It’s one of the most mysterious aspects of animal behaviour, one even Charles Darwin struggled with: why would an animal choose to sacrifice itself to help other members of its own species, at the expense of passing down its own genes? It’s a question fundamental to biology because it amounts to an investigation into the evolutionary logic of goodness.
An 81 year-old Harvard biologist - a colossus of the science - has stirred a hornet’s nest, so to speak, by turning his back on biology’s most widely accepted explanation for animal altruism. Called the father of biodiversity, Edward O. Wilson has revised his earlier theories on evolutionary altruism. In so doing he’s come under stinging attack from fellow scientists. “I don’t know what’s gotten into E. O. Wilson,” writes one blogger.
An article Wilson co-authored last August in Nature magazine called ‘The evolution of eusociality’ sees Wilson fundamentally reassessing his thoughts on what might be called ‘altruistic’ behaviour in socially highly-developed species like ants and bees. Among the five dissenting letters the magazine published following the article’s publication - which Richard Dawkins slammed as a disgrace - one letter was signed by no less than 137 scientists. Much is at stake - one journalist reporting on the controversy called it “a high-stakes inquiry into the nature of good”.
The theory most commonly accepted for evolutionary altruism is kin selection theory, where the logic of altruism is, roughly speaking, ‘if I can’t pass on my genes, I can at least act to pass down genes that are very similar to mine’. For example, in a eusocial insect colony, according to Wikipedia, “sterile females act as workers to assist their mother in the production of additional offspring.”
In his article, Wilson opts for another, decidedly less fashionable theory, called group selection. Group selection posits that genes survive according to the benefits they bestow a group, regardless of their kinship - in other words, that social cohesion determines genetic survival. One of Wilson’s two co-authors, Martin Nowak, says their revival of the theory is based on mathematics - and that the maths of kin selection theory just doesn’t add up. He adds its a maths the article’s critics haven’t engaged with.
The implications of the argument stretch beyond biology. Wilson claims group selection applies to humans too. “Human beings have an intense desire to form groups, and they always have,” Wilson recently remarked. “This powerful tendency we have to form groups and then have the groups compete, which is in every aspect of our social behavior … is basically the driving force that caused the origin of human behavior.”