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Author Topic:   Evolution Requires Reduction in Genetic Diversity
NoNukes
Inactive Member


(1)
Message 181 of 1034 (692155)
02-28-2013 10:22 AM
Reply to: Message 178 by Faith
02-28-2013 9:44 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Then you aren't really thinking about the reality of the situation which is not simple water in water out. "Water in" builds up the gene pool. That is NOT evolution if by evolution is meant the production of species.

No generating variation is not evolution. Evolution is variation + selection. Those processes need not be simultaneous. The end result over long periods can be speciation, but not every variation results in the kind of survival dominance that produces speciation.

Yes, but in the wild it would get blended in through the next generations which would form whatever phenotype or breed is going to form. Wild populations are not selected as breeds are but they are selected in the sense that they are nothing more than the mixing of an isolated gene pool with its own gene frequencies and that's the same thing as happens in breeding only the selecting forces are more random in the wild.

You are still not quite describing how evolution actually works.

Selection works only on traits that affect fitness in a given environment. Traits that do not affect fitness can still be passed on to descendents. However, some of those traits might be selected for if the environment changes.

Selection has not produced a homogeneous population of human beings in the last few thousand years.

Yes, but in the wild it would get blended in through the next generations which would form whatever phenotype or breed is going to form.

Let's be more specific about what "blending" means.

Only some individuals would have that non-beneficial and non deleterious change. Phenotype changes don't magically get distributed to entire populations unless they improve fitness to a degree that substantially punishes individuals not having the trait by making it too competitively hard for them to bear young. Only the mutant's descendents can get a particular mutation.

And if conditions change, or if some part of the species enters an environment in which conditions favor that particular phenotype, then we can get speciation due to the separation. In that case both species will exist and will be equally diverse to the pre-mutation population. But speciation need not begin at the same point in time at which the mutation appears.

We do have an enormous range of recognizable diversity in PHENOTYPE that doesn't occur in wild animals. Grizzly bears all look like grizzly bears

There is only one species of humans with some diversity. There are also 8 species of bears and grizzlies are just one type of brown bear. Some of the species of bear can interbreed. So just which grouping represents more diversity?

You DO agree that evolution IS the production of new species, don't you?

Evolution can produce new species, but the evolution is slow, and involves processes that are not themselves evolution.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass


This message is a reply to:
 Message 178 by Faith, posted 02-28-2013 9:44 AM Faith has responded

Replies to this message:
 Message 199 by Faith, posted 03-01-2013 1:02 PM NoNukes has responded

  
Taq
Member
Posts: 7670
Joined: 03-06-2009
Member Rating: 4.3


(1)
Message 182 of 1034 (692159)
02-28-2013 10:47 AM
Reply to: Message 155 by Faith
02-27-2013 7:41 PM


Re: Mutations Don't Add Anything That Could Rescue the ToE
I have not ignored them I've explained that they don't stop the march to genetic depletion, . . .

Where did you back this claim with evidence?


This message is a reply to:
 Message 155 by Faith, posted 02-27-2013 7:41 PM Faith has not yet responded

  
Taq
Member
Posts: 7670
Joined: 03-06-2009
Member Rating: 4.3


(1)
Message 183 of 1034 (692160)
02-28-2013 10:53 AM
Reply to: Message 160 by Faith
02-27-2013 8:31 PM


Re: Constant Increase In Genetic Diversity
Deleterious can mean doing damage that doesn't show up in a changed function except after many mutations have accumulated, and I'd guess such sleeper mutations as it were constitute the majority of the mutations out there. Just a guess.

The vast majority of mutations do not occur in genes, promoters, or transcription factors so I would say that the vast majority are neutral. Of the mutations that change protein sequences I would think that a fair amount are deleterious, much more so than those that occur in non-coding and non-regulatory DNA. We can also see negative selection removing these mutations by comparing the genomes of species. When we do so we find something very interesting. We find that mutations which do not change the amino acid sequence of proteins are more common in a gene than those that do change the amino acid sequence. This tells us that selection is removing deleterious mutations.

This doesn't change the fact that the DNA differences seen between species contain mutations that are beneficial to each species. We KNOW that they exist because we can see them. We can find them.

Prediction from this guess is that we'll be seeing lots more genetic diseases in the near future.

Why wouldn't selection remove them just as selection has been removing deleterious mutations since evolution started?


