Hi Faith, hope you are feeling better. I've been in bed with a sever cold\flue\allergy (not sure which, but headaches and coughing, so I'm just catching up on these threads).

[qs]Apparently breeding can result in speciation. At least there is one known instance, according to Wikipedia on Speciation: [/qs]

There are many instances of speciation known about, but that is not one of the traits that are normally considered desirable during breeding (because you may want\need to use hybridization).

I'm moving my comments from [mid=757706] on the [tid=17593] thread here as they are more pertinent to this topic:

<fieldset>HI Faith,

[qs]I have to stop here in your voluminous post.[/qs]

Yes, we both tend to get verbose. If you like we can break it up into multiple posts if length becomes a problem in covering the topics.

[qs]Selection certainly applies here as Darwin himself was doing the selecting, at times rather drastically isolating a trait of his choosing and breeding to enhance that trait until the bird was dominated by it to the exclusion of other characteristics. If there was some reason in nature for the development of the same trait you would see Natural Selection at work to the same end.[/qs]

Agreed, but I would also note that the result of natural selection are individuals within a species that are adapted to survive and breed in their ecology, while human selection is for traits that appeal to humans, whether they have any survival or  reproductive value, and for that reason a lot of domesticated breeds of pigeon, horses, sows, pigs, dogs and cats have traits that would be disadvantageous in the wild or even lethal without human medical interference.  Different purpose &rarr; different effect.

[qs][qs] His insight was that the selection process occurred naturally, where animals that survived and bred passed their genes (that enabled them to survive and be selected by mates for breeding) to the next generation. [/qs]

Yes, this was his insight but he didn't have the knowledge that would tell him that the changes that occur through selection, natural or artificial, are limited by the fact that selection eliminates alleles in the process of developing new phenotypes. Eventually the new breed or type may be quite strikingly different from others of its kind but it will of necessity have much less genetic ability for any further evolution. ... [/qs]

You've been told and shown and shown and told that this is not true, this belief of yours that no new alleles are produced. There are some examples in other replies to you.

Curiously I think Zatara had a good new example in [mid=757378]:

[qs]Anyone who has raised identical twins has observed the dramatic effects of mutation in just one generation. Their twins may have started out with identical DNA, having come from the same zygote; however, in just nine months in utero the mutations have yielded differences noticeable to all but a casual observer. [/qs]

Their DNA came from the same original single celled zygote, but during fetal development the process of cell division and duplication and selection for which aspects of their DNA is expressed becomes different as different mutations are incorporated into the development of the individual fetuses -- where did those differences come from if not mutation Faith?

<h2>Greenish warblers again</h2>

[qs] ...  When a trait is selected its genotype is also selected, and alleles for other expressions of the same trait are soon eliminated from the population of birds from which the trait is being bred. If the selection continues generation after generation a point may be reached where ONLY the alleles for the chosen trait are present, all others having been left behind in the original population. if this goes on long enough in nature it is easy enough to see how a subpopulation could develop inability to interbreed with other populations of the same Species, from sheer genetic mismatch ... [/qs]

Curiously we can actually examine this claim in  more detail with the [url=http://www.zoology.ubc.ca/~irwin/GreenishWarblers.html]Asian greenish warblers[/url] [i] (Phylloscopus trochiloides)[/i]:: different traits in each subpopulation, traits that govern plumage variations and mating and call song variations:

[quote]Genetic data show a pattern very similar to the pattern of variation in plumage and songs. The two northern forms [i]viridanus[/i] and [i]plumbeitarsus[/i] 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.[/quote]

Note that it is [i]hypothesized[/i] that the original parent population that these varietals all descended from was "once confined to the southern portion of their range" ... SO: if your hypothesis were true (that varietals only arise by the loss of alleles in the descendant populations) that they would [i]KNOW[/i] that one population was the source of the others as it would still have [i]ALL[/i] the alleles of [i]ALL[/i] the varietals.

Sadly (for you), the genetic evidence tells us that no one population has more alleles than the others, to say nothing of combining all of them: there isn't one population that has all the alleles of all the variants.

Further note that none of the populations are completely isolated from the others, that there are small overlapping zones between them:

[img]http://www.zoology.ubc.ca/~irwin/images/greenish%20warbler%20map.jpg[/img]

So there isn't complete genetic isolation and gene flow is possible from one end to the other. This gene flow is limited by the distance the individual birds will travel from where there were born to where they nest and mate and rear young during their lives, so gene flow from one end to the other could take several generations.

Now I would expect a corollary of your hypothesis (that divergence from a parent population results in loss of alleles) to be that when the populations converge in an overlap zone and interbreed that the alleles would be recombined in the hybrid zones and tend to restore the number of alleles from the original parent population in the hybrid population.

Your problem is that there are four such zones -- (1st) between [i]viridanus[/i] and [i]ludlowi[/i], (2nd) between [i]ludlowi[/i] and [i]trochiloides[/i], (3rd) between [i]trochiloides[/i] and [i]obscuratus[/i] and (4th) between [i]obscuratus[/i] and [i]plumbeitarsus[/i]. Which of these is your parent population with the more complete set of alleles?

Additionally, with gene flow from each of these hybrid zones to each neighboring varietal zone, we would expect (from your hypothesis) that the intermediate varietals would be hybrids between each of their end (hybrid) zones, ie that [i]ludlowi[/i] would be a hybrid between the 1st and 2nd zones, that [i]trochiloides[/i] would be a hybrid between the 2nd and 3rd zones, and  that [i]obscuratus[/i] would be a hybrid between the 3rd and 4th zones, and continuing this reasoning we should see  [i]trochiloides[/i] as a hybrid between [i]ludlowi[/i] and  [i]obscuratus[/i], that even if [i]trochiloides[/i] was not the original parent population posited in your hypothesis that it should, via convergence of the populations, have characteristics more like this posited parent population that the other varietals.

