Human Evolution Speeding Up!

The LA Times has a great article on Charles Darwin. There's lots of evidence that human evolution is speeding up, not slowing down:

Until recently, conventional wisdom held that human beings had mastered their environment so thoroughly that the imperative to evolve in many ways diminished about 10,000 years ago, when agriculture gave rise to more-stable societies. "People thought that with technology and culture, there'd be no reason for physical things to make any difference," said Milford Wolpoff, a paleoanthropologist at the University of Michigan. "If you can ride a horse, it doesn't matter if you can run fast." That turned out to be wrong. As it happens, the pace of evolution has been speeding up -- not slowing down -- in the 40,000 years since our ancestors fanned out from Ethiopia to populate the globe. And in the 5,000 to 10,000 years since agriculture triggered the growth of large societies, the pace has accelerated to 100 times historical levels. "When there's more people, there are more mutations," Wolpoff said. "And when there are more mutations, there's more selection."

Here's an interesting example. Increased sex drive = ADD?:

...they found a number of genes involved in brain development, including a version of a dopamine receptor gene called DRD4 that is sweeping through the European population. Some think it is a novelty-seeking variant, others that it affects libido. What they do know is that having two copies increases the odds of having attention-deficit hyperactivity disorder.

Genetic mutations that help prevent malaria and that help adults digest milk, as well as to prevent Type 2 diabetes are other examples of recent human evolution. Blue eyes are a recent development. It was only 6000-10,000 years ago that the first human with blue eyes was born somewhere near the Black Sea. Darwin suggested that the genetic mutation for blue eyes might have made humans more sexually desirable (I'm seeing a theme here), but there is research being done to see if pale skin and light colored eyes gave Northern Europeans an advantage in absorbing more vitamin D in weaker sunlight conditions. Those of you who are blue-eyed and don't "believe in" the scientific fact of evolution might want to look in the mirror and ask yourselves how you got to be such an oddity.