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From Neatorama:
 This psychedelic image of Emperor penguins is not a fancy blacklight
poster (although it would make a good one), but a thermal image taken to
help find out how penguins stay warm in the Antarctic. THe surprising
find was that while the birds generated heat inside like all
warm-blooded animals, a large part of the penguins' outer feathers were
actually colder than the surrounding air! How can this adaptation
possibly help them? The penguins do lose internal
body heat to the surrounding air through thermal radiation, just as our
bodies do on a cold day. Because their bodies (but not surface plumage)
are warmer than the surrounding air, heat gradually radiates outward
over time, moving from a warmer material to a colder one. To maintain
body temperature while losing heat, penguins, like all warm-blooded
animals, rely on the metabolism of food.
The penguins, though,
have an additional strategy. Since their outer plumage is even colder
than the air, the simulation showed that they might gain back a little
of this heat through thermal convection-the transfer of heat via the
movement of a fluid (in this case, the air). As the cold Antarctic air
cycles around their bodies, slightly warmer air comes into contact with
the plumage and donates minute amounts of heat back to the penguins,
then cycles away at a slightly colder temperature.
Read the whole article
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