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Author Topic:   Evolution Requires Reduction in Genetic Diversity
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 856 of 1034 (759432)
06-11-2015 11:27 AM
Reply to: Message 847 by mikechell
06-11-2015 7:06 AM


Re: macroevolution not impossible -- it has been observed.
Genetic adaptation IS an accident. It's NOT a "choice". If that "accident" is beneficial, it propagates through successive generations because it HELPS reproduction.
Indeed. Dawkins described evolution as a drunken stagger. It is a two-step feedback response system that is repeated in each generation:
Like walking on first one foot and then the next.
Mutations of hereditary traits have been observed to occur, and thus this aspect of evolution is an observed, known objective fact, rather than an untested hypothesis.
Different mixing of existing hereditary traits (ie Mendelian inheritance patterns) have been observed to occur, and thus this aspect of evolution is an observed, known objective fact, rather than an untested hypothesis.
Natural selection has been observed to occur, along with the observed alteration in the distribution of hereditary traits within breeding populations, and thus this aspect of evolution is an observed, known objective fact, and not an untested hypothesis
Neutral drift has been observed to occur, along with the observed alteration in the distribution of hereditary traits within breeding populations, and thus this aspect of evolution is an observed, known objective fact, and not an untested hypothesis.
Thus many processes of evolution are observed, known objective facts, and not untested hypotheses.
Enjoy

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This message is a reply to:
 Message 847 by mikechell, posted 06-11-2015 7:06 AM mikechell has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 866 of 1034 (759447)
06-11-2015 1:14 PM
Reply to: Message 821 by Faith
06-10-2015 6:52 PM


Re: macroevolution not impossible -- it has been observed.
What sort of "genetic changes" are you talking about that occur "as they adapt to the different habitats"
Some of it is mutation, some of it is developmental effects on the maturation of the zygotes, and some of it is the random pairing of parental genes, one from column dad, one from column mom. Mutations include places where DNA strands are moved from one site to another or where some sections are omitted or where some sections are duplicated.
and what causes these genetic changes?
They are random, in part because replication is an imperfect process and in part because replication can be affected by environmental aspects (heat, chemical, hormonal).
How can adaptation "produce alleles?"
Adaptation is a two fold process the introduction of variation by mutation and selection of those variations that are better able to survive and reproduce:
Adaptation tends to be habitat\ecology specific (survival success) and mating specific (reproduction success). With runaway sexual selection (peacock) you can have remarkable adaptation with no change in habitat\ecology. We do see a degree of sexual selection in humans with mating preferences and race, but not enough to lead to mating isolation.
And how to the alleles "cause genetic isolation?
When selected alleles in one group (beneficial in it's habitat\ecology for survival and reproduction), happen to be incompatible with the selected alleles in the other population (beneficial in their habitat\ecology for survival and reproduction). Differences are not necessarily incompatible, but it can arise when there is no gene flow between the populations during the period of isolation.
And what "gets acquainted?"
Sorry, I meant reacquainted -- when the two populations that have been isolated happen to come back together, and in American natives and European explorers, or the two northern varieties of the Asian Greenish Warbler.
I'm interested in what happens at different population levels and degrees of genetic diversity. There are many levels and degrees between a fairly large daughter population that wouldn't lose a lot of diversity and a very small daughter population which would, and these could occur in a series, one splitting off from the former, all able to interbreed except the ones at the extremes that can happen in ring species. You aren't always getting speciation although you are always getting some degree of reduced genetic diversity as new subpopulations form their 9own unique traits. That's why I have subspecies in mind. Species by definition requires the cessation of interbreeding.
As in the Asian Greenish Warblers, a commonly used term is varietal or variety, as that implies differentiation between the populations but still being the same species. Race is also used, but to a lesser extent (perhaps because of negative connotations from racial discrimination).
But this is purely conceptual. If what I'm saying is true, that species may lack enough genetic diversity to continue to evolve then they can't "give rise to" any further populations as your chart assumes they do.
And in the absence of evidence to the contrary the assumption of continued genetic diversity and replenishment via mutation and selection is reasonable, especially as there IS evidence that this occurs.
Which is the argument everyone has, but as I keep trying to get across, even if you could get sufficient genetic diversity from mutations at a point of genetic depletion, (and if you could the cheetah would have been saved long ago but it's not happening) you'd just be getting scattered new traits within the population and not a new subspecies or species; ...
It's not a process that occurs all in one generation. As we see with the Cheetah the bottleneck was fairly recent (~12,000 years ago), the population that survived was small, the reproduction rate is low, cheetah populations are fairly isolated, meaning less opportunities for new mutations to occur and then work their way into the breeding population.
... the cheetah would have been saved long ago but it's not happening) ...
Or it just hasn't happened yet.
... you'd just be getting scattered new traits within the population and not a new subspecies or species; ...
And the next generation would have a scattering of more new traits, and the next generation would have a few more ... over time if these traits are beneficial to survival or reproduction or neutral to selection they will spread through the population. Thus the new traits build up over time, each generation building on the new traits from the last generation.
But if the species haven't the genetic ability to evolve further there is no more evolution.
It isn't an ability of the species Faith. Mutations occur randomly and there is no known process that prevents it. Mutations occur, and whether they are beneficial\neutral\deleterious depends on the habitat\ecology (survival) and on sexual compatibility (reproductively viable).
Again, you can't get macroevolution if genetic diversity has run out in the process of bringing about speciation.
And again, mutations occur randomly and there is no known process that prevents it. Mutations occur, and whether they are beneficial\neutral\deleterious depends on the habitat\ecology (survival) and on sexual compatibility (reproductively viable).
You can't get enough mutations for that when you've run out of genetic variability, and even if you could they produce scattered traits rather than a species, ...
If you can't get enough in one generation, then you look at two generation, three generations ... 50 generations ... 100 generations ... it is an accumulative process and not an all at once process.
... and to produce a species requires the processes that reduce genetic diversity.
Not necessarily. You can have two populations with the same genetic diversity becoming isolated in different habitats\ecologies. What happens during the accumulation of new traits and their selection in those habitats\ecologies is what determines whether they become different species or not. Sometimes yes, sometimes no.
Curiously, it's your concepts that have no relation to reality. It's all conceptual or hypothetical. You assume you can get evolution ...
Mutations and selection occur, they have been observed. Speciation occurs and it has been observed. That is not conceptual, it is fact. That IS evolution.
... when you have no genetic variability to make it possible, and you think you can build up variability with mutations which can't occur that reliably and in actual fact DON'T occur reliably, ...
Mutations are random, they are not "on demand" or occur for a purpose, but there is no limitation on mutations happening. That produces an endless supply of variations for selection to act on.
Neither does selection lead to any other purpose than the ability of individuals to survive and reproduce, there is no purpose to increase genetic variability or to produce new species, they are just occasional results of evolutionary processes.
... or again the cheetah and other endangered species would not be in danger. THAT's the reality, RAZD. Your clades and youir diagrams are at best hypothetical and most probably pure fiction.
That endangered species are in danger of going extinct does not mean that evolution does not occur. The natural history of organisms shows that over 99% of species go extinct. That is part of the selection process, occurring at the species level rather than the individual level. You can think of every breeding population as an "individual" species that evolves to increase it's ability to survive, and the "individual" species that are best at survival will supplant those that are less viable.
Evolution won't stop or the world come to an end if the cheetah and other endangered species perish and become extinct, rather there will be species that survive and there will be new species that develop from those living species, as has occurred throughout the natural history of life on earth.
Evolution does not exist to preserve species.
90% of what is offered as "reality" of evolution isn't reality at all, it's purely conceptual, and yet dissertations and websites and debate posts go on and on with these definitional sallies as if they did represent reality. Amazing really.
Because it doesn't do what you think it should do is no reason to think it is conceptual\fiction\etc, Faith, rather it is your narrow misunderstanding\expectations that are what fail.
Enjoy