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Taq
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Posts: 7670
Joined: 03-06-2009
Member Rating: 4.3


(1)
Message 184 of 1034 (692161)
02-28-2013 10:58 AM
Reply to: Message 176 by Faith
02-28-2013 9:28 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Not if evolution is the production of new species/varieties/breeds. All you get from the addition of mutations is more traits that COULD be the basis of a new species, but as long as they aren't being selected, no, you aren't getting evolution.

They are being selected for, and this is shown by comparing our genomes to that of other apes. We can find patterns of positive and negative selection. I even highlighted evidence of positive selection in the case of the mc1r gene in pocket mice. Remember that?

No, it isn't a simple addition-subtraction thing. If alleles are flowing in you get stasis.

If alleles are flowing in and selection is changing allele frequencies then you have change in a species over time, otherwise known as evolution.

It is the BASIS for phenotypic change, because the gene pool IS the basis for phenotypic change, but you aren't GETTING phenotypic change until you get reproductive isolation and selection.

The phenotypic change shows up in the first organism that carries the mutation. The first pocket mouse with the mutation conferring black fur had black fur.


This message is a reply to:
 Message 176 by Faith, posted 02-28-2013 9:28 AM Faith has responded

Replies to this message:
 Message 207 by Faith, posted 03-01-2013 2:48 PM Taq has responded

  
Faith
Inactive Member


Message 185 of 1034 (692162)
02-28-2013 11:00 AM
Reply to: Message 179 by Percy
02-28-2013 10:02 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Faith writes:
Not if evolution is the production of new species/varieties/breeds. All you get from the addition of mutations is more traits that COULD be the basis of a new species, but as long as they aren't being selected, no, you aren't getting evolution.

They *are* being selected. The drain is selection in this analogy.

I know that, but if they are being selected and mutation is continuing to add to the gene pool you aren't getting a delineated recognizable species such as we see IN REALITY both in the wild and in breeding. This is all just some abstract idea that has nothing to do with what really happens. I don't know what you would get in this scenario but it's something blurry and constantly changing, NOT an identifiable new species which is what happens IN REALITY.

(You can't take the analogy much further - it was intended only as an illustration of how diversity is being added and taken away at the same time through the simultaneous processes of mutation and seleciton.)

See above. This is all theory gone bonkers, it has nothing to do with reality.

You are getting lots of new traits here and there within the existing population. That is not evolution.

Yes it is evolution. New traits are a result of evolution.

Is evolution about forming new SPECIES or about the myriad of different traits that show up in all populations? New traits show up in individuals in my scenario too, WITHOUT mutations.

The discovery of new species does not happen as often today as it used to, but it still happens with regularity, and new traits is what marks a new species.

But to GET that new species the traits have to be SELECTED AND ISOLATED. That's my point. The traits that constantly crop up in individuals in any fairly genetically diverse population, whether by mutation or by what I think it is, simply new combinations of existing alleles, do not constitute a new SPECIES unless selected, isolated and worked through the entire new gene pool. And THAT happens only when all the alleles for OTHER traits are suppressed, reduced, or eliminated = REDUCED GENETIC DIVERSITY REQUIRED TO FORM A NEW SPECIES.

New species of mushrooms were just discovered, identifiable as new because of unique differences in their spores (Two New Species of Mushroom Found in the Iberian Peninsula, Spain).

So? Should happen a lot in my scenario that you get new "species" from new mixes of old alleles. If you want to insist on mutations then realize that mutations are only going to keep delaying the formation of an identifiable new species by interfering with the gene pool from which the species is formed. But that isn't what happens in reality.

And when paleontologists discover a fossil with previously unknown traits they announce the discovery of a new species.

So? I would assume there were lots of variations in the ancient world too, which on my system would be formed from new traits built from new combinations of alleles that are brought to expression by selection and isolation just as they are in living species today, not requiring mutations. Again if mutations are involved you're only going to get something blurry or delay in the formation of a new species.

You do not get a new species with new traits simply by reducing diversity such as happens with breeding. That's why breeders do not create new species.

What you are calling new "species" is really just varieties or breeds of existing species, presumably having reached a point where they no longer interbreed with their mother populations, probably due to severe genetic depletion in some cases. And breeders could very well create a new species by that artificial definition if they keep at a particular breeding line without introducing new genes from time to time.

No, it isn't a simple addition-subtraction thing. If alleles are flowing in you get stasis. If alleles are flowing OUT you are getting new phenotypes or varieties or breeds or species. Really they are two separate processes.

