Evolution Requires Reduction in Genetic Diversity

Exactly. And alternatively if creating species is about stomping out diversity, how is it that border collies, Danes, poodles, Labs (of all colors, world's best non human companions), Chihuahuas, bulldogs, spaniels(all types), Terriers, Shih Tzus, and yes, those mutated dachshunds and countless others are all of the same species.Or this: If you can have mutations and still be human, then eliminating or preventing such variation or diversity is not a part of forming a human species.Seriously, is there really anything left of this "End of Evolution" stuff? Because absent some new argument, I think a mud hole has been stomped in 'Evolution Requires Reduction in Genetic Diversity'.

I recall you saying that your knowledge of genetics is rudimentary. I would have to take the above as a mere statement of belief and not an argument or any kind of informed statement of opinion. Let's consider your proposition for a bit, because it seems that distinguishing between breeding and speciation is the single issue here. Perhaps you can at least appreciate why others are reasonable in giving your idea fairly short shrift.A border collie breeder is going to reject offspring that doesn't fit a very tight description of what constitutes a border collie. We would expect that when the breeder is successful, the resultant pups would not possess any visible or behavioral variant traits that don't meet the border collie specification. And yet even the rejected dogs are of the same subspecies Canis lupus familiaris as the acceptable collies.By contrast, natural selection doesn't act on traits that don't affect survival to sire/bear/rear puppies. This means that the end product of evolution can produce a population having tremendous variation. Any mutation that does not affect survival will not be selected against. There is no end goal to make a dog having any exact specification.Evolution over hundreds of thousands of generations or more is what produced almost all of the variation in the animals that constitute the single sub species that we call dog. Note that the dog sub species includes huge variation.Yet in just a few generations, a breeder can produce a tight specification like a border collie. Surely that's ample evidence that evolution and breeding do not work the same at least in the way relevant for this discussion. Absent a showing or argument that different selection methods employing different selection criteria and operating over vastly different time scales produce the exactly the same result, the idea that breeding and evolution processes operate the same is unreasonable.In particular, over and expanded period of time, we can anticipate generating some beneficial mutations randomly. In the time period over which man breeds animals, we would not expect that to happen.Edited by NoNukes, : No reason given.

The new diversity need not be of the same kind that is being subject to selection to create the species. For example if evolution were creating a dog species, mutation could produce in the population of dogs any of the variations that currently exist in the sub species we currently call dogs without undermining the process of creating a species That is one distinction between evolution and breeding. In my opinion, Percy's analogy has the potential to cloud the issue. The stream of water coming in represents a torrent of mutations of various types. Correcting the analogy to drive home that point would probably make it more confusing. But Percy was right about the particulars he discussed with the analogy. Speciation can occur without any new mutation events, but mutation is the source of the variety in the ancestor populations. Any suggestion by proponents of evolution that the mutations occur on time is mistaken. However an existing neutral mutation can become a beneficial if environmental conditions change. Yes, but that's because we consider variations to be things like new fur color and new ear shapes, which might well be produced by simply partitioning off the various genes that control fur color. That's not really speciation.Let's also recall that species is not a perfect classification. Some separately named species are separated on fairly dubious grounds. There are people who would label the different races as different sub species despite the fact that race itself is a dubious characteristic. Let's instead consider speciation that truly represents evolutionary distinctions. Not necessarily.The loss of ability to interbreed is not directly related to reduced genetic diversity. For example, the Chinese population is much more homogeneous that the US population. Yet we know of no lack of fertility between any of the races present here and the Chinese population. We also know that dogs breeds are inter-fertile.The loss of ability to interbreed generally comes from new variations in separated populations. I'd suggest that those variations are generally mutations, but I haven't actually thought that proposition through. That's fine. In fact, that's great. Disputing an old idea is what produces an interesting start to a thread. Now bring some arguments that might convince the less stubborn among us. Sorry. I didn't explicitly state the conclusion. The point is that we could easily produce a distinct result in a relatively small number of generations through eugenics. Breeding is not the same as evolution.

Sorry for not responding to this in my last message: You can pick the measure. Is the set of inter-fertile bears more or less diverse than the set of currently existing inter-fertile humans? Are grizzly bears more or less diverse than some sub grouping of humans I might elect?

You are the one who introduced grizzly bears into the discussion. I'm trying to demonstrate that diversity in the genetic makeup of grizzly bears compared to humans is irrelevant. It seems you agree. I'm not going to get picky about whether your concept is actually a model until you write a scientific paper describing the concept. You are free to take up that issue with whoever raised it. What I will suggest is that I've already provided several examples that indicate that your concept does not model the processes which are claimed to be part of the theory of evolution.I agree that under your 'model' that evolution is impossible. On the other hand, your 'model' is little more than an assertion that evolution cannot happen. Edited by NoNukes, : No reason given.

Perhaps this exception for 'identical' twins is not universalIdentical Twins' Genes Are Not Identical - Scientific American

quote:

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Geneticist Carl Bruder of the University of Alabama at Birmingham, and his colleagues closely compared the genomes of 19 sets of adult identical twins. In some cases, one twin's DNA differed from the other's at various points on their genomes. At these sites of genetic divergence, one bore a different number of copies of the same gene, a genetic state called copy number variants.

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I apologize for the lack of precision caused by my attempt to be tactful. Your presentation here suggests that you know 'jack doodly squat' about genetics. Your personal statements of doubt about how mutations contributed to evolution are of zero persuasive weight.Is that better?Edited by NoNukes, : No reason given.Edited by NoNukes, : No reason given.