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This message is a reply to:
 Message 821 by Faith, posted 06-10-2015 6:52 PM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 946 of 1034 (759930)
06-16-2015 9:08 AM
Reply to: Message 886 by Faith
06-12-2015 2:22 PM


recovery
Yes, which is what I've said in earlier posts.
Interesting thought to ponder.
So the question to you would be: do you think humans have reached the end of the road if they have made these varieties but have not made a new species?
Well, I'd go with genetic drift except I keep finding out there seems to be some way I'm not getting genetic drift. I can't make sense out of the definition "random sampling." The best I can do with it is random selection which implies a random change in the look of a population over time in the direction of a homogeneous subpopulation within the population. Best I can do with the concept. But if it's anywhere in the ballpark then it's one of those "subtractive" processes like a population split that I keep saying can eventually form new races or subspecies and does so by losing alleles for traits other than those that are coming to characterize the new subpopulation.
I think you may be making more of it than is necessary.
Genetic drift doesn't care about how a species looks, survives or mates, etc. Think of a population and then have half that village population killed by a volcanic eruption: those that survive do so because they were not there at the time, not by any special trait of their own compared to those that perish. It's like a lottery with some winners and some losers.
Those that survive are the parents of the next generation. What alleles they have would not confer an advantage to survive another eruption.
So I'd agree that the changes aren't due to any selection pressure on the traits themselves, but due to a random favoring of some traits. ...
I would not say "favoring" as that implies some intrinsic value to the survivors compared to the victims that doesn't exist. Consider everyone flips a coin and the heads then form a subpopulation and the tails form a second subpopulation -- the mix of alleles available in each population is a purely random distribution of those in the parent population, based only on what the individuals that got heads had and what the individuals that got tails had.
... But I think you are overlooking the fact that the initial dividing into small bands as they spread out in itself will bring about new allele frequencies that would already affect the look of the band over time with or without additional genetic drift.
But that IS genetic drift -- the "small bands" would not necessarily have the allele distribution of the parent population, but whatever alleles they have become the pool of alleles for their descendants.
How is that selective pressure "demonstrated" as you claim it is though? I don't see any need for selective pressure at all. ...
Perhaps a misunderstanding -- I said that there was no apparent selective pressure.
... Why wouldn't the new allele frequencies created by the initial formation of the band of migrants be enough to explain it?
Same old alleles different frequencies, still not enough to be that different from the parent population to account for the world wide variation seen. Changes would be due to mutations and genetic drift, so that things like skin color and eye color and hair color and hair curliness\straightness etc would vary from one population to the other. These mutations, while not necessarily selected do still mean that the mutations can be tracked from population to population, and from that analysis determine the general paths of migration of the exploratory populations.
The Human Journey: Migration Routes
Yes, like the finches' beaks are adapted to the foods they eat, like that large-headed lizard has adapted to a particular food its stronger jaws can handle, and so on. But the question I keep raising is how you know the creature genetically changed to adapt to the environment when striking changes can occur simply from the new allele frequencies caused by an isolated small population? ...
Except when they exceed the range provided by the previous alleles, and when genetic analysis shows mutations at specific locations: this is increasingly being done, and the evidence to date has been that mutations make new alleles (modify old ones) rather than it just being a selection of existing alleles.
... In that case the creature would simply find the appropriate food or other accommodation in the environment and adapt simply by using the characteristic it already has for the task it's best suited for ...
Which is the same in the case of mutations, the only difference is that mutated alleles have the potential to be beneficial in ecologies that the old ones have less advantage in. The black pocket mice for example - being black by mutation they could then take advantage of the lava beds where black was beneficial compared to tan.
... One thing that makes me think this is that even on different islands the environments aren't different enough to force a genetic change. ...
In this you would be wrong. The ecologies of the different Galapagos islands varies from lush to arid (wiki):
quote:
The islands are famed for their vast number of endemic species and were studied by Charles Darwin during the voyage of the Beagle. ...
Weather changes as altitude increases in the large islands. Temperature decreases gradually with altitude, while precipitation increases due to the condensation of moisture in clouds on the slopes. There is a large range in precipitation from one place to another, not only with altitude, but also depending on the location of the islands, and also with the seasons.
On the larger islands, the pattern of generally wet highlands and drier lowlands impacts the flora. The vegetation in the highlands tends to be green and lush, with tropical woodland in places. The lowland areas tend to have arid and semi-arid vegetation, with many thorny shrubs and cacti, and almost bare volcanic rock elsewhere.
The differences between islands has caused the tortoises, finches and other species (plant and animal) to evolve in different ways,
... Some change over generations probably as the subspecies continues to prefer its food or other qualities of its niche, but all toward elaborating the main characteristic that was already brought out by the new alleles frequencies due only to the population split.
Well that is basically how selection and adaptation works - organisms evolve to take advantage of the opportunities provided by their traits and their ecology, and different populations in different ecologies become differentiated by different adaptations. But there is not much variation available from just inherited alleles, so without new alleles from mutations there would be a coalescing of genotype\phenotype into a stasis population rather rapidly (a generation or two) on an isolated island with a small population.
In most cases there would already be enough variability for a great range of changes and adaptations in any of the small populations we've been talking about. Mutation is hardly ever needed for adaptations. ...
Your claim, no evidence that this is the case. The smaller the population the smaller the gene pool of possible variations on alleles you can have, and the more you need mutations to have variation. Your hypothesis seems to run into itself: first you claim a small population reduces the available alleles dramatically and this brings out rare alleles to cause differentiation, then you claim there is enough allele variation "for a great range of changes" ... which requires a lot of alleles. Or mutations.
... And again I go back to the situations where a handy mutation or set of mutations would save a genetically endangered species like the cheetah and it simply doesn't happen ...
Except that mutation does not occur on demand or in response to any need of any organism. You really should know this by now, with the hundreds of times you must have been told by now.
However, when species do recover from the brink of extinction, it is not through the loss of alleles -- that is what took them to the brink -- but through new random mutations that happened to provide a benefit. In other words, species that have recovered disprove your hypothesis. So rather than species on the endangered list (of which the Cheetah is an extreme example) we should be looking at species that have recovered from being endangered:
Humpback Whales No Longer Endangered - Nature
'Teddy bear' no longer endangered
Gray Wolf no longer endangered? - American News
First Fish That’s No Longer Endangered: Freshwater Species of the Week
and of course we have the History of the Bald Eagle
... and yet this idea that mutation is the source of new genetic material to widen a creature's range of possibilities is always included in these scenarios, clung to as if it were reality.
So tell me Faith, how did species that were endangered due to low numbers of alleles available to the breeding population -- your end scenario for species due to continual loss of alleles as they form species and subspecies and varieties ... -- how do they recover? Where does the genetic material, the alleles, come from to enable a species to recover?
Interested people want to know.
Enjoy

