Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 88 (8927 total)
Current session began: 
Page Loaded: 08-23-2019 9:12 PM
27 online now:
AZPaul3, jar, JonF, RAZD (4 members, 23 visitors)
Chatting now:  Chat room empty
Newest Member: Jedothek
Post Volume:
Total: 860,348 Year: 15,384/19,786 Month: 2,107/3,058 Week: 481/404 Day: 85/63 Hour: 1/3


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
1
23456
...
15NextFF
Author Topic:   MACROevolution vs MICROevolution - what is it?
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 207 of 908 (816691)
08-09-2017 1:50 PM
Reply to: Message 204 by Taq
08-09-2017 10:44 AM


the usual silly wrong linear analogy
To use an analogy, walking to the curb is microwalking and walking to the store is macrowalking. It seems that there is an arbitrary line between micro and macro.

'cept it isn't cuz evolution, meaning the development of new varieties. requires the loss of the genetic material for other varieties. You don't get a Husky without losing all the alleles for the salient characteristics of a Chihuahua. You don't get a blue wildebeest without losing the characteristics of a black wildebeest. If you have a series of population cuts that produce new varieties or races you will soon reach a point in that line of evolution where you've run out of genetic material for further evolution.

So the relevant analogy would be more like sculpting a statue. You get the desired image by getting rid of everything that doesn't belong to that image.* There may be better analogies but I haven't been able to find one that really does it.

===

*Of course if you're carving in stone it's not possible to add more stone, as in mutations; and if you're building it in clay you won't have your finished image for long if you keep slapping on more clay, as in mutations.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 204 by Taq, posted 08-09-2017 10:44 AM Taq has responded

Replies to this message:
 Message 209 by Taq, posted 08-09-2017 2:39 PM Faith has responded
 Message 502 by DOCJ, posted 08-17-2017 10:57 PM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 210 of 908 (816695)
08-09-2017 2:46 PM
Reply to: Message 209 by Taq
08-09-2017 2:39 PM


Re: the usual silly wrong linear analogy
Mutations only help if they occur before selection. Afterward they defeat the purpose of the selection, which is the evolution of a new variety.

Take the famous peppered moth example. The source of the black moth may be a mutation, but the whole population of black moths is the result of selecting out all the white moths. There may still be the genetic material for the white moths in some individuals of the population of black moths so that you can still get a new population of white moths under new selection pressure.

But the principle is that to get a population of the new variety requires losing the genetic stuff for the other variety.

QED

Edited by Faith, : No reason given.


This message is a reply to:
 Message 209 by Taq, posted 08-09-2017 2:39 PM Taq has responded

Replies to this message:
 Message 211 by Taq, posted 08-09-2017 2:54 PM Faith has responded
 Message 213 by PaulK, posted 08-09-2017 3:15 PM Faith has not yet responded
 Message 215 by CRR, posted 08-09-2017 6:18 PM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 212 of 908 (816697)
08-09-2017 3:08 PM
Reply to: Message 211 by Taq
08-09-2017 2:54 PM


Re: the usual silly wrong linear analogy
Yeah yeah yeah of course selection isn't purposive but the point is that it's considered to be the way new varieties emerge that have survival value over the parent population, so in a way it looks teleological.

Sure you can get a new variety from a mutation if it's selected, so what? For it to form a population of this new variety nevertheless requires the loss of all the other varieties. Always the end result of the selection processes is loss. You keep adding stuff without seeing that all it does is produce new varieties or kill old varieties which is a dead end for the ToE.


This message is a reply to:
 Message 211 by Taq, posted 08-09-2017 2:54 PM Taq has responded

Replies to this message:
 Message 214 by Taq, posted 08-09-2017 3:41 PM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 216 of 908 (816719)
08-09-2017 10:36 PM
Reply to: Message 215 by CRR
08-09-2017 6:18 PM


Re: the usual silly wrong linear analogy
But the principle is that to get a population of the new variety requires losing the genetic stuff for the other variety.

