Re: culture as gene-flow regulator: the arunta
Len Piotrowski (lpiotrow@magnus.acs.ohio-state.edu)
Tue, 17 Sep 1996 21:14:13 GMT
In article <51muh4$kve@news.sdd.hp.com> geroldf@sdd.hp.com (Gerold Firl) writes:
>[snip - at least I read your "theory" Firl!]
>This post will put forth a hypothesis about some of the cultural
>adaptations of the australian arunta as they relate to the problem of
>gene-flow regulation in the difficult circumstances of the desert
>outback.
Didn't know there was such a problem. Could it be you just made one up for the
sake of the exercise?
>These ideas were posted here earlier this year, but I thought
>it might be interesting to summarize them again, since there is a vocal
>opposition to the idea of culture as a functional adaptation currently
>active in the newsgroup.
Never saw that proposal before. I have seen considerable doubt, though,
expressed over human social behavior as a result of functional adaptation.
Could that be what your thinking of?
>I'll try to show how a sociobiological
>analysis of arunta kinship and marriage customs leads to falsifiable
>predictions about the arunta lifestyle, which in the scientific
>tradition is the best test for any theory.
It's not the only way to examine a hypothesis, but I get the gist.
>Some salient facts:
>In arunta ideology, conception is divorced from copulation. conception
>is thought to result from the quickening influence of the local totem
>spirit upon the mother. Husbands and wives have sexual relations, but
>marital fidelity is not insisted upon, and at the periodic festivals
>when large groups of the sparsely populated interior congregate, sexual
>licence is encouraged. Arunta men undergo the process of subincision,
>where the penis is slit from root to head through the urethra; semen
>thus is not ejaculated so much as dribbled.
Salient citations?
>Analysis:
>Given the low population density of the australian desert, gene flow
>rates are low; that is, it takes a long time for genes to travel
>throughout the population. This can be a problem; it essentially
>decreases the genetic variety available to cope with environmental
>changes, leading to lower levels of fitness at the population level. I
>propose that the features of arunta culture listed above are functional
>adaptations which increase the velocity of genetic diffusion.
The population density of the Australian desert is low because it can't
support a larger population. Gene flow rates are low (citation?) presumably
because of infrequent contact among distant groups (of Arunta I suppose). This
"salient fact" must be true despite your theory, or else you've got access to
two bodies of data, one before "sexual licence" was encouraged and one after
(who encouraged it by the way - the "sexual licence craving" gene?).
Otherwise, your low gene flow evidence cannot be used to both pose the problem
and then represent the solution. If "sexual licence" ... "increase the
velocity of genetic diffusion" how come your gene flow rates don't already
show increased gene flow?
Where on earth did you get the semen dribble idea?
>Subincision, in this view, would be a method by which the incidence of
>marital impregnation would be minimized.
Evidence and citation please? Otherwise, pure speculation ignoring the
meaningful and ritualistic aspects of the situation.
>Since semen is not ejaculated
>against the cervix, birth control can be achieved very reliably. In
>female-superior positions, fertilization can be easily avoided.
Evidence and citation please? What prevents ejaculation, what suggests the
female-superior position as practice, and what would be different about
sexual practices at macro-band gatherings versus familial band contexts? Would
have to theorize that either ejaculating males copulated more and/or female's
assumed an inferior position at macro-band gatherings, a "salient" fact not
supported by the evidence.
>The idea that children are the offspring of the local totem, rather
>than the biological father, would be a means of minimizing jealousy and
>avoiding sexual competition between men.
A tautology based on negative evidence. There is no jealousy or sexual
competition, so why the need to explain it, let alone account for the lack of
a behavior as a functional adaptation? The entire band is descended from an
ancestor (not necessarily totemic in the strictest sense), including the
biological mothers. So what is suggested in this relation which emphasizes a
male "trait" (jealousy) rather than something else (group cohesion)? The
gathering of the macro-band serves to join the various bands, each with a
separate piece of the overall story of their mythological account for the
world: the Dream Time. Instead of minimizing a non-existent individual
selfishness, the social and ideological arrangement accentuate the positive
effects of group cooperation, maintenance, and solidarity.
>The promiscuous sexual activity at large gatherings would accelerate
>genetic mixing, since matings would occur between individuals who were
>ordinarily more widely separated than typical marriage partners.
Hardly, since marriage partners are chosen from the same gathering. This
vision of sexual promiscuity is belied by the strict division between the
sexes of various ritual ceremonies conducted at these gatherings. Do you have
citations?
>Predictions:
>Large-gathering copulations have a higher incidence of male-superior
>positions, leading to higher fertilization rates.
However, you have no evidence that any of this is true for the Arunta. It
would be quite unusual for sexual position to change from band territories to
macro-band locations. The dribble semen hypothesis (is this verified?) would
hardly be ameliorated by dribbling from above, let alone act as the equivalent
to ejaculation. There is no suggested evidence that higher rates of
fertilization occur at macro-band gatherings, or that they are the result of
"sexual licence." There is no evidence that "sexual licence" even exists. And
there is no comparative evidence linking differences of gene flow in similar
situations with or without macro-band "sexual licence."
Grandiose theories constructed from the imagination which reduce complex social
interactions to the determinants of genes have the ring of scientific validity
but on closer examination are only contortions of unknown and unverified
facts and speculations explicated by reductionist processes that ignore the
holistic and meaningful aspects of what is known about human social behavior.
>Young men on walkabout get laid a lot.
Sorry, I don't see it!
>Summary:
>Complex, abstract, spiritual aspects of human culture are intimately
>related to the problems of physical adaptation, and are amenable to an
>evolutionary analysis. Some of the unusual aspects of arunta culture
>should be expected to appear in other low density cultures, such as the
>eskimos, where the benefits of enhanced rates of gene-flow have been
>found to outweigh the costs of lower paternity-confidence.
I didn't hear mention in this entire story anything about the complex,
abstract, and spiritual aspects of the Arunta, only semen dribble and
purported gene flow problems despite even the current effects of the "sexual
licence" process upon the very data said to be in need of gene flow
enhancement!?
I may be wrong, but I think you will find few who are convinced by this
presentation of sociobiology's methodological salvation for anthropology.
Cheers,
--Lenny__
"If you can't remember what mnemonic means, you've got a problem."
- perlstyle
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