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Author Topic:   WTF is wrong with people
AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


(1)
Message 346 of 457 (708530)
10-10-2013 7:27 PM
Reply to: Message 344 by Faith
10-10-2013 6:43 PM


Re: Environment-driven evolution
Once Natural Selection or any other "mechanism of change" that brings about a new subpopulation kicks in then you have the trend to reduced genetic diversity and it just swallows up your mutations.
At about 2,100,000,000 mutations entering the human genome every year, that would take a whole lot of swallowing.
and this
" Once Natural Selection or any other 'mechanism of change' that brings about a new subpopulation kicks in then you have the trend to reduced genetic diversity"
is just pure bullshit as you have been shown many times.

This message is a reply to:
 Message 344 by Faith, posted 10-10-2013 6:43 PM Faith has replied

Replies to this message:
 Message 364 by Faith, posted 10-11-2013 12:55 PM AZPaul3 has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 347 of 457 (708531)
10-10-2013 7:28 PM
Reply to: Message 345 by AZPaul3
10-10-2013 7:10 PM


Re: Environment-driven evolution
Then you misunderstand what everyone has been trying to tell you for years now. Yes, allele frequency is an agent of change. The different forms of selection are agents of change since they change allele frequency. Mutation of DNA into new alleles is an agent of change since they change allele frequency . Drift is an agent of change since they change allele frequency. .....
In the end, yes, evolution is the change in allele frequency in a population. But there are different mechanisms that cause this frequency change including new alleles.
For cryin out loud I've been saying all this all along!!!!! And I JUST GOT THROUGH SAYING IT AGAIN ABOUT NATURAL SELECTION!!! What I'm adding, or emphasizing, is just that ALL these things bring about POPULATION SPLITS, which is THE FUNDAMENTAL DEFINITIVE way allele frequencies get changed. YES, THROUGH ALL THOSE DIFFERENT MECHANISMS.
Sheesh.

This message is a reply to:
 Message 345 by AZPaul3, posted 10-10-2013 7:10 PM AZPaul3 has replied

Replies to this message:
 Message 348 by Tangle, posted 10-10-2013 7:36 PM Faith has not replied
 Message 349 by AZPaul3, posted 10-10-2013 7:57 PM Faith has replied
 Message 358 by Percy, posted 10-11-2013 8:40 AM Faith has not replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


(2)
Message 348 of 457 (708533)
10-10-2013 7:36 PM
Reply to: Message 347 by Faith
10-10-2013 7:28 PM


Re: Environment-driven evolution
Faith writes:
For cryin out loud I've been saying all this all along!!!!! And I JUST GOT THROUGH SAYING IT AGAIN ABOUT NATURAL SELECTION!!! What I'm adding, or emphasizing, is just that ALL these things bring about POPULATION SPLITS, which is THE FUNDAMENTAL DEFINITIVE way allele frequencies get changed. YES, THROUGH ALL THOSE DIFFERENT MECHANISMS.
Well silly old us. There we were thinking that you didn't believe in evolution when all along it turns out that you accept mutation, genetic drift and natural selection and that isolated populations will change over time as a result of those - and other - mechanisms.
So we have descent with modification by natural selection. And a few more modern bits and pieces too. Congratulations, you're now what you call an "evolutionist."

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 347 by Faith, posted 10-10-2013 7:28 PM Faith has not replied

  
AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


(1)
Message 349 of 457 (708535)
10-10-2013 7:57 PM
Reply to: Message 347 by Faith
10-10-2013 7:28 PM


Re: Environment-driven evolution
What I'm adding, or emphasizing, is just that ALL these things bring about POPULATION SPLITS, which is THE FUNDAMENTAL DEFINITIVE way allele frequencies get changed.
No, Faith. These mechanisms of change operate quite readily in an unsplit population. These add genetic diversity to the population. Genetic diversity will not split a population.
Only reproductive isolation causes a population split. At that point the same old mechanisms of allele frequency change continue more or less just as always. If the initial number of the smaller split population is low then we get the cheetah situation with a higher probability of extinction of that sub-population since new diversity is also low to nonexistent. If the sub-population is not too small then genetic diversity will increase with each new generation. That is what sex and mutation do for a species assuming selection allows the changes.
Edited by AZPaul3, : No reason given.
Edited by AZPaul3, : re-word and re-order
Edited by AZPaul3, : No reason given.

