Re: Dinosaur heart found?

[Dinogeorge@aol.com]

In a message dated 4/21/00 2:01:04 AM EST, NJPharris@aol.com writes:

<< I realize this is a dead horse that has been well and truly pulverized in 
the 
 past, but how do we know this?  We don't *know* of any deterministic 
 connection between perfect blood aeration and endothermy, but without any 
 examples of a fully segregated circulatory system in a living ectotherm, we 
 cannot prove that they are unrelated. >>

Horse is quite dead indeed. And dinosaurs share so many key anatomical 
features with living endotherms and are phyletically so close to birds that I 
consider it >extremely< unlikely that dinosaurs didn't have some kind of 
endothermic regime. It is nice to see that heart is four-chambered (assuming 
this is indeed the fossilized heart and not some kind of concretion), which 
is to be expected from phylogenetic bracket. But endothermy won't be >proved< 
until time travel is accomplished and we can chart the body temperature of 
living dinosaurs. Now is not yet the time to go hog wild with claims that 
dinosaur endothermy is >proved<, etc., etc.