Evolution Requires Reduction in Genetic Diversity

Back in Message 480 I noted that you appeared to be using the term "gene death" to refer to two different things:

1. A gene becoming a pseudogene.
2. A gene suddenly being completely "wiped out" from a population's genome, e.g., as a result of the flood.

I can't be sure of this because I'm only inferring the definition from your usage, and I had to guess what you meant by "wiped out," and it's this uncertainty in how you're using the term that was the reason for ruling it out in this discussion. But if you'd like to provide a clear definition, which might be easier to accomplish now that you've withdrawn the claim that the flood caused substantial "gene death," then I'm fine with the term. My guess is that what you really mean by "gene death" is a gene becoming a pseudogene.Just in case anyone's curious, here's a bit of what Jerry Coyne says under the heading "Dead Genes":

quote:

---

"Atavisms and vestigial traits show us that when a trait is no longer used, or becomes reduced, the genes that make it don't instantly disappear from the genome: evolution stops their action by inactivating them, not snipping them out of the DNA. From this we can make a prediction. We expect to find, in the genomes of many species, silenced, or "dead," genes: genes that once were useful but are no longer intact or expressed. In other words, there would be vestigial genes. In contrast, the idea that all species were created from scratch predicts that no such genes would exist, since there would be no common ancestors in which those genes were active.
...
"And the evolutionary prediction that we'll find pseudogenes has been fulfilled - amply. Virtually every species harbors dead genes, many of them still active in its relatives...Out of about thirty thousand genes, for example, we humans carry more than two thousand pseudogenes. Our genome - and that of other species - are truly well populated graveyards of dead genes."

---

PARDON???????

• Lenski's experiment
• DOZENS of other experiments on bacteria, involving, FOR INSTANCE, immunity against antibiotics
• DOZENS of experiments on bugs gaining immunity against pesticides
• experiments on beetles - sexually reproducing animals
• experiments on fruit flies - sexually reproducing animals
• experiments on yeast
• genetic studies on Dachshunds and other animal breeds.

Explain to me, because it is getting interesting to know how this kind of psychology works, how you just dodge ENDLESS requests for addressing SERIES of points and questions and, without a blink of the eye, just "la, la, la, f*ck you, didn't read those" then manage to write: It is really breathtaking.Edited by Denisova, : No reason given.

Percy,AGAIN I ask you: is it normal in these EvC forum to just not answer questions and points made?Unfortunately the affairs here are not very different from the situation on Topix.
It's all dodging, ducking and evading here as well.I have asked Faith several questions and made numerous points and ALL of them still need to be addressed.And she STILL makes a lot of propositions without any shred of evidence. She even found something on that: Message 488,

quote:

---

No, because the scientific literature is in thrall to the evolutionist paradigm and assumes the opposite. Assumes I say, it is not evidenced, it's an interpretation imposed on all the data.

---

What the hell am I doing here on this forum.
There is no debate.Edited by Denisova, : No reason given.

Not at all. Gene flow would not be a yes or no answer but how much. What if you had two populations of 1,000 individuals and there was 1 migrant per year from each population that found its way to the other population. Would that be different from the situation where 100 individuals per year migrated? Of course it would. In which situation would it be more difficult for the two populations to differentiate? Message 571Natural selection is not the only factor involved; that's why we talk about drift, migration and mutation as well. I don't mean that researchers try to manipulate gene flow, but for two populations to differentiate enough to become distinct populations there needs to be reduced gene flow otherwise migration tends to reduce differentiation between populations. Not to a biologist. The question is why would gene flow be in only one direction? Why would a population emigrate to a region but there be no continued gene flow back and forth from the main population? Could it be that a physical barrier is important? If so, we already have a term for that type of situation - the founder effect. Why create a new term for a known phenomenon?Your whole argument rests on this one special case of migration, which has been well studied, but ignores other cases where there is not a founder effect. Or is your argument that the founder effect is the ONLY mode of speciation?HBD

