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To: gore3000
You are misreading the article you cite:

The problem with the old studies is that the methods did not recognize differences due to events of insertion and deletion that result in parts of the DNA being absent from the strands of one or the other species.

No, you're misreading it. Britten came up with a more accurate figure for the differences in sequence. He was not trying to measure the number of mutations needed to produce those differences in sequence.

What the above means is simply that because of deletions in each species, the strands selected did not align properly, hence a simple 'alphabetic' comparison of the sequences gave a wrong number. What Britten did, and the reason he revised the figures, is he properly aligned the strands according to what was the purpose of them. In this way he came up with the more accurate 5% number.

But the DNA hybridization technique "involved collecting tiny snips of the DNA helix from the chromosomes of the two species to be studied". Now, stop & think what this would mean if you had a child that doubled its parents' chromosomes (ex.: from 10 to 20): The hybridization technique would not detect any difference between the two genomes! It would "think" it was just seeing twice as many snips of the child's DNA sample as it was "seeing" of the parent's sample, and would declare the genomes to be exactly 0% different.

In reality such a doubling of the number of chromosomes required one mutation, but the newer sequence comparison technique would correctly conclude that there was a 50% difference in total sequence between parent & child. See? The two techniques are measuring two different things.

Now as to neutral mutations, they just cannot spread throughout a species - according to studies made by evolutionists themselves when they were trying to solve the problem posed by genetics. The basis of population genetics is the Hardy-Weinberg principle which says that in a stable population the genetic mix of the population will remain stable absent any genetic advantage of a particular genetic makeup. What this means is that a neutral mutation in a population of 1 million organisms will continue to be in only 1 millionth of the population if it is neutral. In fact it will likely dissappear completely due to chance (if you play a game at odds of 2 to 1 with two dollars long enough you will lose both dollars), so neutral mutations cannot be in any way responsible for these differences in any significant way.

Please see this page from Kimball's Biology Pages. Scroll down to the section titled "When the Hardy-Weinberg Law Fails to Apply". Then find the subhead "Genetic Drift:

Genetic Drift

As we have seen, interbreeding often is limited to the members of local populations. If the population is small, Hardy-Weinberg may be violated. Chance alone may eliminate certain members out of proportion to their numbers in the population. In such cases, the frequency of an allele may begin to drift toward higher or lower values. Ultimately, the allele may represent 100% of the gene pool or, just as likely, disappear from it.

IOW, Hardy-Weinberg only helps you if you're talking about a species that does not separate into tribes, so it really is one huge interbreeding population. It might help you if we're talking about promiscuous ocean-dwelling fish, or birds that live in huge flocks, or modern humans, etc. But it does not help you with prehistoric humans.

Due to the above, yes, the differences are 5%. Yes, you need some 150 million mutations. Yes, mostly all of them have to be favorable to have survived.

In conclusion, no, no, and no.

41 posted on 02/05/2003 2:31:48 AM PST by jennyp (http://crevo.bestmessageboard.com)
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To: All
This thread won't last...
42 posted on 02/05/2003 7:02:40 AM PST by Condorman (Fact-based crevo threads have the life expectancy of a glass hammer.)
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To: jennyp; gore3000; Condorman; RadioAstronomer
Jenny,

That is gracious of you to point out that both of our math is in error! I still am not convinced that we should multiply the base pairs by .014 rather than .05. Still, I am willing to give you that one in order to move forward with the discussion.

I am convinced that whether there are 150 million base pair differences (my and g3K's number) or only 42 million bpd (your new number) between man and chimp, it is all but impossible for those differences to accrue in the alledged 10 million years. Large, long-lived, slow reproducing, low-offspring mammals just don't get their genome rearranged that fast.

You admitted, with your 42 million, that this would be one change fixing itself in the entire human genome every three months- and that was in FUNCTIONING GENES THAT ARE EXPRESSED! This does not seem realistic at all. Can anyone out there, crevo or evo alike, give us some insight on how long it takes a mutation to establish itself in even a small population of big mammals?

I went to that link you gave to g3K. Here, from your link are two examples of a LACK of gene change that I found very interesting....

