Do human beings still evolve?
By Shlomo Maital
Pick up a 2-week-old copy of TIME magazine, and it’s worse than stale, like week-old fish. Pick up a 4-year-old copy of Scientific American, as I did recently, and it’s still fresh as a daisy. In the October 2010 issue, Jonathan Pritchard writes about human evolution. The question is, are humans still evolving, through survival of the fittest, as plants and animals are? The answer is: Yes, but very very slowly.
Pritchard cites a gene that exists in Tibetans, that took 3,000 years to entrench itself. This gene adjusts red blood cell production and helps Tibetans survive and thrive in the low oxygen levels of the Tibetan plateau. But this seems to be an example that disproves the rule. “The classic natural selection scenario in which a single beneficial mutation spreads like wildfire through a population has occurred relatively rarely in humans in the past 60,000 years.”
Want to believe, for instance, that gene implants can give you NBA-tall babies? Studies show that there are over 50 different genes that influence human height. Even if tall people procreated more than short ones, natural selection would take a long time to muster all those genes and spread them.
The bad news? Viruses, like HIV, evolve far far faster than humans do. We stand no chance of having natural selection evolve HIV-immune humans, before the HIV virus itself evolves to counteract such resistance. Vaccines are the only hope.
The good news? There is also ‘social selection’, the competition for survival among different prototypes of social organization. We have America, with its dysfunctional Republican-vs.-Democrat paralyzed government. We have Europe, with its dysfunctional can’t-agree-on-anything ‘unity’; we have Russia, with its corrupt oligarchic dictatorship and a newly born Cold War relic at its head. And so on… They are all in competition. So, out of all this vast variety of dysfunctional social and political systems, one of them will evolve to endure and prevail, and lead the other systems to imitate it?