good mother dinos and tooth wear

[tonyf@ucmp1.Berkeley.EDU (Tony Fiorillo)]

Tom Holtz reports that
Dave Unwin (U. of
Bristol, UK) at the 1993 SVP.  He showed that, based on embryo-to-egg ratio
found in modern birds and reptiles, the Maiasaura "hatchlings" are actually
the proper size for a late-stage non-hatched embryo.
I don't have Horner's papers in front of me, but I remember that the hatchlings
were reported at one time to have slight wear marks on their teeth. That
would be a minor miracle if they had not hatched yet. I suspect that no
matter what birds do, or reptiles do today, or what Dave Unwin thinks, these
hatchlings were indeed real hatchlings.

Richard Cowen
++++++++++++++++++
In fact in a recent paper by Currie and Horner in Dinosaur Eggs and Babies
(Carpenter et al. eds.) the Hypacrosaurus embryos in the eggs found showed
wear on their teeth.  There is no question that these individuals are still
in the eggs.

Cheers,

Tony Fiorillo
Museum of Paleontology
University of California
Berkeley, CA 94720
tonyf@ucmp1.berkeley.edu