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Re: Why insulation = endothermy

From: GSP1954@aol.com
 > and even
 > insects over 1 gram. (I have read the work on insect energetics,
 > and all flying bugs over 1 g are endotherms. Below 1 g it is not
 > possible to be endothermic no matter what the metabolic rate or
 > insulation are like.)

Well, so much for the furry caterpillars.  Those (or at least the
species I am familiar with) are right around a gram (they are really
remarkably light).

I can certainly accept a feathered bird or dinosaur with a basal
metabolism (and aerobic capacity) just barely above that of reptiles.
Indeed, one should probably *expect* such a stage in the transition
from the reptilian physiology to the modern avian one.  I do not see
how the modern avian body temperatures could be maintained *without*
insulation.  This means that insulation had to evolve prior to acquiring
the full modern metabolism.

swf@elsegundoca.ncr.com         sarima@ix.netcom.com

The peace of God be with you.