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Thursday, June 13, 2019

Human or Chimp?

While Locke’s and Frazer’s team was unwilling to commit to any new estimate of the similarity between chimps and humans, Britten was not. In fact, he titled his article in the October 15, 2002 Proceedings of the National Academy of Sciences, “Divergence between Samples of Chimpanzee and HumanDNA Sequences is 5%” (Britten, 99:13633-13635). In the abstract accompanying the article, he wrote: “The conclusion is that the old saw that we share 98.5% of our DNA sequence with chimpanzee is probably in error. For this sample, a better estimate would be that 95% of the base pairs are exactly shared between chimpanzee and humanDNA”(99:13633, emp. added).

 The news service at NewScientist.com reported the event as follows: It has long been held that we share 98.5 per cent of our genetic material with our closest relatives. That now appears to be wrong. In fact, we share less than 95 per cent of our genetic material, a three-fold increase in the variation between us and chimps.

The new value came to light when Roy Britten of the California Institute of Technology became suspicious about the 98.5 per cent figure. Ironically, that number was originally derived from a technique that Britten himself developed decades ago at Caltech with colleague Dave Kohne. By measuring the temperature at which matching DNA of two species comes apart, you can work out how different they are. But the technique only picks up a particular type of variation, called a single base substitution.

 These occur whenever a single “letter” differs in corresponding strands of DNA from the two species. But there are two other major types of variation that the previous analyses ignored. “Insertions” occur whenever a whole section of DNA appears in one species but not in the corresponding strand of the other.

 Likewise, “deletions” mean that a piece of DNA is missing from one species. Together, they are termed “indels,” and Britten seized his chance to evaluate the true variation between the two species when stretches of chimp DNA were recently published on the internet by teams from the Baylor College of Medicine in Houston, Texas, and from the University of Oklahoma.

When Britten compared five stretches of chimp DNA with the corresponding pieces of human DNA, he found that single base substitutions accounted for a difference of 1.4 per cent, very close to the expected figure. But he also found that the DNA of both species was littered with indels. His comparisons revealed that they add around another 4.0 per cent to the genetic differences (see Coghlan, 2002, emp. added). It seems that, as time passes and scientific studies increase, humans appear to be less like chimps after all.

 In a separate study, Barbulescu and colleagues also uncovered another major difference in the genomes of primates and humans. In their article “A HERV-K Provirus in Chimpanzees, Bonobos, and Gorillas, but not Humans,” the authors wrote: “These observations provide very strong evidence that, for some fraction of the genome, chimpanzees, bonobos, and gorillas are more closely related to each other than they are to humans”(2001, 11:779, emp. added).

 The data from these results go squarely against what evolutionists have contended for decades—that chimpanzees are closer genetically to humans than they are to gorillas. Another study using interspecies representational difference analysis(RDA)between humans and gorillas revealed gorilla-specific DNAsequences (Toder, et al., 2001)—that is, gorillas possess sequences ofDNAthat are not found in humans. The authors of this study suggested that sequences found in gorillas but not humans “could represent either ancient sequences that got lost in other species, such as human and orang-utan, or, more likely, recent sequences which evolved or originated specifically in the gorilla genome” (9:431).

 The differences between chimpanzees and humans are not limited to genomic variances. In 1998, a structural difference between the cell surfaces of humans and apes was detected. After studying tissues and blood samples from the great apes, and sixty humans from various ethnic groups, Muchmore and colleagues discovered that human cells are missing a particular form of sialic acid (a type of sugar) found in all other mammals (1998, 107[2]:187). This sialic acid molecule is found on the surface of every cell in the body, and is thought to carry out multiple cellular tasks.

 This seemingly “minuscule” difference can have far-reaching effects, and might explain why surgeons were unable to transplant chimp organs into humans in the 1960s. With this in mind, we never should declare, with a simple wave of the hand, “chimps are almost identical to us” simply because of a large genetic overlap. Homology (i.e., similarity) does not prove common ancestry. The entire genome of the tiny nematode(Caenorhabditis elegans)also has been sequenced as a tangential study from the Human Genome Project. Of the 5,000 best-known human genes, 75% have matches in the worm (see “A Tiny Worm Challenges Evolution”).

 Does this mean that we are 75% identical to a nematode? Just because living creatures share some genes with humans does not mean there is a linear ancestry. Biologist John Randall admitted this when he wrote: The older textbooks on evolution make much of the idea of homology, pointing out the obvious resemblances between the skeletons of the limbs of different animals. Thus the “pentadactyl” [five bone—BH/ BT]limb pattern is found in the arm of a man, the wing of a bird, and flipper of a whale, and this is held to indicate their common origin.

Now if these various structures were transmitted by the same gene couples, varied from time to time by mutations and acted upon by environmental selection, the theory would make good sense. Unfortunately this is not the case. Homologous organs are now known to be produced by totally different gene complexes in the different species. The concept of homology in terms of similar genes handed on from a common ancestor has broken down… (as quoted in Fix, 1984, p. 189).

Yet textbooks and teachers still proclaim that humans and chimps are 98% genetically identical. The evidence clearly demonstrates vast molecular differences—differences that can be attributed to the fact that humans, unlike animals, were created in the image and likeness of God(Genesis 1:26-27; see Lyons and Thompson, 2002a, 2002b). Elaine Morgan commented on this difference when she observed: Considering the very close genetic relationship that has been established by comparison of biochemical properties of blood proteins, protein structure and DNAand immunological responses, the differences between a man and a chimpanzee are more astonishing than the resemblances.

They include structural differences in the skeleton, the muscles, the skin, and the brain; differences in posture associated with a unique method of locomotion; differences in social organization; and finally the acquisition of speech and toolusing, together with the dramatic increase in intellectual ability which has led scientists to name their own species Homo sapiens sapiens—wise wise man.

 During the period when these remarkable evolutionary changes were taking place, other closely related ape-like species changed only very slowly, and with far less remarkable results. It is hard to resist the conclusion that something must have happened to the ancestors of Homo sapiens which did not happen to the ancestors of gorillas and chimpanzees (1989, pp. 1718, emp. added). That “something” actually is “Someone”—the Creator.

The Truth About Human Origins

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