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This message is a reply to:
 Message 886 by Faith, posted 06-12-2015 2:22 PM Faith has replied

Replies to this message:
 Message 947 by jar, posted 06-16-2015 9:15 AM RAZD has replied
 Message 954 by Faith, posted 06-16-2015 10:33 AM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 961 of 1034 (759983)
06-16-2015 1:27 PM
Reply to: Message 947 by jar
06-16-2015 9:15 AM


Re: let them drink milk
Would lactose tolerance be a clear example of a mutation that increased genetic diversity and can be shown to actually be beneficial?
Would sickle cell anemia be a clear example of a mutation that increased genetic diversity and can be shown to actually be beneficial?
Indeed it would show diversity. The question to faith was not that there were no changes in the different populations, but whether it was insufficient to cause speciation and would that mean that we have used up the available diversity to enable speciation -- her argument applied to humans.
There was no apparent pressure to cause speciation that I can see at this time.
Enjoy

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This message is a reply to:
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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 989 of 1034 (769811)
09-25-2015 9:02 AM
Reply to: Message 954 by Faith
06-16-2015 10:33 AM


revived thread
I'm reviving this thread because a lot of what Faith is saying on the Evolution. We Have The Fossils. We Win. thread is just a duplication of what is here, and I'm going to say a bunch of things here to refer to rather than clog that thread up.
So the question to you would be: do you think humans have reached the end of the road if they have made these varieties but have not made a new species?
The end of the road isn't reached until all genetic possibilities have been exhausted. Human beings have a lot of genetic diversity left as far as I can see.
And obviously we are nowhere near the end of the road when species keep appearing.
Genetic drift doesn't care about how a species looks, survives or mates, etc.
It is SO unnecessary and confusing and a waste of time to say such things.
Sorry, but it is necessary to continually point out when terms are misused or misunderstood.
Those that survive are the parents of the next generation. What alleles they have would not confer an advantage to survive another eruption.
That is in many ways quite similar to the population splits I've been talking about, being a random selection of alleles without any regard to fitness, except all the genetic stuff survives rather than dying as in drift.
You still sound confused. Or is it just poorly worded: all the "genetic stuff" dies?
I would not say "favoring" as that implies some intrinsic value to the survivors compared to the victims that doesn't exist.
The word "random" is supposed to take care of that implication. Could say "selection" again but that has the same implication. I can't think of a word for the phenomenon that wouldn't have that implication.
Isn't that what I said? I understand the process, what is apparently needed as a more neutral term and I can't come up with one.
Random distribution.
... Why wouldn't the new allele frequencies created by the initial formation of the band of migrants be enough to explain it?
Same old alleles different frequencies, still not enough to be that different from the parent population to account for the world wide variation seen.
I'm absolutely certain it is, just as you all think not, and there really isn't any proof one way or the other. You imagine mutations making the big differences, where's the evidence?
A different distribution of alleles is sufficient to form a different variety but not a new species that is genetically incompatible -- the evidence is that they were compatible in the parent population.
You have to have new alleles not in the parent population for genetic incompatibility to occur.
Changes would be due to mutations and genetic drift, so that things like skin color and eye color and hair color and hair curliness\straightness etc would vary from one population to the other.
All that is built into the human genome, new traits emerging when new allele frequencies favor it.
Except that it isn't. You can't get blue eyes in a population that does not have blue eye alleles by dividing that population into smaller populations. But I can get blue eyes in a population that does not have blue eye alleles by mutation.
These mutations, while not necessarily selected do still mean that the mutations can be tracked from population to population, and from that analysis determine the general paths of migration of the exploratory populations.
What's being tracked is built-in allelic possibilities, called mutations from the ToE belief in mutations.
Not up to looking at a link right now. (The Human Journey: Migration Routes )
If they were built-in then the distribution analysis would not work.
What evidence? The evidence is that mutations accomplish very little of use to any organism. ... There is NO evidence that mutations are the source of healthy alleles, some flukes where their errors manage to do something useful, but very rare flukes.
The black pocket mice for example - being black by mutation they could then take advantage of the lava beds where black was beneficial compared to tan.
That's the only example anyone can come up with. ...
Show me the evidence! WHAT you HAVE evidence? Anyone could come up with THAT, but it's ONLY ONE!
I mean really, Faith. One piece of evidence is enough to show that it has happened. Biologists don't expect to find evidence like this often, but they do expect mutations to occur because we know they occur. More often than is necessary.
... Raises some questions about how mutations manage to show up for the occasion.
What occasion? Mice living beside volcanic rock for thousands of years before a mutation occurs that allows some mice to survive within the lava fields is an "occasion"??? Really? No, it is a random mutation that occurs and the mice with the mutation were able to take advantage of an ecology the parent population could not use.
On the other hand, if the allele were "built-in" to the genome then there is no reason to wait for it to occur, mice would move into the lava fields and presto chango the trait would "emerge" ...
Which doesn't explain why two different populations have two different mutations.
Yes your "hypothesis" has been refuted.