There is no requirement of evolution theory that the parent population go extinct (although this is often the eventual result).

What are you talking about? I said nothing about the parent population going extinct, I said nothing about the parent population at all. It may still go on as usual if its numbers are high enough, and may yet be the source of other lines of variation as well. It's in the separated lines of variation that the loss has to occur that I'm talking about, a subpopulation that is actively evolving.

In the case of the Peppered Moth the white variety was never completely eliminated and today both varieties are common.

So? Did I say anything different?

However beneficial information adding mutations are very rare. Most cases of new varieties and species is due to partitioning of the original gene pool so that each of the new ones has less genetic diversity than the parent population

That's my usual argument. What you are calling partitioning is the formation of a daughter population and it's a form of selection, and the end result in each daughter population is what I'm talking about here, the trend to loss of genetic diversity that makes evolution ultimately impossible. And it can occur without mutations at all since the variations are built into the genome, and you are going to get new gene frequencies whatever their source; but I usually allow for the evo assumption of mutations because the same thing happens in either case and they are so fond of mutations there's no point in making an issue of it for that part of the argument.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 215 by CRR, posted 08-09-2017 6:18 PM CRR has not yet responded

Replies to this message:
 Message 219 by Taq, posted 08-10-2017 10:54 AM Faith has not yet responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 217 of 908 (816720)
08-09-2017 10:51 PM
Reply to: Message 214 by Taq
08-09-2017 3:41 PM


Re: the usual silly wrong linear analogy
Yes the other varieties survive in other populations. When you get a Great Dane by losing all the genetic stuff for all the other breeds, you aren't eliminating all the other breeds themselves that exist elsewhere you are only eliminating their genes in the Great Dane breed. It's in the formation of a breed that the processes of evolution are seen, how the formation of new phenotypes REQUJRES the loss of other genotypes. Pure breeds are often homozygous for all their salient traits. But those traits are different in each breed of course. I'm always talking about the evolving LINE, not the entire population. It's where new phenotypes are forming that the loss of genetic diversity has to occur. It's where EVOLUTION is occurring in other words that you are losing genetic diversity. WHEREVER you are getting new phenotypes you are losing genetic diversity. There may be plenty of genetic diversity left in other populations, even other evolving lines and there may be hybrids forming as well, but the trend is always to reduction where you are getting new phenotypes in an isolated population. We could talk complicating factors but not until this basic principle is acknowledged. And it is basic, it has to happen if you are getting new phenotypes, new variations, new subspecies etc.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 214 by Taq, posted 08-09-2017 3:41 PM Taq has responded

Replies to this message:
 Message 218 by Taq, posted 08-10-2017 10:50 AM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 220 of 908 (816742)
08-10-2017 11:20 AM
Reply to: Message 218 by Taq
08-10-2017 10:50 AM


Re: the usual silly wrong linear analogy
The formation of new phenotypes only requires mutations. Selection for an already existing phenotype is not the formation of new phenotypes.

I don't have time to respond to all of this right now, but I haven't made myself clear about this: I'm not talking about just getting A new phenotype within a population, I'm talking about getting a whole new population characterized by new phenotypes, which is clearly illustrated by domestic breeding. You get a whole new breed, a whole new population with its own characteristics. The new phenotypes are brought about by changed gene frequencies due to the formation of an isolated daughter population which may be caused by natural selection or just random migration, or intentional selection in the case of domestic breeding. As the new characteristics become established in the new population they replace the characteristics of the parent population, and eventually lose them altogether if the same selection pressures continue. That's how you get a new breed or species. You DO have to lose the old for the new to become established. Have to.

And what I'm saying is that genetic loss, being necessary to evolving this new species or breed, characterizes evolution itself, and this is not recognized. We know it's not recognized because of all the silly wrong linear analogies that are given to describe it, ignoring the necessity of genetic loss. Evos are always saying how macroevolution is just a continuation of microevolution, just putting one foot in front of the other, a difference between walking to the curb or walking a mile and so on, but it is not. This ignores the fact that you have to lose traits and their genotypes in order to get a population with its own characteristic new traits. HAVE TO.