That we do [i]NOT[/i] see the hybridizing restoring the full allele distribution to one of these populations means one of two things:

[list=1][*] that the posited parent population with a full mix of alleles available is not as robust and able to survive and breed as the daughter populations each with less alleles than this (which doesn't fit with your hypothesis)... or
[*] that this posited parent population with a full mix of alleles never existed, and the varietals are due to mutations along the way as they spread out, variations that spread back and forth with gene flow without being combined into one master population that would have all the alleles.[/list]

Can you explain how this evidence does not invalidate your hypothesis?

Evolution with mutations and natural selection explains these population variations without the problems your hypothesis has.

<h2>Pelycodus again</h2>

Now I want you to look at the bottom line in this graph, below where it says [i]P.ralstoni[/i]:

[img]http://www.don-lindsay-archive.org/creation/pelycodus_work.gif[/img]

Under the "P" there is a thicker line, and this designates where more of the population is found, with the thinner lines to each side designating the variation in the population to each extreme right and left. You will note that these thicker lines stagger back and forth a fair bit as you go up in the diagram to younger populations.

If I draw a vertical line from the right end of the bottom population (below "[i]P.ralstoni[/i]) ...

[list=a][*] as I ascend to younger populations where do the new traits to the right of this line come from?
[*] when I get to [i]P.trigonodus[/i] the whole population is to the right of [i]P.ralstoni[/i]: where do the traits of that population come from?[/list]

Remember that the overlaps from level to level, showing more than 50% of these populations have identical traits, is an indication that they represent the same species/clade breeding population changing over time and adapting to the ecology.

Next, If I draw a vertical line from the right end of [i]P.trigonodus[/i] I can repeat my questions:

[list=c][*] as I ascend to younger populations where do the new traits to the right of this new line come from?
[*] when I get to the group just below "[i]N.venticolis[/i]" that whole population is to the right of [i]P.trigonodus[/i]: where do the traits of [i]that[/i] population come from?[/list]

This latter group is now [i]twice[/i] removed from the base population that we started with: how do you explain their traits with your hypothesis?

Further, if I now draw a vertical line from the left end of  [i]P.jarrovii[/i] down, then according to your hypothesis that alleles are lost, then [i]ALL[/i] the alleles expressed in the base population to the left of this line are now apparently lost in this descendant population, but extending that line up we see traits similar to the original traits returning to the point where [i]N.nunienus[/i] seems to recapture most the original traits.

Note that the traits involved here are size related traits (size of bones, teeth, body mass, etc), and other traits (coloration, vocalization, etc) are not included so that younger populations would still not appear like the base population even though they now share size related traits.

How can you explain this with your hypothesis? Can you explain how this evidence does not invalidate your hypothesis?

Note that if you posit that traits can become hidden and then re-expressed later when conditions suit (as you have posited hidden traits that become expressed, as I expect you to claim for traits to the right of my lines - and as you [i]have[/i] claimed for the foxes - that this invalidates your claim that the traits are lost and thus results in a death spiral of lost traits).

Evolution with mutations and natural selection easily explains these population variations without the multiple contradiction problems your hypothesis has.

<h2>Foxes again</h2>

[qs]You say nothing about artificially induced mutations here, and there is absolutely no need for them. This change was possible because the genetic material for the chosen traits was already present in the fox genome and could be selected over several generations. This is how all breeds of animals were originally developed, by selection of the traits desired by the breeder, selection meaning basically reproductive isolation of the individuals with those traits. ... [/qs]

Not quite correct Faith -- the [i]ONLY[/i] trait selected was tameness, and this was done specifically to make the foxes easier to handle on the fox farms where they are raised for their desired black lush fur. That white spots developed is contrary to what the desired result was.

The reason is that tameness is related to adrenalin levels and adrenalin is a hormone that affects fetal development paths, including fur color, ear and tail characteristics.  This is about mutations that occur during fetal development because of the different hormonal environment for the fetus. Mutations that affect the timing of development.

<h2>and Bacteria again</h2>

[qs]Bacteria don't function genetically or reproductively the way sexually reproducing animals do ... [/qs]

Actually the point of bacteria is that cell division and multiplication during fetal development is the same process that bacteria use to reproduce. Thus bacteria developing new traits and fetal development changing to develop new traits (the fox fur, ears and tail traits) are the same process - adaptation to a different chemical environment with new mutations.

<h2>denial is not evidence</h2>

[qs] ... and I refuse to accept such "evidence." But of course that's the best you can do to answer my obvious points, isn't it? [/qs]

Curiously I think I (and others) have done more than answer your "obvious points" and raised (again) legitimate points that you have yet to answer. Sadly I expect your "answer" to be more denial rather than confronting the evidence.

There is a lot more evidence that supports evolution, evidence of mutation providing new alleles, evidence of selection and drift causing an accumulation of new traits in species over time.

There is no evidence that traits are [i]only[/i] lost and never gained, but there [i]is[/i] evidence of traits being gained.

Enjoy</fieldset>

[qs]Thought I'd be able to post today but my eyes are hurting, so I have to put it off again.[/qs]

sad to hear, I have another friend with macular degeneration, it sucks.

Enjoy

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