Entropy and evolution

PZ fisks the creationist’s old chestnut about evolution violating the 2nd Law of Thermodynamics. The bottom line:

To spell it out, there’s about a trillion times more entropy flux available than is required for evolution. The degree by which earth’s entropy is reduced by the action of evolutionary processes is miniscule relative to the amount that the entropy of the cosmic microwave background is increased.

Of course the creationist’s argument was always stupid (hint: closed system), but it’s nice to quantify the stupidity. And the comments are delightful; for example, Matt Heath:

Exactly! If you read discussions of extra-terrestrial life (say Carl Sagan in Pale Blue Dot) “life” is more or less defined as “that which locally pumps away entropy” (at least if we treat machines as extensions of the life forms that built them). So, for example, if we found a planet with oxygen and methane in the atmosphere, whatever was replenishing them (however odd to us) would be worth of the name “life”.

I really like that definition of life. Concise, measurable.
UPDATE: Jason Rosenhouse has a nice follow-up piece, in which he notes “… that the second law plays only a rhetorical role in creationist argumentation. They are happy to use the language of thermodynamics, but they never do the calculations that would be necessary to make a proper argument.”

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