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



Quoting don ohmes <d_ohmes@yahoo.com>:

> --- On Sun, 9/28/08, David Marjanovic <david.marjanovic@gmx.at> wrote:
> 
> > > I beg to disagree. I don't think finches can
> > glide, and I've never seen a 
> > > bat doing it (granted, my
> > > experience with bats begins and ends with the
> > grey-headed flying foxes in 
> > > my backyard). I
> > > sincerely doubt that hummingbirds can glide either.
> > 
> > Oops. Bats are famous for not gliding, and I bet
> > hummingbirds can't do it 
> > either -- their wings are seriously tiny; except for the
> > size of the hand, 
> 
> Googling "flying fox, soaring" brings up numerous hits.

Soaring requires an updraft, so it's not really 'classic' gliding. Assisted 
gliding perhaps?

> Also, hummingbirds
> are known to glide at high altitude in the Andes, iirc, and I have observed
> rubythroats gliding as much as 2 or 3 meters.

Keep in mind my experience with hummingbirds is restricted soley to the 
Australian species (of 
which there aren't any).

> It is a safe bet that any flapper vert has the physical capacity to glide
> short distances, even if the behavioral phenotype may not demonstrate it.

It depends on how short a distance you're willing to call 'gliding'. I suppose 
a brick can glide for 
short distances (close to the top of it's ballistic arc that is, where most of 
it's movement is 
horizontal).

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.

-- 
___________________________________________________________________

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