What exactly is proved by Ring Species? A CREATIONIST'S PROPOSITION FOR A SCIENTIFIC TEST

[Source of diagram=PBS Evolution Library]
Thoughts about ring species. I've argued many times that this phenomenon demonstrates the inexorable reduction in genetic diversity with each "speciation event" or formation of a new variety of a Kind (new phenotype). It's a great example because many stages of variation (or change or evolution or speciation) are present, from a population that is probably fairly similar to the original to a population at the end of the ring that demonstrates the most changes from the original and may even be incapable of interbreeding with the original or others toward the beginning of the ring. Since reproductive isolation from the earlier populations is one of the definitions of evolution according to the theory, this is called Speciation in the strict sense and considered strong evidence that this is genuine macroevolution.

"Ring species" is the term for a series of more or less isolated populations of somewhat different versions of the same creature, chipmunks and salamanders being examples I've seen discussed, that are distributed all around a geographic barrier such as a mountain or mountain range or a body of water (the illustration shows salamanders found around the Joaquin Valley in California), each population descended from the previous in the ring. Such series demonstrate some of the principles of evolution (or speciation or variation) and are often taken as evidence for evolution.

It is apparently possible to identify the progression from one population to another, which follows a sequential path around the ring (or sometimes separately on each side of the barrier), as well as point to visible features that distinguish the populations from one another. There may or may not be complete reproductive isolation, meaning no interbreeding between the separate populations, and some interaction (or gene flow) may be retained in some cases, but for purposes of understanding the principles involved it's fair to describe each separate population as an isolated species or subspecies unto itself.

[The illustration to the right shows different variations of seagulls distributed around the northern Atlantic and Arctic oceans, and the picture below shows members of two different populations or subspecies at the opposite extremes of the ring]













So there's the concept. I hope it's clear.

Now. I've been arguing that whenever a new population or "species" or variation is formed, whether by natural selection or accidental selection by unpredictable events (bottleneck, founder effect) or by the migration of a part of one population to a new territory, where the new population becomes isolated and inbred among its own members, you get a new type of the creature, a variation, AND you always get it along with the loss of some genetic possibilities, specifically some that defined the previous population that are now changed in the new population and soon set it apart visibly from the previous.

So, if the former population had gray wings (or brown skin in the case of salamanders) you may now have a population with white wings (or striping in the case of salamanders) and changes in other traits as well. Genetically speaking what has happened is that alleles for the old coloring are now suppressed or even eliminated altogether in the new population while formerly unexpressed alleles are now being expressed in the new phenotype. The alleles that form the new traits may or may not be "mutations" but useful mutations are very rare and mutations are not needed for speciation in any case -- AND the same fate would meet the mutation as meets any other allele anyway, whether it is expressed in the new population or left behind in the old, the overall effect is still always reduction in genetic diversity in the new population as a whole.

The changes from the old to the new population demonstrate the famous definition of evolution as "a change in the frequency of alleles." But what is usually not taken into account in this definition is the fact that this change in frequency necessarily reflects a reduction in SOME of the alleles, at the extremes a complete elimination of them, and the only increase is merely a matter of the difference in proportions present in the different populations, the coming to expression of formerly suppressed alleles that were already present in the old population. That is, there is no actual increase in the alleles available, there are simply more of a kind, PROPORTIONALLY, of which there used to be proportionally fewer in the former population, but there is always a decrease in some alleles that defined the original population and in some cases a complete elimination of those formerly expressed alleles and this means an overall loss in genetic diversity.

As this process is repeated around the ring, perhaps over long periods of time though no more than enough years to establish a large and phenotypically homogeneous population, one established population becoming the basis for the migration of a few of its members to a new territory to form a new population, these few members as a group necessarily possess an even more limited complement of alleles from the former population, and the new frequency of alleles becomes the basis for a new phenotype that eventually emerges from the inbreeding of all the members. This is due to the isolation and inbreeding among members of the new population, again forming an identifiable new "species" or subspecies. And this "speciation" event is of course again accompanied by the expected REDUCTION in genetic possibilities, because the change in gene frequency that occurs with the founding of each new population REQUIRES that some of the alleles that characterized the phenotype of the former population are LOST to the new population, at least suppressed.

By the time many such migrations have occurred and there are many populations forming a ring, many alleles from the original population that started the ring are likely to be lost altogether in the more recently formed populations and certainly in the very last in the ring.

