Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)

[Dann Pigdon <dannj@alphalink.com.au>]

Quoting don ohmes <d_ohmes@yahoo.com>:

> --- On Sun, 9/28/08, Dann Pigdon <dannj@alphalink.com.au> wrote:
> > I still doubt that finches can really glide at all. As
> > David Marjanovic pointed out, they tend to fold 
> > their wings back and turn themselves into ballistic darts
> > between active flaps. I suppose you can 
> > get away with that sort of rotund body plan if your mass is
> > small enough.
> 
> That is entirely behavioral, as I am sure you are aware. 

But is it 'entirely' behavioural, or is it something imposed on the animal due 
to physiological 
constraints? I suspect that at the scale of a sparrow, keeping the wings out 
while not actively 
beating them might create more drag (slowing the animal's flight) than what 
little uplift is 
achievable would warrant. It may well be more economical to fold the wings back 
entirely between 
beats, in which case passive gliding in finches would be maladaptive.

(Note that I refuse to respond to the ad hominem attacks in the rest of your 
post).

-- 
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Dann Pigdon
GIS / Archaeologist              http://geo_cities.com/dannsdinosaurs
Melbourne, Australia             http://heretichides.soffiles.com
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