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Author Topic:   A test for claimed knowledge of how macroevolution occurs
RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 540 of 785 (856170)
06-28-2019 8:05 AM
Reply to: Message 532 by Faith
06-28-2019 12:48 AM


Genetic loss is NOT a necessity, Genetic Change is
RAZD diagrams such a situation, and in fact a whole series of populations, without recognizing that each must entail genetic loss. ...
Because it doesn't. What it does entail is change.
Evolution is a two-step feedback response system that is repeated in each and every generation:
Mutations add variation, selection tends to remove the least useful (for survival) and desirable (for reproduction). Thus when a mutation provides a trait that is more useful or desirable for the population than an existing trait it tends to replace it. They could overlap for a while, with increased genetic variation.
Each generation entails mutation (gain) and selection (loss), and the net result can be more or less than the previous generation -- there is no set restriction on the amount of variation for any breeding population.
If only you would open your eyes you would see this fact.
Enjoy
Edited by RAZD, : .

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This message is a reply to:
 Message 532 by Faith, posted 06-28-2019 12:48 AM Faith has not replied

  
RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 541 of 785 (856171)
06-28-2019 8:24 AM
Reply to: Message 528 by Faith
06-27-2019 5:44 PM


change over time, each generation changes
As usual you keep ignoring all the arguments and examples I've given that prove it is necessary to lose genetic diversity to get new phenotypes. All you are doing is trying to sound authoritative without actually saying anything.
No, I dont ignore your falsified argument, I just point out that it is falsified and thus irrelevant to reality.
What you need to get new phenotypes is new traits. You don't get this by remixing old traits, you get them from changes -- mutations. Each and every generation's gene pool changes, generation after generation, and this provides changes to phenotypes over time.
For example the Pelycodus increase in body size generation after generation until the point is reached that the smallest individual is larger than the largest individual of the original population. We also see that the spread of size from smallest to largest changes with each generation, sometimes increasing in spread, sometimes decreasing.
It should be obvious to anyone with open eyes that the increase in body size until the whole population is larger than the original population is not just due to a loss of genetic material for body size, but that the genes for body size are modified for increased size: changes in the overall size that prove beneficial for survival or reproduction. The ToE explains this, your model only explains the loss of smaller sizes, ie only half of what happened.
No, I've made the case, and made it many many times over many threads and even in this thread, and I have indeed presented the evidence of domestic breeding which is about as clear a description as you can get of what happens to develop new phenotypes, and I've given plenty of illustrations of that same thing happening in the wild. Interesting that you never discuss any of this.
And every time you have been told and demonstrated why domestic breeding does not model natural evolution. You have been shown over and over how mutations add to diversity, and increased opportunity for species, like the pocket mice. These examples invalidate your argument, and when added to your cherry picked examples they serve to show your explanation is incomplete and less accurate than the explanation provided by the ToE which explains all the evidence.
If only you would open your eyes and look at all the evidence.
Enjoy
Edited by RAZD, : .

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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 543 of 785 (856176)
06-28-2019 9:33 AM
Reply to: Message 529 by Faith
06-27-2019 6:18 PM


Re: The genetic loss idée fixe vs reality
Breeders cull traits to preserve their breeds, for sure, but traits are not necessarily mutations, in fact most of the time all they are doing is choosing to mate individuals that have the positive traits they desire and don't have to focus on the unwanted traits. You haven't shown, and cannot show, that mutations are ever a problem in breeding, at any stage of the process. ...
Exactly, they cull out the new mutations to preserve the breed. Natural selection operates on a different paradigm -- traits that are useful for survival or desirable for reproduction, it not could care less about preserving a phenotype, just what ever works. It doesn't matter if it is new or old.
This again is why breeding is not a model for evolution.
... You assume that all traits are the result of mutations, and that always has been an assumption and remains an assumption but you take it so for granted it is just about impossible to get you to consider any other way of looking at it. ...
We know mutations modify traits and cause new phenotypes, and have known this for decades.
... Well, that is of course the standard problem in paradigm conflicts. And getting the Old Guard to rethink their stuff is asking WAY too much, isn't it?
When you have evidence against you and no supporting evidence, yes.
And here we have the very center of the paradigm clash. You seem to be unable to think at all about any of this without assuming evolution and assuming mutation as the fuel of that evolution. You think the traits of the chosen breed MUST have evolved by mutation from the parent stock. You can't prove this, you assume it, it's simply an article of the ToE faith that isn't questioned.
Because it is based on evidence. We don't see traits for floppy ears, spotted color fur and waggy tails in wolves. We don't see them in wild foxes either, but a Russian breeding program to make tamer and thus easier to raise for the fur trade ended up with those traits -- due to mutations that decreased the adrenaline and increased serotonin in the foxes.
We know there are genetic differences between wolves to dogs and differences between breeds. You don't get Great Danes from wolves by throwing out dachshund dog traits and vice-versa because those traits don't exist in wolf genomes. You get them from mutations.
My contrasting model/theory is that there is no difference whatever in the genetic material between generations, ...
And in this you are wrong.
No mutations needed, dear Razz. ...
But you cannot ignore that they are there if you want to model reality. It's not that they are needed (which is wrong paradigm thinking) but that they are there, and thus they need to be included in a complete explanation.
We know that they are there in every generation, we know that this changes the gene pool for every generation, and we know that they need to be considered in any explanation of observed changes in a species, because anything less would be a half vast explanation.
It's a different paradigm from your evolutionary pattern, ...
That doesn't cover all the evidence, nor explain all that is observed, and therefore not useful.
I just wish you would open your eyes.
Enjoy

