Via Boing Boing, an article about abortion. Mark Frauenfelder calls it bizarre, but it makes some sense if you think about it. It brings to mind something that I was thinking about the other week. I have been a bit concerned that the human species has pretty much eliminated evolution as a force that is operating on us. Medical science has made it possible for many people to live to child bearing age who in the past may not have made it. In consequence human beings are not being selected for physical fitness to survive at nearly the rate that they were in the past. I started thinking about the ways that we are being selected.

The book The Selfish Gene by Richard Dawkins makes a good case that evolution has selected for altruism. His case hinges on the idea that natural selection occurs at the level of the gene, and not at the level of the organism. So a person who is willing to sacrifice some of his own resources to help his children survive may be making his own survival less likely, but his genes are more likely to be passed on. As I was thinking about this it occurred to me that when a woman has an abortion she is selecting for her own interest and against her own genes. So, over the course of time abortion is a selecting for altruism.

Which also raises the point that over the long term the tendency to have an abortion is also being selected against. If abortion were freely available and had low social and economic costs this would maximize the effect on the population. People who felt that there was nothing wrong with abortion wouldn't have as many children. Assuming there is a genetic component to someone being willing to have an abortion that trait would be selected against.