RE: Warm-Blooded debate

[brucet@mindspring.com (bruce thompson)]

>bruce wrote:
>
>>Some dinosaurs did have sails similar to the pelycosaur Dimetrodon--why
>>should those sails have been used for any different purpose?
>
>>bruce
>
>This idea of sails always struck me as a strange suggestion (use for
>warming).  I mean of over 800 dinosaur genera, on three (correct me if I'm
>wrong) had any semblance of a sail.  If the sail were so necessary, as
>warming for an ectotherm, why didn't a higher percentage of dinosaurs have
>them.  I don't think 'warming' is a valid argument.
>
>Steve

        If the sails were indeed used for heat transfer, they would
function to _lose_ heat as well as gain it.  In a worldwide subtropical
climate, not every beast would need to evolve such a structure.  Of course,
that can be said about any adaptive feature--that not everything that _can_
evolve _does_ evolve.

bruce



        "Dammit, Philbert; what kind of a lepidopterist are you?  For god's 
sake,
man; stand up to them!"