New research seems to show mordern human evolution is supercharged:
In a study published in the Dec. 10 issue of the Proceedings of the National Academy of Sciences (PNAS), a team led by University of Wisconsin-Madison anthropologist John Hawks estimates that positive selection just in the past 5,000 years alone — around the period of the Stone Age — has occurred at a rate roughly 100 times higher than any other period of human evolution. Many of the new genetic adjustments are occurring around changes in the human diet brought on by the advent of agriculture, and resistance to epidemic diseases that became major killers after the growth of human civilizations.
“In evolutionary terms, cultures that grow slowly are at a disadvantage, but the massive growth of human populations has led to far more genetic mutations,” says Hawks. “And every mutation that is advantageous to people has a chance of being selected and driven toward fixation. What we are catching is an exceptional time.”
The findings may lead to a very broad rethinking of human evolution, Hawks says, especially in the view that modern culture has essentially relaxed the need for physical genetic changes in humans to improve survival. Adds Hawks: “We are more different genetically from people living 5,000 years ago than they were different from Neanderthals.”
Science fiction’s dirty little secret is that it tends to believe in pseudoscience more often than it does in real science; even supposedly “hard” science fiction is littered with impossible or just wrong science. The idea that evolution has “stopped” is one of them, usually used in a setting which contrasts the brave manly colonists of Proycon B with the teeming soulles dependent masses ruled by an incompetent, corrupt bureaucracy of Earth. So much for that idea.