Evolution proceeds by the differential reproduction of genes, so the challenge is to explain the persistence of a trait that, by definition, leads to an increase in the success of another while not increasing the success of oneself. Selfishness should defeat altruism every time, at least at the gene level.
Some confusion arises because biologists do not define altruism by the intentional state of an actor—benevolent feelings are unnecessary—but rather, by its consequences: whether it enhances the fitness (reproductive success) of the beneficiary while reducing that of the altruist. As a result, we can speak quite seriously about possible altruism in lions, bees and even viruses.
Many animals live in social groups and tailor their behavior to maximize their success and that of their relatives within those groups. But it is misleading to describe such individual-level adaptations as having evolved “for the benefit of the group.” Especially absurd is the contention that the very existence of multicellular organisms, including human beings, supports this idea.
The simple reality, however, is that our cells are genetically identical. When a liver cell labors at the unpleasant task of detoxifying blood while leaving all the fun of reproducing to the gonads, that cell isn’t being altruistic at all but rather wholly selfish, since the success of the gonads is biologically indistinguishable from success of the liver cell.
The GLP aggregated and excerpted this blog/article to reflect the diversity of news, opinion and analysis. Read full, original post: Genes Are Selfish; People Are Not