Wednesday, February 29, 2012

Just another Evolutionist PRATT, the usual paradigm-bound misconception of Speciation

Somebody just started a new thread at EvC titled An example of speciation in action? giving an example of reproductive isolation bringing about changes between two separate populations of a bird called a Blackcap. Differences in appearance between the two are minimal but differences in behavior are enough to keep them apart.

This is treated as some kind of wonderful event, at least a step on the way to macroevolution, which makes it just another evolutionist PRATT (Point Refuted a Thousand Times). I for one have answered it over and over both at EvC and on my blog, and I can't be the only one.

All this is merely one of the ways variation naturally occurs in species because of built-in genetic variability. It's nothing more than normal "microevolution," changes that are expected because of this built-in genetic variability, which can come about through anything that isolates a portion of a population from another so that they don't interbreed. Genetic drift within populations even does this but populations may also become physically separated from one another and go on to develop their own characteristics different from each other. This occurs because reproductive isolation brings about different gene frequencies in the new populations as compared to the original population. Really, it's to be expected that reproductive isolation would bring about changes between populations in this way. No mutations need be involved and there's no reason to suppose they are EVER involved.

It's simply a matter of different combinations or frequencies of alleles becoming characteristic in each of the separated populations. This is the natural result of the differences in gene frequencies working their way through each population over a few generations. Over time this brings about changes in the phenotypes characteristic of the new populations as a whole that differentiates them from each other more and more, sometimes to the point of approaching what the evolutionists would be inclined to call speciation. That depends on the degree of genetic variability that remains. The less genetic variability there is compared to the original population the more dramatic its changes will be, and the more likely it is that the populations will develop inability to interbreed with one another.

Is this speciation? This is an arbitrary definitional matter. It doesn't matter at what point population changes get called speciation, whether at this stage of practical differences bringing about lack of opportunity to interbreed, or behavioral disinclination to interbreed, or at the stage when isolation has brought about complete inability to interbreed because of genetic incompatibility, the effect is always that in isolation each population continues to elaborate its own separated gene pool and diverges further from the other.

Again, you don't need mutations to bring this about, merely different frequencies of alleles in each population.

And, as I've argued from the beginning of this blog, the result of these changes over time, especially with further splittings of the populations and further elaborations of the new gene frequencies brought about by the splitting, is reduced genetic variability that makes further evolution less possible, and ultimately impossible. The more evolution you have, the less evolution is possible. Evolution defeats evolution.

Oh well, they don't listen to such obvious simple contradictions of their beliefs. Maybe a creationist will come along and make the point eventually, and they'll ignore that too because they really don't care about science, only about justifying evolution.

But there's a brief statement of it just for the record.

By the way, they often complain that creationists offer no evidence for many interpretations such as the above, without ever recognizing that they have no evidence for their opposing interpretations either, but have only the familiar just-so story line.

They interpret the changes brought about by reproductive isolation as steps in open-ended evolution, simply because that's what the theory requires, not because they have any evidence for it. To their mind the simple fact that such changes do occur IS the evidence -- evidence for the theory of evolution. But there is no evidence for the open-endedness of the change process itself, that's just assumed. Darwin assumed it and it continues to be assumed.

Likewise they assume mutations as the engine that keeps it all going because the theory requires such an engine. You can get different kinds of finches out of the built-in genetic complement that belongs to finches, but you can't get an iguana out of a finch without the input of new genetic material or "information."

So instead of even recognizing that there is such a thing as a built-in genetic complement that defines a species (which is really the definition OF a species or Kind at the genetic level, that elusive definition they keep haranguing us creationists to produce), they assume that ALL genetic material is constantly being created by the processes of mutation and natural selection. Again, there is no evidence for this, they have to assume it because the theory requires it.

As a creationist I interpret the changes brought about by reproductive isolation as the effect of shuffling the frequencies of alleles that belong to the built-in genetic complement for the species. There is a natural limit to the changes possible BECAUSE there is this original complement of genetic potentials that can only be shuffled and reshuffled. It CAN play out to less and less genetic variability down any particular line of variation brought about by reproductive isolation, especially a series of reproductive isolations such as in a ring species. What is called "speciation" is really the result of this reduced genetic variability. New phenotypes develop from new frequencies of genes, but reproductive isolation itself over time reduces the genetic variability. This can produce dramatic new phenotypes, but there is a point that is reached when further variation becomes impossible. You may have a striking new variation (they call it a new species) but it may have such reduced genetic variability it can't change any further at all. Yes, like the cheetah. Thus bringing the processes of evolution to an end for that line of variation.

Mutations are of absolutely no use in this scenario, they only interfere with it, and in reality that does appear to be what happens, which is evidence for the scenario right there -- thousands of genetic diseases, thousands of "neutral" mutations that have simply not produced anything identifiable (although they have to be deleterious because they change the genetic code, which was originally perfect), and a very few known "beneficial" mutations that are highly questionable. These are the facts, although the theory of evolution says the opposite and has to interpret them away, as by claiming the beneficial mutations made the entire genetic code so are therefore hard to detect. The known facts, however, are on the creationist's side.

I have also suggested a scientific test that could prove all this, which is more than the evolutionist side can offer. All they have is theory, elaborated by theory, multiplied by theory, developed by theory and validated by theory. Fantasy in other words. No evidence.

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