..... enough for now. As anyone can see it is the same argument being pushed on the other thread, and it would be better to discuss it here.
Enjoy

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This message is a reply to:
 Message 954 by Faith, posted 06-16-2015 10:33 AM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 991 of 1034 (769846)
09-25-2015 2:03 PM
Reply to: Message 986 by Faith
06-25-2015 7:42 AM


From "We have the fossils" thread
From Evolution. We Have The Fossils. We Win. Message 230 Faith says:
The dog breeds change AS A WHOLE, all parts at once, all the bones changing to conform to the overall design of the breed while still articulating according to the Basic Dog Template as it were.
Dead wrong. Every mutt mixture of breeds and half breeds and feral wild dog proves you are wrong. That would be creationist fantasy transformation, certainly not evolution. Every breeder will tell you that you are wrong.
I suspect that you think I'm wrong about something I didn't say, but let me expand a bit. When a breed is being developed, a particular trait or set of traits may be selected but what you get is the overall change I'm talking about: you don't get a bulldog head and legs with a greyhound torso, or a Chihuahua head on a Great Dane body, even if none of those body parts are selected. What you get is an overall proportional structure that goes with the selected traits. It appears that DNA does its thing within the general template or design of the species and not just by piecemeal changes of particular traits. This is perhaps more mysterious and even divine than anything else about how DNA operates.
But you are clearly not in a mood to pursue this topic and there's way too much discord between our views to spend more time on it right now. I don't want to say I'm leaving the thread because as usual I don't know if I will, but I think I should because everything I need to say I've said and I'll just get worn out trying to answer a million objections. We'll see how it goes.
Again you have made a trivially true but irrelevant comment: all organisms are "complete" formed from their particular mix of DNA. Not one organism isn't "complete" ...
... but you also do not get a "complete" change of the whole offspring from the parent, you don't get a bulldog born "complete" from a wolf, which is what it looks like you said (" all parts at once, all the bones changing ... ").
... you don't get a bulldog head and legs with a greyhound torso, or a Chihuahua head on a Great Dane body, even if none of those body parts are selected. ...
Correct, you do not get a chimera, what you get is a mixture of traits from the parents and from mutations. If those parents are different breeds you get a mosaic of traits. But you do not as a rule get a completely new breed in one generation -- it is a mutt at this point. You get part of the new breed, and build on that for the next generation until you reach the desired goal.
... What you get is an overall proportional structure that goes with the selected traits. ...
Again a mundanely true but pointless comment: the offspring will be a complete organism with a "proportional structure" that goes with that particular organism.
What it won't have necessarily is the same proportions as the parent or the end result. There will be intermediate stages with intermediate distributions of structural proportions until the final result is achieved.
... It appears that DNA does its thing within the general template or design of the species and not just by piecemeal changes of particular traits. ...
And again it seems you have it precisely backwards. Evolution works by piecemeal changes that are selected and built on to make the next round of changes in the next generation, that there is no template or design for any new species that is being formed.
... This is perhaps more mysterious and even divine than anything else about how DNA operates.
Or you just don't understand genetics.
But you are clearly not in a mood to pursue this topic and there's way too much discord between our views to spend more time on it right now. I don't want to say I'm leaving the thread because as usual I don't know if I will, but I think I should because everything I need to say I've said and I'll just get worn out trying to answer a million objections. We'll see how it goes.
THIS is YOUR thread to burble on as much as you want to.
Enjoy
Edited by RAZD, : .

we are limited in our ability to understand
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This message is a reply to:
 Message 986 by Faith, posted 06-25-2015 7:42 AM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 992 of 1034 (769890)
09-26-2015 11:16 AM
Reply to: Message 986 by Faith
06-25-2015 7:42 AM


Also from "We have the Fossils" thread
Reply to Faith on Evolution. We Have The Fossils. We Win., Message 233
Not only does genetics not work incrementally, ...
Except we know this is false.
... nor make such just-so changes as those needed to get from the reptilian to the mammalian ear bones ...
As evidenced by the many intermediate fossils that are in the spatial/temporal matrix at the right time and in the right place ...
... there is no need to change the reptilian ear, it works just fine. Nature has no reason to make a mammalian ear out of it -- that is, there is no selection pressure involved. No need to make a mammal out of a reptile at all. So why would there be any changes in that direction?
Evolution does not work on "need" and you know this (or should by now). It works in incremental steps of improvement built on improvement -- better hearing improves the likelihood of survival, so an ear that hears better is selected over one that doesn't.
Just as occurred for eyes and other senses.
ABE: Oh and another thing I meant to include: the basic body structure of an animal is apparently hard-wired into the genome, and so are necessary features like ear design for pete's sake. ...
And this is you making stuff up that has nothing to do with real genetics.
Stuff that we know is wrong.
... The ear structure is just not going to change and neither is the basic reptile body structure. ...
And we know that that is wrong too.
... Genetics varies things like size and shape, whilekeeping the basic body design, fur, or scales in the case of reptiles? color etc. You always get a reptile. You always get a bear, though a small black one or a huge brown one. You always get a dog or a cat. The basic template is in the genome. Huge variations yes but it's always a dog a cat a reptile a bear or whatnot. ...
Standard creationist PRATTle. You've been told how cladistics shows descent from a parent population will always be a member of that parent clade. The formation of nested hierarchies is what shows that evolution explains the diversity of life.
All mammals have the "basic body design" of the common mammalian clade ancestor population, Huge variations yes but it's always a mammal ...
... which has the "basic body design" of the common tetrapod clade ancestor population. Huge variations yes but it's always a tetrapod ...
Random variation is what genetics actually does when there is no selection pressure. It's the most common way varieties and races form in nature. ...
Genetic drift also occurs when there is selection pressure, on traits that are not being selected, but may be taken along for the ride with the gene under selection.
... It's the most common way varieties and races form in nature. ...
It is one of the common ways varieties form. Another is via selection.
... New finch beaks. No reason for it, no selection pressure, it's just a variation possible in the genome and when that genetic option becomes more frequent in a population that is reproductively isolated, the finch gets a new beak. Then it chooses a different food that the new beak can handle.
Which we know is precisely backwards of how it actually happens.
But then you've got those millions of years in there to make this reptile mammal thing happen. You'd only need those millions of years ...
And we know this is false, both in the fact that the evidence shows that the earth IS very very very old, and in the fact that it isn't a matter of "needing" it to be old. That is more creationist PRATTLe.
... You'd only need those millions of years if you kept getting mistakes, unfunctioning ears. Lotta deaf reptile babies then. I guess they just died out or why didn't they adapt to their deafness? ...
Except that the intermediate fossils show there was a fully functional ear through the whole passage of transition. So again you are wrong about what the fossils show and about how evolution actually works ...
... It would of course take time to come up with variations that maintain the necessary relation between the bones for a functioning ear. ...
And we know that each generation would have functioning ears because evolution works by small incremental changes that alter elements but maintain function. Just as the jaw continued to function as it transitioned from the non-mammalian amniote jaw through a phase that had two jaw joints and then to the mammalian jaw.
... But there's no reason for that to happen even in a billion years. This isn't anything like how breeds form, ...
It is precisely how breeds form, because it is how evolution works, gradual modifications from generation to generation within the breeding population:
(1) The process of evolution involves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities for growth, development, survival and reproductive success in changing or different habitats.
Notice how this applies to dog breeds, finch beaks and yes, even therapsid jaws and ears.
... this IS macroevolution and it's impossible.
Except that is impossible because it ISN'T macroevolution, just more creationist PRATTle.
In the biological fields in general and in the field of evolution in particular, macroevolution is defined as process of forming a nested hierarchy by descent of new species from common ancestor populations, via the combination of anagenesis and cladogenesis, and resulting in an increase in the diversity of life. This is often confusing, especially to creationists, because there is no additional mechanism of evolution involved, rather this is just the result of looking at evolution over many generations and within different ecologies.
The process of anagenesis, with the accumulation of changes over many generations, is an observed, known objective fact, and not an untested hypothesis.
The process of cladogenesis, with the subsequent formation of a branching nested genealogy of descent from common ancestor populations is an observed, known objective fact, and not an untested hypothesis.
This means that the basic processes of "macroevolution" are observed, known objective facts, and not untested hypothesies, even if major groups of species are not observed forming (which would take many many generations), the processes are known, and thus they are by definition possible.
The problem I'm trying to highlight here is that discussions of fossil evolution completely ignore what genetics actually does. Evo theory just goes on and on about how such and such changes occurred over those millions of years without knowing if it is even possible, and in reality it's just not.
And curiously, the problem you are actually highlighting is that ignorance of evolution leads to false conclusions not based on facts or evidence, but pure imagination, with all the assurance of Dunning-Kruger effect ignorance.
When every premise you use is wrong, the conclusions are invariably invalid.
Garbage in garbage out.
Enjoy

