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Re: Dinosaur Revolution Review



----- Original Message -----

> From: Anthony Docimo <keenir@hotmail.com>
> To: augustoharo@gmail.com; ron.orenstein@rogers.com
> Cc: mickey_mortimer111@msn.com; dinosaur@usc.edu
> Sent: Tuesday, 13 September 2011 6:03 PM
> Subject: RE: Dinosaur Revolution Review
> 
> 
> two replies in one.
> 
> 
> 
>>  Date: Tue, 13 Sep 2011 07:29:22 -0400
>>  Subject: Re: Dinosaur Revolution Review
>> 
>>  Excuse my ignorance, but when was the evidence of parental care in 
> hadrosaurs (which I thought was based on evidence that the young remained in 
> the 
> nest for some time?) refuted?
> 
> No idea...maybe people realized it was anthromorphic to assume nonhumans care 
> for their young?

+++++++++++++++++++++++++++++++++++++++++++++

Geist and Jones (1996) called into question the arguments for altriciality in 
hadrosaurs. The authors pointed out that Horner's evidence for altriciality 
(poor epiphyseal ossification) was more likely to be a taphonomic artifact than 
an ontogenetic status. They compared altricial and precocial birds and did not 
find any difference in epiphyseal ossification between taxa. Rather, the 
authors found a difference in ossification of the pelvic girdle between these 
two neonatal types. Using this new criteria the authors went back and look at 
_Maiasaura_ and _Orodromeus_ nestlings and found that their pelvic development 
was more similar to precocial birds and crocodylians than to altricial 
passerines. 

Carpenter covers this as well in Eggs Nests and Baby Dinosaurs.

Jason

Refs:

Carpenter, K. 1999. Eggs Nests and Baby Dinosaurs: A Look at Dinosaur 
Reproduction. IUP. Bloomington, IN. pps 216-219

Geist, N.R., Jones, T. 1996. Juvenile Skeletal Structure and the Reproductive 
Habits of Dinosaurs. Science. Vol.272(5262):712-714