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Re: The Right-to-Left Shunt of Crocodilians Serves Digestion (body fat)



Jonas Weselake-George wrote:
> 
> I don't have many lizards in my ecozone but I get the impression that they
> tend to grow larger instead of putting on large amounts of body fat (as many
> mammals do).

The problem with large amounts of subcutaneous body fat (as seen in mammals) is
that it tends to act as an insulator. Insulation is great if you can generate
heat internally and don't want to cool down, but for an animal that relies on
external heat sources it becomes maladaptive (since insulation works both ways;
keeping heat out as well as in).

Some lizard species store fat around the base of the tail, and some accumulate
it as internal 'abdominal fat bodies' (also present in amphibians),  but I
wouldn't expect an extensive blubber-like subcutaneous sheath over the whole
body.


-- 
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Dann Pigdon
GIS / Archaeologist              Http://geo_cities.com/dannsdinosaurs
Melbourne, Australia             http://heretichides.soffiles.com
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