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Author Topic:   The "Logic" of the creationist....
Rationalist
Inactive Member


Message 25 of 69 (15566)
08-17-2002 12:09 PM


FK:
Where do these numbers come from, John Paul?
John Paul:
The 1667 comes from 10 million years (divided by) 300 generations for 1 beneficial mutation to become fixed in a population (divided by) 20 years per generation.
And what about all of the other ambient mutations in the genome. Are we to believe that of all of the mutations that are introduced into the gene pool of a species, only one at a time can become fixed?
Is this based on Haldane's faulty replacement model by any chance?

Replies to this message:
 Message 26 by John Paul, posted 08-17-2002 12:34 PM Rationalist has not replied

  
Rationalist
Inactive Member


Message 28 of 69 (15603)
08-18-2002 10:38 AM


quote:
John Paul:
A mutation, any mutation, has a better chance of getting lost in a population than it does becoming fixed.
If this were not true, the genetic load of mutations would become somewhat of a problem.
quote:
As we know most mutations are either harmful or neutral, why would these mutations even be selected?
Neutral mutations aren't, and negative mutations are actively removed from the population through the disproportionate death of those indivudals who have them.
quote:
Beneficial is a relative word as there is no way to predict what would be selected for at any point in time.
Certainly there is. A change in the survival traits of an organism which gives it an advantage relative to its peers will be selected. These can include features such as better camoflage, smaller size to avoid detection of predators, larger size to discourage predators, etc. etc.
quote:
What may be beneficial for one generation may not be beneficial for future generations
And conversely, what may be beneficial for one generation will commonly be beneficial for future generations.
quote:
However I am open to any evidence that shows that more than 1 beneficial mutation can become fixed in a population in a shorter timeframe.
http://www.gate.net/~rwms/haldane.html#solutions
The basic criticism of Haldane's supposed "dilemma" is that it is an outdated and basically invalid model of how population genetics works.
The specific problem with it is that it posits a 'replacement cost' that assumes that for each mutation to be fixed in a population, the rest of the individuals in the population with the existing version of the gene must be eliminated.
This scenario, however, is only valid in instances where the selection pressure on a particular gene is very very high, as in the case of rapid environmental change.
The more common scenario is that of a large number of mutations entering the genome, being winnowed to a very small number first by sexual selection and natural selection, and becoming fixed in "pipeline" fashion over the course of a few dozen generations. In this manner, each generation fixes a new set of mutations which are the end product of a much larger set of raw mutations which entered the genome many generations ago.
This is how real ordinary population genetics works, and it is the basis for the modern theory of evolutionary genetics, and results in a vastly larger number of differences than Haldane's faulty model.
quote:
Also becoming fixed might not even be enough. What happens when an organism with this new mutation mates with an organism without it?
This is a non-sequitur. A fixed gene is one in which only one version of a particular nucleotide in a population exists.
quote:
And yes the 1667 is derived using Haldane's dilemma. If you think it is faulty perhaps you should start a thread to explain why you think it is.
Haldane's model is kept alive only by creationists. Why don't you spend some time making the argument as to why creationists seem to ignore the rest of the body of population genetics since Haldane, and the obvious problems with his early model.
[This message has been edited by Rationalist, 08-18-2002]

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Rationalist
Inactive Member


Message 45 of 69 (15693)
08-19-2002 11:29 AM


quote:
According to NDT an original LCR16a gene region (where did it come from, anyway?) duplicated several times. Duplications give rise to IDENTICAL regions and if it encodes a protein it will specify the same protein. After duplication the genes/DNA regions are redundant. Redundant regions accumulate mutations at a neutral rate. Mutation rate is approx 10exp(-10) - 10exp(-9)/nucleotide/year. In the gene random accumulation of mutations will occur with an incidence of approx 1.5 exp(-6). That is 1.5-15 nucleotides per million years in this approx 2000 bp gene. In 6 million year there will be only 9-90 nucleotides to be different. That is a lousy 0.5-5 promille. It doesn’t matter whether selection acts or not, since the generation of mutations is a random process (according to NDT). It indicates that you need a very large population, and it has been demonstrated with the ZFY region (that provides another major problem for evolution theory) that only minor populations of humans had to be present.
The mutation rate is proportional to population size, which varies over time. Therefore a fixed rate of nucleotide substitution is only valid given the size of the present population.
In addition to this, changes in the size of the population have a substantial effect on mutatation and fixation. A population typically doesn't stay constant over 5 million years.
John Paul:
You seem not to be able to explain why Haldane's replacement cost theory ignores soft selection and multiple simultaneous mutations undergoing selection simultaneously? Why should we bother with your argument about a particular number of mutations if you can't even support the process by which you arrived at this number?
[This message has been edited by Rationalist, 08-19-2002]

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Rationalist
Inactive Member


Message 68 of 69 (16830)
09-07-2002 2:42 AM


The "Devolution" of JP..
From reading the posts, I would characterize debates which JP largely proceed as follows:
JP: Evolutionists don't have a leg to stand on. What about X?
EV: Well, X seems to be a natural component of evolution.
JP: That is ridiculously naive. You believe that simply because you are a brainwashed evolutionist robot. You know that creationist Y said this about X. It is proven.
EV: Creationist Y is wrong because if these various problems with his argument...
JP: I can't believe how stupid you are. You honestly believe all this crap the evolutionists are shoveling. You are a mental pygmy. What about the fact that evolutionist Z said "Insert out of context quote here".
EV: That quote was taken out of context to make it seems as if the individual believed something he didn't. As to your other points..
JP: The reason you don't agree with me is because you are obviously too stupid to see my point. I have clearly proven you completely wrong, and if you weren't a blithering gibbering idiot, you would admit that I was right.
EV: Usually responds in kind..
JP: You are too feeble minded to understand spetner, behe, (etc. etc.) They have proven everything and you have proven nothing. You're an imbecile, a mental midget without a clue. Your understanding of the issues is dwarfed by my own, and you simply just don't realize it. Your arguments are that of a four year old. My Dog is smarter than you, and so is my parakeet, and my pet goldfish. You just don't have two neurons to rub together my friend.
[This message has been edited by Rationalist, 09-07-2002]

Replies to this message:
 Message 69 by Fedmahn Kassad, posted 09-09-2002 10:01 PM Rationalist has not replied

  
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