Evolutionist Francisco Ayala writes, “Molecular biology provides the most detailed and convincing evidence available for biological evolution.”[1] Darwinists often point out that humans share 99 percent of the same genetic makeup with chimpanzees. From this, they conclude that humans and chimps must be close relatives on the evolutionary tree.
Junk DNA is similar between humans and chimps.
Ancient Repetitive Elements (or ARE’s) are repetitive codes on the human genome that serve no functional purpose. Francis Collins explains that human pseudogene caspase-12 is functionless, and yet, our primate ancestors passed this useless code onto us through common ancestry.
Since Collins argued this, scientific findings have disregarded this. In 2012, 400 international scientists of the Encyclopedia of DNA Elements (ENCODE) reported that 80% of the human genome is now found to be functional—far from “junk” DNA.[2] Biologist James Shapiro writes, “One day, we will think of what used to be called ‘junk DNA’ as a critical component of truly ‘expert’ cellular control regimes.”[3] Biologist Richard Sternberg writes, “The selfish DNA narrative and allied frameworks must join the other ‘icons’ of neo-Darwinian evolutionary theory that, despite their variance with empirical evidence, nevertheless persist in the literature.”[4] In fact, 28 percent of people in sub-Saharan Africa have a functioning copy of the caspase-12 gene, as do lower percentages in some other human populations.[5] Francis Collins ignores the obvious explanation that caspase-12 was originally designed to be functional in humans but was rendered nonfunctional by a mutation in most human populations in the very recent past.[6] Two leading biologists write that “pseudogenes that have been suitably investigated often exhibit functional roles.”[7]
Humans share 99% of their DNA with chimps.
While this evidence is certainly strong, it is not necessarily conclusive or overwhelmingly in favor of evolution. In fact, a number of counterarguments can be made:
First, our common genetic makeup might be the result of a common Designer. When God went to create humans, he probably used a preexisting design plan to do it. Consider this argument from evolutionist Tim Berra in his book Evolution and the Myth of Creationism:
If you compare a 1953 and a 1954 Corvette, side by side, then a 1954 and a 1955 model, and so on, the descent with modification is overwhelmingly obvious… the evidence is so solid and comprehensive that it cannot be denied by reasonable people.[8]
Ironically, Berra’s words have backfired enormously. He failed to notice that the similarity between the successive Corvettes was not because of common descent—but because of common design! Evolutionists and ID advocates commonly refer to this as “Berra’s Blunder.” Moreover, we shouldn’t expect God to make us radically different from all other forms of life. After all, we all share a similar biosphere, and this might necessitate similar genes and to produce similar function. Without similar genes, a food chain would most likely be impossible.
Second, genetic similarity is also shared with other species. While humans share genetic makeup with chimps, we also share 35% similarity with daffodils.[9] Moreover, humans share 80% genetic similarity with mice.[10]
Third, common defects do not prove common ancestry. For instance, humans need Vitamin C, or they get scurvy. Most other mammals can produce Vitamin C on their own. However, humans have a defect in the last enzyme in the series that is shared by chimps and gorillas. This is a molecular mistake or a shared error on our genome. But, because of our environment, we ate enough fresh fruit, so that it didn’t affect our survival. So, we carried along this error. This appears to be good evidence for common ancestry between chimps, humans, and gorillas.
However, guinea pigs also have problems with scurvy, and primates like humans also share many of the same genetic errors. Moreover, humans don’t come from the same phylogenetic tree. Therefore, common mistakes on the genome do not always call for common descent.
Fourth, recent studies have challenged the standard 99% similarity. According to one recent study, humans only share 86% of the same genetic code with chimps.[11] Therefore, this similarity might not be as shocking as some make it out to be.
Fifth, physical similarities do not prove common ancestry. Wells writes, “The structure of an octopus eye is remarkably similar to the structure of a human eye, yet biologists do not think that the common ancestor of octopuses and humans possessed such an eye.”[12] In order to say that features are homologous (inherited from a common ancestor), we need to believe that they are from a common ancestor. For instance, even though a human eye and an octopus eye are similar, they are not homologous, because they have a separate common ancestor. However, homology is the very thing that supposedly proves common ancestry. Therefore, this evidence is guilty of circular reasoning.
