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Re: Bird reduce their "heating bills" in cold climates
On Mon, Jul 5th, 2010 at 2:09 PM, Jura <firstname.lastname@example.org> wrote:
> --- On Sun, 7/4/10, David Marjanovic <email@example.com> wrote:
> > > During the last Friends of
> > Dinosaur Dreaming meeting late last year
> > > it was hinted that Leaellynasaura may have had a
> > hyper- long tail
> > > (the full-scale drawing held up - with the help
> > of several people -
> > > had to be seen to be believed!).
> > This was confirmed at the SVP meeting last year. The length
> > is utterly mind-boggling.
> Neat. I wonder if the tail was used to lure predators away, and/or establish
> a dominance
> hierarchy as in many lizard species.
Just imagine if Leaellynasaura had a bushy fox-like tail covered in
protofeathers. Not only would it
make a handy scarf for wrapping around the body while sleeping (as with arctic
foxes), but by
raising their tail-hackles and swishing that impressive tail about they could
make themselves look
several times larger than they actually were. If the bluff failed and they were
forced to flee, then a
predator might get nothing but a mouthful of tail fuzz for its trouble.
Matthew Herne's SVP abstract says:
"Dorsoventral and cranial expansion of postzygapophyses (up to 44% of vertebral
length) on vertebrae in the terminal half of the tail of L. amicagraphica
alternative to ossified tendons to provide caudal axial rigidity."
In the absence of ossified tendons, would such a postzygapophysis arrangement
allow for flexibility
in the horizontal plane, while stiffening the tail sufficiently in the vertical
plane to keep it off the
ground? If not then the arctic-fox-tail analogy falls flat, since it would take
significant flexibility in
the horizontal plane to wrap the tail about the body.
Spatial Data Analyst Australian Dinosaurs
Melbourne, Australia http://home.alphalink.com.au/~dannj