There are some people who believe that humans are no longer evolving, since we've developed civilization and science. When we study the mechanisms of natural selection, we learn how the pressure from predators made us fast runners, and those who had better immune systems were more likely to pass their genes on. But now we have protection in communities and vaccines against disease. While environmental pressures favor certain traits and spur evolution, we haven't moved completely away from the effects of natural selection. The pressures we have today are just different.
For one thing, we now live longer. This is partly due to natural selection, and partly due to medical science. The very absence of the pressure to reproduce at young age, lest we die first, allows us to delay having children. This gives those who experience puberty and menopause at a later age a better shot at producing children who survive and carry on those traits. Yet since survival plays a smaller role in when and how much we reproduce, sexual selection plays a larger role. What people find attractive in each other and how we meet someone to reproduce with will affect what kinds of children will result.
Real Clear Science looks at how human evolution worked in the past, and speculates on how changing conditions will affect the traits that will proliferate in humans of the future. -via Damn Interesting
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