This message is a reply to:
 Message 347 by Faith, posted 10-10-2013 7:28 PM Faith has replied

Replies to this message:
 Message 350 by Faith, posted 10-10-2013 8:49 PM AZPaul3 has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 350 of 457 (708537)
10-10-2013 8:49 PM
Reply to: Message 349 by AZPaul3
10-10-2013 7:57 PM


Re: Environment-driven evolution
No, Faith. These mechanisms of change operate quite readily in an unsplit population.
No, YOU are wrong. All but mutations bring about population splits. Anything that acts as a selector and isolator is a population splitter. All those mechanisms act in that way, only mutations don't. Some population splits can occur WITHIN a larger population TOO, as I've also said a number of times. I believe Drift can be described that way. Whenever a particular allele or set of alleles occurs in higher frequency that does not spread through the entire larger population, THAT's the equivalent of a population split, creating its own reproductively isolated subpopulation within the larger. Natural Selection may also operate that way or it may actually just eliminate nonadaptive alleles and create a brand new population. Migration creates a completely separate population as I've understood the term, a new population that's migrated away from the mother population..
These add genetic diversity to the population.
Far from it. All you are getting is new gene/allele frequencies, and this is due to the fact that you have fewer numbers in both new populations than you did in the original population, and when you have fewer numbers you are not adding genetic diversity, you merely have new allele frequencies to combine in new ways. And Drift may eliminate any low frequency alleles altogether, and so will a subpopulation that is a great deal smaller than the original, and then you definitely have reduced genetic diversity.
Genetic diversity will not split a population.
Of course not, but it will be reduced in any new small population that splits off from it.
Only reproductive isolation causes a population split.
I've been using the terms more or less synonymously myself all along, although some population splits do not bring about complete reproductive isolation. Nevertheless they are roughly equivalent and the result is new allele frequencies and therefore new phenotypes, and very often ALSO a reduction in genetic diversity.
At that point the same old mechanisms of allele frequency change continue more or less just as always. If the initial number of the smaller split population is low then we get the cheetah situation with a higher probability of extinction of that sub-population since new diversity is also low to nonexistent.
Which is also what I've been saying all along. Where have YOU been?
If the sub-population is not too small then genetic diversity will increase with each new generation. That is what sex and mutation do for a species assuming selection allows the changes.
Sex only shuffles alleles, it does not increase genetic diversity. Mutation is the only thing that could possibly increase genetic diversity, assuming reproductive isolation, that is, where there is no gene flow with other populations.
And as I've argued, all this happens a lot faster than the ToE supposed. I think the lizard video time frame of just a few decades is probably quite typical, the long time frames are pure unevidenced theory. And with such short time frames you are not going to get enough mutation to increase diversity by much, AND even if you did, IF you then also get Selection, or Migration or anything else that further splits the population and creates a new variety, then you're back on the track to reduced genetic diversity and the end of evolution for that line of variation no matter how many mutations you have.
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 349 by AZPaul3, posted 10-10-2013 7:57 PM AZPaul3 has replied

Replies to this message:
 Message 351 by AZPaul3, posted 10-10-2013 10:21 PM Faith has replied

  
AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


(1)
Message 351 of 457 (708540)
10-10-2013 10:21 PM
Reply to: Message 350 by Faith
10-10-2013 8:49 PM