Yes, of course they are separate processes. The faucet is analogous to mutation, and the drain is analogous to selection. And the alleles and genes flowing in are not the same alleles and genes flowing out. It isn't stasis.

With respect to the creation of new species it is stasis, it is not evolution. With mutations you are getting traits showing up in individuals here and there in a population that is not changing overall. That's stasis.

If the only way to get a ceramic pot out of a hunk of clay is to pare away all the stuff that doesn't look like the ceramic pot, you aren't going to get the ceramic pot if you carve a little then add a little clay somewhere else and so on. Carve and add carve and add, no, that is not how it works in reality.

It is the BASIS for phenotypic change, because the gene pool IS the basis for phenotypic change, but you aren't GETTING phenotypic change until you get reproductive isolation and selection.

Without mutation you cannot get phenotypic change into a new species because the population will only have alleles and genes already possessed by the main population.

What you guys seem not to appreciate is that the existing alleles and genes in a genetically diverse population are more than sufficient to form many many subspecies through selection and isolation of portions of the gene pool. New gene frequencies are all it takes, new combinations of old alleles. All the breeds of dogs came about from nothing more than this, also the cattle breeds, the cats, etc. etc. The alleles in the original wild populations are merely potential or latent, the traits they govern hidden from view as it were but when selected in new combinations they produce an amazing array of new traits and phenotypes. You do not NEED mutations to get all the variety in living things we see. Which is a different argument from whether mutations occur and contribute. In my system mutations are simply not needed, and can interfere.

And selection occurs all the time regardless of reproductive isolation.

By which you mean what? That some individuals die off? Selection isn't occurring in any sense that produces a new species if there isn't reproductive isolation of what is being selected. Selection means particular traits are favored and multiply down the generations for that reason. That's the ONLY way you are going to get new traits in new combinations in an entire subpopulation. i.e. a new "species."

Main populations are evolving, too, and possibly at a faster rate since they can draw upon a much larger inflow of new mutations.

NOT UNLESS THERE IS SELECTION. Genetic drift is a form of selection so that new subpopulations can form within larger existing populations, that's one way but it's slow. But the entire population isn't going to evolve because a motley collection of new traits isn't evolution. Some of them have to be selected in order to get evolution.

But that isn't evolution if evolution is the production of new species, which is brought about by the selection and isolation of a portion of the gene pool.

Again, isolation and selection are not sufficient to form a new species. Without mutations all you have is the same alleles and genes as the original population.

I'm glad this is coming out now because it is SUCH a mistake. The same alleles and genes in NEW COMBINATIONS is all you need to form myriads of new varieties from a large genetically diverse population. The new combinations are brought about by the change in gene frequencies brought about by the reproductive isolation of a reduced number of individuals, making for a new gene pool of interbreeding individuals, and that's how new breeds, varieties, species come about. The new combinations are powerful sources of new traits. You do not need mutations.

All mutation does is add to the gene pool and that is not evolution,...

Yes, mutations are part of evolution, and for the creation of novel traits they are the essential part.

The creation of novel traits occurs from new gene frequencies, new combinations of existing alleles.

All mutation does is add to the gene pool and that is not evolution, that's as you say the BASIS for phenotypic change but if selection does not act on it you do not have phenotypic change and do not have evolution.

Of course selection operates upon mutation. Always, constantly, all the time. How could it not? Selection operates on all expressed parts of the genome, whether newly arisen through mutation or part of the original genome.

You must be using the term "selection" in some other sense than I am. Selection is something that happens at the population level as I am using it. If perhaps you are talking about how sexual recombination works I guess that could be called selection with respect to individual traits, but I'm trying to keep the population level in mind which is where new species are formed.

That mutation and selection are always active is why both faucet and drain were open at the same time in the bathtub analogy.

Sounds plausible in the abstract but in reality it's not what happens, it does not describe what really occurs.


He who surrenders the first page of his Bible surrenders all. --John William Burgon, Inspiration and Interpretation, Sermon II.

This message is a reply to:
 Message 179 by Percy, posted 02-28-2013 10:02 AM Percy has responded

Replies to this message:
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ringo
Member
Posts: 16136
From: frozen wasteland
Joined: 03-23-2005
Member Rating: 3.1


(2)
Message 186 of 1034 (692163)
02-28-2013 11:03 AM
Reply to: Message 141 by Faith
02-27-2013 1:29 PM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Faith writes:

Because I interpret the facts from within a different explanatory system. Paradigm clash.


