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RE: Warm-Blooded debate
>>Some dinosaurs did have sails similar to the pelycosaur Dimetrodon--why
>>should those sails have been used for any different purpose?
>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.
>> 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. >>
I agree that the function of sails would be warming and cooling. I was lead
to believe (maybe I'm wrong) that this would be a 'great' advantage to an
ectothermic animal. If it were such a great advantage, I would think that
sails would be in the majority, not the minority, i.e. sail backed animals
would quickly fill all niches by out-competing and eating all the non-sailed
animals. Are we witnessing evidence that sails are not a 'real' advantage?