Re: Environment-driven evolution
All those mechanisms act in that way, only mutations don't. Some population splits can occur WITHIN a larger population TOO, as I've also said a number of times. I believe Drift can be described that way. Whenever a particular allele or set of alleles occurs in higher frequency that does not spread through the entire larger population, THAT's the equivalent of a population split, creating its own reproductively isolated subpopulation within the larger.
Oh, my lady, how can you get so much wrong in such a short amount of space.
Yes, in massive populations over an extended range the population in the eastern quarter may have an allele frequency quite different than the population in the western quarter. We already know this. Over time the eastern and western populations may diverge to the point of separate identities. But this was not caused because of some intrinsic feature of allele frequency but because of the reproductive isolation of the two populations over a large geographic region.
You gotta think before you speak ... er ... write.
Migration creates a completely separate population as I've understood the term, a new population that's migrated away from the mother population.
Yes, migration often does mean reproductive isolation and a population split and is exactly the same scenario as the split in the east-west population scenario.
These add genetic diversity to the population.
Far from it. All you are getting is new gene/allele frequencies, and this is due to the fact that you have fewer numbers in both new populations than you did in the original population, and when you have fewer numbers you are not adding genetic diversity, you merely have new allele frequencies to combine in new ways.
With the initial populations, yes, the split may reduce the genetic diversity in each population. But, again, think before you speak.
"you are not adding genetic diversity, you merely have new allele frequencies to combine in new ways."
Combining alleles in new ways, in new combinations, with new strengths and weaknesses, is, by definition, an increase in genetic diversity! Now add new alleles via mutation to the combinatorial mix and genetic diversity increases yet again.
At that point the same old mechanisms of allele frequency change continue more or less just as always. If the initial number of the smaller split population is low then we get the cheetah situation with a higher probability of extinction of that sub-population since new diversity is also low to nonexistent.
Which is also what I've been saying all along. Where have YOU been?
Don't get testy, dear. Just repeating for clarification and full understanding. I never said you were wrong about this one small fact.
Sex only shuffles alleles, it does not increase genetic diversity.
Read the literature, Faith. The invention of sex was one of the biggest genetic-diversity mechanisms ever to come along in the history of life on this planet.
And as I've argued, all this happens a lot faster than the ToE supposed. I think the lizard video time frame of just a few decades is probably quite typical, the long time frames are pure unevidenced theory.
First, the mutation rate of 30-50 mutations per individual per generation means the rate of increase in genetic diversity due to mutation is dependant upon the sexual proclivity, ie time to maturity, gestation rate and initial population size (partner availability) of the species in question. In humans this generation creation is about 20 years. Lizards have much faster generation creation.
Second, the strong evidence for evolution in deep time is well known and well documented. You continue to ignore reality to bolster your inner need for your religious fantasy. That's too bad. You are a lovely Lady otherwise, and I am greatly emotionally disturbed by your being so intellectually disturbed.
Edited by AZPaul3, : No reason given.

This message is a reply to:
 Message 350 by Faith, posted 10-10-2013 8:49 PM Faith has replied

Replies to this message:
 Message 368 by Faith, posted 10-11-2013 1:43 PM AZPaul3 has seen this message but not replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(1)
Message 352 of 457 (708544)
10-11-2013 2:23 AM
Reply to: Message 344 by Faith
10-10-2013 6:43 PM