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This message is a reply to:
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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 550 of 785 (856203)
06-28-2019 12:18 PM
Reply to: Message 539 by Faith
06-28-2019 2:42 AM


Re: The genetic loss idée fixe vs reality
Mutation, migration (gene flow), genetic drift, and natural selection as mechanisms of change;
and
The importance of genetic variation; The random nature of genetic drift and the effects of a reduction in genetic variation; How variation, differential reproduction, and heredity result in evolution by natural selection; and
Are not part of my posts in this thread. Please designate source. Not that they are wrong, just want to be clear on what comes from where.
As I was thinking through this list it hit me that Mutation and gene flow ADD to the genetic variability, and must create a scattered effect of phenotypes, and must create a scattered effect of phenotypes. ...
Mutations add to the gene pool, gene flow distributes the gene pool in the breeding population.
... What makes for a homogeneous species, on the other hand, is the subtractive processes of selection. ...
or the spread of new mutations/genes throughout the breeding population, which can occur with a dominant gene, or because selection pressure is low.
... It took me a while to figure out "genetic drift" and now I see it as just one form of species creation by isolating a portion of the population. ...
Not necessarily. It's an arbitrary (stochastic) loss of genetic (gene pool) material because it doesn't make it through breeding, but it doesn't make the species different from before, just reduced in gene pool material. Stochastic processes involve arbitrary deaths that are not related to survival or reproduction (volcanic eruptions, earthquakes, forest fires, floods, etc).
... It isn't a process or a mechanism at all and it's hard to figure out why it's even on the list.
It is a process that affects the gene pool.
I note that the definition now includes "the effects of a reduction in genetic variation" which seems **** it could be an attempt to take into account what I keep arguing. This is new to the definition; it wasn't there when I was coming to my view of reduced genetic variability. AND it's not my view anyway: Calling it "genetic variation"is the clue that it's not the same thing as "genetic variability." "variation is a result; variability is a potential. But this is probably not the place to try to get into this discussion.
Genetic drift may be one of the prime drivers for new species, as lost genetic material is replaced by new material (mutations) that have less competition in being selected, changing the gene pool.
This strikes me as gobbledygook beyond my ability to sort out on short notice, but maybe I can come back to it. "...RESULT in evolution by natural selection" makes no sense whatever. At least it explains that it is the randomness of genetic drift that gets it on the list. The problem with that is, as I was thinking through how species develop from population splits, ALL such ways species get created are random in the wild. It's only in domestic breeding that they aren't random.
Now I'm regretting getting off into all this but I'm going to leave it as a record of how confused the definitions can get, and get back to your post if I can.
Again, that was not my post and it seems you've left out some things. Providing a source to see context would help. For now it just shows how confused you are.
I certainly agree that "evolution in the wild doesn't have to eliminate everything that doesn't fit [some] chosen set of traits" but I never ever suggested that kind of similarity with breeding anyway. I've always said it's a random process. What happens is that a set of traits is randomly selected by the separation of a portion of the parent population to become a daughter population. That random separation of a certain group of individuals forms a new gene pool with new gene frequencies ...
Natural selection is not random, it selects among available traits by what is useful for survival and reproduction.
The separation of the population may be due to stochastic events and it may result in a smaller gene pool, but that isn't necessarily the case.
You can also have a new mutation/trait that allows the species to expand into a new area. Black fur pocket mice for instance, able to inhabit lava fields that are dangerous for tan furred mice.
The larger and more homogeneous the population the more likely the gene pool will be similar.
... That random separation of a certain group of individuals forms a new gene pool with new gene frequencies that when blended together over some number of generations of breeding brings out a distinctively new species from a new group of phenotypes created by the new gene frequencies in sexual recombination for those generations. It's the same process as what happens in domestic breeding except that a set of traits is randomly selected out of the population to form the new species.
You don't get new phenotypes with the same old gene pool or a subset of it.
Here we have another example of how different my model is from yours. The ToE says that evolution is powered by benefit to survival and reproduction, but in my model no such selective pressures need apply and usually don't. ALL IT TAKES TO GET A NEW SPECIES IS THE NEW GENE FREQUENCIES BROUGHT ABOUT BY THE SEPARATION AND ISOLATION OF A PORTION OF THE ORIGINAL POPULATION. That's ALL it takes. No selective pressure at all, no ecological pressure, nothing environmental at all. The genetic rearrangements are the whole thing. There COULD be some input from natural selection but there's no need for it and I don't think it happens much.
Here we have another example of how different my model is from yours. Mine works, yours doesn't. Mine explains all the evidence, yours only explains part of it ... at best, and it ignores the fact that every generation has new mutations that change the gene pool. This means that over time (generations) the gene pool changes and new phenotypes from original genes is no longer possible -- the genes have been replaced or modified. You get new phenotypes with new genes.
Although the ToE was invoked to explain the evolution of the larger head and jaw of the Pod Mrcaru lizards after thirty years in isolation, meaning they were actively adapting to the tougher kind of plant they came to prefer, but there is no hint that there was any absnese of the kind of food they had when they were still part of the parent population, they just came to prefer the tougher food. MY EXPLANTION OF THIS IS THAT their new gene frequencies contained the emphasis on larger head and jaw and that alone brought out that characteristic. Then BECAUSE THEY HAD THAT CHARACTERISTIC, THEN they wree drawn to the tougher kind of food that they could now eat. ...
Yep. Once they had the mutation for larger jaw they were able to take advantage of the opportunity of the tougher plant food. Evolution in response to challenges and opportunities.
At that point you don't WANT change, you WANT preservation. All the changes occurred on the way to establishing the breed.
As I said, mutations allowed the new breed type to exist and then all further mutations were culled. This is why breeding is not a model for evolution: it is a specific type of selection -- it doesn't model natural selection and it doesn't include mutations.
It's true that I don't try enough to answer these basic tenets of evolution which is probably the cause of a lot of miscommunication. I content myself with trying to describe my different model but I see that it has to try to answer all these other objections more than I take into account.
True.
I think what I need to do is try to put together a lengthy article trying to cover the whole shebang since I now think I'm leaving too much out of these discussions. Not something to do at EvC of course.
Be prepared for sharp criticism.
Enjoy