If an individual migrates OUT of a population it moves INTO another population. If an individual moves INTO a population it has moved OUT of another population. You are only considering one population and one direction of gene flow. You need to keep the whole meta-population in mind. What you are trying to explain is how two subpopulations become different enough to be distinct populations that no longer interbreed. At first, they are both part of a larger meta-population. There are literally thousands of examples. You have been shown several, but you ignore them. The examples that fluctuate between morphs are more dramatic because you can "see" it happening. But there are plenty of examples were population shifts are clearly the result of natural selection. But I don't suppose you are up to reading up on them. Some concepts are difficult to understand and do take some explanation in order to grasp the concept. Like I started to bring up the Hardy-Weinberg equilibrium in a previous message but decided against it because I was afraid it would take too much explanation to get across the point of it so I left it out. However, it is a very important principle for understanding the concept of allele and genotypic frequency.Biologists (and lay persons) who take the time to study the concepts are not confused by them.HBD

I'm having trouble making sense of this, and it's possible others may also be having trouble figuring this out, so I'd like to take a stab at clarifying this. You're saying that genotypic frequencies can change without affecting gene/allele frequencies. This feels possible but unlikely to me.Let me spell out why I feel this way with a specific example. Let's say we have a population with 3 genes (named A, B, C) and 3 alleles for each gene (named A1, A2, A3, B1, etc...), and that they break down like this: But this says nothing about the percentages of the all the possible allele combinations in the population. Let's say the allele permutations in the population break down like this, and I've made these numbers consistent with the first table: Now if over time the frequency of A1-B1-C1 changed from 25% to 1% of the population while at the same time that A3-B3-C3 changed from 1% to 25% of the population, then the gene/allele frequency must also have changed. For example, the proportion of A1 in the population would decline from 78% to 54%, and the proportion of A3 would increase from 9% to 33%.So I think this demonstrates that if the genotypic frequencies change that the gene/allele frequencies will most likely also change. Do I have this right?

You have probably noticed that the number of creationists that frequent these discussion boards has declined considerably. They seem to all have retreated to their own forums such as Evolution Fairytale Forum. I felt the same way as you do at one time and spent some time debating over there. The quality of debate is MUCH worse over there. Well, I would say the debate over evolution versus creation is pretty much done. There are a few creationist holdouts who are willing to engage evolutionists, but very few. Many of those are complete wack-jobs, at least Faith is not like that, she is actually a fairly decent debater despite the difficulties. And at this time, Faith is pretty much the only creationist that frequents this forum.I debate here to learn new things (either from others or from research I do to prepare a post) and to practice presenting arguments. "Results" don't concern me much.I would be interested in debating some things that are still fairly controversial in evolutionary biology, like sympatric speciation, but don't get much response on those more detailed types of discussions.HBD

I will have to come back to this later today. It may take a rather lengthy explanation.HBD

"There is no debatable"You have to accept the limitations of the other side. Faith is doing this alone using a hypothesis she has concocted. She is not a creationist biologist. So there are limits in the quality of her answers.In a sense the debate is over. When Faith gets to the point of insisting that there is no evidence for your position, that is a tacit acknowledgement that your scenario works and that there are theories of evolution that do not require a reduction in genetic diversity. If you have done your own homework, then your success applies to the real TOE.On the other hand Faith's accusations that real biologists have missed evidence because they have TOE blinders on is an admission that she has no evidence on that point. Faith is increasingly turning around requests for evidence with insistence that we have no evidence regardless of what evidence we actually cite. You should take that as an admission that you have won the point.But don't expect an acknowledgement that a pet theory ten years in the making is dead. That is not coming.

Well, not quite, I've been here just for two weeks now, a bit too short to spot such decline.
Quite informative I must say.
It depicts a rather deplorable state of creationism I must say.I think we indeed should discuss topics that are still interesting to debate.I just peeked around on "Evolution Fairytale Forum".
After just 5 minutes I caught a terrible headache due to the claptrap there by creationists.
Bronze age mythology dwellers, lost in the 21st century, trying desperately to get a grasp on reality...

I do not mind people not being professional biologists.
I do not even mind the quality of her answer with respect to this lack of professional proficiency.
As a matter of fact, to me the person is always more important than his or her opinions.But I do bother about honesty.
If Faith would say that there is no evidence of her claims made but she wishes to still elaborate on her propositions to work it out where it leads to, I would gladly join that effort.But when I get comments like "no evidence" IN RETURN of bringing in evidence continuously, then it's "Holy Moses" time for me.But OK I will temper a little bit and change my debate intentions.

