Nest size (was RE: Brooding rex? (was Feathers for T. rex))

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Ken Kinman
>
>      Should probably be more careful what you aim your torpedoes at.  I'm
> not saying there are any hard and fast rules.
>      However, raptorial birds like hawks, eagles, and owls, usually have
> clutches of 2-4 eggs.  Many common prey species (like grouse, ducks,
> pheasants, etc.) have larger clutches more like 5-15 eggs (or
> more).  I see
> no reason that trends among early coelurosaurs (predators vs. prey) would
> have been much different (but again there would be exceptions to such
> trends).

Something for consideration:
IF Galloanserae is monophyletic and near the base of Neognathae, the larger
clutch size in grouse, ducks, pheasants, etc. may be symplesiomorphy rather
than ecomorphology (or rather eco-behavior).  That is, the smaller clutch
size of owls, falconiforms (and sea birds and hummers and what have you)
relative to galliforms and anseriforms MIGHT be a synapomorphy of dervied
neognaths.

NOTE: The above is pure speculation.  It would require more work at mapping
out clutch size onto a number of different alternative phylogenies.
Furthermore, I have no idea of the clutch size of tinamous, which might be
useful to know!

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796