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Re: Syntarsus clarification(?)



Stan Friesen wrote:

> This was, indeed, my reason for saying that a display structure like
> a crest, is of limited value in phylogenetic inference.  They often
> change rapidly in closely related forms for just this reason.

     This is what I meant in my last postiung on the subject that I may 
not have not indicated clearly.  When talking about adaptations that deal 
with simple survival and going about day to day business, analogies seem 
to be fairly common, implying that there are certain designs that just 
work better than others for a particular lifestyle or means of mobility, 
and so are arrived at independantly.  One might be the case of shark/
icthyosaur/dolphin body plans, complete with dorsal fins, and the true wolf 
and tasmanian wolf.  However, what an animal finds sexy can be entirely 
subjective (this might not always the case, some females prefer lareger and 
stronger males who may have a better chance at survival).  Peacock tails, 
for exaple are large and cumbersome, and might actually be seen as a 
possible hinderance to individual survival, but females find them attractive 
anyway, so the males are copelled to have them for genetic, and therefore 
evolutionary survival.  This sort of "anything goes" attitude in display 
aesthetics precludes analogies (or if there are analogies, they are 
coinincidental rather than indicitve of a similar lifestyle), because 
everybody has thier own sense of aesthetics.  

LN Jeff
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