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Natural Selection? Or Natural Adaptation?

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This isn’t a point I would push too far, but the more I read and keep up with experimental evidence, the more I question the existence of NS. In the ID camp, most would readily accept NS, which is exactly the position I took for a long time. After all, we would admit to ‘microevolution’. But there just seems to be a lot of evidence suggesting that the interplay of genetics and the environment is much more fluid and vital than previously thought.

The following experimental findings suggest to me, at least, that in the case of Drosphila obscura DNA inversions are completely non-random, and connected directly to environmental changes.

Populations of fruit flies on three separate continents have independently evolved identical gene changes within just two decades, apparently to cope with global warming.

“What we’re showing is that global warming is leaving its imprint on genes,” says Raymond Huey at the University of Washington in Seattle, US, who made the discovery with colleagues. “For this to happen in such a short time-frame in so many parts of the world is rather disturbing,” he says.

Here’s the link to NewScientist.

http://www.newscientist.com/article/dn9896-genealtered-flies-testify-to-global-warming.html

(I’m having problem inserting the link. Sorry)

You can also find it on PhysOrg.com.

The article points out that the degree of ‘inversion’ found in these strains is proportional to the average temperature. Well, then, how can this possible be “random mutation”. In fact, the correlation is so strong, that they use the change in the amount of inversion to make a statement about global warming. So, we now have to strike from the Darwinist formula, RM+NS, the RM part. That leaves NS. Yet there is, according to the authors, a direct connection between an environmental stimulus, average temperature, and the amount of inversion. So the question has to be asked: Is NS ‘selecting’ for these inversions, or are the inversions directly linked to the environment and completely independent of NS? It strikes me that the latter half of the question fits better with the data they’ve accumulated. That means we’re dealing with neither RM nor NS, but are simply seeing nature adapt in an almost pre-programmed way; hence, Natural Adaptation. What think ye?

Comments
jerry: The response you gave would be the expected way of looking at things. And, as I stated in the post, I saw things that way up until the last year or so. Part of my reason for posting this is to simply open up the idea, a bit, of there being another explanation other than RM+NS. It seems to me that the simplest explanation here would be that mieotic events (which involves inversion) in the germ line are affected by the temperature: the warmer the temperature, the greater the amount of inversion. Then there doesn't have to be any 'selection' going on. It's just an automatic adjustment that the germ line (genome) makes. This is, as I say, the simplest mechanism, involving neither random effects, nor the selection of said effects. Compare this experiment with that of the Galapagos finches. The beak size of those finches varies over about a twenty year period (the same amount considered in this fly experiment), depending on the amount of rain that falls--which, in turn, affects the amount and size of available seeds. The argument in this paper is that this 'evolution' happened so quickly because the flies reproduce so quickly and copiously. But that isn't true of the Galapagos finches. And, yet, we see the same kind of interplay between environment and morphology. I think it would be very easy to test this hypothesis. In the case of the flies, trap flies that are located at a higher (cooler) latitude, bring them to the lab, have them reproduce (interbreed) at a higher temperature, and then test for the amount of inversion. If the amount of inversion is directly related to temperature (and not RM+NS), then there should be an immediately detectable shift in the amount of inversion. Seems to me that this is very doable. But, without further experimentation, these two alternative realities would, externally, look to be the same thing. Is it time to ask different questions? That's all I'm wondering. Nevertheless, the fact that the same effect is seen on different continents and is so highly gradated seems to me to suggest that it is the environment that is directing all of this; which, again, calls NS into question. Maybe NS is nothing but a bogeyman.PaV
September 1, 2006
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Pav -- I no biologist but I did a bit of research on natural selection (just look at the Wikipedia article for a start) and it seems that environmental factors definitely constitute variables that can impact natural selection.John Singleton
September 1, 2006
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Dr. John Sanford noted the same thing in his book, Genetic Entropy. He quotes Kimura (a Darwinist) who notes that, of all the factors that contribute to who survives and reproduces, natural selection contributes only about 0.4% (yes, that's 0.004). The rest is "noise" that dwarfs any NS process. As Sanford noted in his book, the formal refutation of Darwinism lies in population genetics (i.e. good to bad mutation ratio, environment signal to noise ratio, Haldane's dilemma, etc.), not arguing over the abstracts of whether Darwinism is possible in theory.Ryan
September 1, 2006
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jerry: One of the basic tenets of NDE is that geographically isolated species will diverge to take their own evolutionary paths, sometimes to develop into dramatically different organisms. The strange thing here is that all three groups of regionally isolated fruit flies had the same genetic changes, with such regularity that the change can be observed to move north because of a warming climate. If the changes were truly random, there should be three different adaptations for the three different regions. Thus, there must be some type of specific mechanism at work that is systematically affecting the genomes of the flies. This means there might be some sort of system of genetic change that we're only beginning to comprehend (if I'm not mistaken, similar mechanisms are looking more likely in the way that microorganisms adapt to new demands). Such a system might provide for a great deal of variability within a class of related organisms, but not to bring about unlimited change. So what do those you who believe that random mutation is the means of genetic variation think about this astonishing regularity in the fruit flies climate adaptation? I'd be very interested to hear.motthew
September 1, 2006
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Pav, Why is this not natural selection. The inversion was already there so I am not sure if any change to the genome took place other than through reproduction. If the gene difference causes a benefit at higher temperatures, then basic genetics would predict that this group will do better and thus produce more offspring and then genetic drift will cause higher frequency rates for this allele. Classic microevolution. Let me know if this basic analysis is wrong. I am certainly not an expert on genetics.jerry
September 1, 2006
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Is it instead possible that the human factor in global warming (unnatural amounts of CO2 from industrial sources) is contributing an intelligent component to the fitness function natural selection is applying to the flies' mutations? This would explain the tendency for the adaptation to be inexplicably targeted by multiple populations, since only a intelligently designed fitness should be capable of causing a seemingly designed adaptation, right? This is the same logic applied by scordova to explain the ability of Dave Thomas' "supposedly" non-targeted genetic algorithm to solve an a complex problem better than a human mind. In my understanding, he suggested that the intelligence needed to apply the "shortest path" test negated the lack of a specified target. Since it requires intelligence to pump out industrial amounts of CO2, the selection of those inversions by their intelligently modified environment must be an example of intelligent design, or not?curtrozeboom
September 1, 2006
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(Longtime reader of UD, first comment.) I read an article about this myself earlier today, and it was as if there were a large sign with flashing lights on it proclaiming "DIRECTED ADAPTATION!" But in the article all they could talk about was an example of "rapid evolution." A systematic change in genetics does not sound anything like random variation to me. Wouldn't separate populations adapt in different ways to the environmental changes if it were truly random? If an ID researcher began working on this, it could be an important step toward understanding a deeper genetic mechanism that directs the ways in which organisms change to meet the demands of changed or a new environment. Far from being a research dead end, because "Goddidit," ID could here prove itself to be a leader in an area of research that randomness theorists would only balk at.motthew
September 1, 2006
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