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This message is a reply to:
 Message 539 by Faith, posted 06-28-2019 2:42 AM Faith has replied

Replies to this message:
 Message 552 by Faith, posted 06-28-2019 7:13 PM RAZD has replied

  
RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 557 of 785 (856274)
06-29-2019 9:02 AM
Reply to: Message 552 by Faith
06-28-2019 7:13 PM


Re: The genetic loss idée fixe vs reality
Lengthy cut and paste warning. You can also read online and see the pictures that go with the text.
I copied them off the Google page on "processes of evolution." They are from the Cal Berkeley website on evolution.
Thanks. One of my favorite sites for teaching about evolution. The full listing is:
quote:
Mechanisms: the processes of evolution
Evolution is the process by which modern organisms have descended from ancient ancestors. Evolution is responsible for both the remarkable similarities we see across all life and the amazing diversity of that life ” but exactly how does it work?
Fundamental to the process is genetic variation upon which selective forces can act in order for evolution to occur. This section examines the mechanisms of evolution focusing on:
  • Descent and the genetic differences that are heritable and passed on to the next generation;
  • Mutation, migration (gene flow), genetic drift, and natural selection as mechanisms of change;
  • The importance of genetic variation;
  • The random nature of genetic drift and the effects of a reduction in genetic variation;
  • How variation, differential reproduction, and heredity result in evolution by natural selection; and
  • How different species can affect each other's evolution through coevolution.