The clash is between an objective paradigm (the scientific one) and a subjective paradigm (yours). You have an axe to grind.

Faith writes:

Or simply: Because their conclusions are wrong.


Or because you're missing something.
This message is a reply to:
 Message 141 by Faith, posted 02-27-2013 1:29 PM Faith has not yet responded

  
NoNukes
Inactive Member


(1)
Message 187 of 1034 (692167)
02-28-2013 11:59 AM
Reply to: Message 185 by Faith
02-28-2013 11:00 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Selection is something that happens at the population level as I am using it.

Perhaps you are misusing it.

Selection operates on the phenotypes of individuals. How could it be otherwise? It is individuals of a a population that compete with their fellows and with members of other species for food, safety, shelter, and of course mates.

Of course when looking at evolution, the plight of any single individual is of a minor consequence. When only one individual is involved, it might well be that despite being the only member with wings, that individual still gets eaten by an eagle. The consequences of selection is on populations.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass


This message is a reply to:
 Message 185 by Faith, posted 02-28-2013 11:00 AM Faith has not yet responded

  
NoNukes
Inactive Member


(1)
Message 188 of 1034 (692168)
02-28-2013 12:04 PM
Reply to: Message 185 by Faith
02-28-2013 11:00 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
You do not NEED mutations to get all the variety in living things we see. Which is a different argument from whether mutations occur and contribute. In my system mutations are simply not needed, and can interfere.

In your system? Your system is about breeding and not evolution. Yes, mutations can interfere with breeding. But breeding does not produce new species.

Genetic drift is a form of selection so that new subpopulations can form within larger existing populations

This is just flat wrong. Genetic drift is the propagation of new traits in a population without selection.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass


This message is a reply to:
 Message 185 by Faith, posted 02-28-2013 11:00 AM Faith has not yet responded

  
Taq
Member
Posts: 7670
Joined: 03-06-2009
Member Rating: 4.3


(2)
Message 189 of 1034 (692173)
02-28-2013 12:50 PM
Reply to: Message 185 by Faith
02-28-2013 11:00 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
I don't know what you would get in this scenario but it's something blurry and constantly changing, NOT an identifiable new species which is what happens IN REALITY.

In reality, species do change over time. We call it evolution.

Is evolution about forming new SPECIES or about the myriad of different traits that show up in all populations? New traits show up in individuals in my scenario too, WITHOUT mutations.

Evolution is about speciation AND how traits appear in populations. It is both. Also, new traits also show up due to mutation. You are once again ignoring this fact. The black mice with the mc1r mutation are an example of this.

But to GET that new species the traits have to be SELECTED AND ISOLATED. That's my point. The traits that constantly crop up in individuals in any fairly genetically diverse population, whether by mutation or by what I think it is, simply new combinations of existing alleles, do not constitute a new SPECIES unless selected, isolated and worked through the entire new gene pool. And THAT happens only when all the alleles for OTHER traits are suppressed, reduced, or eliminated = REDUCED GENETIC DIVERSITY REQUIRED TO FORM A NEW SPECIES.

Before the reduction due to selection you get an increase in genetic diversity due to the accumulation of mutations. It is a sine wave, not an ever decreasing curve.

What you are calling new "species" is really just varieties or breeds of existing species, presumably having reached a point where they no longer interbreed with their mother populations, probably due to severe genetic depletion in some cases.

What we are calling species are genetically isolated gene pools. This causes different mutations to accumulate in each population, either through chance (neutral drift), or different selection pressures. What results is divergence. The two isolated populations become more diverse when compared to one another because they are accumulating different mutations.

What you guys seem not to appreciate is that the existing alleles and genes in a genetically diverse population are more than sufficient to form many many subspecies through selection and isolation of portions of the gene pool.

What you fail to appreciate is that species who share a common ancestor are more divergent than can be produced by a single ancestral gene pool. The differences between human and chimp genes is not due to different alleles in our common ancestor. Those differences are due to lineage specific mutations.


This message is a reply to:
 Message 185 by Faith, posted 02-28-2013 11:00 AM Faith has not yet responded

Replies to this message:
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NoNukes
Inactive Member


(1)
Message 190 of 1034 (692175)
02-28-2013 1:16 PM
Reply to: Message 189 by Taq
02-28-2013 12:50 PM


Re: Mutations Don't Add Anything That Could Rescue the ToE
The differences between human and chimp genes is not due to different alleles in our common ancestor. Those differences are due to lineage specific mutations.