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This message is a reply to:
 Message 986 by Faith, posted 06-25-2015 7:42 AM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 1001 of 1034 (770045)
09-28-2015 3:27 PM
Reply to: Message 995 by Faith
09-28-2015 12:54 PM


Re: Population Genetics - Faith's errors continue
The first error is that population genetics does not describe phenotypic changes. It describes how alleles change in frequency.
Yes, and the phenotypes that emerge come from the greater frequencies.
No, the change in allele frequency is due to the different phenotypes having different levels of success in surviving and breeding. Those phenotypes are already in the population.
The second error is that population genetics DOS work incrementally over generations. (Indeed, a generation would be a 'round of population genetics')
Sticking with the one and only example I focus on, ...
Arbitrarily chosen because it is the only one that fits your concept?
... that of a reproductively isolated daughter population formed from a relatively small number of individuals, ...
Or what is known as the Founder Effect
quote:
In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. It was first fully outlined by Ernst Mayr in 1942,[1] using existing theoretical work by those such as Sewall Wright.[2] As a result of the loss of genetic variation, the new population may be distinctively different, both genotypically and phenotypically, from the parent population from which it is derived. In extreme cases, the founder effect is thought to lead to the speciation and subsequent evolution of new species.
And if it is successful, this would lead to new traits being selected from available mutations that occur in that population, which would separate it further from the parent population as it becomes a new species. And
quote:
The founder effect is a special case of genetic drift, occurring when a small group in a population splinters off from the original population and forms a new one. The new colony may have less genetic variation than the original population, and through the random sampling of alleles during reproduction of subsequent generations, continue rapidly towards fixation. This consequence of inbreeding makes the colony more vulnerable to extinction.
So this leads to fixation of some existing alleles in the population, and this becomes a base for further evolution. And
quote:
The variation in gene frequency between the original population and colony may also trigger the two groups to diverge significantly over the course of many generations. As the variance, or genetic distance, increases, the two separated populations may become distinctively different, both genetically and phenotypically, although not only genetic drift but also natural selection, gene flow and mutation will all contribute to this divergence. ...
MAY ... over the course of many generations ... become distinctively different ... but also natural selection, gene flow and mutation will all contribute to this divergence. ... so it isn't guaranteed to happen, and when it does it will be through many standard evolutionary processes.
The founding event is not the end of the story, but rather a new beginning.
... what happens in the first few generations is the emergence of a number of different phenotypes in different individuals due to the new gene frequencies, and after whatever number of generations of inbreeding it takes to mix all the genetic types, the population as a whole acquires a new phenotypic look. ...
It's not quite correct to say the "population ... acquires a new phenotypic look" because that is a misuse of the word phenotype. The proper word is Phenome:
quote:
Although a phenotype is the ensemble of observable characteristics displayed by an organism, the word phenome is sometimes used to refer to a collection of traits, while the simultaneous study of such a collection is referred to as phenomics.
Similar to "genome" for a population. The population acquires a new mix of different phenotypes compared to the parent population, and this mix constitutes the phonome of that population.
... Where's the incremental development?
In those intermediate generations. As different alleles sort out and get fixed in the population from generation to generation.
Of course not just the original founding traits will be mixed but any new traits that arise by mutation during this period, and the new traits will have less survival pressure in a small population as the population tries to expand into their ecology.
The rate of fixed new traits/mutations in a population after an extinction event has been shown to increase rapidly after the event and then slow down as the ecological niches become filled. See forams:
quote:
As revealed by the ancient record left by the foram family, the story of recovery after extinction is every bit as busy and colorful as some scientists have long suspected.
"What we've found suggests that the rate of speciation increases dramatically in a biological vacuum," Parker said. " ...
So the rate of increasing diversity is quicker in a vacuum than in a filled ecosystem.
The third error is - as usual - to exclude the role of mutation
That's because, as I've explained so many times, the source of alleles has nothing to do with the processes that reduce genetic diversity.
Indeed, it negates it.
I found this interesting discussion from a dog-breeding site / They discuss many problems connected with breeding programs, and refer to natural populations for comparison from time to time. The only mention of mutations is in the paragraph about Hardy-Weinberg stability of large populations in which mutations are specifically excluded from the discussion. They discuss all sorts of genetic processes without mutation entering in at all.
...in limited, genetically isolated populations such as CKC breeds a certain amount of genetic diversity is lost with each reproductive event, through the action of genetic drift, inbreeding and artificial selection,
The article is concerned with the problems of breeders and the only real description of natural populations is that very large stable sort of population. They don't discuss the examples I keep focusing on, where active evolution is going on and genetic diversity is consequently being lost from subspecies to subspecies or race to race. But what they say about breeding makes it clear that what they are battling is the same tendency: the reduction in genetic diversity due to the development of a particular phenotypic expression.
That really ought to be pretty good support for what I've been arguing.
Or not, because their interest is in the populations not changing ... perhaps because their interest is in imposing artificial stasis on the breeds once they have been developed ... new pups are inspected and ones that don't meet spec are discarded, which would artificially remove all new traits\mutations from the breeding population, a totally artificial circumstance with no relation to founder populations or any other natural situation.
Might as well answer JAR here too:
But yet again, Faith has NEVER provided the evidence to support "genetic depletion" (whatever that actually means) or explain why genetics shows that folk living at the same time as Adam and even thousands of years before Adam show pretty much the same genetic signature as folk living today or why there is no evidence of the genetic depletion that had to have occurred if either of the Biblical Floods had actually happened and not been just fantasy.
I've many times given the evidence of the effect of the One Flood bottleneck which is the 7% homozygosity in the human genome. It's a reduction in genetic diversity from what had to have been the former more heterozygous condition, though not yet genetic depletion, which comes with extreme homozygosity.
So it was 7% before and 7% after this purported flood event, except that this should also show up in ALL animal populations, to an even higher degree in those "kinds" that only had two on the ark. There is no such genetic signature of a universal bottleneck event.
So no, you have not answered Jars question. You have not presented any evidence of a sudden decrease in the genetic diversity of humans or a single animal, and curiously science moves on evidence not hyperbolic imagination.
He has a thread on this problem for YECs ... perhaps you should take this argument to that thread ... No genetic bottleneck proves no global flood ...
The dog breeding article mentions the problems connected with homozygosity.
Again, dog breeds are artificial bottlenecked populations that are continually trimmed of new traits and mutations.
Enjoy

