Suggested in my hypothesis is that life is an energy
moderator (with modification through descent)
"Generally speaking... chemical stress caused by high or low
pH does not require as extensive an adaptational response as
high pressure or temperature."
- Life on the Edge, M. Gross
Too hot or too cold (I call it the Goldilocks syndrome) may
well be the main stress on life. (I think life can be
defined as that which best adapts to that heat cycle)
If so you would expect there to be HEAT shock proteins (see
the lit on that). But we would also expect to see COLD
shock proteins for dealing with the other end of the liquid
water spectrum.
Gross's book gives examples and looks at cases of both heat
and cold shock proteins.
tom