Natural Selection (Evolution)

by xeno6696 , Sonoran Desert, Saturday, August 06, 2011, 16:29 (4668 days ago) @ dhw

dhw,-I guess I misinterpreted your desire... if you don&apos;t care to have direct quotes...-When Darwin wrote his book, he had no access even to the contemporary work done by Gregory Mendel, which demonstrated the actual mechanism of change-->genetics. Genetics became molecular biology, in which the central dogma is DNA-->RNA-->protein. -When we got knowledge that change was propagated down through the DNA, natural selection was expanded by the addition of DNA. When we gained knowledge that cells can modify their own DNA, this added into the model as well. -The short version is that modern biology as I experienced it, doesn&apos;t accept that organisms simply undergo a process of passively waiting for mutations as I understood the original Darwin theory. To the extent that a creature is evolve-able it engages actively with its environment. Natural selection cannot happen without a selection event; Natural selection decides which organisms live, and ultimately THAT decision is what provides fodder for future rounds of evolution. So... Natural Selection isn&apos;t JUST what gets left behind, you NEED to look at the entire process, and I think that&apos;s why I was taught Natural Selection as the ENTIRE process, and not the pared-down version I see you and David using. -The version of evolution that I see David attacking in his book is Darwin unchanged; NOT the version I learned in school which combined several different mechanisms for genetic change. -As for Beta-Lactamase:-&quot;In other words, how does random change constitute a response?&quot;-In the case of Hall&apos;s experiment, it wasn&apos;t a response. The change that resulted in gaining a function of beta lactamase came about by frame-shifts over generations. The key point from Miller is precisely that raw natural selection could result in something novel--something both yourself and David have previously rejected. The fact that it happened at LEAST once... means that the statement that nothing new can be created by classic Darwinian selection is false.-&quot;In that case, what was the environmental pressure to which the bacterium responded? Either this was a random mutation or it was a response to the environment, but you seem to be trying to have it both ways, which makes no sense to me.&quot;-The pressure didn&apos;t occur until some of the bacteria first gained the ability to process Lactose again: suddenly able to process lactose, their population exploded while those that could not process lactose remained about the same. In this case there was no extinction because the population that couldn&apos;t process lactose wasn&apos;t in competition with the population that could. But in accordance with the accepted scientific definition of evolution, &quot;A change in the frequency of Alleles from generation to generation,&quot; we just witnessed an evolution event. If you don&apos;t accept that definition, I can at least tell you that it exists in two textbooks I remember from undergrad, as well as in professional writings from Pigliucci and Miller. ->You have argued in any case that you see &quot;no reason at all to assert that Natural Selection isn&apos;t enough.&quot; Even if we were to accept your definition, it is clear that NS is far from enough. It does not explain innovations such as sex, flight, sight (i.e. totally new organs, which I would associate with macro-evolution), it excludes random mutations (according to my interpretation of &quot;random&quot;), and as it is worded, it doesn&apos;t even indicate any kind of change, let alone the all-important factor of survival, without which the organism&apos;s response will be of very little use!<-I don&apos;t see where NS as I understand it excludes random phenomenon at all...-Here&apos;s the issue; Evolution by NS explains by my estimation about 70% of biological phenomenon. At present there is not an existing theory that matches it; and if we&apos;re to operate under methodological materialism, THERE IS NO OTHER THEORY. (right now) Methodological materialism is essentially the idea that scientists don&apos;t invoke the supernatural in their theories, relying upon a general assumption that AT BEST we can&apos;t tell the difference between the natural and supernatural. The best theory at present doesn&apos;t have to explain everything, it has to explain more than any other theory. I&apos;m ignorant of current views of how organs evolved, so I can&apos;t really defend anything there. -But I accept (again) the theory as it sits right now, and I await for the story to expand&#226;&#128;&#148;or maybe even replaced&#226;&#128;&#148;I&apos;m not particularly attached to NS beyond the aforementioned &quot;better than the alternatives.&quot;

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\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"