Re: Good mother dinos

[tonyc@foe.co.uk (Tony Canning)]

>> Another piece of evidence for parental care in dinosaurs comes from their
> position in the vertebrate family tree.  Since both crocodilians and birds
> have some amount of parental care (and lizards, turtles, etc., don't), it's
> reasonable to assume that that is the primitive condition for Archosauria.
> 

Maybe.. but many lizards and snakes DO show parental care, not only brooding/
incubation behaviour, but some skinks appear to remain with the mother for some
time after hatching, presumably gaining protection.  Provision of food has not
been observed. If parental care is ecologically adaptive, phylogeny does not
seem a constraint - it has evolved independently in many amphibians and fish 
(and
insects, arachnids, etc etc).

Horner believes the maiasaur hatchlings must have needed food because he 
assumes a
high metabolic rate - he then presents the maternal care as evidence of high 
metabolic
rate - is this a circular piece of reasoning, or am I being unfair here?

Modern reptiles do not need to feed for a month or more after hatching, and can 
even
grow during this period by metabolism of the yolk reserves present at hatching.

I am not denying maiasaur parental care, just querying whether rather a lot has 
been
made of a little bit of intriguing evidence..  is it not possible that they 
remained
within the nest after hatching, with protection but without food provision?

Tony Canning
tonyc@foe.co.uk

*Opinions, mistakes etc all my own*