Some experts in the field of biochemistry have grown skeptical of being able to create a traditional “tree of life” at all. Biochemist W. Ford Doolittle (PhD from Stanford and member of the U.S. National Academy of Sciences) writes, “Molecular phylogenists will have failed to find the ‘true tree,’ not because their methods are inadequate or because they have chosen the wrong genes, but because the history of life cannot properly be represented as a tree.”[13] New Scientist put it this way: “For a long time the holy grail was to build a tree of life… But today the project lies in tatters, torn to pieces by an onslaught of negative evidence.”[14]
[1] Ayala, Francisco José. Darwin and Intelligent Design. Minneapolis: Fortress, 2006. 37.
[2] The ENCODE Project Consortium “An Integrated Encyclopedia of DNA Elements in the Human Genome.” Nature. Volume 489. September 2012. 57. See article here.
[3] Richard Sternberg and James A. Shapiro, “How Repeated Retroelements Format Genome Function,” Cytogenetic and Genome Research 110 (2005): 108–16. Cited in House, H. Wayne. Intelligent Design 101: Leading Experts Explain the Key Issues. Grand Rapids, MI: Kregel Publications, 2008. 226.
[4] Richard Sternberg, “On the Roles of Repetitive DNA Elements in the Context of a Unified Genomic–Epigenetic System,” Annals of the New York Academy of Sciences 981 (2002): 154–88. Cited in House, H. Wayne. Intelligent Design 101: Leading Experts Explain the Key Issues. Grand Rapids, MI: Kregel Publications, 2008. 225.
[5] House, H. Wayne. Intelligent Design 101: Leading Experts Explain the Key Issues. Grand Rapids, MI: Kregel Publications, 2008. 227.
[6] House, H. Wayne. Intelligent Design 101: Leading Experts Explain the Key Issues. Grand Rapids, MI: Kregel Publications, 2008. 227.
[7] Evgeniy S. Balakirev and Francisco J. Ayla, “Pseudogenes, Are They ‘Junk’ or Functional DNA?” Annual Review of Genetics, 37 (2003), 123-51. Cited in Gauger, Ann, Douglas Axe, and Casey Luskin. Science and Human Origins. Seattle, WA: Discovery Institute, 2012. 91.
[8] Berra, Tim. Evolution and the Myth of Creationism. Stanford University Press. 1990. 177-199.
[9] Rana, Fazale, and Hugh Ross. Who Was Adam?: A Creation Model Approach to the Origin of Man. Colorado Springs, CO: NavPress, 2005. 220.
[10] Ross and Rana write, “Comparison of the mouse genome (reported in December of 2002) with the human genome supports Mark’s point. Of the 30,000 genes found in each of the human and mouse genomes, around 99 percent are the same. Only 300 genes are unique either to mice or to humans. Gene-to-gene DNA comparisons for humans and mice reveal roughly an 80 percent sequence similarity. Are humans 80 percent similar to mice? Are mice 80 percent similar to humans?” Rana, Fazale, and Hugh Ross. Who Was Adam?: A Creation Model Approach to the Origin of Man. Colorado Springs, CO: NavPress, 2005. 220.
[11] Tatsuya Anzai et al., “Comparative Sequencing of Human and Chimpanzee MHC Class 1 Regions Unveils Insertions/Deletions as the Major Path to Genome Divergence,” The Proceedings of the National Academy of Sciences, USA 100, no. 13 (June 24, 2003): 7708–13. Cited in Rana, Fazale, and Hugh Ross. Who Was Adam?: A Creation Model Approach to the Origin of Man. Colorado Springs, CO: NavPress, 2005. 214.
[12] Wells, Jonathan. Icons of Evolution: Science or Myth: Why Much of What We Teach about Evolution Is Wrong. Washington, DC: Regnery Pub., 2000. 62.
[13] W. Ford Doolittle, “Phylogenetic Classification and the Universal Tree,” Science, 284:2124-2128 (June 25, 1999). Cited in Luskin, Casey. More than Myth: Seeking the Full Truth about Genesis, Creation, and Evolution. Chartwell Press, 2014. 32.
[14] Partly quoting Eric Bapteste, in Lawton, “Why Darwin was Wrong about the Tree of Life.” New Scientist. January, 2009. Cited in Luskin, Casey. More than Myth: Seeking the Full Truth about Genesis, Creation, and Evolution. Chartwell Press, 2014. 32.