It does not matter whether the new population incorporates a mutation or not. If it does that means the mutation is a high frequency allele in the new context and its characteristics will show up in the new phenotypic presentation. Meanwhile the OTHER traits are being lost while the new are getting established, the new including your mutation.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 218 by Taq, posted 08-10-2017 10:50 AM Taq has responded

Replies to this message:
 Message 221 by PaulK, posted 08-10-2017 11:44 AM Faith has responded
 Message 222 by Taq, posted 08-10-2017 11:55 AM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 223 of 908 (816776)
08-11-2017 7:39 AM
Reply to: Message 221 by PaulK
08-10-2017 11:44 AM


Re: the usual silly wrong linear analogy
It is recognised as a part of evolution, but it is only a part.

It is obviously not recognized even as a part or we wouldn't keep getting these silly wrong linear analogies that pretend there is a straight unimpeded line from microevolution to macroevolution. Since there must be genetic loss because of microevolution in the formation of a new variety or race or species, getting from there to further evolution is really not even possible at all.

We know it's not recognized because of all the silly wrong linear analogies that are given to describe it, ignoring the necessity of genetic loss.

So people actually prefer standard evolutionary theory to your personal opinions. Just because reason and evidence are against you. That may seem silly to you but it isn't

Look, I understand you don't like the fact that your precious argument is foolish and wrong but that is the way it is. You can be as arrogant and rude as you like but you can't beat the truth that way.

The evidence and truth happen to be on my side despite entrenched evo denials. Some honest clear thinking would show an honest person that this is not opinion but fact, and all your insults only serve to distract from this simple fact. What's "foolish" is the wrongheaded denials of a simple logical proof that macroevolution is dead in the water-- though of course very understandable considering the investment you all have in the ToE . I am of course making what must seem like an outlandish claim, but truth is truth.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 221 by PaulK, posted 08-10-2017 11:44 AM PaulK has responded

Replies to this message:
 Message 224 by PaulK, posted 08-11-2017 8:18 AM Faith has not yet responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 225 of 908 (816780)
08-11-2017 9:14 AM
Reply to: Message 222 by Taq
08-10-2017 11:55 AM


Re: the usual silly wrong linear analogy
Faith writes:

don't have time to respond to all of this right now, but I haven't made myself clear about this: I'm not talking about just getting A new phenotype within a population, I'm talking about getting a whole new population characterized by new phenotypes, which is clearly illustrated by domestic breeding.

It is also illustrated by the pocket mice and peppered moths we have discussed previously. In both cases you start with just one color. Over time, you get a mixed population of two colors. How is that not an increase in genetic diversity?

I'm not denying increases in genetic diversity through mutation, that's not the point. When you are getting the whole population of black moths you are losing the genetic stuff for the peppered moths, and vice versa. This is the point: when you are actually getting a whole new population characterized by a new phenotype (or set of new phenotypes due to changed gene frequency), in this case a population of black moths, you are losing, you must lose, all the genetic stuff for the traits the new traits are displacing, in this case the peppered moths. (Same with the black and white mice. White population has lost the genetic substrate for black; the black population has lost the genetic substrate for white) The other trait or traits may still be present in small numbers so still recoverable under changed selection, but the principle still holds, and when the former traits, the peppered moths, become selected again it will operate in the same way: you'll get a population of peppered moths without black moths or their genetic underpinnings. We are getting a very limited picture of microevolution in this example, nothing that could possibly proceed to macroevolution, but it does demonstrate the principle that to get a new variety requires genetic loss.

Faith writes:

The new phenotypes are brought about by changed gene frequencies due to the formation of an isolated daughter population which may be caused by natural selection or just random migration, or intentional selection in the case of domestic breeding.

False. Those new phenotypes are brought about by mutations in the parent population. New phenotypes will continue to appear in the daughter populations since mutations never stop. If one allele for one gene is selected for this does not stop the process of mutation. It continues in every generation. It is the accumulation of these mutations over time that results in macroevolution.