Re: Environment-driven evolution
I hope that you intent to answer my message above Message 341. It seems rather important if you want your argument to be understood.
quote:
Look, people are always saying Darwin has been transcended. (that's when a Creationist is the one quoting Darwin of course.) Mutations for one thing are THE change factor now. Not that Natural Selection has gone away and I've never denied it, ever, in fact I've kept including it as a change factor all along. It's just that many other concepts have entered into the theory since Darwin, and a big one is the population genetics understanding of evolution coming about through change in gene/allele frequencies.
That's a pretty massive misunderstanding right there. Of course we've advanced since Darwin. Science doesn't stand still. And by combining Mendel's genetics with Darwin's theory the New Synthesis (which is no longer new) actually solved a problem that Darwin had no good answer to. But even Darwin knew that he needed a source of new variations for his theory to work, and recognised the appearance of "sports".
quote:
So don't get so uppity about what I know and don't know. I'm emphasizing change in allele frequencies and I've been arguing all along for it as the biggest change factor, caused by population splits alone, and I've ALWAYS included Natural Selection as one of the ways reproductive isolation is brought about, which is THE way change occurs, NS being one version of it, according to my argument.
If you don't like people pointing out that you don't understand the subject of discussion it really is down to you to get that understanding or avoid the subject.
Change in allele frequencies is change, not a cause of change, and population splits in themselves do nothing to cause it.
Natural Selection MAY be a cause of some reproductive isolation (though generally NOT in the case where the population is already isolated by geographical division !). It will only ever be a direct cause of reproductive isolation where breeding between two populations is disadvantageous.
quote:
I've been expecting everybody at least to know that change in allele frequencies is A change factor, and until now NOBODY said uh uh, Selection is the big change factor. Mutations mutations mutations has been the theme song. I could have addressed NS months ago, years ago, if it had been made THE issue as it appears to be now.
THe emphasis on mutations is due to the fact that they are a source of genuinely new variations. This counters your idea that diversity must decrease, the central point of your argument. That other issues are also raised to answer other points that you introduce does nothing to change that.
quote:
And it turns out you all even deny change in allele frequencies as any kind of driving element. You mentioned drift and mutations, PERIOD and treated the very idea of change without those or Selection as IMPOSSIBLE and even DAFT. Percy absolutely denies change without Selection.
This is not MY problem, sorry.
I'm sorry Faith, but if you are unable to distinguish between cause and effect that IS your problems. Natural selection and drift CAUSE changes in allele frequencies. Change in allele frequencies is NOT a "driving element" - it's what the driving elements cause.
[quote] Evolution by descent with modification is STILL the basic plank and that plank is assumed in my argument. Change (modification; new phenotypes) occurs down the generations ("descent"), but I think NS is only one not very typical way it occurs, WHICH I'VE SAID over and over. CHANGE IN ALLELE FREQUENCIES is THE way change occurs, the way modification is brought about, the way new phenotypes are brought about. Natural Selection is one way allele frequencies change because it's one way a new subpopulation is created.
[.quote]
No. Natural selection does not create a new sub-population. Natural selection produces adaptive change within a population. And - like drift - it works faster in a small population. Natural selection is a driving factor in the CHANGE of small populations - but it rarely causes divisions.
quote:
Subpopulations are often smaller than the original population and when they are then we have the trend to decreased genetic diversity that shows that evolution has a stopping point.
It shows nothing of the sort.
quote:
Even if you add in mutations this trend is not affected.
Faith, I asked you to be honest about the limitations of your argument. You replied that it is difficult. But it shouldn't be difficult for you to admit that this is just your opinion. THat you haven't done the work to show that it is true - or even come up with an argument to show that it is true. Te evidence that we have show no sign of your trend being a significant factor over hundreds of millions of years of evolution, including a number of mass extinctions.
It's all been pointed out to you. And even if it hadn't been you should known the difference between what you assume and what you've shown. So be honest and at least admit that mutations will go against your trend and could counter it instead of denying the possibility.
quote:
Once Natural Selection or any other "mechanism of change" that brings about a new subpopulation kicks in then you have the trend to reduced genetic diversity and it juust swallows up your mutations.
Of course it doesn't have to, in fact it's very unlikely that it will. The loss of alleles will slow as more alleles are lost (going to zero when the population is completely uniform). The gain of new alleles is NOT slowed in the same way. And circumstances can favour increase over decrease (large population, weak selective pressures).
So all you have is a rather implausible assumption. That is WHY YOU NEED THE NUMBERS. I really don't see why you can't understand that.

