MACROevolution vs MICROevolution - what is it?

Adding variety for selection to work on isn't necessary for starters, and if a daughter population has already begun it will only interfere, as any gene flow interferes with the formation of a species, which is well known. The addition does not contribute to the formation of a species, it can only interfere.You've never even seen a "successor species," that is pure hypothetical hoohah made up to try to make the idea of continuing addition of genetic diversity seem plausible. It doesn't happen and when it does, where there is resumed gene flow from any source at all, the loss of reproductive isolation or mutations or whatever, it destroys whatever species you already have. Species happen to persist in nature for a long time, you don't see additional genetic diversity coming along to alter them, at least not very often. When you do it's usually the reintroduction of a formerly split off part of the population and it changes the species. What you see more often is further selection events as individuals migrate to new locations and their new gene frequencies bring out new phenotypes which over some generations form a new species while losing genetic diversity. You don't need mutations at any stage and they are destructive at any stage except in a static population.Evolution occurs in specific lineages, the way breeding occurs, in a reproductively isolated small population. It isn't always occurring, it occurs most often in these small populations here and there that separate from a larger population, or even form within the population on occasion. It has to lose genetic diversity so there always is a point that may or may not be reached in a given case where genetic depletion makes further evolution impossible, and if that situation is NOT reached or potentially reached you don't have evolution, you don't have new species. Your mutations contribute nothing to evolution.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

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Adding variety for selection to work on isn't necessary for starters,

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Again you fail to see the obvious. Selection needs variety to work on. If there is no variety there it must be added. And it will be.

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You've never even seen a "successor species," that is pure hypothetical hoohah made up to try to make the idea of continuing addition of genetic diversity seem plausible

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More obvious nonsense. Even you agree that new species may be formed by evolution, and that is certainly not invented to support the obvious fact that mutations occur.

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...so there always is a point that may or may not be reached in a given case where genetic depletion makes further evolution impossible, and if that situation is NOT reached or potentially reached you don't have evolution, you don't have new species.

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More obvious nonsense. Obviously new species have formed without any sign of them reaching "genetic depletion". Obviously microevolution is evolution - and the pocket mice and the peppered moth are examples of microevolution based on the appearance of new variation. And equally obviously it is senseless to say that new variation cannot later become a defining trait of a new species (something that I remind you is based on observing that all - or the vast majority - members of a species have the trait - and something that would be dropped if it were no longer true)So, it IS true that we can have evolution and new species even if mutation is continually providing new variation. It is a clear fact that mutations occur and add new variation - which may be selected. Unless you insist that no new species have ever formed then you must accept - at least if you are honest - that mutation has not prevented it. How can it be any clearer that you are wrong ?

I was responding to your claim that "every gene was heterozygos", not suggesting it myself. I called your claim "a completely unsupported assertion." Animals then were like animals now, and animals now are not completely heterozygous. The animals on the ark were drawn from existing populations, not specially made by God for the ark. If junk DNA had been functional genes then there would have been a great, great many more genes, and they would have been completely different animals. "Made up" would be more accurate. This is also "made up." Mutations add genetic diversity with every new daughter population.--Percy

In these discussions we're hardly ever talking about somatic mutations. Reproduction, and the mutations that occur in germ cells, are essential parts of evolution. We're talking about evolution here.Repeating what you're spurious objection led you to ignore, so just using some ballpark figures, if each individual has 100 mutations, and the probability of a beneficial mutation is 0.000001%, and the population is 1 billion, then there are 1000 beneficial mutations per generation. So when you say: Apparently untrue.Plus beneficial mutations are more likely than previously thought.--Percy

Not recently, but I have done a little reading about the breeding history of dogs. My recollection is that single breeders within their lifetimes were able to bring about substantial changes/improvements in the qualities they were selecting for. 20-50 years seems a reasonable answer.--Percy

I confess to not having a clear picture of the scenario described here, but it bears repeating that mutation has played an exceptionally minor role in the breeding history of dogs. Most of the diverse qualities in dog breeds come from existing variation.--Percy

Based on the assumption that mutations are too rare to compensate for loss of genetic diversity.For which you have no support."Rare" is not necessarily "too rare".

I can't possibly have said any such thing. Where are you getting this from? In Message 424 which is the one you seemed to be answering, I said only that there would have been a lot more genetic diversity or heterozygosity on the ark. Except it isn't my claim. My usual estimate is something like fifty to seventy percent heterozygosity on the ark based on around 7% in humans today, since the formation of new species down the centuries would require the loss of heterozygosity or genetic diversity from population to population.Yes, with functioning genes where there is now junk DNA there would have been a great great many more genes but judging from the fact that human beings lived hundreds of years up to the Flood and the first few centuries after the Flood, I think that probably means greater longevity for animals too, greater strength, better functioning hearing, eyesight, smell, etc. more protections against disease, rather than big differences in morphology or general appearance. I'd guess many more genes per trait, making for much more variation in every trait, including possibly more colors and textures of fur or plumage or that sort of thing, but outright differences in morphology I wouldn't think so. Some variation no doubt but not to the point that the animal wouldn't be recognizable from its fossil. I think the whole animal kingdom as well as human beings have lost an enormous range of abilities given us at the Creation. If that were so you'd never get a new species.ToE wishfulness dies hard.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

There are two goals when helping a species recover from a population bottleneck: 1) Increase the numbers in the population to reduce the threat of extinction and to restore it to healthy maintainable levels; 2) increase the genetic diversity. In the case of the Florida panther there is only the single population in southern Florida. Individuals from other populations cannot be introduced to increase genetic diversity. Gaining beneficial mutations is very unlikely on a human timescale except for species with very, very short generational periods, like bacteria. New varieties can be created by reduced genetic diversity, but not new species. New breeds would still have all the same genes and alleles as the original population and could still breed with them. They could never be a new species.--Percy

And that is also the case with the elephant seal and the cheetah. That's the problem: when genetic diversity is depleted to a great extent there is no way to reintroduce it because interbreeding has become impossible and mutations don't occur at any rate that would help the situation. The seals were able to build up their population which is some protection of course, but cats being more loners don't have that advantage. So we agree, o happy day. That makes no sense. You fail to appreciate how much variety occurs through simple changed gene frequencies as a result of nothing more than the reproductive isolation of a small number of founding individuals. All the variety is potential in the combined genomes of the founders, you do not need mutations. There is no reason whatever that a new species would not be the result of many generations of inbreeding in such a population, even to the point of loss of ability to breed with other populations of the same species.\

I might well have missed something, but I can't think of any possible reason why increasing genetic diversity prevents the formation of new species.

Pretty obviously not. You are claiming that mutations can't happen at a rate fast enough to make up for lost genetic diversity. Pointing out that beneficial mutations are rare is not agreeing with you.Again "rare" does not necessarily mean "too rare". "Too rare" is the foundation of your argument. You've made no attempt to support that assumption.Edited by JonF, : No reason given.

You are moving the goal posts. You are saying that evolution will run out of genetic diversity. Mutations add genetic diversity. That is what you need to address.

We already disproved that claim with the examples of the pocket mice and peppered moth. Both examples involve the emergence of a new trait through mutation.

Please show us how the mutation rate is not sufficient to replenish genetic diversity over thousands of years. You do need mutations to get chimps and humans from a common ancestor.