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This message is a reply to:
 Message 995 by Faith, posted 09-28-2015 12:54 PM Faith has replied

Replies to this message:
 Message 1002 by Faith, posted 09-28-2015 6:44 PM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 1003 of 1034 (770055)
09-28-2015 9:27 PM
Reply to: Message 1002 by Faith
09-28-2015 6:44 PM


Re: Population Genetics - Faith's errors continue
No, the change in allele frequency is due to the different phenotypes having different levels of success in surviving and breeding. Those phenotypes are already in the population.
Change in allele frequency most obviously occurs with the formation of a new isolated population by a relatively small number of individuals. This is the classic view. ...
Curiously, I was pointing out that what you said in Message 995 ("Yes, and the phenotypes that emerge come from the greater frequencies.") was somewhat backwards. The founding phenotypes were those already in the founding population at the time of the founding event, and it is the phenome formed by all those founding individual phenotypes that formed the pool of alleles\genes\traits for that founding populations next generation, the founding phenotypes did not emerge from those alleles.
Perhaps you weren't being clear: following generations certainly would mix those alleles around, but whether that would necessarily create new phenotypes compared to the parent population is not clear. They were all available in both populations.
You DO however get new alleles from mutations, and new mutations can have a higher success rate in small populations, particularly if it is a new open ecology with lots of opportunities, and THAT can certainly (virtually guaranteed to) lead to new phenotypes.
Additionally, a small (developing) population in a new ecology will have different selection pressures than the (mature) parent population had, and this will result in different phenotype selection, which could also cause further drift.
... population splits are THE known cause of changes in gene/allele frequencies. ...
They are A known cause and it is ALSO known that population splits may NOT necessarily result in changes in gene/allele frequencies. You are once again cherry-picking bits and parts that fit your fantasy and ignore the rest.
Mutations and selection are another means of altering the frequencies. Drift does not cause the other processes to suddenly cease. Each generation has new mutations (genome change), each generation undergoes selection for survival and reproductive success (phenome change).
... It is that change that gives rise to new phenotypes in the new population that didn't exist in the parent population, ...
Do you have evidence of such new phenotype where you can guarantee that it is not due to mutation and selection?
Each new generation has new mutations, and when a small population exhibits population growth, that is evidence that selection pressure would be low, meaning more new mutations survive than in a mature population. Again, as pointed out in Message 1001, this has actually been observed to occur.
... Evolution, in a word. Of the micro sort of course.
Indeed:
(1) The process of evolution involves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities for growth, development, survival and reproductive success in changing or different habitats.
Mutations and selection and drift all cause evolution.
... It is that change that gives rise to new phenotypes in the new population that didn't exist in the parent population, that eventually over generations of inbreeding create a new phenotypic appearance in the new population that differentiates it from the parent population. ...
Let me fix that for you:
... It is the change in allele frequencies due to the founder effect plus new mutations not in the parent population and different selection pressures that gives rise to new phenotypes in the new population that didn't exist in the parent population, that eventually over generations of breeding creates a new phenome for the new population that differentiates it from the parent population phenome.
There is no reason that a mixture of alleles that are identical to alleles existing in the parent population will magically create a suddenly new phenotype that never existed in the parent population. With the shift in alleles available in a population due to a founding event being different also means that the phenotypes in that population will have different frequencies. It is with the addition of mutations that you get new traits and it is with the change in selection pressures that you get new phenotypes.
It's the example that demonstrates evolution in action. ...
It's is one of many examples that demonstrate evolution in action.
... A large stable population that isn't evolving (see breeder article if you doubt there is such a thing) doesn't demonstrate what happens during active evolution. ...
Large stable populations exist in stable ecologies, where selection is relatively constant, towards the population average, ie - for stassis.
Breeder selection to remove any change from the breed population is intentional to guarantee the desired goal of population stassis.
This doesn't mean evolution is not active, it is very active, with high pressure to maintain successful phenotypes rather than to create new ones.
... Active evolution that produces new phenotypes doesn't happen without reduced genetic diversity. ...
Wrong. Evolution that produces new phenotypes doesn't happen without low selection pressure. High selection pressure reduces genetic diversity (which is what maintains stable populations in stable ecologies).
... Reduced genetic diversity is the inevitable TREND of evolution. ...
Still wrong, and repeating doesn't change that. Again, you ignore mutations, because it is your fantasy, not for any reason based on actual evidence.
What's amusing is that you focus on a situation which can result in high selection of new mutations compared to a large stable population as your theater stage to claim genetic diversity is reduced.
... At the extremes it becomes genetic depletion. The extremes define the boundary of a species beyond which evolution is impossible for lack of genetic fuel. ...
Which is caused by high selection pressure, such as habitat destruction, overhunting, disease, etc etc etc. and which is why there are more extinct species than living species.
You would think that this steady reduction in genetic diversity that you claim would result in more later species being challenged and robust ancestral populations that did not go extinct. Could you have it backwards again?
... extremes can be avoided in breeding by careful attention to maintaining heterozygosity, as the dog breeding article points out. The same article says that nature seems to work to maintain heterozygosity as well, it being the most healthy state of a population. ...
In large stable populations living in stable ecologies. However this magical aspect of nature did not prevent all those extinct species from surviving, so I kind of get a feeling that it is not really representative of how biology actually works in wild systems.
... But when new populations arise from splits you start to see the effect I'm talking about: active evolution, the production of new varieties, is always accompanied by reduced genetic diversity.
Let me fix that for you:
But when new populations arise from splits you start to see the effect I'm talking about: active evolution, the production of new varieties, is always accompanied by low selection pressure, with population growth allowing more new mutations to spread through the population.
Mutation merely supplies alleles (according to current ToE anyway), but alleles are what get reduced by the evolutionary processes. Mutation therefore does nothing to prevent reduced genetic diversity.
Take an empty plastic jug and put a small hole in the bottom. Now place it in the sink and run water into it. At low levels of flow from the tap the level in the jug will stabilize at a low level. With higher rates of flow the level will stabilize at a higher level. Is it possible for the rate of flow to be so high that it overflows the jug? Is it possible for the rate to be so low that no water remains in the jug? The water from the tap represents new mutations, the hole represents selection (the size of the hole represents the amount of selection pressure), and the amount of water in the jug represents the genetic diversity.
Whether or not more alleles are removed by selection than are provided by mutation depends on selection pressure.
Again you assume something to be universally true that isn't, instead you are talking about a special case of a special case, and one that is not that common.
Why are there so many extinct species if the ancient species had better genetic diversity?
Enjoy