A mutation changes a single allele in a single gene. Getting a whole lot of single-allele phenotypes in a population isn't evolution and in most cases you aren't even going to get that much as the mutations most often don't change the phenotype. And even if a mutation/phenotype spreads through a population, by drift or positive selection, that is just another case of microevolution, and what's happening while it spreads? It's displacing the alleles for another trait, that other trait and its allele being the genetic loss I'm talking about. If the new trait is strongly selected it may come to replace the former trait altogether and you'll have the whole new population with the new trait I'm talking about --- because of the LOSS I'm talking about of the other trait and its genetic substrate.

In other words the process I'm talking about occurs no matter where you are getting a changed population characterized by a new phenotype or set of phenotypes. I focus on the situation where a portion of a population is physically isolated from the parent population because it makes the case more clearly, but the principle applies wherever one set of traits is replacing another -- you're losing the replaced traits and their genetic substrate. So bring on the mutations. If they are selected they demonstrate the same principle I'm talking about. They do not get you to macroevolution because selection makes macroevolution impossible.

Faith writes:

And what I'm saying is that genetic loss, being necessary to evolving this new species or breed, characterizes evolution itself, and this is not recognized.

You won't recognize the increase in genetic diversity produced by new mutations.

As I say above, increase in genetic diversity doesn't change the pattern I'm talking about, microevolution which leads to a new variety or species. A motley collection of new alleles isn't microevolution; you have to have selection of a new trait or set of traits and their alleles to get microevolution, and selection involves losing the old traits while the new traits proliferate. It really doesn't matter whether the new traits are due to mutations or just changed gene frequencies of old alleles, the same processes have to occur in either case.

We already recognize that mutations in the human lineage have replaced alleles that existed in the common ancestor of humans and chimps.

Well, you don't know this at all, you assume it. However, even this scenario also requires loss, loss of the "replaced alleles." It's impossible because you'd reach the point long before you got a human from a chimp beyond which further evolution couldn't happen because you've run out of genetic diversity. The chimp genome is only going to produce chimp alleles for chimp characteristics, and mutation is only going to come up with variations on the chimp alleles for chimp characteristics because that's what the chimp gene does, it doesn't do human characteristics, it does chimp characteristics, and active microevolution is going to make all those genes homozygous over some number of generations, beyond which point further evolution just plain cannot happen. Oh maybe a fluke mutation for purple fur will pop up, maybe it might even be selected, so that you get purple chimps and lose a bunch of gray ones in the process. Maybe the purple ones will kill all the gray ones too. Or vice versa. But anyway. macroevolution is a pipe dream because genetic loss always attends genetic change from population to population.
'

You won't recognize that this is an ongoing process and that it never stops due to the fact that mutations continue to appear and continue to be selected for.

Um, continue to appear, yes, but continue to be selected for? Everything you all say about the nature of mutations puts the lie to that claim. But even if it were true the processes I've described above have to operate on your selected mutations as described. Selection can only occur by eliminating the traits not selected. You may get a new race of chimps but they will be chimps nevertheless.

The best you'll ever get from mutations is variations on the chimp genome, you'll never get anything but a chimp and while you are getting a new purple chimp or a chimp with too many toes, you have to lose the genetic material for the old chimp so you'll eventually run out of the genetic material needed for further evolution.

This is how we get two co-existing species with different genomes, otherwise known as macroevolution.

What marvelous faith you show! You actually believe that changes in DNA sequence would get you from a chimp to a human being? Have you noticed that all you've done is assert this here by the way? How it could possibly happen in reality is not even suggested, it's entirely a figment of your imagination. And the REAL reality is that when you do get phenotypic change you have to lose genetic diversity and eventually that has to lead to inability to change further.

You HAVE TO have mutations to select for, and those mutations increase genetic diversity.

