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Re: Mammalian success and egg predation,
On Thu, 13 Jun 1996, John Bois wrote:
> > BUT live-bearing is by far not the only difference between mammals and
> > the rest of the world, so this seems to me to be a very weak statement.
> > Any flaw in this line of thinking?
> Yes. It is a critical difference. Listen to John McLaughlin from
> _Synapsida_ (he's actually talking about escape from egg-laying for
> mammals--but I believe it applies to all egg layers): "Eggs are highly
> fragile objects, the most vulnerable interval in an egg-layer's life style."
Being as I am quoted here, I want to clarify: I think that eggs were the
most vulnerable interval particularly in the life-cycle of tiny
ground-dwelling vertebrates like early mammals that likely nourished
their young with milk. For dinosaurs, while eggs may have been
vulnerable, I rather doubt that the parents put up with overmuch guff in
the egg-stealing department. I think that the long dominion and sheer
variety of dinosaurian evolution suggests that dinosaurs early worked out
any problems they may have had with eggs, and that anything that mucked
about with their eggs was a fair candidate for leaving fewer genes in the
John C. McLoughlin