Does Neo-Darwinian evolution require change ?

See previous post since I think it adresses some of what you are saying here. But can change be slowed down that much ? The only force that can potentially work against change and for stasis is selection, and it seems not only that the higher the mutation rate, the higher selection pressures most be to maintain stasis, but also that as JonF said, that in the multi-dimensional landscape of things there are many potential for change, which would turn selection around to work against stasis.

And what % of the genome do you think has a function ? 5% ? 10% ? 30% ?The truth is we don't really know, but this has been an ever increasing number in the past couple of years. I think most geneticists today would say at least 30%, but the ENCODE project has opened the possibility that the entire genome would be functional, and even that some times both sides of the DNA strand is useful, putting it's functionality at over 100%.

Yes, and some plants produce 100 offsprings each generation. And more offsprings does mean mor leverage for natural selection to work on.But it also means a whole boatload of new mutations in the population. It means although the workforce of NS is bigger, the work to be done is also bigger. (all other things equal)This is why the reproduction rate influences the potential for selection, but it is the mutation rate that effects the cost of selection. The higher the rate, the higher the cost, and vice versaThink about it with a small rate. If 1 in 10 individuals inherits a mutation (o,1mpipg) then the cost is low, and selection can easily pay the bill to eliminate the mutation with any normal reproductive rate above 1,1.

What are the mutation rates ? How much selective pressure can the species support ? etc. These are some of the question that you need to answer if you want to analyse the potential of any given species for stasis.Turns out E.Coli has both right answers for it to be able to maintain stasis. It's mutations rate is under 1mpipg and it can withstand enormous selective pressures (you can rebuild the entire population even after having decimated it to a few individuals. genetic meltdown is not an option)

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Since the overall mutation rate is lower than the size of the E. coli genome, on average there won’t be any mistakes made when the cell divides into two daughter cells. That is, the DNA will usually be replicated error free.

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Sandwalk: Mutation Rates

And even so, it does not stop the mutation load from accumulating, since every single individual that would survive would still have inherited multiple mutations. And if high selective pressure breaks down the mutational load, relaxed selective pressures accelerate it. And so, at the end of the day, if you had a population of x individuals, and you finish with x individuals, putting boom and bust cycles in between won't really have changed anything.

Unless you are implying tht mammalian populations can sustain as much intense selective pressures as E.Coli, you'll have to explain to me what this has to do with what you quoted.

But taking Natural selection as that it kills (or totally prevents from reproducing) is taking it at it's most powerful form. Taking it in simply reduced or ehanced reproductive success only makes matters worse. Yes, but even taking those in the population closer, their babies will be farther then there parents because of the high mutation rates. And, even if we take the babies of that generation which are closer then the rest of the other babies, they will still be farther then their parents. etc. etc.I perfectly understand the pendulum effect with small mutation rates. As I said, I can see such things happen in E.Coli population because there mutation rates are under 1mpipg.What I'm saying is, with higher mutation rates, no pendulum effect will happen. The mutations will always force a population to drift away from the optimal peak, and NS will resist this drifting but, even when taking it in it's most powerful form (kill the less fit, only the most fit reproduce) it still cannot stop it. Cost of selection is certainly a very important notion in population genetics.

Ok I think I got misunderstood there. What I was saying was: The % of functioning genome has been ever increasing in the past few years, as I'm sure you know. Right now, anyone can safely say that at least 30% of the genome is functional.What I said concerning ENCODE was simply that it ''opened up the possibility'' that the entire genome had a function. I'm not saying it proved anything, and I certainly know the difference between functional and transcribed.Therefore, all I'm saying is that when seeing how genetics has been unravelling the secrets of previously thought ''junk DNA'', and how more evidence comes to open the possibility that maybe the whole genome is functional, I think it is the idea that any part of the genome is junk that should be regarder with great skepticism, not the other way around.

I hate discussing with you because it is so blatantly obvious that you argue in bad faith. Other evidence, and how they are interpreted, does not erase evidence from other fields of science.If you feel the evidence from other fields show life has been going on for billions of years, then you can't just ''not worry about it'' when seeing that it conflicts with another field. You have to identify what is wrong in that field, were is the missteps. That is what everyone here, except you, is doing. And it is obviously the right approach.

Of course, and the most deletirious mutations will be wiped out of each generation without any problem.But some individuals most survive and reproduce, and what I'm sayign is that the high mutation rates imply that those individuals will have inherited lots of mutations, and although they may have the least deleterious set of mutations to have appeared in that generation, doesn't mean they still don't have those mutations.

But this is statistically very unrealistic. If a generation moved away from the peak by 50 mutations, in a genome of 3 billion, it is extrememly improbable that the next generation will move back towards the peak on not simply farther away.

For example:

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Therefore, more than one third of the mouse and human genomes, previously thought to be non-functional, may play some role in the regulation of gene expression and promotion of genetic diversity.

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Junk DNA Guides Embryo Formation – SciScoop Scitext ChemSpyI think that we are starting to see a paradigm shift in this field. The paradigm was that, DNa was mostly junk, and so it was a waste of time to try searching for it's use. Once more and more parts are being unravelled and found to have a use, I think an avalanche of discoveries in that field will come. But, as prof. John Mattick said:

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the failure to recognise the implications of the non-coding DNA will go down as the biggest mistake in the history of molecular biology

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The most conservative estimate of the deleterious-to-beneficial ratio of mutations was 50 to 1. I've seen some suggest perhaps as high as a million to 1.But even with the 50-1 ratio, it's still pretty obvious that the high mutations rates will push the next generation farther away from the peak then their parents from the optimal peak.

Kimura's ''neutral evolution'' only works if the vast majority of the genome has no function. Even if only 5% of it were functional, a mutation rate of 40mpipg would result in two mutations falling into the functional part of it. And all that I have said would still hold. Of course, this problem becomes increasingly more difficult the more functional the genome turns out to be.

This is about exactly what I was going to say.