From: ljones@utkvx1.utk.edu (Jones, Leslie Lamont)
Subject: RE: Sexual Selection
News-Software: VAX/VMS VNEWS 1.41    
Organization: University of Tennessee Computing Center
Date: Wed, 9 Sep 1992 19:49:00 GMT

In article 3479 szabo@techbook.com (Nick Szabo) writes

>>In article <28AUG199212530422@utkvx4.utk.edu> ljones@utkvx4.utk.edu
>>(Jones, Leslie Lamont) writes:

>>     I think the advantage of sexually-selected characters are better
>>described by the "sexy son" theory. In this model, females are attracted
>>to certain males because they are hardwired to find the males attractive.
>>Instances of hardwiring have been discovered, as in the case of sword-
>>tailed fish which S.J. Gould discussed in his column a few years ago.
>>    The advantage for the female is that she will bear some sons
>>who will be sexy, reproduce, and spread her genes, including those genes
>>which find those particular male characters sexy. It then becomes a case of
>>runaway selection, with females producing sexy sons and daughters who find
>>the sons sexy (thought there is no implied incest; the lines can propogate
>>separately with distant cousins mating.)

>Both this and the kerosene-drinker explanation seem incomplete. Where did
>these two adaptations originate, and how could they spread?
>How did the female get "hardwired" in the first place?  Why would her
>sons prosper, if the only plumage lovers are mother and daughters, and
>there is no incest?  How is it that both plumage-loving and plumage, two
>completely different kinds of structures, arise at the same time?  What
>is the probability that they would ever be genetically linked?


     Most of your objections are based on a fundamental misusnderstanding. 
You assume that the female who is senstitive to this stimulus (I'll call her 
the horny female from now on) is rare. In reality, most of the females are
horny, the evidence for which is in paragraphs 4-6.
     Therefore, there is no problem of horny females and sexy males arising
at the same time (the females were already there) or with incest (there are 
plenty of other females' daughters out there for her sons to mate with.)
     Here is a fine piece of evidence that horny females are already present
in a  population: In the study of sword-tailed fish which Gould cited, the
researcher found that females preferred males with longer tails. The 
researcher then performed an intriguing experiment. She surgically implanted
sword tails in a species which is closely-related species which does not have
sword tails. 
     Result: females preferred males of their own species with sword tails to
males of their own species without sword tails.
     Conclusion: The females of that species are horny, are hardwired to find
sword tails sexy. The males of that species, however, have yet to evolve to
take advantage of this hardwiring. When a male does, watch out! He'll 
have to beat them away with a stick.
          The females are hardwired in the sense that their sensory/neural
systems 
respond to certain stimuli without prior exposure to that stimuli. This is not 
an adaptation, but a preadaptation. The hardwiring is simply a happenstance
result of the species' sensory system. (Sort of like funnybones. Funnybones, as
far as I know, have no a
a happenstance result of our anatomy. 

--
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Leslie Lamont Jones             ^^       Wildness is our tonic...             
 ljones@utkvx.utk.edu          ^^       We can nnever have enough of nature.
AOL: LeslieJonz                  ^^       -Thoreau             
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Organization: Doctoral student, English, Carnegie Mellon, Pittsburgh, PA