Oh brother, I can't believe how bad it really is.As I have been using the term "migration" some number of individuals move out of a population but not into a population, they strike out and create their own subpopulation in a new location. Have you actually been debating this with me for weeks and weeks and don't get this much? What could I have done to get this across? That's how ring species work too, leaving one to start another with their own new proportions of alleles. Although it's not all migration, the diagrams on the Speciation page show the same basic principle. They aren't going from one population to another, they are forming their own subpopulations, not always by going anywhere but the principle is the same. I've been thinking about this for at least ten years now and you don't know what you are talking about. I know far better than you the "meta population" context and I've been describing what happens quite accurately, INCLUDING referring to that "meta population context." Sheesh. Blech. Your problem is that you are new to all this but you think you know it all. I need to use terminology in a different way from evolutionists BECAUSE I'M NOT AN EVOLUTIONIST. I try to be clear about my usage but somebody who is slavishly sophomorically learning the ToE just brickheadedly insists on the status quo and then treats ME like I'm the one at fault. Blech.n Who needs it, why bother.I started out reading about Hardy Weinberg years ago. If it had any relevance to my argument I'd have brought it up myself.Now I'm so disgusted with this discussion I've lost any interest in ever talking to you again. Why bother. Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Not exactly. I am saying that inbreeding alone will not change the allele frequency, it will only change the genotypic frequency; shuffling the alleles into homozygotes. In order to change the allele frequency you need mutation, selection, drift or migration. Yes, if alleles are introduced into or removed from a population it will change genotypic frequency. But inbreeding doesn't do that. In order for this to happen, alleles need to be removed or added to the population. Inbreeding alone doesn't do that.---------That should clarify what my point was but I will go ahead and explain what inbreeding actually does just to make sure it is clear.For a population that is breeding completely at random we expect that the genotypic frequency will reach an equilibrium point according to Hardy-Weinberg (of course all this will assume that there is no mutation, selection, drift or migration since we are focusing on the effect of inbreeding). So if the frequency of allele 'A' is 0.5 and the frequency of allele 'a' is also 0.5 then the genotypic frequency will be 0.25 'AA', 0.50 'Aa' and 0.25 'aa'. As long as mating is random and there is no selection, mutation, drift or migration these frequencies will not change.Inbreeding is non-random mating where individuals are more likely to mate with a closely related individual than they would by chance. The most extreme version of this is selfing, where there is 100% chance that an individual with mate with a closely related genotype (itself). So here's what happens... start with the same genotypic frequencies as above

Start Freq	1st gen Cross	Resultant Freq	F1 Freq	2nd gen Cross	Resultant Freq	F2 Freq
'AA' (.25)	x 'AA'-->'AA' (1)	.25 x 1 = .25	.375	x 'AA'--> 'AA' (1)	.375 x 1 = .375	.438
	x 'Aa' --> 'AA' (.25)	.50 x .25 = .125	-----	x 'Aa' -->'AA' (.25)	.25 x .25 = .062	-----
'Aa' (.50)	x 'Aa' -->'Aa' (.50)	.50 x .50 = .25	.25	x 'Aa' -->'Aa' (.50)	.25 x .50 = .125	.125
	x 'Aa' -->'aa' (.25)	.25 x .25 = .125	-----	x 'Aa' -->'aa' (.25)	.25 x .25 = .062	-----
'aa' (.25)	x 'aa' -->'aa' (1)	.25 x 1 = .25	.375	x 'aa' -->'aa' (1)	.375 x 1 = .375	.438

Notes about table: 1) 1st and 2nd gen cross is the frequency of resultant offspring 2) Resultant Freq is the original (or F₁) times the offspring frequency. 3) F₁ or F₂ Freq combines frequency of homozygotes produced by 'Aa' x 'Aa' and homozygotic crosses.After just two generations of complete inbreeding the genotypic frequencies have changed to:
'aa' = .438
'Aa" = .125
'AA' = .438.Now let's figure out the allele frequencies.
'a' = .438 + (.125/2) = .50
'A' = .438 + (.125/2) = .50.So the allele frequencies have not changed but the genotypic frequencies have shifted from being 50% heterozygous to only 12.5% in just 2 generations.Thus, inbreeding alone does not change allele frequency, only shuffles the alleles into homozygotes. So, there is no reason to think that inbreeding can cause enough differentiation to prevent interfertility since the same genotypes existed in the original population, but now, the proportion of genotypes has now changed.HBD

So... I'm an idiot, again? Nice. Typical. Rather than address the arguments...HBD

Rather than address the arguments? That's the best you can do? Blech.