Faith's statement while badly phrased, gets at some truth that isn't expressed in your statement. If a new trait occurs in one individual, it can still be passed to offspring without being selected for. As long as the trait is not subject to purifying or negative selection, the trait can drift through the population without contributing to speciation, at least until something changes the status of the trait from neutral to beneficial or deleterious. Excellent point. I don't recall anyone else has stated this as clearly.

I don't believe that to be correct usage of selected for.We cannot say that an individual with trait Y is selected for simply because the individual manages to reproduce and pass on his traits. What if of a group of similar individuals with the trait, the rate of survival is substantially the same as for a group of individuals without the trait. It would be incorrect to say that individuals with trait Y are selected for or to say they are selected against. Neutral traits are not selected for, yet they can appear and become fixed in the population.Further if a trait does contribute to or detract from the survival of individuals to propagate heirs on a statistical basts, I don't think it is incorrect to speak of the trait itself as being selected for or against at least with respect to the general phenotype. Yes, selection does operate on entire individuals, but the result is to alter the frequency of traits in a population.Example: Are individuals with sickle cell anemia selected for here in the US where there is no malaria? I don't think it makes any sense to say so, yet parents do pass the trait onto their offspring.Edited by NoNukes, : No reason given.

Say what? In what sense would that ape not have been 'real' mom?

I am trying to decide. If you could humor me a bit, would you use the terminology 'selected for' in a sentence that makes sense to you?

Thanks Percy, you've help me avoid posting a rather testy reply. I don't see that I'm posting anything that several other posters don't manage to post without losing their cool, so I'm going to semi-lurk mode for awhile.

I disagree.New dog breeds are less diverse than the entire subspecies Canis lupus familiaris because breeders cull diverse offspring during breeding. Any single breed would have to be less diverse than the sub species because the sub species includes the new breed plus every other dog that has ever walked the face of the earth. For example the set of human beings with blond hair, blue eyes, and height over 6 feet tall is less diverse than the species Homo sapiens.My statements about the dog sub species were perfectly clear and correct. In a previous post I even named the sub species. I won't pillory Faith for not following my meaning despite the fact that I used the terminology correctly, but I'm certainly not going to accept any responsibility for her error.Who erred is beside the point anyhow.The inescapable conclusion is that dog breeding produces neither new species or nor new subspecies. It produces only inter-fertile offspring of the same sub species. In other words, even after acknowledging her mistake and blaming me for it, Faith hasn't noticed that the argument is over. If in fact speciation is possible, something Faith has yet to dispute, dog breeding does not produce speciation.

Diversity can be added before and after and possibly even concurrently with selection. It can triggered either because a new mutation is immediately beneficial or because an environmental change causes a pre-existing mutation to provide a new advantage.Edited by NoNukes, : No reason given.

I think she actually did imply this a long time ago. This thread has had a number of jumping off points, because boiled down to its essence the entire support for the premise of this thread is the assertion that that mutations don't contribute variation for evolution to progress.Initially Faith said that evolution was exactly like breeding. Later she acknowledged that evolution was only analogous to breeding. That's failure one. You cannot prove anything by arguing from analogy. Such arguments always break.Faith has also has said that she isn't talking about speciation. If that's true, then who cares about the rest of the argument. This thread is not about evolution at all. Failure two.Faith acknowledges the possibility that some breeds may have been created around mutation, although she doubts that to be the case. More importantly though, she complains about the small number of cited examples (as if...). However the thread says that evolution 'Requires' reduction in Genetic diversity. 'Requires means no exceptions. In other places Faith talks about the 'General Rule'. But a single exception is enough. Failure three.Faith says that mutations interfere with speciation because they delay creating a highly specific phenotype. On the other hand, she acknowledges the great variety in human beings and dogs. But all humans are in one species as are all dogs. In other words, nature's species do not consist of highly specific phenotypes such as toy poodles. The breeding analogy then is totally broken and the argument that breeds represent some loss of diversity from the species is also demonstrably wrong. Failure and jumping off points number four and five.Dr. Adequate describes the special breeding procedures for Curly cat that involved breeding the original curly cat and descendants with cats outside of that small circle. Faith noted that once the forced outbreeding stopped, then diversity would decrease. Faith failed to observe that the matter of what cats the curly eared type bred with was totally controlled by human beings.Of course, out in the wild, the only thing that would determine which cats a curly eared cat would breed with would be the forces of natural selection. Absent a deliberate, guided and enforced policy, no exact phenotype results. Failure/Jumping off point six.And of course, none of us agree with Faith because we're all too stupid to follow her logic. I'll admit that I have picked at a few posters over some minor points, mostly out of boredom with the main line of argument, but the fact is that all of the participants understand Faith's posts. It's just that the posts are devoid of any persuasive reasoning and full of errors illogic. This kind of reasoning would not persuade a drunk to follow you to a keg of beer.I stop here not because I have listed all of the illogic I could cite, but because these examples ought to be enough. I was never under that impression.Faith's alternate view of evolution is contained in Genesis 2. "Thus the heavens and the earth were completed in all their vast array." In other words, there is no evolution. Mutations generate only disease and trash. There is only breeding to form less diverse critters from the original created kinds, those kinds having super, packed genomes containing all variety possible. The creation of these kinds was completed before God rested from the unimaginable exertions involved with creating an entire universe in only six days. Yes, Percy, that's it. Edited by NoNukes, : Remove sentence that suggests dogs and people are in the same species.Edited by NoNukes, : No reason given.Edited by NoNukes, : No reason given.