Nice and succinct. These differences are the distinction between evolution and eugenics breeding programs which seems to be what Faith considers to be evolution.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass


This message is a reply to:
 Message 189 by Taq, posted 02-28-2013 12:50 PM Taq has not yet responded

  
PaulK
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Posts: 14716
Joined: 01-10-2003
Member Rating: 2.6


(1)
Message 191 of 1034 (692177)
02-28-2013 1:31 PM
Reply to: Message 173 by Faith
02-28-2013 9:08 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
quote:

Well, would you agree that if the faucet and drain are both open you aren't getting evolution? That is, you aren't getting the development of new varieties/species/breeds?

Definitely not.

quote:

If you are getting more increase in diversity than you are selection events you also aren't getting evolution, the development of new varieties/species/breeds.

Evolution isn't just the development of new species or subspecies. And anyway the increase in diversity is needed for the future development of new species and subspecies. (Your argument says so !)

quote:

{ABE: As a matter of fact you can't have both faucet and drain operating at the same time. The "drain" is supposed to stand for the selection/isolation processes but those bring about new phenotypes FROM the genetic pool. Must be more like add THEN subtract, add THEN subtract in reality}

That doesn't even make sense. The "faucet" is mutation and that is on all the time.

quote:

What you are getting is perhaps new traits appearing here and there in individuals within the population. But for evolution to occur, that is the development of a new population with new characteristics, a new "species," you MUST have reproductive isolation/selection.

Doesn't that seem true to you?


Well it seems poorly phrased. And it is far from clear that the usual model of speciation covers every case, It is certainly possible that some species come about from a more gradual transformation, affecting the entirety of the population,

quote:

This analogy really doesn't work though because this isn't a simple addition/subtraction issue and I wish I had a model for what it really is. If mutation is involved it could maybe be described as something like two steps forward, one step back. Add some diversity, knock it back with selection, add some more diversity, knock it back again.

You HAVE to knock it back, that is, you HAVE to reduce the genetic diversity to get a new phenotype, breed, variety, species, in the wild as well as in domestic breeding, though the most accessible example is what happens in domestic breeding. If mutation really is involved it could only be a start-stop sort of thing along the lines I'm describing here, the continual adding of mutations merely delaying the inevitable.


And here we come back to the idea of equilibrium. Now, let us grant that with the usual model of speciation the genes of the incipient species are less diverse than those of the parent population. It does not follow that they are less diverse than those of the parent population when it was an incipient species. This is the point you keep overlooking. The diversity of the parent population will have increased in the time between speciation events. Therefore there is no need for an inexorable reduction in genetic diversity.

quote:

Mutations would keep changing the gene pool which sets back the selection effects, but it can't keep them from occurring IF you're going to get new "species." If all you get is balance or stasis, water in water out, again you aren't getting the production of new species, you aren't getting evolution.

But of course you will because mutation does NOT act against selection in any way that would stop speciation. It does not prevent the loss of old alleles, it is NECESSARY to the rise of new alleles to replace the old. Your version of evolution is unworkable.


This message is a reply to:
 Message 173 by Faith, posted 02-28-2013 9:08 AM Faith has not yet responded

    
Dr Adequate
Member
Posts: 16083
Joined: 07-20-2006
Member Rating: 10.0


Message 192 of 1034 (692178)
02-28-2013 1:33 PM
Reply to: Message 185 by Faith
02-28-2013 11:00 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Faith, message #138 writes:

I'm using ONLY what I've learned from EVOLUTIONIST SCIENCE.

Faith, message #185 writes:

Genetic drift is a form of selection.


This message is a reply to:
 Message 185 by Faith, posted 02-28-2013 11:00 AM Faith has not yet responded

  
Percy
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Posts: 18257
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.0


(1)
Message 193 of 1034 (692214)
03-01-2013 9:15 AM
Reply to: Message 185 by Faith
02-28-2013 11:00 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Faith writes:

I know that, but if they are being selected and mutation is continuing to add to the gene pool you aren't getting a delineated recognizable species such as we see IN REALITY both in the wild and in breeding.