This message is a reply to:
 Message 344 by Faith, posted 10-10-2013 6:43 PM Faith has not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(1)
Message 353 of 457 (708567)
10-11-2013 7:19 AM
Reply to: Message 325 by Tangle
10-10-2013 9:46 AM


Re: Environment-driven evolution
Tangle writes:
I simply mean that both population's genotypes - the mother population and the split population - will change in the normal ways through drift and mutation but they will do so independently of each other.
I think selection must be included. Its effect is far greater and more immediate than drift.
My money though is not on mutation to create the jaw and digestive tract changes - including the ability trap bacteria to break down cellulose - it seems far more likely to be a genetic trait from an earlier population has popped back up because the environment suits it.
Right. Most species have a huge reservoir of variation upon which to draw.
...there needs to be a mechanic for a change which, as we know is drift or mutation and a mechanic to direct the change, which we know is selection.
Your use of the word "mechanic" may be throwing me off, but I think I understand this well enough. I'm not sure Faith would understand this, though, and we can see that she's becoming more and more confused. Incredibly and unbelievably confused, in fact. I can't believe that after a decade here Faith still forgets the definition of evolution (I say "forgets" because sometimes it does seem that she knows the definition), but anyway, for Faith's sake let me take my own stab at describing drift and mutation's role in evolution.
There are two main components to evolution. One of them is descent with modification. It includes allele and gene reshuffling (part of the reproductive process), and it includes mutation. Descent with modification means that offspring are slightly different from their parents.
The other main component of evolution is selection. Selection is imposed upon species by the environment. It controls which individuals are best able to pass on their genes to the next generation, and it is most responsible for changing allele frequency. Drift is simply variation that is insufficiently positive or negative to be operated on by selection.
Selection operating on variation within a population (both inherent variation and new variation from mutation) produces adaptation. This is why when a lizard's diet evolves from mainly insects to mainly vegetation when moved to an island rich in vegetation that we suspect selection at work. Had the lizards somehow adapted to something not on the island we definitely would have suspected something other than selection at work.
--Percy
Edited by Percy, : Grammar.
Edited by Percy, : Typo.

This message is a reply to:
 Message 325 by Tangle, posted 10-10-2013 9:46 AM Tangle has replied

Replies to this message:
 Message 356 by Tangle, posted 10-11-2013 8:15 AM Percy has replied
 Message 360 by NoNukes, posted 10-11-2013 9:15 AM Percy has replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(1)
Message 354 of 457 (708568)
10-11-2013 7:39 AM
Reply to: Message 337 by Faith
10-10-2013 2:50 PM


Re: Environment-driven evolution
Faith writes:
Why the idea that change comes about from changed allele frequencies is daft is beyond me.
That wasn't what Tangle was calling daft. What's daft is your idea that merely isolating a subpopulation will produce changes in allele frequencies sufficient for producing phenotypic change. As has been pointed out to you, if this were the case then we would see it happening in both captive and natural subpopulations over and over and over again, but we do not.
Any randomly selected subpopulation will have allele frequencies that pretty much mirror the general population. They'll just be missing many of the less common alleles, which accounts for the reduction in genetic diversity. In the absence of different selection pressures they'll continue to have allele frequencies that mirror the general population.
But if selection pressures change then the subpopulation will have less variation to draw upon than the general population and will be less well equipped to adapt.
--Percy

This message is a reply to:
 Message 337 by Faith, posted 10-10-2013 2:50 PM Faith has replied

Replies to this message:
 Message 367 by Faith, posted 10-11-2013 1:33 PM Percy has seen this message but not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(1)
Message 355 of 457 (708571)
10-11-2013 8:01 AM
Reply to: Message 340 by Faith
10-10-2013 3:59 PM


Re: Environment-driven evolution
Faith writes:
Why the idea that change comes about from changed allele frequencies is daft is beyond me.
Selection has always been by far the biggest factor controlling allele frequencies in populations.
There may be other hidden assumptions and expectations I need to find out about as well.
There's nothing hidden about selection, Faith. It's right there in the full title of Darwin's book: On the The Origin of Species by Means of Natural Selection, and it's been the most prominent feature of the theory from its beginning right up until today.
The one key fact that emerges from you questioning selection's role in evolution is that if one explains anything to Faith she'll just become more confused. Forgetting the significant role of selection in evolution is like forgetting that light is a key component of seeing.
--Percy

