I’ve said 99 percent of beneficial mutations are function compromising. This is due to the fact there are many ways to break something relative to the few ways of making something.
Also, the pan-genome of E. Coli for example shows pressure to:
either lose genes
not acquire them through plasmid exchange
There is a lot of pressure to lose parts of no-immediate use. That is powerful force of adaptation. Some have said only 20% of E. Coli’s genomes are conserved. Here a figure of its pan genome, but it shows what 20% means approximately:
I got the 99% figure regarding function-compromising beneficials from a presentation by Michael Behe to a private group. I didn’t realize perhaps that Behe might officially only suggest 90% in public. If he’s said 99% somewhere publicly, I’d be happy to cite that. The 90% figure was in his response to Lenski’s criticism of Darwin Devolves.
Other’s are welcome to supply what they think the proper figure should be.
If we say, “we don’t know the percent of function-compromising beneficials are”, then one should consider the implications for evolutionary theory if “we don’t know” or even have a good guess as to what this figure is, because this implies “we don’t know” some important features about the evolution of complexity.
Sorry, Sal, but I found that incoherent. There may in fact be selection favoring the loss of useless genes in fast-reproducing species like E. coli, but that has nothing to do with the claim that 99% of advantageous mutations involve loss of function. Nor does the fact that E. coli’s core genome is smaller than its typical genome. If anything, that shows that genes are gained as well as lost, and in fact seem to be in some kind of equilibrium.
The prevalence of loss of function mutations is not relevant, since selection alters the distribution of fixations from the distribution of mutations.
What Behe claimed is less important than whatever support he offered for that claim, none of which you have mentioned.
Looks like another gap for your Designer God to hide in.
I’m going to speculate there is no “one size fits all” value of beneficial mutations which affect previous functions. Every generation of every population in every environmental niche is going to be different. Since evolution works by modifying existing features as long as the overall effect is beneficial it matters not one whit what happens to previous functions. This whole thing is another red herring barfed up by the Creationists to cast false doubts on evolution.
Of the 40 million or so mutations that separate humans and chimps, how many of those are beneficial, and how many of those are “compromising”?
Also, why don’t we see irreducibly complex systems and new beneficial genes arising in these experiments if these organisms are designed? We are told that a supposed designer adds these things to genomes, so why aren’t we see it in these experiments?
Thanks for your response. I’ll have to think upon what you said. Again, profuse apologies for my delay in responding to you. I had to think more carefully about the concerns you raised, and I’ll have to think more on it.
Howard Ochman and others found that to be the case in E. coli and related bacteria at least a decade or so ago. That is, E. coli acquired and lost megabases of chromosomal DNA over some millions of years. There appears to be a large amount of ‘churn’ in many bacterial genomes.
