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Re: 4-CHAMBERED ECTOTHERM
On Fri, 26 Jan 1996, D.W.Naish wrote:
> > Four-chambered heart first, endothermy later. (Note that no extant
> > endotherms
> > have three-chambered hearts, but one group of extant ectotherms--crocs--has
> > four-chambered hearts.)
> _Heterocephalus glaber_, the naked mole rat, was shown in 1993 to be a truly
> *ectothermic* mammal. It too has a 4-chambered heart.
And it also evolved from endothermic ancestors.
Note: don't even think
about using this to show that ectothermic dinosaurs could have evolved
from endothermic ancestors. No dinosaur was aquatic like a croc, and
certainly no dinosaur (especially a sauropod, for whom the theory has
been most often advanced) lived in a burrow in the tropics!
> DARREN NAISH
Pacific Lutheran University
Tacoma, WA 98447
"If you can't convince them, confuse them." -- Harry S. Truman