Hi again,
Thanks for the responses to my query, particularly Chris for your comments
and facts on feathers, moult etc. The single annual wing moult certainly
seems to preclude any real possibility of varying wing shape for particular
purposes.
However the fact that feathers can be under some form of developmental
control on a seasonal basis, be it at the level of hormonal/cellular or
genetic/transcriptional/translational control, does imply that the
"pre-adaptive setup", if you like, is in place. Also, if body feathers can
moult more than once each year there is presumably not a lot stopping wing
feathers doing the same. I imagine, too, that migratory waders alter
their metabolism and muscle mass to some degree prior to migration,
concomitantly with their extraordinary increase in body weight....
....This is all very much in the realm of "Theoretical evolutionary
possibilities" which is beginning to sound very Lamarckian, but....
Cheers,
Harvey
PS, Chris, I've just begun growing my full beard back, so I'll have to stop
thinking about it at this point.
..........................................
Dr Harvey D. Perkins
Divn Biochemistry & Molecular Biology
Faculty of Science
Australian National University
Canberra, ACT, 0200, Australia
ph:(02) 6249 2663; fax:(02) 6249 0313
email:
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