Re: Floating pterosaurs

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

On Mon, Jul 6th, 2009 at 9:38 AM, quailspg@frii.com wrote:

> So... what are the possibilities for pterosaurs actually floating on the
> water's surface, as ducks do? Would their pelage allow it?

That might be difficult to say. Modern aquatic birds tend to spread preening 
oil on their feathers to 
help waterproof them. It's doubtful that preening glands would fossilise very 
well if pterosaurs had 
them (and if you knew where to look for them).

Cormorants however don't use preening oil, and deliberately allow themselves to 
be soaked to the 
skin in order to make themselves less buoyant (as an aid to diving). They have 
to air-dry their 
feathers before being able to take off. Cormorant feathers differ structurally 
from those of other 
aquatic birds. It might be possible to tell whether pterosaur fuzz was 
absorbant or water repellant 
based on it's structure. It might also have been possible for pterosaurs to 
have taken off wet, since 
they used skin membranes instead of feathers. Then again, modern bats don't do 
well when they 
fall into water.


Rijke, A.M. 1968 "The Water Repellency and Feather Structure of Cormorants, 
Phalacrocoracidae" 
J.Exp.Biol 48:185-189
http://jeb.biologists.org/cgi/reprint/48/1/185.pdf

-- 
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Dann Pigdon
GIS / Archaeologist                Australian Dinosaurs
Melbourne, Australia               http://home.alphalink.com.au/~dannj
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