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Re: feathered ornithopods?



Tim Williams wrote:
> 
> The only 'special adaptations' in the anatomy that might be correlated with
> prolonged cold or dark are: (1) insulative body covering and (2) larger eyes
> (e.g. _Leallynasaura_ - though I'm open to the opinion that its big orbits
> are a juvenile feature).

Except you also have the enlarged optic lobes in the Leaellynasaura
endocast. Plus, studies in bone growth indicate that Victorian hypsies
lacked LAGS (lines of arrested growth), indicating they may have
remained active during the winter. These animals were almost certainly
too small to migrate great distances (and would have had to swim ocean
barriers to do so in most cases). The bones of the theropod Timimus show
quite clear LAGs, suggesting it may have hybernated for the winter (or
at least fasted - I wonder if fasting while incubating a nest would last
long enough to cause LAGs?)

This reasearch prompted Peter Trusler to paint a picture showing Timimus
(as an ornithomimosaur) hybernating under a fallen log, with three
Qantassaurs active in the background beneath an auroral polar sky. See:

http://www.adm.monash.edu.au/pa/photoline/dinos.html

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