87  The human and chimpanzee genomes
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The difference between the genomes of humans and chimpanzees has been claimed in the past to be 1.5 to 2%. Molecular biologist Roy J. Britten has determined that, when the insertions and deletions are included in the calculation, the difference is nearly 5%. This means that at least seventy-five million “correct” mutations would have been necessary to make a modern human and a chimpanzee from a common ancestor. Even if one advantageous mutation per year had occurred in these populations, a total of seventy-five million years would have been necessary, whereas the evolution of humanity is supposed to have taken only two million years. According to calculations by genetic pioneer J.B.S. Haldane, a realistic estimation of the time that would have been required for this process is at least 2.5 billion years.


 
The scientific consensus today is that the difference between the genome of humans and chimpanzees amounts to 1.5 to 2%, purportedly supporting a relationship between apes and humans. However, Britten determined that the difference is nearly 5% when the insertions and deletions are included in the calculation (1) (2). It is also possible that even a greater difference may be discovered, since only a small fraction of the genome has been compared to date. Of the total of three billion base pairs in the human genome, only about one million had been compared by the year 2008.


Differences between the human and chimpanzee genomes:

1) Humans have twenty-three chromosome pairs, chimpanzees twenty-four.

2) There are special sequences at the end of each chromosome called telomeres. Apes have about twenty-three kilo basepairs, humans only ten.

3) Whereas eighteen chromosome pairs are practically identical, the genes and markings are in a different order in chromosomes four, nine, and twelve.

4) The Y chromosome has a different size and many markings that do not match.

5) Chromosome twenty-one contains large regions that are completely different.

6) The chimpanzee genome is 11.5% larger than the human genome.


As we said above, the chimpanzee genome is 11.5% larger than the human genome (3). How could there be a difference of only one percent if the genome of the chimp contains 11.5% more? This is not possible. The 11.5% are simply ignored. In fact we do not yet know the difference between the human genome and the genome of the chimp (4).

A book we recommend on this subject is Genetic Entropy & the Mystery of the Genome, published by geneticist John C. Sanford in 2005. Sanford shows that the genome loses more and more information over time until the species goes extinct.


Haldane’s dilemma:
 
When a useful mutation occurs in a population, as many copies of it as possible must be distributed so that evolution can continue. In other words, the individuals that do not yet contain this mutation must be replaced. The rate at which this process can take place, however, is limited. One of the main limiting factors is the propagation rate of the given species. For a hominid species with a generation interval of twenty years and a low reproductive rate per individual, mutations spread very slowly through the population (5).

John B.S. Haldane (1892-1964) is one of the three founders of the modern science of population genetics. He assumed for a rough calculation a population of 100,000 ancestors in which one male and one female underwent a mutation at the same time that was so beneficial that they outlived all the others, which is also highly unlikely. All the rest (the other 99,998) of the population died out and the surviving pair multiplied, eventually replenishing the entire population. This process would have to be repeated over the course of ten million years in each generation (i.e., every twenty years) to introduce 500,000 (10,000,000/20) advantageous and perfectly-adapted mutations into the population. These 500,000 mutations would then amount to only 0.02% of the necessary 5%. If more realistic rates of fitness/selection and population renewal are assumed, even 2.5 billion years will not be nearly enough.

Haldane’s dilemma was still a topic of discussion in scientific journals back in 1960, but the subject has been ignored since that time (6). This may be because mathematical modelling of such processes in population genetics is extremely complex. Research in the field today concentrates primarily on determining the number of advantageous mutations that can be determined to have actually occurred. Important elements that would enable us to continue with such calculations are still missing.

In 1992, the well-known evolutionary geneticist George C. Williams remarked, “The time has come for renewed discussion and experimental attack on Haldane’s dilemma” (7). The appeal apparently produced no echo among his colleagues. Walter ReMine published a large study in 1993 in which he investigated the matter in detail (8). He continued work in this field, refined his arguments and addressed attempts by evolutionists who would like to obfuscate the matter. Unfortunately, no serious dispute of the matter has resulted to date. ReMine reminds us that Haldane’s dilemma has never been solved, but only hushed up, misrepresented and prematurely dismissed (9).



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References:

(1) Roy John Britten, Divergence between samples of chimpanzee and human DNA sequences is 5% counting indels, Proc. Nat. Acad. Sci., 99, USA, 2002, pages 13633–13635.
(2)
 David A. DeWitt, 98% Chimp/human DNA similarity? Not any more, Technical Journal 17/1, 2003, pages 8–10.
(3) CRSQ 45/4, (2009): pages 242-243.
(4) Chimpanzee Sequencing and Analysis, Consortium (CASC). 2005. Initial sequence of the chimpanzee genome and comparison with the human genome. Nature. 437:pages 69–87.
(5) John Burdon Sanderson Haldane, The cost of natural selection, Journal of Genetics 55, 1957, pages 511–524.
(6) Don Batten, Haldane’s Dilemma has not been solved, Technical Journal 19/1, 2005, pages 20–21.
(7) George Christopher Williams, Natural Selection: Domains, Levels and Challenges, Oxford University Press, NY, 1992, pages 143–144.
(8) Walter J. ReMine, The Biotic Message, St. Paul Science, St. Paul, MN, 1993.
(9) Walter J. ReMine, Cost theory and the cost of substitution - a clarification, Technical Journal 19/1, 2005, pages 113-125.

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