>Later analyses showed that this doesn't really work; that selfish
> behaviors have strong selective advantage compared to the relatively
> weak effects of group selection. It would be very difficult for an
> altruistic behavior to spread and persist within a group if it caused
> disadvantage to the individuals who possessed it.
> Instead, biologists eventually identified alternative explanations for
> altruistic behavior, in terms of kin selection and similar factors.
> Group selection is now discredited as an evolutionary force.
Agreed (both with your point and it's tenuous relevance to he list - unless
"it's" all CAs and thus all intrinsically related..), but with a qualifier.
Are species is generally just a few millennia (ranging from the present to
10 or 12 thousand years ago depending on what group or region you pick) away
from a nomadic clan ecology. The probability of opportunities to act
"altruistically" towards someone in such an ecology would be skewed towards
that someone being a relation by blood or marriage.
Fast forward to the present where, for a great swath of humanity, Darwinian
natural selection has been turned on it's head. From a strict reproductive
success measure, the "meek" (the poor anyway) have "inherited" the earth
whereas from a resource control aspect the rich hold sway. "Selection" can
be viewed as having all but been neutralized in the west on the former front
in that potential reproductive success is only denied to the most severely
developmentally disabled. But biologically we remain for all practical
purposes identical to those clans people above and to the extent that we are
"hard wired" (EO Wilson vs SJ Gould), we operate in response to the same
"nature" as they. I think Desmond Morris is not far wrong when he muses that
in the 1st and 2nd world (and rapidly the 3rd), our "tribe" now largely
consists of the contents of our (email) address books.
As a evolutionary biologist turned programmer, I have gradually shifted from
the "hard" Wilson camp (Social Biology) towards the "soft" Gould("emergent"
Spandrels) by way of Wolfram: Natural selection tends to modify systems and
structures at the "margins" whereas much of the complexity and organization
of same is the direct result of self-organization only relatively
constrained by selective "pressures" from sources on the same and other
scales of hierarchal adaptation.
Given all the above, then the admittedly rare but real phenomena of
"expensive" (fitness lowering) altruism (as opposed to the "cheap" kind;
aka: the "rich" never give more than they can "afford") may not be
surprising or unexpected.