Even if so it's the selection that runs you out of genetic diversity, and it's the selection that brings out the new phenotypes that form the new variety or species, and in order to do that it eliminates the genetic substrate for all the other traits. Those other traits may still be present in the parent population, but they aren't present in whatever population is based on selection of OTHER traits.

If you can figure out how to get macroevolution without selection, go for it, pile up all the mutations you like, but selection is always going to lead to genetic loss and eventual inability to evolve further.

You HAVE TO have an accumulation of those mutations over time because there is no mechanism that will prevent it.

As I say above, if you can show how the accumulation of mutations can lead to macroevolution without selection, go for it. But selection, even random selection, anything that furthers one trait over another so that a new population with the new trait emerges as a variety or species unto itself, has to work on those mutations, and it's selection that reduces genetic diversity, and if continued eventually will make further evolution impossible.

Again, try getting evolution without selection.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 222 by Taq, posted 08-10-2017 11:55 AM Taq has responded

Replies to this message:
 Message 227 by Taq, posted 08-11-2017 10:49 AM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 226 of 908 (816782)
08-11-2017 10:32 AM
Reply to: Message 222 by Taq
08-10-2017 11:55 AM


Re: the usual silly wrong linear analogy
If it were true that you got a whole lot of new phenotypes in the daughter population you'd never get a recognizable variety or species, but we know that's not so. What you seem to be imagining is constant increase without the selection because if you take the selection into account you have to see that the increase is not evolution, it's just the stuff that selection works on, and selection is what brings out the new phenotypes that make for new varieties and species. Selection could be the proliferation of a trait or set of traits within a population or physical separate of a part of the population, but any way it happens involves losing some genetic stuff for some traits in order to bring out others.

Again, add all the mutations you like, unless selection makes a new variety or species from them you aren't getting evolution, but the process of getting a new variety or species means losing genetic diversity. Always. And if you keep adding mutations you're just getting a dizzy exchange of increase followed by decrease followed by increase,l you aren't getting evolution.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 222 by Taq, posted 08-10-2017 11:55 AM Taq has not yet responded

Replies to this message:
 Message 228 by PaulK, posted 08-11-2017 10:49 AM Faith has not yet responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 229 of 908 (816805)
08-11-2017 1:08 PM
Reply to: Message 227 by Taq
08-11-2017 10:49 AM


Re: the usual silly wrong linear analogy
You have already agreed that mutations provide new genetic diversity, so there is no running out of genetic material.

If you aren't getting the formation of a new variety or species then you can have all the genetic diversity you want. But if you are getting a new variety or species then you are losing genetic diversity. Take your pick.


This message is a reply to:
 Message 227 by Taq, posted 08-11-2017 10:49 AM Taq has responded

Replies to this message:
 Message 230 by Taq, posted 08-11-2017 1:10 PM Faith has responded
 Message 231 by PaulK, posted 08-11-2017 2:06 PM Faith has responded
 Message 236 by dwise1, posted 08-11-2017 3:31 PM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 232 of 908 (816810)
08-11-2017 2:38 PM
Reply to: Message 231 by PaulK
08-11-2017 2:06 PM


Re: the usual silly wrong linear analogy
Faith writes:

If you aren't getting the formation of a new variety or species then you can have all the genetic diversity you want.

Which is fatal to your argument. Allow genetic diversity to increase in between speciation events and there is no longer an argument for inevitable decline.

But it doesn't increase in reality. If it did you'd get only the see-saw effect I described, which is not evolution because evolution produces identifiable varieties, and macroevolution supposedly takes off from an established variety or species. You get your species that can no longer interbreed with its precursors and supposedly that is the platform for macroevolution. A big fat joke since such a species must be too genetically reduced for much further change if any, let alone change on the order of what would be needed in the direction of a new species. Really, the ToE is just fantasy upon fantasy.

You could even get a species as genetically depleted as the cheetah or the elephant seal, as the result of microevolution, and it would be absurdly celebrated as macroevolution.

