Wednesday, March 14, 2012

The debate over the evolution of altruism.

Jonah Lehrer does a fascinating article in the March 5 issue of The New Yorker titled "Kind and Kind - a fight about the genetics of altruism". He gives the history of that debate starting by describing the work of William Hamilton and his successors, but centers on the contributions of E.O. Wilson. The last few paragraphs of Lehrer's article, which outline Wilson's current views, are a nice summary that I want to pass on here:
Wilson's current explanation for altruism has returned to a hypothesis first proposed by Darwin.. that human generosity might have evolved as an emergent property not of the individual but of the group…While acts of altruism can be costly for the individual, Darwin argued that they helped sustain the colony, which made individuals within the colony more likely to survive.
The idea is know as group selection, and it's an explanation that most evolutionary biologists now dismiss [inserted note: with the exception of David Sloan Wilson, not mentioned by Lehrer, but whose work is referenced in about 6 mindblog posts.], because the advantages of generosity are much less tangible than the benefits of selfishness. A tribe full of nice guys would be easy prey for a cheater, who would quickly spread his genes through the population. But Wilson believes that it may hold the key to understanding altruism. To make his case, he cites recent studies of "cooperating" microbes, plants, and even female lions. In all these studies, many of which have been conducted in the controlled conditions of the lab, clumps of cooperators thrive and replicate, while selfish groups wither and die. In a 2007 paper that he co-authored, he summarizes his new view in three terse sentences: "selfishness beats altruism within groups. Altruistic groups beat selfish groups. Everything else is commentary."
Wilson's larger point is that, to the extent that altruism exists, is isn't an illusion. Instead, goodness might actually be an adaptive trait, allowing more cooperative groups to outcompete their conniving cousins. In a field defined by the cruel logic of natural selection, group selection appears to be the rare hint of virtue, the one biological force pushing back against the obvious advantages of greed and deceit. "I see human nature as hung in the balance between these two extremes," Wilson says. "If our behavior was driven entirely by group selection, then we'd be robotic cooperators, like ants. But, if individual-level selection was the only thing that mattered, then we'd be entirely selfish. What makes us human is that our history has been shaped by both forces. We're stuck in between."

2 comments:

  1. Ste5e9:46 AM

    All healthy organisms tolerate a load of parasites. Like the selfish amongst the altruistic. My concern is that as society homogenises it is harder to be self-policing within our looser communities. What goes around comes around should be what keeps selfish traits down but if social mobility has achieved anything it has been to allow people to move to pastures new.
    On a bigger level I read yesterday that 1% of americans earn 93% of the income. That does not seem like any kind of healthy parasitic load. If the organism is not healthy....

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  2. Ste5e,

    Your insight through "parasite load" has illumination beyond some obvious "poster language." I think what Reagan did was take what may have been merely on the scale of this parasite load (the small% that abused the system) and made that loom large.

    While we were looking at this nominal load presented by this smallest scale end of society, the opposite end were able to remove something of an exponentially larger scale.

    This concept brings perspective, though the language effect is hard to contain.

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