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The time has come to take seriously the fact that we humans are modified monkeys, not the favored Creation of a Benevolent God on the Sixth Day. In particular, we must recognize our biological past in trying to understand our interactions with others. We must think again especially about our so-called “ethical principles.” The question is not whether biology—specifically, our evolution—is connected with ethics, but how. As evolutionists, we see that no [ethical] justification of the traditional kind is possible. Morality, or more strictly our belief in morality, is merely an adaptation put in place to further our reproductive ends. Hence the basis of ethics does not lie in God’s will.... In an important sense, ethics as we understand it is an illusion fobbed off on us by our genes to get us to cooperate. It is without external grounding. Like Macbeth’s dagger, it serves a powerful purpose without existing in substance.
Ethics is illusory inasmuch as it persuades us that it has an objective reference. This is the crux of the biological position. Once it is grasped, everything falls into place.
-Michael Ruse and E. O. Wilson, “The Evolution of Ethics,” in Religion and the Natural Sciences: The Range of Engagement, ed. J. E. Hutchingson (Orlando, Fl.: Harcourt and Brace, 1991)

So you disagree with the scientific finding that we share 98% of our genes with chimpanzees?

Although the number and meaning of this finding can vary depending on the source, the ‘scientific’ philosophical implications remain.

With that in mind, consider the following representative statements made by leading sociobiologists. Richard Dawkins, easily the best-known spokesman for this movement, writes that ‘we are . . . robot-vehicles blindly programmed to preserve the selfish molecules known as genes',[1] and again that we are ‘manipulated to ensure the survival of [our] genes’.[2] The same writer also says that ‘the fundamental truth [is] that an organism is a tool of DNA’.[3] (That is, of the DNA molecules which are the organism’s genes.) Again, Dawkins says that living organisms exist for the benefit of DNA’.[4] Similarly, E. O. Wilson, an equal or higher sociobiological authority, says that ‘the individual organism is only the vehicle [of genes], part of an elaborate device to preserve and spread them…The organism is only DNA’s way of making more DNA’.[5]
Royal Institute of Philosophy

Human/chimp DNA similarity continues to decrease: counting indels

by Chase W. Nelson
Summary

It is conventionally held that humans and chimps differ only very slightly in their DNA. However, new evidence suggests that the difference might be much more drastic. Mutations resulting in DNA insertions and deletions cause much of the genetic difference between the two species, but are typically not included in estimates of diversity. Moreover, areas of significant similarity are often affected by selective constraints. An increasing number of functions are also being discovered for so-called ‘junk DNA’, suggesting similarity in such DNA is not necessarily due to common descent. Additional research should aid the understanding of such important data in the debate over origins.

Creationists have long maintained that the similarity between human and chimp DNA is not all that it is touted to be. A new study in the Proceedings of the National Academy of Sciences could help confirm this.

It is widely held that ‘The common chimpanzee (Pan troglodytes) is our closest relative. Its genome sequence is about 98.8% identical to our own, and we shared a common ancestor some six million years ago.’1 The assumption that humans diverged from chimps roughly this long ago also forms the basis of the mitochondrial clock,2 which ‘continues to be widely used to “time” human evolution and population movements, both ancient and modern.’3 In the popular-level book Genome, Matt Ridley states that:

‘Apart from the fusion of chromosome 2, visible differences between chimp and human chromosomes are few and tiny. In thirteen chromosomes no visible differences of any kind exist. If you select at random any “paragraph” in the chimp genome and compare it with the comparable “paragraph” in the human genome, you will find very few “letters” are different: on average, less than two in every hundred. We are, to a ninety-eight per cent approximation, chimpanzees, and they are, with ninety-eight per cent confidence limits, human beings. If that does not dent your self-esteem, consider that chimpanzees are only ninety-seven per cent gorillas; and humans are also ninety-seven per cent gorillas. In other words we are more chimpanzee-like than gorillas are.’4

One creationist response to such arguments regarding human/chimp DNA similarity has been that ‘Chimp DNA has not been anywhere near fully sequenced so that a proper comparison can be made’,5 and that this evidence is just as easily explained (and predicted, for that matter) by the concept of a common designer:

‘Since DNA codes for structures and biochemical molecules, we should expect the most similar creatures to have the most similar DNA. Apes and humans are both mammals, with similar shapes, so both have similar DNA. We should expect humans to have more DNA similarities with another mammal like a pig than with a reptile like a rattlesnake. And this is so. Humans are very different from yeast but they have some biochemistry in common, so we should expect human DNA to differ more from yeast DNA than from ape DNA.’6

In a recent article,7 David A. DeWitt cited a study which found that the two species are only 95% identical when insertions and deletions are considered,8 showing that the estimate of divergence depends mainly on what type of DNA is being compared. A number of differences between humans and chimps were named that are difficult to quantify in an estimate of sequence divergence (that is, the differences in bases between the human and chimp genomes), including shorter telomeres in humans, a 10% larger chimp genome, and great differences in chromosomes 4, 9, 12 and the Y chromosome, for example. Indeed, DNA similarity estimates ‘do not adequately represent fine changes in genome organization.’9
Considering DNA gaps

Previous estimates of sequence divergence have focused exclusively on base substitutions in DNA—that is, one base (or one DNA ‘letter’—A, T, C or G) being replaced with another. The new calculation, resulting in much less sequence similarity, also includes insertions and deletions, or indels, (occurring when a base is added or removed, often resulting in what is known as a frameshift mutation), in addition to base substitutions. The author of the study, Roy J. Britten, stated:

‘It appears appropriate to me to consider the full length of the gaps in estimating the interspecies divergence. These stretches of DNA are actually absent from one and present in the other genome. In the past, indels have often simply been counted regardless of length and added to the base substitution count, because that is convenient for phylogenetics.’8

His findings lend support to the idea that much of the failure of DNA to hybridize between chimps and humans is the result of missing DNA due to indel events. Britten then became involved in a follow-up paper in which these initial results were confirmed; in fact, it was found that ‘the 5% human-chimp difference already published is likely to be an underestimate, possibly by more than a factor of 2.’10
Various types of mutations

Various types of mutations. Much of the difference between human and chimp DNA can be attributed to insertions and deletions (indels).

Now, Anzai et al. have published a new report in the Proceedings of the National Academy of Sciences that confirms this statement. In the study, nearly one-half of the MHC (major histocompatibility complex) region was sequenced, ‘which to date represents the longest continuous sequence within this species [chimps], our closest evolutionary relative’, and has been described as a ‘rapidly evolving’ part of the genome.9 Although it has been held that human/chimp similarity in the MHC is ‘so great that the alleles must have originated before the supposed chimp/human evolutionary divergence’,11 the sequence results actually dropped the DNA similarity estimate down to 86.7%!12 Indeed, the actual difference between the two species (when counting indels) is greater than 5% by well more than a factor of two. Not only this, but ‘evolutionists now recognize that complex MHC genetic motifs can arise independently’ in primates—that is, at least some similarities that do exist are not attributable to common descent.13

The human genome contains two MHC Class I genes, the MICA and MICB, yet chimpanzees contain only one gene at this location, the Patr-MIC. According to evolutionary speculation, a 95-kb deletion occurred between the two human genes, forming the hybrid chimpanzee gene ~33–44 million years ago, by far predating the commonly held divergence date between the two species of 6 million years. Because the two ends of the chimpanzee gene seem to match up with the beginning of the human MICA and end of the human MICB genes, it may seem reasonable that common ancestry is feasible. However, even some humans contain a single gene at this location (called the HLA-B*4801 allele) very similar to the one found in chimps. The study notes that it ‘is quite intriguing that an equal-sized deletion involving this very same region and genes (MICA/B) has happened at distinct points in time in several different primate species’.12 Yet it is also claimed that other such similar changes in DNA structure cannot be attributed to convergence, but must be due to common ancestry! Clearly, similar ‘mistakes’ can arise independently in separate species (as expanded upon by Woodmorappe13). The hypothesis that a Designer would create the same structures for the same functions seems to explain the data much more easily. As noted by Woodmorappe,11 strong selective pressures must have existed in order to prevent the MHC similarities between primates from being scrambled over supposed millions of years, further weakening the evolutionary scenario.

http://www.answersingenesis.org/tj/v18/i2/similarity.asp