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Re: Syntarsus clarification(?)



Jonathan Wagner wrote:

 > Each one seems to have a different shape and/or color
 > (ornithologists, forgive me my rash generalizations), and, if I'm
 > not mistaken, similar species have dissimilar display structures.  I
 > wouldn't be surprised if the likelihood of a similar structure
 > *increases* with genetic distance (since Mr. Crow isn't going to be
 > confusing Geraldine Robin for his wife anyway, if you get my drift).

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.

Note, there are often taxonomic "biases" in the type and general
structure of display devices.  Thus antelope use horns with spiral
ridges, and grouse have bellows.

Thus the issue of how to interpret display structures phylogenetically
is quite difficult, and requires considerable care.

swf@elsegundoca.ncr.com         sarima@ix.netcom.com

The peace of God be with you.