Re: Insulation does not = "Warm-blooded"

[Dann Pigdon <dannj@alphalink.com.au>]

David Marjanovic wrote:
> 
> AFAIK all endotherms except polar bears have methods for getting rid of
> excess heat.

They actually have several methods. There are the obvious behavioural methods
(lying flat out on the ice), but in temporate climates their fur tends to thin
out, and they reduce the amount of insulating body fat (apparently in the Arctic
the fat can be up to 10 cm thick). There was a documentary on the other night
about the American and Chinese polar bears that have been brought to Australia
with the hope of becoming a breeding pair. They still require chilled swimming
pools (especially during the summer), but it's not like they mope around all day
with heat exhaustion. They can play quite vigorously with each other for
extended periods without having to resort to their chilled pool.

Dinosaur. There, now thw post has at least SOME relevance on the list. :)


-- 
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Dann Pigdon                   Australian Dinosaurs:
GIS Archaeologist           http://dannsdinosaurs.terrashare.com
Melbourne, Australia        http://www.alphalink.com.au/~dannj/
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