So you left off the part about genetic variation (Mendelian genetics plus mutations) being fundamental to evolution and how the ecology (different species affect each other's evolution) affects selection.
May I suggest that you continue on at least to the next two pages?
quote:
Descent with modification
We've defined evolution as descent with modification from a common ancestor, but exactly what has been modified? Evolution only occurs when there is a change in gene frequency within a population over time. These genetic differences are heritable and can be passed on to the next generation ” which is what really matters in evolution: long term change.
Compare these two examples of change in beetle populations. Which one is an example of evolution?
  1. Beetles on a diet
    Imagine a year or two of drought in which there are few plants that these beetles can eat.
    All the beetles have the same chances of survival and reproduction, but because of food restrictions, the beetles in the population are a little smaller than the preceding generation of beetles.
  2. Beetles of a different color
    Most of the beetles in the population (say 90%) have the genes for bright green coloration and a few of them (10%) have a gene that makes them more brown.
    Some number of generations later, things have changed: brown beetles are more common than they used to be and make up 70% of the population.
Which example illustrates descent with modification ” a change in gene frequency over time?
The difference in weight in example 1 came about because of environmental influences ” the low food supply ” not because of a change in the frequency of genes. Therefore, example 1 is not evolution. Because the small body size in this population was not genetically determined, this generation of small-bodied beetles will produce beetles that will grow to normal size if they have a normal food supply.
The changing color in example 2 is definitely evolution: these two generations of the same population are genetically different. But how did it happen?
quote:
Mechanisms of change
Each of these four processes is a basic mechanism of evolutionary change.
Mutation
A mutation could cause parents with genes for bright green coloration to have offspring with a gene for brown coloration. That would make genes for brown coloration more frequent in the population than they were before the mutation.
Migration
Some individuals from a population of brown beetles might have joined a population of green beetles. That would make genes for brown coloration more frequent in the green beetle population than they were before the brown beetles migrated into it.
Genetic drift
Imagine that in one generation, two brown beetles happened to have four offspring survive to reproduce. Several green beetles were killed when someone stepped on them and had no offspring. The next generation would have a few more brown beetles than the previous generation ” but just by chance. These chance changes from generation to generation are known as genetic drift.
Natural selection
Imagine that green beetles are easier for birds to spot (and hence, eat). Brown beetles are a little more likely to survive to produce offspring. They pass their genes for brown coloration on to their offspring. So in the next generation, brown beetles are more common than in the previous generation.
All of these mechanisms can cause changes in the frequencies of genes in populations, and so all of them are mechanisms of evolutionary change. However, natural selection and genetic drift cannot operate unless there is genetic variation ” that is, unless some individuals are genetically different from others. If the population of beetles were 100% green, selection and drift would not have any effect because their genetic make-up could not change.
Note each cause of changes to the gene pool are discussed in greater detail in following pages. I strongly recommend you take the time read them all. If you have any questions feel free to ask.
The better you understand the scientific model the better able you should be to discuss it versus your model.
Enjoy

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This message is a reply to:
 Message 552 by Faith, posted 06-28-2019 7:13 PM Faith has replied

Replies to this message:
 Message 569 by Faith, posted 06-29-2019 9:10 PM RAZD has seen this message but not replied
 Message 573 by Faith, posted 06-30-2019 7:01 AM RAZD has replied

  
RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 580 of 785 (856377)
06-30-2019 10:09 AM
Reply to: Message 573 by Faith
06-30-2019 7:01 AM


Re: The genetic loss idea IS reality
Maybe if I write an article I'll discuss all of this, but it's nothing much: only mutations which you believe make new alleles and I don't; plus gene flow, which adds nothing, just reshuffles what's already in the gene pool, and gene flow just interrupts and muddies up the formation of a new species; plus sexual recombination which also shuffles what's already there, and I consider this to be a main "mechanism" for bringing out new phenotypes in establishing a new population/species in reproductive isolation.
Let's break this down with a simple example: two genes each with two alleles
A a
B AB aB
b Ab ab
This is all you get with Mendelian mixing of genes. The gene pool frequency includes A, a, B, and b. Cut the population down and still have all these phenotypes OR you have a subset of them. Let's say AB is not included in the population split, so you have
A a
B aB
b Ab ab
Nothing new there. A change in gene frequency, yes, but all these phenotypes were in the original population and there is no new combination. The gene pool frequency still includes A, (2)a, B, and (2)b. When they mate you have
A (2)a
B AB (2)aB
(2)b (2)Ab (4)ab
So you see the shift in gene frequency but no new phenotypes. You still have AB, but Ab and aB are twice as frequent and ab is 4 times as frequent phenotypes.
This is what genetic drift does. Selection is not included, mutations are not included. The gene pool frequency still includes (3)A, (4)a, (3)B, and (4)b. Now we go another generation:
(3)A (4)a
(3)B (9)AB (12)aB
(4)b (12)Ab (16)ab
This is what happens in the generation after genetic drift. Selection is not included, mutations are not included. The gene pool frequency still includes (21)A, (28)a, (21)B, and (28)b. You still have AB, but Ab and aB are 1.333 times as frequent and ab is 1.778 times as frequent phenotypes.
The population is trending back to the original frequencies, a process that will continue as more generations are considered.
... and I consider this to be a main "mechanism" for bringing out new phenotypes in establishing a new population/species in reproductive isolation.
There are no new phenotypes, there are no phenotypes that cannot breed with the other phenotypes in the breeding population. They all existed before, they all interbred before.
FAIL.
I know it's hard to believe but I actually think the ToE is simply WRONG, wrong about most of what it has to say, although it has provided some concepts I make use of, such as the importance of new gene frequencies. New gene frequencies sexually recombined over enough generations to create a new homogeneous population distinct from the parent population and other daughter populations. ...
As we can see from the above example, this just does not happen. A "new homogeneous population" forms but it tends to be more and more like the parent population as generations pass.
... That's basically my view of what happens in "evolution." You don't need natural selection, you don't need mutations, you don't need ecological or any other kind of environmental pressure. New combinations of existing genes in an isolated population is all you need, and this over time will entail loss of genetic diversity. NECESSARY loss, needed to develop new phenotypes.
And when we look at the above example -- with no selection, no mutations, and no ecological change -- you just do not get a loss of any genes or any new phenotype.
FAIL
Enjoy

