[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Dinosaur heart found?



In a message dated 4/20/00 3:14:26 PM EST, jhecht@world.std.com writes:

<< The heart shows a single aorta, like birds but unlike the 
 dual aortas of modern crocodiles, consistent with the belief that 
 dinosaurs were active animals. >>

Note: Shape of heart indicates high activity level of animals, but does not 
necessarily indicate whether animals were endo- or ectothermic. High activity 
level follows from perfect blood aeration (and separation of low-pressure 
pulmonary circulation from high-pressure systemic circulation), but 
endothermy (mentioned in other posts) is not necessary for high activity 
level.