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Time Aping over Human-Chimp Genetic Similarities

The current issue of Time features a cover story preaching evolution to the skeptical public and editorializing that humans and chimps are related. Though the cover graphic (below) shows half-human, half-chimp iconography, University of North Carolina, Charlotte anthropologist Jonathan Marks warns us against “exhibit[ing] the same old fallacies: … humanizing apes and ape-ifying humans” (What It Means to be 98% Chimpanzee, pg. xv [2002]). The cover-graphic commits both fallacies:

Time Cover Graphic

The article also claims that it’s easy to see “how closely the great apes — gorillas, chimpanzees, bonobos and orangutans — resemble us,” but then observes in a contradictory fashion that “agriculture, language, art, music, technology and philosophy” are “achievements that make us profoundly different from chimpanzees.” Perhaps Michael Ruse was wise to ask “[w]here is the baboon Shakespeare or the chimpanzee Mozart?” (The Darwinian Paradigm, pg. 253 [1989]).

Common Descent, or Common Design?

The article predictably touts the 98-99% genetic similarity statistic between humans and chimps, assuming that the similarity demonstrates common ancestry. Can common ancestry explain shared functional genetic similarities between humans and chimps? Sure, of course. But so can common design: designers regularly re-use parts that work when making similar blueprints. The article ignores that shared functional similarities between two organisms do not rule out design in favor of descent.

Evolutionary Miracle Mutations

The article also discusses a “mutation” that could allow a loss in jaw-muscle strength, which evolutionary biologists hypothesize allowed the human braincase to grow larger. It’s a nice just-so story, but paleoanthropologist Bernard Wood explained why simply identifying these genetic differences does not provide a compelling evolutionary explanation where natural selection would preserve the mutations:

“The mutation would have reduced the Darwinian fitness of those individuals … It only would’ve become fixed if it coincided with mutations that reduced tooth size, jaw size and increased brain size. What are the chances of that?”

quoted in Joseph Verrengia, “Gene Mutation Said Linked to Evolution” Union Tribune, 03-24-04

The article also makes the unbelievable claim that two mutations could account for “the emergence of all aspects of human speech, from a baby’s first words to a Robin Williams monologue.” Are they joking? If human speech evolved via Darwinian means, it would require slowly evolving a suite of highly complex characteristics lacking in animals — a feat some experts think is impossible:

Chomsky and some of his fiercest opponents agree on one thing: that a uniquely human language instinct seems to be incompatible with the modern Darwinian theory of evolution, in which complex biological systems arise by the gradual accumulation over generations of random genetic mutations that enhance reproductive success. … Non-human communication systems are based on one of three designs [but] … human language has a very different design. The discrete combinatorial system called “grammar” makes human language infinite (there is no limit to the number of complex words or sentences in a language), digital (this infinity is achieved by rearranging discrete elements in particular orders and combinations, not by varying some signal along a continuum like the mercury in a thermometer), and compositional (each of the infinite combinations has a different meaning predictable from the meanings of its parts and the rules and principles arranging them).

Pinker, S., Chapter 11 of The Language Instinct (1994).

While Pinker believes that human language can be explained by Darwinism, human speech and language is exceedingly complex compared to animal language. Claiming it could evolve in two mutations is unbelievable.

Functional Non-Coding DNA: The Evolutionists’ New Best Friend?

Ironically, the article admits that stark differences between humans and chimps may stem from functional non-coding DNA, which regulates protein production. In an elegant analogy, Owen Lovejoy explains that the 98-99% similarity in coding-regions of DNA (“bricks”) may be irrelevant because it’s “like having the blueprints for two different brick houses. The bricks are the same, but the results are very different.”

Darwinists often cite similarities in non-coding DNA as evidence of chimp-human common ancestry. Yet the Time article explains that non-coding DNA has function–perhaps holding the functions responsible for the differences between humans and chimps:

Those molecular switches lie in the noncoding regions of the genome–once known dismissively as junk DNA but lately rechristened the dark matter of the genome. … “But it may be the dark matter that governs a lot of what we actually see.”

Though the article still asserts much of the genome is junk, Richard Sternberg and James A. Shapiro wrote recently that “one day, we will think of what used to be called ‘junk DNA’ as a critical component of truly ‘expert’ cellular control regimes” (“How Repeated Retroelements format genome function,” Cytogenetic and Genome Research 110:108 — 116 [2005]).

Evidence of function in non-coding DNA not only casts doubt upon whether the 98-99%-protein-coding-DNA-similarity statistic is relevant to assessing the degree of genetic similarity between humans and chimps, but it also shows that similarities in human and chimp non-coding DNA could be explained by common design.

Casey Luskin

Associate Director, Center for Science and Culture
Casey Luskin is a geologist and an attorney with graduate degrees in science and law, giving him expertise in both the scientific and legal dimensions of the debate over evolution. He earned his PhD in Geology from the University of Johannesburg, and BS and MS degrees in Earth Sciences from the University of California, San Diego, where he studied evolution extensively at both the graduate and undergraduate levels. His law degree is from the University of San Diego, where he focused his studies on First Amendment law, education law, and environmental law.