YOU DO NOT GET SPECIATION WITHOUT REDUCTION-TO-COMPLETE LOSS OF GENETIC VARIABILITY.

EVOLUTION DEFEATS EVOLUTION is my slogan. This expresses the observation that the very processes that form new phenotypes through change in gene frequency, are ALWAYS accompanied by a corresponding reduction in genetic diversity that ultimately reaches a point after many population splits beyond which no further variation/evolution/speciation is possible at all. If complete reproductive isolation occurs at this point then further evolution is completely impossible, though it may often still be possible for reproduction to be resumed with members of some former populations, but overall the tendency is always out to less variability and never to more and this contradicts all the expectations for the theory of evolution. The genetic situation ought to reflect this and ought to be measurable.

This is my claim.

NOW. Although I believe this is pretty close to a fact that ought merely to be recognized by anyone who will think it through, a fact I believe is supported by many observations made by conservationists at least, and very much the same genetic situation that domestic breeders face every time they try to isolate a highly specialized new breed, it ought to be possible to test this claim I've been making, only I don't have any way to do it myself.

It seems to me that ring species ought to be a very accessible proving ground for this claim. The claim predicts that whatever remains of the original population in a ring should have more genetic diversity among its members than the last in the ring, and there should be correspondingly less and less genetic diversity in each new population that is formed sequentially around the ring.

This ought to be testable. Proposed Method: All you need to do is analyze the genomes of whatever number of members of each of the populations in the ring will show what's needed to prove this one way or the other.

Prediction: The newest population should show quite a lot less genetic diversity than the oldest or first population, possibly even homozygosity at some gene loci, or radical total inability to vary in some characteristics beyond that point.

Intermediate populations should show incremental reduction of genetic diversity from the original to the newest population.

Conservationists know about the loss of diversity from migration and even natural selection and anything that isolates a small portion of a population from the greater population. They deal with practical consequences of this all the time. They don't want a few salmon, for instance, to break off from the main river population and head up a small tributary to breed because that will change the character of the fish in ways they don't want to happen by accident, and because this is a bottleneck situation that usually so drastically reduces the genetic variability of the new population that forms that it is vulnerable to environmental threats in a way the more diverse larger population is not.

This ought to be testable. I would really like to see it tested. Who do I talk to?

Perhaps the necessary observations of the genomes of the different populations in ring species have already been made in the service of some other scientific investigation and can just be brought out and looked at specifically for this purpose. That would be nice and easy.

I've dreamed up laboratory tests but they appear to be way too cumbersome. You start with a cage of mice (or whatever creature would work best for this purpose), let them breed among themselves for enough generations to establish a definitive phenotype for the population (which will unfortunately probably number in the thousands by that time, at least hundreds), then you send a few of them to another cage to inbreed among themselves until again a recognizably new homogeneous population is formed with a recognizably different appearance from the former population, and then you send a few from that new population to a new cage and so on until you have a dozen or more well-established new populations of mice that should show some pretty clear differences in characteristics from one another (by this time the mice will have taken over the laboratory), and then you take a look at their genomes. As I say for the above version of the experiment in the field, the newest population should show quite a lot less genetic diversity than the oldest or first population, possibly even homozygosity at some gene loci, or radical total inability to vary in some characteristics beyond that point; and there should be a graded series of reductions in genetic diversity from the original to the end population.

I really think this is obvious and shouldn't really need special testing but since it's doubted whenever I argue it in evolutionist venues it ought to be tested and it is obviously testable.

I would really like to see it tested. Any rich creationists out there who would like to fund this project?

(Yes, of course the evolutionists are going to rush in and assure us all that GIVEN ENOUGH TIME, like bazillions of years, mutation will overcome this effect anyway. It's a big fat delusion but we'll deal with that when we get there (though I've already answered the charge somewhere above). Meanwhile at least the claim that the phenomenon of Ring Species demonstrates macroevolution, and all similar and related arguments, should be dead and buried by this test.)

---CJA

==============================
P.S. I think some of my terminology and description are probably not precisely accurate but I also think anyone who knows about the phenomena I'm trying to describe should understand what I'm getting at and perhaps be able to put it in more precise language. And it doesn't affect the mechanics of the test I'm proposing anyway.