Two examples of reduced polymorphism because of genetic drift:

By 1900 hunting of the northern elephant seal off the Pacific coast had reduced its population to only 20 survivors. Since hunting ended, the population has rebounded from this population bottleneck to some 100,000 animals today. However, these animals are homozygous at every one of the gene loci that have been examined.

Cheetahs, the fastest of the land animals, seem to have passed through a similar period of small population size with its accompanying genetic drift. Examination of 52 different loci has failed to reveal any polymorphisms; that is, these animals are homozygous at all 52 loci.

The lack of genetic variability is so profound that cheetahs will accept skin grafts from each other just as identical twins (and inbred mouse strains) do. Whether a population with such little genetic diversity can continue to adapt to a changing environment remains to be seen. "




Do you see the problem? You have to assume that the entire human race has fixed gene changes every three months for 10 million years, where as when we examine small populations of similar mammals we find that NO new genes have fixed themselves in the whole population (OR EVEN SHOWED UP IN A PART OF IT!!!) for a hundred or even thousands of years.

What we see in the real world just does not seem to match up with what evolution says would have to happen. If human genes mutated that much, the human race would be long extinct.
44 posted on 02/07/2003 8:33:25 AM PST by Ahban
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To: jennyp
No, you're misreading it. Britten came up with a more accurate figure for the differences in sequence. He was not trying to measure the number of mutations needed to produce those differences in sequence.

No. Let's look at how the original one was done:

The helix at this point would contain one strand from each species, and from there it was a fairly straightforward matter to "melt" the strands to infer the number of good base pairs.

As can be seen, this was a base for base comparison. No adjustments at all being made. Let's continue with the article YOU cited:

The problem with the old studies is that the methods did not recognize differences due to events of insertion and deletion that result in parts of the DNA being absent from the strands of one or the other species.

As can be seen, the original method did not take account of deletions which would put the DNA bases 'out of sync' after a while. This is why with greater knowledge of the genomes of both species (the complete sequencing of the human genome and some partial sequencing of chimps) Britten re-did his work. This time he took account of the deletions to more accurately match the genomes. That he 'refuted' his own work shows to me at least that there was good reason for him using this way of comparison as more accurate. (as to the article by John Pickerel whom I showed to be an evo hack with no credibility in post# 37 the less said the better).

As we have seen, interbreeding often is limited to the members of local populations. If the population is small, Hardy-Weinberg may be violated.

I am well aware of such statements being made by numerous evolutionists. I reject them because they contain numerous half truths. The first half truth (and a half truth is really a complete lie that because it contains and element of truth makes it more believable and thus a better sounding lie) is the implication that while Hardy-Weinberg can be violated in a small population, this makes it likely that a neutral mutation will take over the whole species from that blast off point is false.

Let's continue with the example of the population of a million in the species and let's say that the 'tribe' of 100 gets a neutral mutation and it spreads through it. Well, if the 'tribe' gets mixed into the general population (somehow, sometime, somewhere) then Hardy-Weinberg will be in effect again and those carrying the neutral mutation will be only 1/10,000 of the species and will remain so BECAUSE THIS MUTATION IS NEUTRAL. So again this neutral mutation will not take over the population or even become a significant part of the overall genome pool of the species. So this argument is bunk.

There is an even bigger problem though with these mutations becoming through a small inbred group a part of the genome pool of the whole species. It is a scientific fact that harmful mutations far exceed all other mutations. It is a scientific fact that inbreeding is harmful for the tightly inbred group. What this means is that the inbred group will become much less viable due to the inbreeding and that any neutral mutations within it will (if the group does not die off due to the harmful mutations) will dissappear when (or if) it joins the larger group and those harmful mutations show that the inbred group is less viable and less 'fit' than the main group.

What all the above amounts to is that you do need pretty close to 150,000,000 favorable mutations between man and chimp in just some 10,000,000 years of divergence (according to evolutionists). Problem is that we have not been able to find, in decades of experimentation a single such mutation creating the greater complexity needed to account for the differences between man and chimp.

58 posted on 02/09/2003 4:56:13 PM PST by gore3000
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