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Experimental Evolution in Fruit Flies


Drosophila melanogaster is a model organism for the study of genetics and some laboratory populations have been bred for different life-history traits over the course of 30 years. Professor Michael Rose, of UC Irvine, began breeding flies with accelerated development in 1991 (600 generations ago). Doctoral student Molly Burke compared the experimental flies with a control group on a genome-wide basis. This is significant because it is the first time such a study of a sexually reproducing species has been done. Burke examined specific genes and also obtained “whole-genome resequencing data from Drosophila populations that have undergone 600 generations of laboratory selection for accelerated development.” The results are noteworthy on several counts:

“For decades, most researchers have assumed that sexual species evolve the same way single-cell bacteria do: A genetic mutation sweeps through a population and quickly becomes “fixated” on a particular portion of DNA. But the UCI work shows that when sex is involved, it’s far more complicated. “This research really upends the dominant paradigm about how species evolve,” said ecology and evolutionary biology professor Anthony Long, the primary investigator.”

For more, go here.

PaV: As usual you are heavily right! There is no doubt that many of the classical "examples" of darwinian evolution, such as the famous moths, should now be recognized as environmental adaptations based on already existing functions in the genome, implying no molecular evolution. After all, Darwin lived in a time where nothing was known in detail of the molecular basis of heredity. Today that is no more true (thanks God). So, nobody should accept any more discussions about "evolution" unless credible molecular data are available. gpuccio
This is not surprising at all but the problem is that darwinists have never needed actual evidence...ToE has always been a figment of their imaginations. van
This is from the abstract:
Signatures of selection are qualitatively different than what has been observed in asexual species; in our sexual populations, adaptation is not associated with 'classic' sweeps whereby newly arising, unconditionally advantageous mutations become fixed.
Things are actually worse than these authors realize. In a genome wide study of bacterial cultures that came out about a year ago, they found that cultures that swithced from one sugar-based metabolism to another, never fully "fixated". That is, when they were able to examine the entire population, they discovered that a very small fraction of genomes did not 'switch over'; meaning that the "selective sweep" was not 100%, which Darwinists presume, and of which population geneticists earn a living. IIRC, I posted that experiment and said that this was devastating news for our friends the Darwinists. This is the end of the world for them. Here's a thought experiment: if in 600 generations a beneficial mutation was not "fixed in an enhanced selective environment, then how in the world did the "black" Biston bistuleria---tree moths---in the London area become "white" in less than a hundred generations due to decreased smoke stack emissions? Remember, Haldane's Dilemena says that at least a minimum of 300 generations. Isn't the sensible answer that the genome is capable of responding to the environment? Our friend at Cornell University admits that neo-Darwinism is dead. Well, now we can say that Darwinism is dead. Good riddance. PaV
What is the relevance of either of these two posts to ID? I assume you are posting them because they elucidate or support some aspect of the ID theory? zeroseven
The only surprised ones seem to be the Darwinists. aedgar
My only comment is: why am I not surprised? gpuccio

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