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Re: Mei example



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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