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Author | Topic: How do you define the word Evolution? | |||||||||||||||||||||||||||||||||||||||
PaulK Member Posts: 17822 Joined: Member Rating: 2.2 |
What your argument misses is that overall diversity can remain constant - or rather fluctuating around a mean - even if your argument were entirely correct.
You also miss both the evidence and the theoretical considerations that destroy your argument but you've been ignoring those all along.
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Taq Member Posts: 9973 Joined: Member Rating: 5.7 |
Faith writes: Sorry, my premises are ironclad and never disproved. Loss of genetic diversity is the necessary condition for evolution of new phenotypes. Your premise is disproven by the emergence of the new allele by random mutations prior to it replacing the old allele. This process repeats over and over, producing macroevolution.
This produces new phenotypes by losing the alleles for other traits. Mutations produce those phenotypes, not natural selection. Natural selection can only make those phenotypes more or less common within the population.
Since loss of genetic diversity is necessary to produce it, each new species has less genetic diversity than the last, and after a series of such population splits it's no wonder if ability to interbreed has been lost by simple genetic mismatch. Mutations increase genetic diversity. Your argument is disproven.
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Taq Member Posts: 9973 Joined: Member Rating: 5.7 |
Faith writes: And I define the Kind as the boundary at which genetic diversity has been reduced to the point that no further evolution is possible. Then there are no kinds according to your definition since mutations increase genetic diversity in every generation. Take the cheetah as an example. A population bottleneck reduced their genetic diversity, but that diversity is increasing with every generation due to accumulation of new mutations. Edited by Taq, : No reason given.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
If you mean by "overall diversity" the genetic diversity in the Kind as a whole, yes of course, and I point that out when I think of it. My argument is about what happens as necessary result of evolutionary processes, selection and isolation in particular. Evolution is what requires reduction of genetic diversity. All forms of it do, even drift, but I usually focus on the faster versions such as population splits which can occur over a matter of years.
Sorry I've missed nothing that would destroy my argument.
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Taq Member Posts: 9973 Joined: Member Rating: 5.7 |
Faith writes: My argument is about what happens as necessary result of evolutionary processes, selection and isolation in particular. You are leaving out the process of mutation which is why your argument doesn't work.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
No, I'm not leaving them out, I've accounted for them.
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Taq Member Posts: 9973 Joined: Member Rating: 5.7 |
Faith writes: No, I argue rightly that any additional genetic diversity must be reduced or lost to produce a new phenotype. Once that new phenotype is fixed in the population then mutations will occur in that fixed allele producing more genetic diversity.
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Taq Member Posts: 9973 Joined: Member Rating: 5.7 |
Faith writes: No, I'm not leaving them out, I've accounted for them. Where?
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
No, it IS the selection that produces the new phenotypes. It doesn't matter what the source of the genetic material is. Most of it is built in and not produced by mutations but it doesn't matter. You cannot get a new phenotype unless you lose the genetic material for other phenotypes. This is wlel known in domestic breeding and the same thing has to happen in nature whenever you get a new species from a population split.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
Faith writes: No, I argue rightly that any additional genetic diversity must be reduced or lost to produce a new phenotype. Once that new phenotype is fixed in the population then mutations will occur in that fixed allele producing more genetic diversity. That's pure wishful fantasy. The production of new species is a lot faster than the ToE says, and you don't get beneficial mutations at any rate that would make a difference. And if you did there couldn't ever be a stable domestic purebred and the cheetah would long since have been rescued from its genetic depletion. It doesn't happen, it's sheer theory/fantasy. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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PaulK Member Posts: 17822 Joined: Member Rating: 2.2
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quote: No, I mean the genetic diversity of species.
quote: Which is exactly where my point comes in. Your claim of a necessary long-term decline is unsupported - and always has been. Ranting falsehoods is not going to change that.
quote: It does not require an overall, long-term ongoing reduction in diversity. And you have never come up with a sound argument to the contrary.
quote: The fact that your only examples of "genetic depletion" are species that have undergone severe bottlenecks destroys your argument to give just one example. The fact that these bottlenecks have not produced new species and even the aggressive selection of artificial breeding has not hardly helps.
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Taq Member Posts: 9973 Joined: Member Rating: 5.7
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Faith writes: No, it IS the selection that produces the new phenotypes. Selection can only select for phenotypes that already exist. Mutations are responsible for the creation of those phenotypes.
Most of it is built in and not produced by mutations but it doesn't matter. Last I checked, humans don't have the DNA needed to give birth to chimps. No genome has the ability to produce all known species by the processes you are describing. No mixture of human alleles will produce an elephant. In order to have both elephants and humans you need different DNA sequences, and that's what mutations produce.
You cannot get a new phenotype unless you lose the genetic material for other phenotypes. I already disproved that claim. In the pocket mouse there was a gain of a phenotype from mutation, not from a loss in genetic material. "Rock pocket mice are generally light-colored and live on light-colored rocks. However, populations of dark (melanic) mice are found on dark lava, and this concealing coloration provides protection from avian and mammalian predators. We conducted association studies by using markers in candidate pigmentation genes and discovered four mutations in the melanocortin-1-receptor gene, Mc1r, that seem to be responsible for adaptive melanism in one population of lava-dwelling pocket mice."Just a moment... This new phenotype was not produced by loss of alleles. This new phenotype arose through mutation within existing alleles.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
Breeding and ring species are excellent examples.
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Taq Member Posts: 9973 Joined: Member Rating: 5.7 |
Breeding and ring species are excellent examples. Mutations occur in populations bred by humans, and they produce new phenotypes.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
To get the black pocket mice does mean losing the alleles for the light colored ones and vice versa. The same thing happens with the famous moths. The genetic material for the other color is still present here and there in the population so that they can switch back when the selective pressures change. If you're arguing for mutations that show up just in time to save the sinking ship you're talking Lamarck not Darwin.
Edited by Faith, : No reason given.
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