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Author Topic:   Does Neo-Darwinian evolution require change ?
dwise1
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Joined: 05-02-2006
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Message 78 of 114 (601299)
01-19-2011 6:20 PM
Reply to: Message 77 by RAZD
01-19-2011 5:35 PM


Re: circling around the peak with oscillating lineages
Two rather influential graphics early in my studies were both from the circa-1980 article in either Science or Nature which covered the introduction of Punc Eq -- I have a xerox copy of that article stored away in a box somewhere. One graphic illustrated that highly specialized species that are finely tuned to their environments tend to be very short-lived, going extinct when that environment changes to rapidly for them to adapt, whereas less-specialized species tend to be much longer-lived, being better able to weather changes in their environments as well as a wider range of environmental conditions, such that they would appear in the fossil record as being in stasis.
The other graphic is the one that's more apropos here. It illustrated a period of "rapid" change by a slanted line between two conditions of stasis. Over that line was a long parade of bell curves representing individual generations. Each generation's bell curve overlapped the bell curves of the neighboring generations.
Over the years, I have arrived at the opinion that there really isn't any such thing as actual "evolutionary processes." Rather, evolution is mainly just the end result of life doing what life does, of populations of plants, animals, and protista surviving-or-not and reproducing-or-not. What we describe as evolution and evolutionary processes is our observation of and analysis of the cumulative and aggregate effects of life. Nothing magical about it. And the only way for evolution to violate the laws of thermodynamics would be if life itself were to violate those laws, which it does not. And the only way for evolution to be impossible would if life itself were impossible. Just throwing that out there, in part to see how much fire it will draw.
But I do have one question about these graphing models of the individuals of a population clustering and oscillating about local adaptive peaks. Instead of graphing their genomes about those adaptive peaks, shouldn't we be graphing their phenotypes? Because selection does not directly select for or against the genotypes, but rather for or against the phenotypes that those genotypes would express.
Edited by dwise1, : just throwing that out there, ...

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 Message 77 by RAZD, posted 01-19-2011 5:35 PM RAZD has seen this message but not replied

  
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