This message is a reply to:
 Message 340 by Faith, posted 10-10-2013 3:59 PM Faith has not replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


Message 356 of 457 (708575)
10-11-2013 8:15 AM
Reply to: Message 353 by Percy
10-11-2013 7:19 AM


Re: Environment-driven evolution
Percy writes:
I think selection must be included. Its effect is far greater and more immediate than drift.
Oh, absolutely. I was just trying to separate the agents than cause change from the agent that directs change once caused because Faith thinks that merely separating a population both causes and directs change.
Well, I think that's what she thinks - she's all over the place.

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 353 by Percy, posted 10-11-2013 7:19 AM Percy has replied

Replies to this message:
 Message 359 by Percy, posted 10-11-2013 8:55 AM Tangle has replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(1)
Message 357 of 457 (708577)
10-11-2013 8:31 AM
Reply to: Message 344 by Faith
10-10-2013 6:43 PM


Re: Environment-driven evolution
Faith writes:
It's just that many other concepts have entered into the theory since Darwin, and a big one is the population genetics understanding of evolution coming about through change in gene/allele frequencies.
Your lack of understanding is causing you to become very confused. When someone defines evolution as changing allele frequencies over time and doesn't mention selection, as they might do when discussing population genetics, it doesn't mean they have a different definition of evolution that downplays selection's role. They're merely assuming the audience already knows the definition of evolution. Population genetics understands that by far the biggest player in changing allele frequencies over time is selection.
Faith, you can't let every occurrence of an incomplete or contextual definition (or even a very poor definition as in the case of the Berkeley site, which you would have recognized had the come to that site with a decent understanding of evolution) lead you astray. First and foremost evolution is descent with modification and natural selection. That will never change.
So don't get so uppity about what I know and don't know.
You're asking people not to become upset and frustrated when your frequent misunderstandings and misinterpretations become a big waste of time. I don't think that's going to happen. I can't believe that after your decade here we still have to explain the key role selection plays in evolution.
Evolution by descent with modification is STILL the basic plank and that plank is assumed in my argument.
You're forgetting selection. Again.
Natural Selection is one way allele frequencies change because it's one way a new subpopulation is created.
And again, selection does not create subpopulations. Since all individuals of a population are subjected to the same selection pressures, just how do you imagine a subpopulation being created by selection?
So once again you have things completely backwards. The way it actually works is that first a subpopulation is formed, then if it is subjected to different selection pressures it will begin to differ from the main population.
Subpopulations are often smaller than the original population and when they are then we have the trend to decreased genetic diversity that shows that evolution has a stopping point. Even if you add in mutations this trend is not affected.
The creation of a subpopulation is an event that reduces genetic diversity, but it only occurs once while the process of mutation occurs over and over and over again with each and every act of reproduction.
Let's say a river changes course, splitting a subpopulation of a 1000 individuals off from a larger population of 1,000,000. That's one single event causing reduced genetic diversity. But every new offspring in the subpopulation will contain a number of mutations, probably somewhere between 10 and 100. Since the subpopulation is not dividing into sub-subpopulations and sub-sub-subpopulations, in other words, since the process that reduces genetic diversity is no longer occurring, just how do you imagine genetic diversity continuing to decline as mutations pour in?
--Percy
Edited by Percy, : Improved clarity.

