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Re: 2nd law of thermodynamics



In a message dated 95-11-09 10:35:51 EST, jpoling@infinet.com (Jeff Poling)
writes:

>>In a message dated 95-11-08 23:42:41 EST, jpoling@infinet.com (Jeff Poling)
>>writes:
>>
>>>   I got into a conversation with a creationist while hawking my wares
>>>tonight.  He stated that the 2nd law of thermodynamics (you can't convert
>>>100% of thermal energy to mechanical; also; that systems go from ordered
to
>>>disordered, or remain the same) proves that evolution cannot happen
without
>>>the hand of god.
>>>
>>>
>>
>>Just tell him that not even god can reverse the second law of
>thermodynamics.
>
>   I don't think that particular argument helps.  If even god can't reverse
>the second law of thermodynamics, then evolution shouldn't happen AT ALL.
>
>   ... wish I could remember more of my gas thermodynamics classes.  I seem
>to recall cases where entropy in certain situations *does* decrease.
>
>

The biggest misconception concerning the laws of thermodynamics is that
evolution somehow "disobeys" them--that life appeared and evolves in
contradiction to these laws. This is utterly incorrect. First of all, the
immense heat energy of the sun drives all life on earth, as well as its
evolution. The increase in solar entropy is gigantic when compared to the
local entropy decreases on earth caused by and/or resulting in organized life
forms. Entropy certainly can decrease locally (e.g., on earth), provided
there is a compensatory increase elsewhere (e.g., on the sun).

Secondly, every organism consumes organized food and expels disorganized
waste--this is the basic way in which the second law operates with respect to
living organisms. Not counting the rare exceptions of anaerobic organisms
living in highly thermal environments, the energy in food ultimately derives
from the sun; it gets there through photosynthesis, which is also a
thermodynamically obedient process.

Thirdly, the idea that evolution itself disobeys thermodynamical laws,
because the evolution of complex organisms from simpler ones seems contrary
to the laws of probability, stems from the idea of "progress" up the
evolutionary ladder (from bacteria to man). Actually, given the proper
initial conditions and enough time, the evolution of life on earth and on any
other similarly endowed planet anywhere in the universe is thermodynamically
inevitable. Given the energy of the sun, the stirring of the oceans by the
tides, the additional energy and organic chemicals provided by cometary
impacts, and, most useful of all, the autocatalytic and selective nature of
many enzyme reactions, the emergence of cellular life follows, as does
"progress" through evolution by natural selection once life emerges. Natural
selection is the key to understanding the inevitability of the evolution of
more complex life forms from the simplest procaryotic cells.

The hard part (the very, very hard part) for biological science is to provide
the exact, step-by-step sequence of chemical reactions that led to life's
appearance--the first procaryotic cells. Practically all the biochemicals in
extant life forms are highly evolved from their original forms, of which they
have thus left us little trace. We still know about only a small fraction of
the molecular species that reside in our cells and bodies, and of those that
we know, we know the exact structures and detailed functions of far fewer.
Until we acquire much more information about the biochemistry of present-day
organisms, we will not be in a good position to say much about how this
biochemistry may have originated. But to attribute the origination of life to
miracles just because we do not yet understand how it took place is wrong.