[lbo-talk] Altruism & Evolution?

[ravi]

Miles Jackson wrote:
> On Mon, 29 Nov 2004, Luke Weiger wrote:
> 
>>If altruistic behavior wasn't at least occasionally in the "interest" of our
>>genes at some point in the past, we wouldn't see any altruistic behavior.
>>That much we should all be able to agree on, and if we can't, some of us
>>must not understand evolution.
> 
> I gotta spank Luke on this one: this is naive sociobiology.  Not even
> Darwin argues that all traits in a species are inevitably the result
> of natural selection!  Check out Gould's spandrel analogy (discussed
> at some length in The Structure of Evolutionary Theory).  It is
> absolutely incorrect to assume that all behaviors observed in
> humans today must have occasionally contributed to reproductive
> success at some point in human history.
>

while i agree with you (and the importance of gould's point), at least
for reasons of parsimony, it seems that many biologists do seek to
understand current behaviours and traits in terms of selection
pressures. the thing with altruism is: a) it is not just some odd
behavioural trait but directly relates to fitness, and b) it *decreases*
the fitness of an individual. point (b) is IIRC wilson/sober's
definition of altruism: behaviour of an individual that decreases its
fitness relative to another individual or group.

given the significance of altruism as a trait, i think it is important
to demonstrate either that a) it did not evolve in response to selection
pressures (or is a side effect of other traits that did) or b) it can be
reconciled with the model (perhaps genotype propagation) in some way:
wilson/sober, for instance, use a group selection model to demonstrate
the feasibility of altruistic traits and their continued occurence.

of course we have to be wary of the reductionist tendency of defining
away altruism.

	--ravi