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Re: Nesting with Dinosaurs.



> > Seriously, though, if egg-eating (ovivory?) by mammals was a significant
> > factor in the extinction of dinosaurs, shouldn't the dinos have died out
> > at, like, the end of the Triassic?  If not, why not?
>
> This question assumes as fact something which is clearly not: that mammals
> and birds changed little from the Triassic.

Actually, I hadn't assumed that.  What I had assumed was that:

1) banging two eggs together requires neither special structures nor a great
deal of intelligence, and I see no reason why therians should be so much
better at it than "lower" groups of mammals as to drive entire clades to
extinction.

2) AFAIK Cretaceous neornithines do not appear to be any more specialized for
whacking baby dinosaurs than enantiornithines.

3) if dinosaur extinction was caused by egg-predation by metatherian or
eutherian mammals, then I would expect the extinctions on each continent to be
temporally correlated with the arrival of those mammals.

Now, I am not arguing that placental mammals and neornithine birds are not
more advanced than marsupials and enantiornithines, respectively.  But I do
have a hard time believing that they are so much more advanced that they
precipitated the total extinction of the non-avian Dinosauria, all at once,
with little hint or prevue.  Evolution takes time--why didn't the dinos evolve
some defenses to increasing pressure?

If placentals and neornithines are so good at taking out dinosaur nests and
nestlings, why do ratites survive at all?  You are arguing that placentals and
neornithines could wipe out ALL non-avian dinos in the Cretaceous, but can't
take out a handful of flightless birds that don't cover their nests.

> Irony usually functions to ridicule ridiculous ideas.  The above idea
> seems rather grounded.  If not, why not?

Whoa, hoss.  I meant no offense--just having some fun with the concepts and
introducing some humor into this all-too-serious list.

I'll look forward to your response.

Matt Wedel