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This message is a reply to:
 Message 573 by Faith, posted 06-30-2019 7:01 AM Faith has replied

Replies to this message:
 Message 581 by Faith, posted 06-30-2019 11:22 AM RAZD has replied

  
RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 587 of 785 (856386)
06-30-2019 1:26 PM
Reply to: Message 581 by Faith
06-30-2019 11:22 AM


Testing Faith's genetic loss idea against reality
You aren't going to see much of anything with one gene, ...
The example has two genes, each with two alleles.
... it's the mixture of new frequencies of hundreds, thousands of genes, that brings out the new phenotypic picture. ...
Why would this be any different? You still are using genes that exist in the parent gene pool, phenotypes that exist in the breeding population, and as the example in Message 580 shows you don't get a new phenotype that is not already in the breeding population -- when you ignore selection, mutation and ecological forces, and you are positing a "homogeneous" parent population (and I think you are misusing that word ... what you mean, I believe, is well mixed, all genes/alleles with virtually the same frequencies).
Consider adding a third gene with two alleles to the above example, you would end up with three tables of possible combinations:
A a
B AB aB
b Ab ab
A a
C AC aC
c Ac ac
B b
C BC bC
c Bc bc
Now rather obviously each of these tables would go through the same process generation after generation as in the original example. You don't get a phenotype that is not in the parent population. You don't get a phenotype that cannot breed with the parent population or a similar sub-population.
OR we can add a third allele to one of the genes:
A a a'
B AB aB a'B
b Ab ab a'b
Now, if we consider that an event removes all individuals with the same allele -- say the a' allele -- then you end up with the original example, a breeding population with all phenotypes that exist in the parent population. Yes you have some genetic loss, but you don't have a new phenotype and you don't have a phenotype that cannot breed with the parent population or a similar sub-population -- you just can't get a phenotype that can't breed with the other phenotypes, because you have not created any barrier to breeding within the species/breeding population.
It should also be readily apparent that adding a third gene with two or three alleles will not create anything new, just the mild gene frequency shift seen in the original example or variations on it. We can keep expanding the table, but the results will be similar: no new phenotype that never existed before, no new phenotype that is not capable of breeding with the parent population.
... Although you could get a new population with nothing but, say, changed striping, say in a raccoon population that split off from another population, ...
The genes for variations in striping would exist in the parent population, and you have not shown that it would create a barrier to breeding.
... in large populations with lots of genetic diversity, like the wildebeests, more than one characteristic is going to change: blue hide, smaller stature, different antlers. The alleles for all those charcteristics are in the larger population but they don't get expressed until a new set of gene frequencies allows them to be expressed in the new population.
But you have not shown that they don't or can't get expressed in the original population, (which you posit is "homogeneous"), so there is no reason for them not being expressed -- when you ignore selection, mutation and ecological forces, and you are positing a "homogeneous" parent population (and I still think you mean is well mixed).
Throw in selection and ecological forces and you will see more shift the phenotypes, but you still will not get anything that could not exist in the parent population and breed with the parent population. You can achieve a different variety (different populations with different coloration, say) at best, but not a new species.
We do see this happening, but not with a result of a new species without a barrier to reproduction.
Perhaps the best example for you is the Greenish Warbler, where the original population splits and splits and splits again, with each breeding population being characterized by slightly different coloration and slightly different mating songs -- different varieties. They each have hybrid zones between one population and the next except at the close of the ring, where you have two varieties that do not readily mate (although there are occasional hybrids).
quote:
Genetic data show a pattern very similar to the pattern of variation in plumage and songs. The two northern forms viridanus and plumbeitarsus are highly distinct genetically, but there is a gradient in genetic characteristics through the southern ring of populations. All of these patterns are consistent with the hypothesis, first proposed by Ticehurst (1938), that greenish warblers were once confined to the southern portion of their range and then expanded northward along two pathways, evolving differences as they moved north. When the two expanding fronts met in central Siberia, they were different enough that they do not interbreed.
The different genomes show mutations that added or modified alleles not in the original (or previous) breeding populations.
That is where new phenotypes arise, and that is where breeding isolation develops.
You really should think about this.
Enjoy
Edited by RAZD, : .
Edited by RAZD, : ..
Edited by RAZD, : clrty

