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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.

Frankly, I haven't been completely convinced that measuring an x.x% difference in human and chimp DNA is a particularly meaningful calculation in the first place. It makes for a great sound/word-byte, but what does it actually tell us that makes it worthy to include in the debate? People on the creo side love to toss out these numbers as a blow to evolution, but very few on either side are well-versed enough to understand what is actually being measured, and more importantly, the conclusions indicated by that number. (Although, while we're slinging calculations around willy-nilly, don't forget that whatever ulitmate number one arrives at for total mutational differences, that must be divided in half for rate of change calculations. After all, once the populations separated each began to drift independently.)

As jennyp has pointed out, there are several different types of differences that can be measured, from direct 1:1 comparisons straight up the line, to other analyses designed to account for insertions, deletions, reversals, and partial or complete gene duplications, in addition to other more exotic mutations.

I also wonder which chimp genome is being compared with which human genome. And how does this compare with a genome comparison between an African bushman and say, an Alaskan Eskimo? Or an Australian Aborigine versus a Brazilian Wari'?

But I think the larger point is this: No one doubts the similarity of chimps and humans. The physical and behavioral similarities are reinforced by genetic analysis, which points unquestionably towards common ancestry. The mechanisms of genetic variation are still under investigation, and the creo side, instead of triumphantly crowing about how these mechanisms couldn't possibly have caused X degree of diffence in Y amount of time, need to present evidence for something that could.

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.

No, 1 fixation every 3 months was for all types of mutation:

Let's see... 10 million years divided by 42 million mutations = 1 fixation every .238 years (3 months or so). But keep in mind that there are always many mutations at different locations in the genome working in parallel to get themselves fixed at the same time. How many? I have no idea, but if there were 1000 different alleles out there in the population at the same time that would mean an average allele would have 238 years in which to fixate for the numbers to work out. If there are 100,000 alleles then the average allele has 23,800 years to acheive fixation for the numbers to work out.

10 million years / 1.26 million coding base pair differences = 1 coding fixation every 8 years. Then multiply that by how many coding differences are working towards fixation at any one time. 10 mutations simultaneously working their way means each mutation has 80 years available to fixate, 100 mutations = 800 years per mutation, etc.

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....
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.

Which link is that? Could you provide the url? I couldn't find any reference to cheetahs at the Hardy-Weinberg page from Kimball.

That's an interesting finding, but I want to see more information about how exactly they were comparing these 52 loci. Were they using gel electrophoresis, or did they do actual letter-by-letter sequencing of 52 genes? It doesn't seem too surprising that an inbred population would all look the same if you don't sequence the DNA letter by letter. IOW, I think there are lots of sequence differences among cheetahs that are under the radar of that study - cheetahs are not all exact clones of each other.

Here's something interesting I found at another cheetah page:

There are seven recognized subspecies of cheetah, distinguished by subtle differences in their coats. The most striking is the king cheetah with spots that have been modified into wide discontinuous bars.

How can there be 7 recognizable subspecies if they're all exactly the same? (aHA!)

Also on that page, it describes the cheetah's habits. It seems they're very mobile - in fact cheetahs can't be housebroken because they don't stay in one place in the wild, so they have no real "home territory" to keep clean. I suspect that African cheetahs (the only population that survived after the bottleneck 10,000 ya) were one of those species I described to g3k, where they were one big population instead of tribes that were securely isolated over time. So maybe cheetahs are an example of Hardy-Weinberg forcing stasis. (Unlike humans & chimps, who both stayed in relatively small, isolated groups where gene drift could work.)