Re: exogamy, kinship, and heterozygosity

Shannon Adams (
Thu, 03 Oct 1996 15:55:30 -0700

Gerold Firl wrote:
> In article <52uo9m$>, (Robert Snower) writes:
> |> (Gerold Firl) wrote:

> But lets get back to culture and kinship. You pointed out that
> inbreeding promotes kin selection and altruism, which then facilitates
> the development of social/cultural systems based on higher levels of
> cooperation. That creates a mutually reinforcing selection pressure
> in favor of inbreeding. But just as in the biological case, there is a
> balancing pressure in the other direction favoring exogamy, both from
> the biological realm and the cultural: exogamy produces not only more
> physically vigorous individuals, but also promotes political alliances
> with neighbors. This latter factor has been somewhat overemphasized by
> many anthropologists, who choose to highlight artifact and symbol at
> the expense of a more balanced view which would also weigh the issues
> of survival and adaptation, both cultural and biological.

One point I need to make first is that what you term "exogamy" means
different things itself. Cross-cousin marriage is "exogamous" in
relationship to the kin groups of a society. BUT cross-cousin marriage in
"endogamous" in that the two come from the SAME CULTURE/SOCIETY. In fact if
you really think about it the gene pool in non-western cultures/societies in
remarkably small. When non-western peoples practice exogamy weren't not
talking about pulling someone from another state<U.S.>. We're talking about
pulling someone from another village (most-likely a village that alreay
contains some genetic relations even though those relations may not be
expressed culturally) With this in mind I think it is understandable that
anthropologists have "overemphasized" the political alliances because, truth
be known, the person is probably marrying a genetic relative anyway.

> |> Yet the pre-historic human societies found it necessary to solve it
> |> again, with fantastically complicated, extensive systems. Why?
> Here's a couple of thoughts on that question: first, my earlier
> hypothesis - human kinship systems go *beyond* our instincts to promote
> exogamy to a greater degree than what existed among proto-cultural
> hominids.

Although marriage rules of a given culture do (usually) promote (immediate)
kin group exogamy, overall an endogamous marriage pattern shows itself. If
Barry from kin group A marries his cross-cousin, Susan from kin group B
(common ancestors already)and then Susan's younger brother,kin group B,
marries Barry and Susan's daughter, kin group A (in many cultures this is an
exogamous relationship) can you really argue that exogamous marriage rules
promotes "more physically vigorous individuals" based on a widening gene