Inclusive takes on inclusive fitness flap. Fight notes.

A week ago, evo biologist heavyweight E.O. Wilson and others published a paper in which they challenged the standard explanation for why animals do nice things for one another. Nice behavior is a big deal, so the paper raised a big flap.

Let’s say you want to read just two things about this paper. Though my own survey has been less the exhaustive, I feel safe in recommending Zimmer and Hawks.

Zimmer lays it out nicely for the uninitiated, starting with a typically lucid intro:

Why are worker ants sterile? Why do birds sometimes help their parents raise more chicks, instead of having chicks of their own? Why do bacteria explode with toxins to kill rival colonies? In 1964, the British biologist William Hamilton published a landmark paper to answer these kinds of questions. Sometimes, he argued, helping your relatives can spread your genes faster than having children of your own.

For the past 46 years, biologists have used Dr. Hamilton’s theory to make sense of how animal societies evolve. They’ve even applied it to the evolution of our own species. But in the latest issue of the journal Nature, a team of prominent evolutionary biologists at Harvard try to demolish the theory.

The scientists argue that studies on animals since Dr. Hamilton’s day have failed to support it. The scientists write that a close look at the underlying math reveals that Dr. Hamilton’s theory is superfluous. “It’s precisely like an ancient epicycle in the solar system,” said Martin Nowak, a co-author of the paper with Edward O. Wilson and Corina Tarnita. “The world is much simpler without it.”

Now let’s say you want to know why so many other evo people find this objectionable. Go to Hawks:

I can’t believe the amount of attention the paper by Martin Nowak, Corina Tarnita and Edward O. Wilson [1] has gotten. It was in last week’s Nature. The basic idea was that the evolution of eusociality in insects could be explained in a different way that the usual explanation, which involves calculating the relatedness of worker insects to their reproductive siblings. Eusociality has been one of the most visible applications of inclusive fitness theory — that is, the observation that the fitness of a gene that alters behavior may be calculated in terms of its effects on the reproduction and survival of relatives. The paper notes that some aspects of eusociality are not well explained in terms of relatedness, and derives an alternative explanation.

The weird part of the paper is the way it describes inclusive fitness as some kind of theoretical afterthought, useful only as an ad hoc explanation for eusocial insects. It contrasts the inclusive fitness concept with “standard natural selection” as if it were possible for organisms to erase the fact that they’re related to each other! And the authors imply that they have fatally damaged the concept of kin selection.

It’s so contrary to evolutionary theory, that I thought maybe I was missing something. But I’ve been spending time on another problem this week and haven’t had time to follow it up.

Fortunately, Jerry Coyne and Richard Dawkins have both given the paper some attention, and written notes and reactions to it. First Coyne (“A misguided attack on kin selection”) reminds us of why kin selection has been such a successful part of “standard” evolutionary theory for the past fifty years. … [and] Richard Dawkins has also posted notes about the paper.

There’s more to come, surely. But if you mainly want to know what it’s all about, these two are a good start.

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