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This message is a reply to:
 Message 581 by Faith, posted 06-30-2019 11:22 AM Faith has replied

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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 607 of 785 (856546)
07-01-2019 3:32 PM
Reply to: Message 601 by Faith
07-01-2019 1:31 PM


Re: The genetic loss idée fixe vs reality
... In the main population of wildebeests they are all generally brown in appearance, despite their genetic diversity. I've often wondered what it is genetically that creates that situation. I think now it's that all the separate traits are at a nondramatic level, ...
(fixed)
What is most likely is that it is sexual selection for the more average phenotype traits -- leading to apparent stasis in such populations. In this way large stable populations in static ecological environments would select for stasis.
In humans, tests have shown that perceptions of beauty/handsomeness are actually for average phenotypes.
This is logical because the more average the trait the more likely they are good for fitness (for survival and reproduction) in a static (or near static) ecological environment.
See Sexual Selection, Stasis, Runaway Selection, Dimorphism, & Human Evolution for more.
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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 628 of 785 (856569)
07-01-2019 4:49 PM
Reply to: Message 610 by Faith
07-01-2019 3:40 PM


Re: The genetic loss idée fixe vs reality
Stage three new characteristics should start to emerge from the new combinations of alleles, including a new pattern of markings on an animal like a raccoon.
There are no new combinations of alleles that were not possible in the parent population, and if you ignore selection, mutation and ecological forces (as you have claimed), in what you call a "homogeneous" population, then those combinations should exist in the parent population.
Variations in markings would be due to modified development (see silver foxes) from changes in hormone levels or modified genes for markings. Otherwise they should be in the parent population as well.
And reproductive stages beyond that should bring out even more new characteristics, again all from recombination of the new gene frequencies.
Again, there is no new characteristics when all you rely on is pure Mendelian reproduction, if you ignore selection, mutation and ecological forces (as you have claimed), in what you call a "homogeneous" population, then those combinations should exist in the parent population.
The end result should be that the whole population will have blended together to form a new appeaerance of homogeneity that is distinct from the original population and from all other populations of the same species. A completely new pattern of markings would probably identify the new raccoon population.
At best you get a variety of racoon, not a new species that cannot reproduce with the parent or other similar sub-populations.
I expect my opponents to describe their own completely different scenario with the mutations and the ecological selection pressure and so on, and even be adamant that it's the correct scenario based on the ToE, but I strongly object to telling me I'm wrong because I don't share that scenario. No, if that's going to be the attitude, sorry, YOU are wrong.
Typical. Open your eyes, Faith.
You are limited in your ability to understand by your ability to understand ...
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This message is a reply to:
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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 633 of 785 (856623)
07-01-2019 10:05 PM
Reply to: Message 630 by Faith
07-01-2019 5:07 PM


Re: The genetic loss idée fixe vs reality
Yes, but this becomes a semantic problem because one often runs across such phrases as "species of raccoon" and "species of wildebeest" although there is no reason to think they can't interbreed. I can go back to "variety" if necessary" but I keep finding that no particular terminology is sufficient.
That's more your problem than one of description by biologists. You are blinded/hampered by your insistence, idée fixe, regarding speciation by biological science definitions.
quote:
Raccoon
As of 2005, Mammal Species of the World recognizes 22 subspecies of raccoons.[31] Four of these subspecies living only on small Central American and Caribbean islands were often regarded as distinct species after their discovery. These are the Bahamian raccoon and Guadeloupe raccoon, which are very similar to each other; the Tres Marias raccoon, which is larger than average and has an angular skull; and the extinct Barbados raccoon. Studies of their morphological and genetic traits in 1999, 2003 and 2005 led all these island raccoons to be listed as subspecies of the common raccoon in Mammal Species of the World's third edition. A fifth island raccoon population, the Cozumel raccoon, which weighs only 3 to 4 kg (6.6 to 8.8 lb) and has notably small teeth, is still regarded as a separate species.[32][33][34][35]
Subspecies can interbreed, but seem to be isolated for now.
Note that four subspecies were regarded as different species until genetic data showed otherwise.
Note further that your claim of isolation and gene loss leads to new species is not born out. At best you get varieties or subspecies. The morphological (phenotype) variations are not sufficient to prevent breeding.
Let's talk skunks -- here are six species of skunks in America:
So cute.
The upper left and middle pictures show striped skunks. The upper right is a (probably) western spotted skunk, and the bottom picture shows a hooded skunk.
There is one species of striped skunk, Mephitis mephitis. Note the large variation in stripe width in the two pictures.
There are four species of spotted skunk:
There is one species of Hooded skunk, Mephitis macroura, and yes it is in the same genus as the striped skunk, they even look similar. All the skunks are grouped in the taxon family Mephitidae. There is an area of overlap in habitat between the striped and hooded skunks along the border between the US and Mexico.
Note that there is significant variation in the width of the side stripe in the two striped skunk pictures, but they are still of the same species. They interbreed. The one with wide side stripes looks more like the hooded skunk.
There are 13 Subspecies of striped skunks, with varying widths of the side stripes, some very wide and closer to the hooded skunk in appearance, and some with almost non-existing side stripes.
So what's your take on these skunks? Do the changes in widths of the stripes lead to speciation?
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This message is a reply to:
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Replies to this message:
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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 642 of 785 (856721)
07-02-2019 1:05 PM
Reply to: Message 632 by Faith
07-01-2019 6:01 PM


