Re: Theory of Non-Avian Dino Extinction

[Joe Daniel <jdaniel@aristotle.net>]

Paul Willis wrote (edited):
> 
> Hibernation may not be triggered by temperature changes. Decreasing photic
> periods may be as important (if not more so) in triggering the onset of
> hibernation. Consider it this way: Why do animals hybernate? Because,
> during winter at higher latitudes, food resources are rarer and so by
> slowing down the animal places less demands on its body for food. Why is
> food more scarce in winter? Because the decreased photic period reduces
> plant growth. 

According to my ecology profs, you can also add water supply to
hibernation pressures.  Many animals, particularly insects, in lotic
systems enter a diapause during the height of summer if the stream they
are in begins to dry up.  I believe the tropical mammals that have been
found to hibernate also pick the dry season to hibernate although I am
not sure about this.  Course, the food resource idea Dr. Willis
mentioned is most likely the driving force here, too.  Just different
environmental effects causing it.

Joe Daniel