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Re: Brooding over dinos



>Except, perhaps the most obvious one - the very shape of the wing itself.  It
>works so well for flying that (here is my main point) the fact that it is
also
>highly engineered for BROODING has been neglected by modern science.  We have
>all been in the teliological habit of assuming that flight requirements
>dictate the shape of the wing and its feathers.  My point is: the wing is
>HIGHLY evolved for brooding as well -- therefore I ask, on what grounds do we
>assume that flight came first?

I do not assume anything, but I think it is one thing to say that the wing is
useful in brooding and that it is "highly evolved" for it.  in fact the
wing of
living birds has many specific adaptations for flight that have nothing to do
with brooding, but I cannot think of any that reverse this process.  In fact
wings can be used for a variety of functions (eg the canopy-feeding of the
black heron, the "startle" displays of the sunbittern and kagu) in addition to
brooding and flight, but without some specific predictions as to what
anatomical features to look for in each case I do not see how you could tell
whether any (or all) of these functions were involved in their evolution.

>    Also, for future reference, the term brooding DOES include sheltering
>hatchlings.  The most precise term for what a bird does with eggs is
>INCUBATION, which is a sub-category of brooding.

True.
--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
1825 Shady Creek Court                 
Mississauga, Ontario, Canada L5L 3W2          mailto:ornstn@inforamp.net