Re: The genetic loss idée fixe vs reality
Because mutations can only do what the gene does, ...
When the gene is for fur color, and the mutation changes the fur color to black from tan in pocket mice, the gene still does what the gene does -- fur color. This is how new alleles arise, and they have an effect on the phenotype and thus on selection.
... they can't go outside the genome ...
Of course they can't -- the mutation changes the genome to include it.
quote:
In the fields of molecular biology and genetics, a genome is the genetic material of an organism. It consists of DNA (or RNA in RNA viruses). The genome includes both the genes (the coding regions) and the noncoding DNA,[1] as well as mitochondrial DNA[2] and chloroplast DNA. The study of the genome is called genomics.
So when the DNA changes by mutation, the genome changes.
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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 693 of 785 (856982)
07-04-2019 1:36 PM
Reply to: Message 630 by Faith
07-01-2019 5:07 PM


Faith's "homogenous" population
and if you ignore selection, mutation and ecological forces (as you have claimed), in what you call a "homogeneous" population, then those combinations should exist in the parent population.
As I say above, they could, but it's not necessary for them to have been expressed there beyond the occasional occurrence which is hardly noticeable in a large population of motley traits with a general homogeneous appearance. It's all a matter of gene frequencies.
Is this what you mean by a "homogeneous" population, that they have a "general homogeneous appearance" ... (with some variation presumably in size)?
Would "motley traits" mean the various traits (color, legs, horns, etc) that go to make up each individual?
Curious.
... It's all a matter of gene frequencies.
I assume they were all in the parent population but for some reason more potential than expressed. ...
So there is also the case of a very large herd population with high genetic diversity that can be the source of strongly different traits in daughter populations. ...
A large herd with "high genetic diversity" would have many variations in phenotypes with "strongly different traits" ... as shown by the analysis with Mendalian inheritance in Message 587.
... So I now have the idea that traits don't necessarily manifest in some obvious way at first, just enough to be selected in breeding, or even in nature, but not enough to show up in a herd unless you go through it individual by individual. It takes the new gene frequencies to begin to emphasize such traits and bring them to observable expression in the new population. You all rely on mutations to explain all this although I don't think that's even possible, but in any case my model has new characteristics emerging even in dramatic ways in daughter populations that didn't get expressed in the parent population, or not to any noticeable degree.
But you ignore selection, mutation and ecological forces, in the formation/development of all phenotypes, and you are positing a "homogeneous" parent population, so you have no mechanism to make traits that don't "necessarily manifest in some obvious way at first, just enough to be selected in breeding, or even in nature, but not enough to show up in a herd unless you go through it individual by individual." Rather they should all be seen in the parent population.
And how do you know that the changes in the sub-populations are not due to mutations?
Curious again.
Enjoy
Edited by RAZD, : .

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This message is a reply to:
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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 705 of 785 (857055)
07-05-2019 8:28 AM
Reply to: Message 637 by Faith
07-02-2019 4:43 AM


