Current human evolution? (Introduction)

by David Turell , Friday, March 27, 2015, 22:02 (3528 days ago)

A discussion by atheist Jerry Coyne:-http://www.washingtonpost.com/opinions/are-humans-now-in-control-of-the-forces-of-evolution/2015/03/27/b538a008-b07d-11e4-827f-93f454140e2b_story.html?wpisrc=nl_popns&wpmm=1-"After my public lectures on evolution, someone in the audience invariably asks this question: “Are we still evolving?” People want to know if humans are getting taller, smarter, better looking or more athletic. My answer is truthful but disappointing: We're almost certainly evolving, but we don't know in what direction or how fast. While some studies show that natural selection is acting on traits such as age of menopause (increasing), age at which first child is produced and blood cholesterol (both decreasing), this is hardly the stuff that excites futurists. And, regardless, there's a critical difference here: Selection isn't the same as evolution. Even if selection culls people with high cholesterol, unless those people are on average genetically different from those with lower cholesterol, we won't see the genetic change over time that constitutes evolution. Human generations are long, evolution is slow, and so all we can say is that there's the potential for evolution. -"We've seen some evolution in our species over the past few millennia, but it was detected by reconstructing history from DNA sequences. For example, we know that during the past 10,000 years, several pastoral populations of humans — those keeping sheep, cows or goats for milk — evolved genes for adult lactose tolerance, gaining the ability to digest dairy products. This trait was useless in our earlier ancestors who, after weaning, never encountered milk. And in the past 3,000 years, Tibetans acquired genetic adaptations that allowed them to thrive in their high-altitude, low-oxygen home. But these well-documented changes are limited to particular populations, so the evidence for recent evolution of our entire species remains scant."