You'd have to look at evidence to see if there were signs of this assumed decline (and the evidence says - very strongly - NO)

Every selective breeding program in history says a resounding YES. That's why breeding methods had to be modified in recent years, because they lead to genetic depletion which causes genetic diseases. Since all that has happened in breeding is a speeded-up version of what happens under natural selection in the wild (do you want to argue with Darwin about that?), or random selection of the sort seen in the formation of ring species by migration of portions of the previous population, we can infer that the same processes lead to the same results: reduced genetic diversity as the necessary cost of developing new species or breeds or varieties.

As long as there are identifiable species and identifiable breeds, some of which are known to have lasted hundreds of years at least, and many probably more than that, even some for which there is no doubt written evidence, as long as there are identifiable varieties, species and breeds, my argument stands because adding mutations at any appreciable rate would destroy their identifiable characteristics.

You do exert yourself quite admirably in defense of the ToE, if exertion in the absence of simple logic is a virtue, though the effort is Quixotic in the end.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 231 by PaulK, posted 08-11-2017 2:06 PM PaulK has responded

Replies to this message:
 Message 234 by PaulK, posted 08-11-2017 3:09 PM Faith has not yet responded
 Message 235 by Taq, posted 08-11-2017 3:13 PM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 233 of 908 (816811)
08-11-2017 2:44 PM
Reply to: Message 230 by Taq
08-11-2017 1:10 PM


Re: the usual silly wrong linear analogy
You are gaining genetic diversity because of mutations. I don't have to pick between your false choices.

You are getting genetic diversity without evolution. This thread is about evolution. The silly linear model of microevolution to macroevolution is wrong because microevolution reduces genetic diversity, without which evolution has to come to a halt. If you keep throwing in mutations you bring it to a halt in another way, because it takes selection to produce a new species. Either way evolution comes to an end. The ToE is impossible no matter how you look at it.


This message is a reply to:
 Message 230 by Taq, posted 08-11-2017 1:10 PM Taq has responded

Replies to this message:
 Message 271 by Taq, posted 08-14-2017 10:42 AM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 237 of 908 (816829)
08-11-2017 6:40 PM
Reply to: Message 236 by dwise1
08-11-2017 3:31 PM


Re: the usual silly wrong linear analogy
I saw a demonstration of Dawkins' silly little program years ago and realized that it assumes the same linear development I'm objecting to here, and I suppose your version does also. It's very cute and it's fun to watch it do its thing, but it doesn't take into account the FACT that to get a new variety or species requires the loss of genetic material for other phenotypes.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 236 by dwise1, posted 08-11-2017 3:31 PM dwise1 has responded

Replies to this message:
 Message 239 by PaulK, posted 08-12-2017 2:37 AM Faith has responded
 Message 369 by dwise1, posted 08-15-2017 3:29 PM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 238 of 908 (816832)
08-11-2017 7:17 PM
Reply to: Message 235 by Taq
08-11-2017 3:13 PM


Re: the usual silly wrong linear analogy
New mutations produce new phenotypes. New phenotypes are selected for. New mutations produce new phenotypes. New phenotypes are selected for. New mutations produce new phenotypes. New phenotypes are selected for.
IT NEVER STOPS. IT KEEPS GOING

We could argue about how frequently mutations produce new phenotypes -- it's not as often as you are implying -- but that would be off the point. The point is that when the new phenotypes are selected for and form a new population, over time they replace the unselected phenotypes throughout the population and that makes for a loss of genetic diversity in this new population.

Another way to talk about genetic diversity is in terms of heterozygosity. You get increasing homozygosity for the selected traits in a new population that becomes a new variety or species. This is a general trend. At the extreme, as in old fashioned domestic breeding to get a pure breed, your purebred animal will have a great number of fixed loci for the salient traits of the breed.

This is what must also happen in nature though not as cleanly and rapidly. If you are getting migrations of portions of a main population to new territory where they become isolated and inbred over a number of generations. This is a form of selection. You are isolating a small portion of the gene pool of the parent population which produces a new set of gene frequencies from the parent population. The smaller the daughter population the more effect this will have on the development of its new trait picture because the gene frequencies will be more dramatically different from the parent population.