This message is a reply to:
 Message 344 by Faith, posted 10-10-2013 6:43 PM Faith has not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(1)
Message 358 of 457 (708579)
10-11-2013 8:40 AM
Reply to: Message 347 by Faith
10-10-2013 7:28 PM


Re: Environment-driven evolution
Faith writes:
For cryin out loud I've been saying all this all along!!!!! And I JUST GOT THROUGH SAYING IT AGAIN ABOUT NATURAL SELECTION!!! What I'm adding, or emphasizing, is just that ALL these things bring about POPULATION SPLITS, which is THE FUNDAMENTAL DEFINITIVE way allele frequencies get changed. YES, THROUGH ALL THOSE DIFFERENT MECHANISMS.
Sheesh.
Sheesh, yourself.
The gorilla of evolutionary change is natural selection. Nothing else comes close. If you think otherwise than just imagine a simple bacterial experiment. In one set of petri dishes you provide a variety of different nutrient mixes, in the other set you provide the standard nutrient mix the bacteria are used to. I guarantee you that every single time you run this experiment that the vast majority of change will be in the bacteria with the modified nutrient sources.
I can't believe you can be so wrong about something as obvious as selection. Breeders long ago discovered that the fastest and most effective way to achieve desired change is selection. They use no other approach because no other approach works. It's simple rational thinking and logic, Faith. Use some.
--Percy

This message is a reply to:
 Message 347 by Faith, posted 10-10-2013 7:28 PM Faith has not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 359 of 457 (708582)
10-11-2013 8:55 AM
Reply to: Message 356 by Tangle
10-11-2013 8:15 AM


Re: Environment-driven evolution
Tangle writes:
Oh, absolutely. I was just trying to separate the agents than cause change from the agent that directs change once caused because Faith thinks that merely separating a population both causes and directs change.
Oh, okay. And going back and looking at the message chain again I can see this now, but I'm confident that Faith will interpret your lack of mention of selection in that particular message as an indication that you don't believe selection is important. Incredible, I know, but there it is.
--Percy

This message is a reply to:
 Message 356 by Tangle, posted 10-11-2013 8:15 AM Tangle has replied

Replies to this message:
 Message 366 by Tangle, posted 10-11-2013 1:32 PM Percy has replied

  
NoNukes
Inactive Member


(1)
Message 360 of 457 (708588)
10-11-2013 9:15 AM
Reply to: Message 353 by Percy
10-11-2013 7:19 AM


Re: Environment-driven evolution
I think selection must be included. Its effect is far greater and more immediate than drift.
I think understating the role of drift is to commit an error. Drift explains the ready pool of variation within a population. If in fact, things were arranged so that an immediate mutation was required to deal with selection pressure, I don't believe evolution would be successful.
There are some confused statements regarding evolution present in this discussion, some of which center around this point. It is at least possible that Faith is confused by some of them, although I think the truth has been stated correctly often enough that a more capable person would have understood at least where the disagreement lies.
The truth is that some aspects of the evolution of species are a bit like breeding collies. Nature selection, except in the rarest circumstances, works on already available variation. The difference is that natural selection can only selects for fitness traits while breeders select for all traits of any interest to the breeder. Evolution also includes an element of chance. Sometimes the slow gazelle does get away. Breeding however involves no such probability. The badly spotted collie is immediately separated out.
It is the nature of the selection along with the continuing role of mutation and drift that leads to a completely different end result for breeding collies and evolution. If a collie puppy with kitten ears turns up through a mutation, the breeder discards that puppy from the gene pool, but evolution forces don't do any such thing. In short "blurring" is solely a breeding phenomenon. It is not a problem for actual evolution, and you don't have to be the sharpest knife in the drawer to get that.
Breeding is essentially a dead end because that's what humans ensure happens by culling. But evolution is not the same kind of dead end. And if Faith wants to show that ordinary mutation rates cannot replenish a species after a population split, I expect to see math backed denials. Show me the math. Even some back of the envelop calculations have got to be more convincing than the mere denials from someone who knows diddly squat.
Edited by NoNukes, : Add chance/probability

Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)
I believe that a scientist looking at nonscientific problems is just as dumb as the next guy.
Richard P. Feynman
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 353 by Percy, posted 10-11-2013 7:19 AM Percy has replied

Replies to this message:
 Message 361 by Percy, posted 10-11-2013 9:39 AM NoNukes has replied

  
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