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Re: CROCODYLOMORPH ENDOTHERMY

In a message dated 96-01-25 03:02:00 EST, pharrinj@PLU.edu (Nicholas J.
Pharris) writes:

>I'm not convinced that an ectotherm would need a four-chambered heart.
>
>

They don't. But four-chambered hearts permitted a higher level of activity
and, by separating the pulmonary from the systemic blood circulation, also
permitted the evolution of long, erect limbs and tall bodies. Details in
Regal & Gans, 1980, article in _A Cold Look at Warm-Blooded Dinosaurs_.
Endothermy came later--much later.