Evolution of Altruism

In a recent issue of PNAS (Just a moment...), Francisco Ayala lays out his view of morality as an exaptation, a new use for a faculty that evolved for another reason. He believes that humans alone evolved, through natural selection, a capacity for moral behavior. Specifically, they evolved high intelligence, which facilitated tool use. Once intelligence reached a certain level, it was coopted by moral behavior. From that point on, cultural evolution takes over. Ayala believes that moral codes evolve by a process of cultural group selection. The groups with the fittest moral codes outcompeted other groups.Ayala’s hypothesis seems to depend on his assertion that morality is unique to humans. He dismisses research suggesting that incipient morality exists in non-human primates. I don’t know how valid this dismissal is. (Unfortunately the research on non-human primates appears to be in some turmoil because of the Marc Hauser affair.)Ayala dismisses natural group selection because it is vulnerable to cheaters. I think his concept of cultural group selection is open to the same sort of criticism.

Are you saying that altruism has evloved as a result of group selection? If so, could you elaborate on how altruism could become fixed in a population despite the existence of non-altruists?Edited by Stephen Push, : Corrected typos.Edited by Stephen Push, : Corrected typo.

Thank you for the link to the article, RAZD.I had been using the term "group selection" to refer to genetic evolution. The article you cited shows how group selection could foster cooperation through cultural evolution, but the authors noted that this would not be the case for genetic evolution. Nevertheless, the authors wrote, "It should be noted, however, that the genetic evolution of moral emotions might be favored by ordinary natural selection in social environments shaped by cultural group selection."

The following quote is from an article in the current issue of Nature: Samir Okasha, Samir.Okasha@bristol.ac.uk
Journal name: Nature
Volume: 467
Pages: 653—655
Date published: 07 October 2010
DOI: doi:10.1038/467653a
Published online 06 October 2010

Good post, Omnivorous.If genes for motor neurons and empathy provide essential advantages such as social bonding and language acquisition, perhaps a certain amount of self-sacrifice comes with the package, even if self-sacrifice itself is not being selected.

Hi, barbara. Even though moral decisions are made in the present, our capacity for moral behavior must have evolved.In fact, I think we also evolved certain drives and biases that push us toward selecting some choices rather than others. For example, most people say they would throw a switch that kills one innocent person to save five, but they wouldn't push one person off a bridge to obtain the same result. That suggests an innate disinclination to enage in up-close-and-personal violence.