This must be what happens in a ring species. The second species in the ring would start with a relatively small number of individuals from the original species, and over a number of generations in isolation it develops a whole new look from the original. New coloring for the salamander species in California, new plumage and song for the greenish warblers, new markings for the seagulls that ring the Atlantic, and I'm not sure how the chipmunks of the Sierra vary but they too form a ring species around the mountains.

The third species in the ring develops from a small number of individuals from the second, and so on around the ring, each new species of necessity losing the genetic material for earlier phenotypes as new ones become prominent. After a number of such population splits, each losing some genetic material present in the former, the last in the ring should be fairly genetically depleted. Of course in reality there are going to be hybrid zones or continued or resumed gene flow between populations, so it's not going to be this streamlined, but the principle should be recognizable nevertheless.

What happens with a Founder population, one that develops from very very few individuals, is an extreme of what I'm talking about. That's how the cheetah formed, and the elephant seals. It's really just a more drastic way to form a new species though in this fallen world it compromises the health of the animal. In the ideal world God originally made all such new species would be healthy, but I digress.

Founder Effect is just an extreme of what I'm talking about. The more individuals that found a new population the less obvious both the phenotypic changes and the genetic loss will be, but it should still be the trend nevertheless.

Evo thinking has assumed that evolution takes a long time, but in reality it doesn't. This is demonstrated by such examples as the Pod Mrcaru lizards which were discussed here a few years ago, and the Jutland cattle somebody also brought up on that same thread.

Ten lizards, five male and five female, were introduced onto an island and left to their own devices. Thirty years later they were found to have become numerous and to have developed a completely new morphology: a very large head and jaw, and a new diet of much tougher food than the original population ate -- but not because the same food was not present in their new location, just because their laws were now suited to the tougher stuff. This was regarded as showing an unusually high rate of evolution, but it's exactly what I think we should expect. It doesn't take many generations to produce a new species or race or variety starting from a small number of individuals. The number could have been larger and would still have produced some noticeable changes in the total population over thirty years, perhaps not the same changes.

The cattle example as I recall was a case of accidental separation of four different groups from the parent population, each of which developed a brand new strikingly different appearance after only a few years in isolation. That's because the ToE is wrong: evolution does not take a long time, all it takes is the normal sexual recombination of a new set of gene frequencies over whatever number of years needed to blend them all together.

There is no reason to assume mutations had anything to do with these changes, but the processes involved would be the same with or without them. The original alleles would be quite enough to produce the observed changes.

Surely there can be no argument that in these cases there had to have been greately reduced genetic diversity in each new population in relation to the parent population, because that's the inevitable situation with the founding of a new population from a small number of individuals.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 235 by Taq, posted 08-11-2017 3:13 PM Taq has responded

Replies to this message:
 Message 240 by PaulK, posted 08-12-2017 2:56 AM Faith has responded
 Message 273 by Taq, posted 08-14-2017 10:46 AM Faith has responded

    
Faith
Member
Posts: 32715
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 241 of 908 (816847)
08-12-2017 3:27 AM
Reply to: Message 239 by PaulK
08-12-2017 2:37 AM


Re: Faith gets it wrong again
Of course it destroys your assertion that the loss of variation must end evolution.

That can't happen. Anybody who honestly thinks it through should recognize that the loss of genetic diversity brought about by the processes of microevolution that produce new varieties, races and species, has to bring evolution to an end.

However selection is expressed in Dawkins' model is false. Watch the program work, it just produces one variation after another as if it had infinite resources.


This message is a reply to:
 Message 239 by PaulK, posted 08-12-2017 2:37 AM PaulK has responded

Replies to this message:
 Message 242 by Tangle, posted 08-12-2017 3:34 AM Faith has not yet responded
 Message 243 by PaulK, posted 08-12-2017 3:42 AM Faith has not yet responded

    
1
23456
...
15NextFF
Newer Topic | Older Topic
Jump to:


Copyright 2001-2018 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2019