genes that make adults able to digest cow's milk -- we have at least three different mechanisms for this, evolved in different parts of the world -- to digest alcohol, survive on a mostly grain diet, and resist the many diseases we have caught from out domestic animals. We are, in a real sense, our own creation.