On the contrary, it's precisely what we see in reality. Almost every newly born organism possesses new mutations. The average human being possesses around 100 new mutations. Research has told us the mutation rate for many types of life, you can read about it over at the Wikipedia article on Mutation Rate.

Despite all these new mutations flowing into species population the world over, what you called "delineated recognizable species" continue to exist. That's because mutations, at least those that yield viable offspring, cause only tiny changes, and many are neutral.

Species are not eternal forms persisting forever. Species are plastic and change over time. As environments change species gradually change to adapt. Even when environments are constant species still change due to the genetic drift that is a result of the imperfect copying of reproduction that introduces new mutations.

This is all just some abstract idea that has nothing to do with what really happens.

It would be incorrect to say that this is only what we theorize might happen. It is precisely what we know happens because research has revealed it happening. We know that reproduction is almost always imperfect and causes mutations because there have been studies of life ranging from bacteria to mammals that reveal these mutations occurring. And we know the effects of mutations that create viable offspring are tiny. And we know that despite this species remain the same species over many, many generations. It probably takes at least 10,000 generations to produce a new species under normal circumstances.

I don't know what you would get in this scenario but it's something blurry and constantly changing,...

Yes, you're right. In reality species boundaries can be blurry, as illustrated by ring species that blend into each other at the boundaries of their territories. And yes, species are constantly changing, too, though not on human timescales.

That species boundaries can be blurry is responsible for the species definition problem. While we have no problem telling that cats and dogs are different species, its much more difficult when determining whether wolves and dogs are different species, or whether gray squirrels and red squirrels are different species. Biologists use a variety of methods to determine whether two phenotypically very similar species are the actually same species, but the most common is genetic analysis.

... NOT an identifiable new species which is what happens IN REALITY.

Any breeding population of organisms is an identifiable species, regardless of the particular qualities of the species.

(You can't take the analogy much further - it was intended only as an illustration of how diversity is being added and taken away at the same time through the simultaneous processes of mutation and seleciton.)

See above. This is all theory gone bonkers, it has nothing to do with reality.

No, it's not theory, it's reality. There is nothing that can stop the imperfect copying of reproduction that results in mutations, and environments are constantly imposing selective pressures on populations. All species populations are always simultaneously experiencing both mutation and selection. There's is no possible way to prevent either from occurring.

But to GET that new species the traits have to be SELECTED AND ISOLATED.

Without mutation you cannot get a new species. You can, for example, select for domesticity in wolves and foxes and find that other traits, such as curled tails, emerge at the same time, but neither domesticity nor curled tails are new traits. Rather, they were already present in the parent population but to only a tiny degree, and breeding develops and emphasizes these traits. But dogs and tame foxes can still breed with the original wolves and foxes because they are still the same species. Isolation and selection alone does not create new species. If it did then breeders would be creating new species all the time.

And THAT happens only when all the alleles for OTHER traits are suppressed, reduced, or eliminated = REDUCED GENETIC DIVERSITY REQUIRED TO FORM A NEW SPECIES.

Then why can't breeders create new species?

So? Should happen a lot in my scenario that you get new "species" from new mixes of old alleles.

No, it should not happen that a new species emerges by "new mixes of old alleles". If a subpopulation has all the same genes and alleles of the original population then these populations can still interbreed and are still the same species.

Plus your approach will never yield what we actually see in nature, which is that only very, very similar species have the same genes. Any species whose differences are more than slight will have different genes and alleles. Your conception will never produce different genes between species, which is precisely what we see in nature.

What we should see in nature were your view correct is a species heredity chart like this where the parent population has all the genes and alleles of all the daughter and grand-daughter populations while the daughter populations have only subsets of the parent's genes and alleles. And the grand-daughter populations should have subsets of the daughter populations' genes and alleles:

                                            parent pop
|
--------------------------------------------------
| |
daughter pop 1 daughter pop 2
| |
------------------------------- -------------------------------
| | | |
daughter pop 1a daughter pop 1b daughter pop 2a daughter pop 2b

What you need to find in order to have evidence that your scenario is something that actually happens is to find that every gene and allele in the daughter populations is already present in the parent population. And you need to find that every gene and allele in the granddaughter populations is already present in the daughter and parent populations.

But something like this has never been found, not in nature and not in breeding programs.

If the only way to get a ceramic pot out of a hunk of clay is to pare away all the stuff that doesn't look like the ceramic pot, you aren't going to get the ceramic pot if you carve a little then add a little clay somewhere else and so on. Carve and add carve and add, no, that is not how it works in reality.

