Re: parental care (was Re: RE: Dinosaur Planet, parts 3 & 4 )

["Ken Carpenter" <Kcarpenter@dmns.org>]

Having seen the limbs of the specimens in question, they are significantly 
better developed than a hatchling robin. More like chicken. 

>>> ANN SCHMIDT <ashmidt@flash.net> 12/20/03 21:54 PM >>>
--- Ken Carpenter <Kcarpenter@dmns.org> wrote:
> Here is the problem, just because SOME extant
> vertebrates care for their your is not PROOF that
> dinosaurs did. It is INFERRED that they did because
> some do today. That is the big difference. An
> inference may be very logical but is difficult to
> frame as a testable hypothesis. 
Yet can't it be admitted that not caring for their
young would be highly unusual given how widespread it
is among so many animal groups today?  Land
vertebrates in geenral seem to, not just "some" of
them either.  Except for a very few specialized
species (that still devote a ton of energy to to
enable them to not care for their young), all modern
birds from every group care for their young, all
modern mammals do, all modern crocodilians do (some
more than others) whiel many modern amphibians,
lizards and even snakes do. 

> As for the underdeveloped joints, well I guess
> someone better tell young chickens they can't walk.
> Next time you eat chicken look at the leg joints.
> You'll see that they are poorly formed, especially
> if you get a small, young thigh (KFC seems to have a
> lot of those). Everyone seems to forget that a
> hatchling hadrosaur is very light, a few pounds (kg)
> at most. Cartilage is a very strong substance and
> can easily support the few pounds of a baby.
> Ken
What about the comparisons done that showed the
dinosaur infant bones to correspond to modern birds
whose young can't move much when hatched?  In
comparison to the Troodon embryos which supposedy
compared well to the bones of chickens and other birds
whose young can move about and feed themselves soon
after birth (but are still cared for by their mother).
 I wasn't aware of any research released that
seriously contradicted this.

Jonathan Schmidt