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This message is a reply to:
 Message 1002 by Faith, posted 09-28-2015 6:44 PM Faith has replied

Replies to this message:
 Message 1004 by Faith, posted 09-29-2015 1:07 AM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 1008 of 1034 (770069)
09-29-2015 7:52 AM
Reply to: Message 1004 by Faith
09-29-2015 1:07 AM


Re: Population Genetics - Faith's errors continue unabated
The founding phenotypes soon disappear as the new population reproduces because they were founded on the allele frequencies of the original population. ...
Bizarrely wrong. What is left in the founding population is the allele frequencies carried by the founding individuals, which in the absence of selection pressure against them should continue, and result in new members being similar to the founding population. Unless you introduce new alleles by mutation and unless selection on the population is different than it was on the parent population, you will tend to get similar individuals in the following generations, because they were part of the selected population before.
With new alleles via mutation (without gene flow to the parent population) you will get new variations/traits that cannot appear in the parent population because they don't have access (gene flow) to the mutation.
Different selection pressure will cause different selection of the current alleles in the population and change the frequencies based on which provide better success in survival and breeding.
... Those individuals of course do collectively contain the new gene frequencies, ...
The founding individuals define the gene frequencies of the founding population, the genome and the phenome.
... but the new gene frequencies bring out new phenotypes that eventually eclipse the originals. ...
Magic fantasy is not genetics Faith.
No, they will tend to continue to reproduce the founding phenotypes absent any cause to change (mutations, selection pressure).
If the selection conditions are the same as in the original population then those phenotypes will continue to be selected for, including the tendency for deselection of new mutations that alter the fitness of the individual to the ecology away from the original successful types.
... The originals don't contribute anything to the ultimate phenome (if that is really the word) that will ultimately characterize the new population. ...
More magic fantasy genetics ... lol. More like they contribute everything.
... Their alleles will ...
ie more like everything.
... but in entirely new combinations. ...
A bizarre fantasy of yours.
Only if there is different selection pressure will gradual new combinations become prevalent. The available alleles do not provide enough variation for significant changes on their own, if they did they would have occurred in the original population and if they did occur and were selected against, that selection would continue unless selection changes.
... It's meaningless to talk about the original phenome; what emerges eventually from the new allele frequencies is the entirely new phenome of the new population over generations of reproductive mixing.
Just like it's meaningless to talk about the foundation of the building when you are building a new story ...
The founding phenome sets the allele frequency for that population, the next generation will tend to be similar -- or do you not believe in populations reproducing after their own kind?
New mutations will introduce new variations, different selection will tend to shift allele frequencies, as will additional drift, and all three over time will result in differences from the founding phenome to occur.
The split alone does not cause any allele shift within the founding population.
Enjoy.

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This message is a reply to:
 Message 1004 by Faith, posted 09-29-2015 1:07 AM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 1010 of 1034 (770072)
09-29-2015 8:45 AM
Reply to: Message 1004 by Faith
09-29-2015 1:07 AM


and I am amused
So I step back from the details of the arguments and look at the broad argument ...
The founding phenotypes soon disappear ... the new gene frequencies bring out new phenotypes that eventually eclipse the originals. ... what emerges eventually from the new allele frequencies is the entirely new phenome of the new population over generations of reproductive mixing.
Or in other words transformed into a totally new creature in just a few generation, with no cause other than splitting away from the parent population.
But don't call it a new species or a new genus or a new family, because it is just allele variation that magics the new creatures from the parent population ... with an "entirely new phenom" ... ie entirely different physical traits.
And this process can continue to produce new types as long as the genetics hold out. Perhaps causing phenotype changes like:
quote:
The following discussion is taken from "29 Evidences for Macroevolution; Part 1: The Unique Universal Phylogenetic Tree" Copyright 1999-2002 by Douglas Theobald, Ph.D.
Reptile-mammal transition, with emphasis on the evolution of the interdependent mammalian middle ear ossicles.
Figure 1.4.3. A comparison of the jawbones and ear-bones of several transitional forms in the evolution of mammals. Approximate stratigraphic ranges of the various taxa are indicated at the far left (more recent on top). The left column of jawbones shows the view of the left jawbone from the inside of the mouth. The right column is the view of the right jawbone from the right side (outside of the skull). As in Figure 1.4.1, the quadrate (mammalian anvil or incus) is in turquoise, the articular (mammalian hammer or malleus) is in yellow, and the angular (mammalian tympanic annulus) is in pink. For clarity, the teeth are not shown, and the squamosal upper jawbone is omitted (it replaces the quadrate in the mammalian jaw joint, and forms part of the jaw joint in advanced cynodonts and Morganucodon). Q = quadrate, Ar = articular, An = angular, I = incus (anvil), Ma = malleus (hammer), Ty = tympanic annulus, D = dentary. (Reproduced from Kardong 2002, pp. 274, with permission from the publisher, Copyright 2002 McGraw-Hill)
Since Figure 1.4.3 was made, several important intermediate fossils have been discovered that fit between Morganucodon and the earliest mammals. These new discoveries include a complete skull of Hadrocodium wui (Luo et al. 2001) and cranial and jaw material from Repenomamus and Gobiconodon (Wang et al. 2001). These new fossil finds clarify exactly when and how the malleus, incus, and angular completely detached from the lower jaw and became solely auditory ear ossicles.
Because they're just different phenotypes that appeared from a smaller set of alleles in new arrangements. Right?
Enjoy