No, that's pretty much how it works in reality, except for the part about having the specific goal of a ceramic pot. Evolution has no specific goals, just the general goal of adaptation to the environment.

What you guys seem not to appreciate is that the existing alleles and genes in a genetically diverse population are more than sufficient to form many many subspecies through selection and isolation of portions of the gene pool.

Of course we understand that one can form many subspecies from a single set of genes and alleles. But one cannot form a new species unless one has a supply of new genes and alleles.

Main populations are evolving, too, and possibly at a faster rate since they can draw upon a much larger inflow of new mutations.

NOT UNLESS THERE IS SELECTION.

I think you must be operating under the misimpression that main populations do not undergo selection. That would be incorrect. The processes of mutation and selection are always in operation in all populations everywhere.

The new combinations are brought about by the change in gene frequencies brought about by the reproductive isolation of a reduced number of individuals, making for a new gene pool of interbreeding individuals, and that's how new breeds, varieties, species come about. The new combinations are powerful sources of new traits. You do not need mutations.

This would be incorrect. A subpopulation with all the same genes and a subset of the alleles will still be the same species. It will still be able to interbreed with the main population. You cannot create a new species without new genes and alleles.

Of course selection operates upon mutation. Always, constantly, all the time. How could it not? Selection operates on all expressed parts of the genome, whether newly arisen through mutation or part of the original genome.

You must be using the term "selection" in some other sense than I am. Selection is something that happens at the population level as I am using it.

What I said is true of both individuals and populations. Let me say it again in terms that are specific to a population. Selection operates continuously upon all expressed portions of the gene pool of a population, including newly expressed portions due to mutation.

That mutation and selection are always active is why both faucet and drain were open at the same time in the bathtub analogy.

Sounds plausible in the abstract but in reality it's not what happens, it does not describe what really occurs.

Again, we think this is what occurs in reality because when we looked at reality this is what we observed happening. We observed that almost all reproductive events include a small number of mutations. We observed that the environment is always exerting selection pressures on populations.

--Percy


This message is a reply to:
 Message 185 by Faith, posted 02-28-2013 11:00 AM Faith has not yet responded

Replies to this message:
 Message 194 by NoNukes, posted 03-01-2013 10:50 AM Percy has acknowledged this reply

    
NoNukes
Inactive Member


(1)
Message 194 of 1034 (692234)
03-01-2013 10:50 AM
Reply to: Message 193 by Percy
03-01-2013 9:15 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
Faith writes:

And THAT happens only when all the alleles for OTHER traits are suppressed, reduced, or eliminated = REDUCED GENETIC DIVERSITY REQUIRED TO FORM A NEW SPECIES.

Percy writes:

Then why can't breeders create new species?

Exactly. And alternatively if creating species is about stomping out diversity, how is it that border collies, Danes, poodles, Labs (of all colors, world's best non human companions), Chihuahuas, bulldogs, spaniels(all types), Terriers, Shih Tzus, and yes, those mutated dachshunds and countless others are all of the same species.

Or this: If you can have mutations and still be human, then eliminating or preventing such variation or diversity is not a part of forming a human species.

Seriously, is there really anything left of this "End of Evolution" stuff? Because absent some new argument, I think a mud hole has been stomped in 'Evolution Requires Reduction in Genetic Diversity'.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass


This message is a reply to:
 Message 193 by Percy, posted 03-01-2013 9:15 AM Percy has acknowledged this reply

  
Faith
Inactive Member


Message 195 of 1034 (692246)
03-01-2013 11:40 AM
Reply to: Message 168 by PaulK
02-28-2013 1:48 AM


Re: Mutations Don't Add Anything That Could Rescue the ToE
But if a previously unknown heritable trait appears odds are that it is due to a mutation.

According to my model on the other hand, I would say that the odds favor its having been latent in the gene pool and then brought to expression in a combination that's rare for that gene pool through mere sexual recombination. There are many ways a trait could be latent, starting with its allele(s) being rare in that particular collection of gene frequencies, but also including its not being expressed except as the product of particular alleles for a number of different genes in combination, prehaps also involving formerly unexpressed recessive alleles, or even dominant alleles that don't show up as visible traits except in particular combinations.

What actually happens in reality is that the processes of evolution come to an end by running out of genetic possibilities.

