Re: [Re: A question concerning the BCF hypothesis]

[archosaur@usa.net]

Dinogeorge@aol.com wrote:
> In a message dated 2/25/01 2:04:32 PM EST, david.marjanovic@gmx.at writes:
> 
> << I'd say a four-chambered heart looks like a prerequisite for endothermy,
>  doesn't it? >>
> 
> This isn't obvious. Some fish are partially endothermic and they have 
> two-chambered hearts.

+++++++++++++++++++++++++++++++++++++++++

I think that in order to have such a discussion on the matter, we must first
pin down what we mean by endothermy.

For instance, lamniforme sharks, leatherback sea turtles, varanids and many
insect species all display endothermy and/or homeothermy, but, AFAIK, none of
them show the leaky cell type endothermy that is seen in birds and mammals.

Jura

Jurassosaurus's Reptipage: A page devoted to the study of and education on,
the reptilia:

http://reptilis.net

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