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[Phys-L] Crows in IR

From the posting with my added emphasis:

2. Digestion: Crows are omnivores and are known to eat anything. That would
lead to a great variety in energy expended in digesting a particular meal.
That would in turn lead to a great variety in how much heat is given off by
the digestive system and to a need to *efficiently expel heat in the case
of a heavy meal. Black would efficiently and quickly expel the heat.*

4. Warming and Cooling: A crow finds himself cold standing in a tree, then
flies out into the sunlight and quickly becomes warmed, because his *black
coat is also the most efficient heat absorber.* So the crow may have a
survival advantage over other birds and small animals in cold or hot
climates. Said differently, the crow may be occupying a predatory niche.
< < < < <

Just because a crow (or anything) is black in visible light, doesn't mean
it is a blackbody in IR (or UV). I tried to do a net search for an IR photo
of a crow and couldn't quickly find one. If I ever get a chance, maybe I'll
see if I can take one myself on a cool day.

- - - -
John E. Sohl, Ph.D.
WSU Brady Presidential Distinguished Professor of Physics
Weber State University
1415 Edvalson St., Dept 2508
Ogden, UT 84408-2508

Office: TY 326
Office phone: (801) 626-7907
cell: (801) 476-0589