In REALITY. This is demonstrated in breeding and it is demonstrated all the time in the wild where conservationists are concerned about species endangered by genetic depletion.

In actual reality there is no sign of this happening. That rapid depletion can occur and lead to problems (and often extinction) is entirely consistent with evolutionary theory. And let us note that the majority of cases are a consequence of human activity.

Yes I understand that the argument I'm facing here involves the claim that breeding methods don't model evolution in the wild, but it IS my argument that the principles are the same no matter who or what is doing the selecting.

Since it has been acknowledged by at least a few here that developing new breeds does involve reducing genetic diversity through mere selection of particular traits, and it's not an unreasonable idea that selection processes in the wild would operate in the same way, then the same kinds of processes would have to tend to the same conclusion, and they do, as exampled I believe in speciation events. Except of course in the wild the selection processes can be quite random such as migration and geographical isolation of a new gene pool which is not usually as small as those used in breeding, rather than caused by anything as actively selective as Natural Selection, though that may operate as well in some situations.

Seems to me we have Darwin himself for an authority on the similarity with domestic selection as he drew his inspiration for natural selection from his own experiences with breeding pigeons, and extrapolated his method to the random influences found in nature. He was able to produce quite an array of spectacular pigeon variations simply by selecting individuals to mate for chosen traits, and made the very reasonable observation that nature must do something similar in order to get the many variations we see there; such as the differences between mainland turtles and the turtles on the Galapagos, as well as all those different kinds of finches. He was right of course, he just went too far with it.

You all assume (without proof) that the traits chosen for breeding are created by mutation and there really isn't any way I can prove you wrong, but I don't see how you could claim that when the same trait is selected generation after generation with the effect that the chosen trait becomes strikingly large and elaborate, that mutations for each of those expansions and elaborations were the cause in each generation. Not if mutation is truly random you can't. The more reasonable explanation is that there is something in the genetic design itself that is capable of such elaborations.

You CLAIM that mutations keep adding diversity so that this doesn't normally happen but you do not KNOW that. You know that there ARE mutations but you don't know what they actually DO in the population. Again it's an article of faith based on your theory telling you that's what has to happen.

We know that there are mutations. We know that they increase diversity at the level of DNA sequences.

IF you are really observing a mutation and not confusing it with a normally occurring latent allele. But what KIND of diversity is NOT known in all cases. What is best known is the mutations that cause genetic diseases.

We know that mutations can have phenotypic effects.

Often deleterious ones.

Which is a pretty solid basis for a position.

Yes and no. You are all more or less willing to accept ANY kind of change as valid in supporting your position, including deleterious changes. That isn't impressive to someone who thinks evolution has to produce changes that can be useful to the organism, no matter how cleverly you rationalize the possibility of a disease process sort of becoming useful in various contexts. Which as far as what is actually known is concerned is a very rare occurrence and the only one I can think of at the moment is the fact that sickle cell anemia protects against malaria. Not a hopeful situation for evolution it seems to me but then who am I to have an opinion?

But we have more, we have all the evidence for evolution, which can't be explained by your theory.

You aren't listing your evidence here but as I've encountered it most of the actual evidence that IS evidence is just as good evidence for creation as it is for evolution, often better, but besides that your evidence often amounts to wild interpretations, as of the fossil record, which creationists rightly laugh at. Or finding that since the octopus has an eye most similar to a human eye that proves that the human eye evolved even though there is no known genetic path, or even theoretical genetic path, that could have brought that about. And that sort of nonsense is treated as "evidence." Chortle.

So we have much more than an article of faith, we have a quite solid position. All you have is your assumption that it can't happen.

Not an assumption, this is really and truly what I recognized had to be true as I was following out arguments on this subject. Certainly no assumption. It was a very exciting discovery as a matter of fact. But of course proving it is an uphill battle, especially with all the evolutionists trying to throw me over the cliff. Good thing I bounce well.

Edited by Faith, : No reason given.


He who surrenders the first page of his Bible surrenders all. --John William Burgon, Inspiration and Interpretation, Sermon II.

This message is a reply to:
 Message 168 by PaulK, posted 02-28-2013 1:48 AM PaulK has responded

Replies to this message:
 Message 196 by PaulK, posted 03-01-2013 12:26 PM Faith has not yet responded
 Message 197 by Taq, posted 03-01-2013 12:31 PM Faith has responded
 Message 198 by NoNukes, posted 03-01-2013 12:33 PM Faith has responded

  
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