biocultural evolution

Rob Quinlan (C611417@MIZZOU1.MISSOURI.EDU)
Sun, 24 Sep 1995 12:50:47 CDT

Thank you, Dave Rindos, for your comments on cultural selectionism.
Unfortunately, I'm still not satisfied with your "black box"
approach to cultural processes. So, I'd like to make a couple
of comments in that direction. Forgive me if I sound polemical.
My intent is not to be argumentative, but to explore some of the
particulars of the gene-culture analogy.

In his last post Dave Rindos said:

>In the posting referred here I was attempting (perhaps less than
>successfully) to make a rather simple point: we do not need either a
>material coding mechanism, nor a fully developed theory for the neural
>coding (or whatever) of culture to apply a selectionist theory to the
>explanation of change. The double helix, and all that, did NOT change in
>any fundamental manner the way in which Darwinian evolutionary ecology
>(for example) had been done. And interestingly, Darwin was able to
>develop his basic theory not only in ignorance of the underlying coding
>mechaism, but with a fundamentally incorrect model for inheritance.

>Hence, by referring to the UNimportance of coming up with the cultural
>analogues for genes, alleles, chromosomes, etc, and by stressing the very
>real complexities of even that system of coding information, I was merely
>attempting to make the point that, for now, we can do perfectly good
>trans-generational studies without worrying about the details at that
>particular level of analysis.

The fact that the population genetic models of the New Synthesizers did
not require knowledge of codons, and the double-helix, is beside the point.
What they did know (reasonably well) were the principles of inheritance
and the criteria of adaptations. For cultural selectionist models to be
evolutionary they too must address the process of inheritance and the
selection criteria for cultural traits. That means they have to
address intra-individual processes (social learning, goal formulation,
etc.) and patterns of interpersonal relations to understand the
principles by which cultural traits are selected and replicated.

>Treating the details of what is occuring inside the heads of individuals
>during teaching and learning [enculturation in the largest of senses]
>therefore can become a "black box" for the purposes of our analyses.
>Again, I can't see where this should cause any real problems.

I disagree. The selection criteria are the product of individual
psyches operating in the interest of the organism, which ought to
result in the differential replication of cultural traits.

>Under the Sociobiological Model, feedback from selection is directed
>towards the GENETIC coding system. Hence, cultural and biological
>evolution are one and the same in that the EFFECT of selection in each
>leads to the SAME RESULT -- CHANGES IN ALLELIC FREQUENCIES.

Sociobiology (in its various guises -- behavioral ecology, evolutionary
psychology, etc.) may be useful to cultural selectionist analyses, because
it specifically addresses questions of the evolution of mechanisms likely
important for the acquisition and replication of cultural traits.
Evolutionary ecology further provides us with a discussion the levels at
which selection is most potent and what that means for the functional
organization of individuals and groups.

>Cultural Selectionism TOTALLY REPUDIATES the Sociobiological assumption.
>Instead, it holds that the focus of selection for cultural behavior is
>100% INDEPENDENT of the genetic coding system; that any amount of cultural
>change can occur without making ANY DIFFERENCE IN THE GENETICS OF THE
>POPULATIONS INVOLVED (again, setting aside in this context the matter of
>the evolution of the CAPACITY for culture in early humans, but I believe
>this should cause no confusion). Hence, to return to an earlier
>statement, the focus of cutural selectionist explanation is CULTURE.

The change in frequency of genes and cultural traits may not covary,
but they are not independent. Cultural traits are selected in the
environment of human minds functionally organized by natural selection.
Therefore, individual and group interests in reproductive fitness should
influence the frequency of cultural traits. It shouldn't be radical
to suggest that expressions of culture vary according to social
context. Nor is it earthshaking to think that we enter into different
social environments with different sets of goals in mind. If our
goals are, in any way, tied to our genetic interests, then cultural
expressions should also be tied to genetic interests.

An analysis of parasitic "memes" may well demonstrate some of the
points I'm trying to make. I wish someone would take this issue up.

Well, this has gone on long enough. But first, one last comment. There
seems to be the beginings of a move toward an integrated approach
to cultural evolution. Boyd & Richerson (1992 In _Evolutionary
Ecology & Human Behavior_) have made an attempt to approach the
issue of social learning in a way that is probably more palatable
for sociobiologists (if not closer to reality). Lee Cronk, coming
from the other side of the issue, has just published a paper
that makes some headway in bridging the gap between cultural
selectionists and behavioral ecologists (see _Ethology & Socio-
biology_ May 1995). Finally, Sperber has a chapter in _Mapping
the Mind_ (1994) which (among other things) examines the meeting
ground between evolutionary psychology and cultural selectionism.
Perhaps we're seeing the beginning of a New Synthesis in evolutionary
anthropology.

Rob Quinlan
c611417@mizzou1.missouri.edu