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This message is a reply to:
 Message 1004 by Faith, posted 09-29-2015 1:07 AM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 1023 of 1034 (770149)
09-30-2015 8:44 AM
Reply to: Message 1020 by Faith
09-30-2015 3:56 AM


Except that they aren't ...
Faith writes:
I know that and my point was that it makes no difference to the basic pattern. The mechanisms and results are the same no matter what the cause of the reproductive isolation.
This is just self-evidently wrong. You're declaring that the mechanisms of physical population splits, natural selection and genetic drift are the same, despite that they're completely different mechanisms.
Sorry, I've made my case that they are essentially the same in their operations and effects and that's all there is to say in the teeth of your incomprehension.
They are only "essentially the same" if you ignore the differences. (where have I seen this before ... ?)
And you're also declaring the results the same, despite that the results of these mechanisms differ, particularly natural selection which produces adaptation, something the other mechanisms do not.
Yes the results in terms of new gene frequencies bringing out new phenotypes along with reduced genetic diversity occur in all these cases. These are the cases I'm calling "active evolution" where the evolutionary changes are clearly happening, which is not clearly the case in large stable populations or situations where gene flow persists or resumes.
All evolution is "active" whether it is "clearly happening" or not. Evolution to maintain stassis is a very active form of evolution to maintain the level of fitness in a stable environment that has developed over many generations. Gene flow is also evidence of active evolution.
Every time there are offspring there is evolution actively adding mutations to the population genome.
Every time there is mating there is evolution actively selecting the phenotypes that are successful surviving to breed, actively modifying the phenome of the population to fit the ecology.
When you say that the effects of natural selection, population splits and genetic drift are the same you are just plain wrong.
Natural selection actively sorts the population for phenotypes that survive to breed successfully in every generation.
Population splits may divide the population evenly or not evenly, it may result in some differences in allele frequencies and it may not. The split may occur because some phenotypes have evolved a trait beneficial in a different ecology that they can now use, but the parent population is not well suited for (black pocket mice), but that is a form of natural selection taking advantage of opportunities.
Genetic drift occurs to breeding populations, and it happens when traits are eliminated from the population with no selection of the individuals for fitness to the ecology. It can even eliminate beneficial traits.
Also, population splits do lead to adaptations, as I've often argued here. ...
Except when it doesn't, as you have often been told. The new adaptations that do occur would be due to mutation and selection in a different ecology with different selection pressure.
... I don't accept Darwin's understanding of the adaptations of the different finch beaks for instance, I believe the beak came first, through new gene frequencies brought about by a population split, probably a migration of a subpopulation to a new territory, and the beak found a food suited to it and that's how the adaptation occurred. ...
Except the evidence shows that you are wrong. A change in beak size was (gosh) actually observed by Peter and Rosemary Grant in response to climate change on one island -- it got dryer, seeds got harder, beaks became bigger, it got wetter, seeds got softer, beaks became smaller.
So I suppose you will argue that the beak size change came first and that this caused the climate changes to accommodate the new beaks?
In some cases pre-adaptation can occur, such as the black pocket mice, when individuals benefit from a new trait that allows them to survive and breed in a new ecology, but is by no means the normal path of evolution.
It is pointless discussing your fantasy further because it is based on false perceptions like these. Fix the errors first then we can look at the rest.
You can't pretend that the situations of a founding event apply to all breeding population with nothing but your biased\underinformed imagination. It isn't a new paradigm fighting for acceptance because you don't have evidence for it and ignore evidence contrary to it.
Enjoy.
Edited by RAZD, : clrty
Edited by RAZD, : mo

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This message is a reply to:
 Message 1020 by Faith, posted 09-30-2015 3:56 AM Faith has replied

Replies to this message:
 Message 1025 by Faith, posted 09-30-2015 12:52 PM RAZD has replied
 Message 1032 by NoNukes, posted 10-21-2015 10:38 PM RAZD has seen this message but not replied
 Message 1033 by NoNukes, posted 10-21-2015 11:44 PM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 1027 of 1034 (770173)
09-30-2015 9:42 PM
Reply to: Message 1025 by Faith
09-30-2015 12:52 PM


Re: Except that they aren't ...
The effects, as I clearly described them, are the same in all three cases.
Let me fix that for you:
The effects, as science clearly describes them, are different in all three cases.
As has been clearly documented ...
bye
Take your time off to review the evidence and the facts around it.
Enjoy

we are limited in our ability to understand
by our ability to understand
RebelAmerican☆Zen☯Deist
... to learn ... to think ... to live ... to laugh ...
to share.


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This message is a reply to:
 Message 1025 by Faith, posted 09-30-2015 12:52 PM Faith has not replied

Replies to this message:
 Message 1028 by Coyote, posted 09-30-2015 10:11 PM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 1029 of 1034 (770175)
09-30-2015 11:08 PM
Reply to: Message 1028 by Coyote
09-30-2015 10:11 PM


Re: Except that they aren't ...
These are the kind of arguments you might expect when belief dominates evidence.
Indeed. But a simple test of the claim is that if the three systems are "essentially the same" then why are there three systems defined and described instead of one.
Enjoy

we are limited in our ability to understand
by our ability to understand
RebelAmerican☆Zen☯Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 1028 by Coyote, posted 09-30-2015 10:11 PM Coyote has replied

Replies to this message:
 Message 1030 by Coyote, posted 10-01-2015 12:36 AM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 1031 of 1034 (770210)
10-01-2015 10:03 AM
Reply to: Message 1030 by Coyote
10-01-2015 12:36 AM


Re: Except that they aren't ...
There you go, using evidence again.
Yep thet evi-dunce is the work of the devil
You know that's not going to work. ...
Ya can't fool a TVUE believer
... Surely you've learned that by now!
Don't call me Shirley

we are limited in our ability to understand
by our ability to understand
RebelAmerican☆Zen☯Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 1030 by Coyote, posted 10-01-2015 12:36 AM Coyote has seen this message but not replied

  
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