Re: Mei example

[Tim Williams <twilliams_alpha@hotmail.com>]

Jaime Headden wrote:

> As for sleeping, rehashing this a tad: What proof shows me that *Mei*
> was sleeping in this posture, versus hunkering down during a
> volcanoclastic explosion?

I wondered about this too.  Taking forty winks is just one of several 
possibilities.  For example, tucking one's head under one's wing seems to me 
to be an excellent way to avoid getting dust and ash in one's eyes and up 
ones's nose.  Of course, _Mei long_ had bigger problems.  But I think the 
fact that eumaniraptorans exhibited this behavior is less important than the 
reason(s) why they adopted this posture.

> Add to that similar adaptations for tucking the legs and evidence for 
> incipient or latent
> arm-folding mechanisms in decidedly non-flying animals whose direct
> ancestors NOT bearing these features were also flightless, suggests that
> this posture had _nothing_ to do with flight. Maybe it was about leaping
> from trees. Maybe it minimized body surface exposure during brooding or
> hibernation. Maybe it was about being a predator and the need for a "snap"
> reflex to engage prey.

I agree with Jaime.  I think there is strong evidence that the bird-like 
arm-folding mechanism of maniraptorans did NOT evolve specifically for 
flight, but is an exaptation.  I have my own ideas on why this mechanism 
evolved.

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