Species and Speciation Events
I'm OK with varieties or subspecies but as I said one often hears such populations referred to as species.
The biological test for species is whether or not they interbreed with other populations. That's because of the definition of species used in biology.
quote:
Defining speciation
Speciation is a lineage-splitting event that produces two or more separate species. Imagine that you are looking at a tip of the tree of life that constitutes a species of fruit fly. Move down the phylogeny to where your fruit fly twig is connected to the rest of the tree. That branching point, and every other branching point on the tree, is a speciation event. At that point genetic changes resulted in two separate fruit fly lineages, where previously there had just been one lineage. But why and how did it happen?
The branching points on this partial Drosophila phylogeny represent long past speciation events.
Look familiar?
There are some difficulties, however:
quote:
Defining a species
A species is often defined as a group of individuals that actually or potentially interbreed in nature. In this sense, a species is the biggest gene pool possible under natural conditions.
For example, these happy face spiders look different, but since they can interbreed, they are considered the same species: Theridion grallator.
That definition of a species might seem cut and dried, but it is not ” in nature, there are lots of places where it is difficult to apply this definition. For example, many bacteria reproduce mainly asexually. The bacterium shown at right is reproducing asexually, by binary fission. The definition of a species as a group of interbreeding individuals cannot be easily applied to organisms that reproduce only or mainly asexually.
Also, many plants, and some animals, form hybrids in nature. Hooded crows and carrion crows look different, and largely mate within their own groups ” but in some areas, they hybridize. Should they be considered the same species or separate species?
If two lineages of oak look quite different, but occasionally form hybrids with each other, should we count them as different species? There are lots of other places where the boundary of a species is blurred. It's not so surprising that these blurry places exist ” after all, the idea of a species is something that we humans invented for our own convenience!
Classification is for our use in discussions, and they are subject to change when information provides new insights.
quote:
Carrion Crow: Distribution and genetic relationship to hooded crows
The carrion crow (Corvus corone) and hooded crow (Corvus cornix, including its slightly larger allied form or race C. c. orientalis) are two very closely related species[7] whose geographic distributions across Europe are illustrated in the accompanying diagram. It is believed that this distribution might have resulted from the glaciation cycles during the Pleistocene, which caused the parent population to split into isolates which subsequently re-expanded their ranges when the climate warmed causing secondary contact.[8][9]
A map of Europe indicating the distribution of the carrion and hooded
crows on either side of a contact zone (white line) separating the two species
Poelstra and coworkers sequenced almost the entire genomes of both species in populations at varying distances from the contact zone to find that the two species were genetically identical, both in their DNA and in its expression (in the form of mRNA), except for the lack of expression of a small portion (<0.28%) of the genome (situated on avian chromosome 18) in the hooded crow, which imparts the lighter plumage colouration on its torso.[8] Thus the two species can viably hybridize, and occasionally do so at the contact zone, but the all-black carrion crows on the one side of the contact zone mate almost exclusively with other all-black carrion crows, while the same occurs among the hooded crows on the other side of the contact zone.
It is therefore clear that it is only the outward appearance of the two species that inhibits hybridization.[8][9] The authors attribute this to assortative mating (rather than to ecological selection), the advantage of which is not clear, and it would lead to the rapid appearance of streams of new lineages, and possibly even species, through mutual attraction between mutants. Unnikrishnan and Akhila propose, instead, that koinophilia is a more parsimonious explanation for the resistance to hybridization across the contact zone, despite the absence of physiological, anatomical or genetic barriers to such hybridization.[8]
Also see Two species of crow evolving ... on this possible crow speciation in process, apparently due to coloration:
quote:
"Only two major effect genes which together encode the feather colour differ sharply on either side of the hybrid zone - the gray alleles are not found to the west of the zone and the black allele is absent in the eastern region," Wolf said.
Breeding populations apparently separated by sexual/mate selection.
quote:
Koinophilia is an evolutionary hypothesis proposing that during sexual selection, animals preferentially seek mates with a minimum of unusual or mutant features, including functionality, appearance and behavior.[1][2][3][4][5][6] Koinophilia intends to explain the clustering of sexual organisms into species and other issues described by Darwin's Dilemma.[3][4][5] The term derives from the Greek, koinos, "common", "that which is shared", and philia, "fondness".
Natural selection causes beneficial inherited features to become more common at the expense of their disadvantageous counterparts. The koinophilia hypothesis proposes that a sexually-reproducing animal would therefore be expected to avoid individuals with rare or unusual features, and to prefer to mate with individuals displaying a predominance of common or average features. ...
This Koinophilia is similar to what I proposed for sexual selection in Sexual Selection, Stasis, Runaway Selection, Dimorphism, & Human Evolution and my discussion on the causes of stasis in breeding populations living in stable ecological habitats.
This Crow mate selection is similar to the overlap of the end of ring species like the Greenish Warbler, another place where the definition of species is problematic.
For the record, the crows are listed in List of Corvus species as different species, likely because they were classified before genetic information was available, based on appearance and behavior.
Note that you should be delighted that the hooded crow seems to be a product of isolation and gene loss promoting a phenotype that was not apparent in the parent population. The loss is a mutation, of course.
Enjoy

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RebelAmerican☆Zen☯Deist
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This message is a reply to:
 Message 637 by Faith, posted 07-02-2019 4:43 AM Faith has not replied

  
RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 708 of 785 (857073)
07-05-2019 9:36 AM
Reply to: Message 704 by Faith
07-05-2019 8:20 AM


Re: Flood stuff

This message is a reply to:
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RAZD
Member (Idle past 1654 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 715 of 785 (857293)
07-07-2019 12:10 PM
Reply to: Message 714 by dwise1
07-07-2019 11:21 AM


Re: Creationist mindset
That doesn't mean you can't be better.
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