2 Views on Human Evolution: Evolutionary-Creation vs. Unique-Origin
Discussions surrounding Christianity and science have been fraught with taut rhetoric and polarizing polemics on both sides of the aisle. The new Dictionary of Christianity and Science aims to shape these conversations by offering a framework for better dialogue.
Perhaps in no other discussion do we need such a sure, sturdy referee than in the one surrounding human origin. Through the Dictionary‘s “Multiple-View Discussions” entry type, two able scientists lead the discussion: Darrel R. Falk and Ann Gauger.
Below, we’ve engaged one aspect of their lengthy, robust discussion: the genetic evidence for so-called common descent—the view that our species, Homo sapiens, descended from ape-like ancestors.
We trust it will give you a taste of this definitive reference, showcasing why Scot McKnight says “Every Christian studying science will want a copy within arm’s reach.”
The Evolutionary-Creation View on Human Evolution
Falk, professor of biology at Point Loma Nazarene University and Senior Advisor for Dialogue at BioLogos, acknowledges “Few matters are of greater concern to Christians than our own origin as a species” (228). He offers three evidence types that indicate “God created humankind through the process of common descent from earlier formed primates” (229): mutation rate, genetic “scars,” and synonymous coding. We’ll consider two.
First, human genetic information changes (mutates) slightly from one generation to the next, measured precisely as “an average of 70 base changes (out of 6 billion)” (229). Which means, the further back in time you go, the more genetic differences we have with our ancestors. Here’s the significance for us:
If common descent is true, then one can calculate how many changes (mutations) would have occurred in the 6 million years (60,000 centuries) since the common ancestral species of both chimpanzees and humans existed…that number of genetic differences is within twofold of the predicted number. (229)
Falk also explains that our genetic code contains synonyms: “Certain parts of our genetic code can be written in alternative ways that mean exactly the same thing to cells” (230).
He offers an example: You could say “Pick up that circular red object” or “Pick up that round red object” and they’d essentially mean the same thing. Synonymous coding conveys similar information. Falk explains:
There are millions of potential synonyms in the genome and differences in them are abundant when one compares the chimpanzee DNA sequence to that of the human. There are also many potential nonsynonymous changes, but these differences are much less frequent. This is what one would expect if there were a single ancestral species. (230)
Falk concludes, “Both genetic data and the fossil data have emerged with a great deal of force over the past two decades, and the two sets of data together are considered by almost everyone in the field of biology as exceedingly strong evidence for human evolution” (230).
The Unique-Origin View on Human Evolution
As Senior Research Scientist at Biologic Institute and a Senior Fellow at the Discovery Institute’s Center for Science and Culture, Gauger believes “the biological data dealing with our origins must…be critically examined and not taken automatically as leading to one conclusion” (235). Her essay largely analyzes this data, particularly the genetic aspects—two of which correspond with Falk’s points above.
Gauger also takes up the use of mutations. She suggests, “In small populations, like ours would have been, mutations are likely to be lost and have to recur many times before they actually stick” (236). Such mutations affect DNA binding sites, small stretches of DNA that regulate how much product neighboring genes make.
Based on recent studies using numerical simulations, one specific mutation necessary to make a new DNA binding site would take 1.5 million years; 84 million years for two DNA sites; the estimate divergence time from chimps to humans is 6 million years.
What about the reuse of so-called synonymous code, the assumption that such codons can be used interchangeable? Gauger recalls the argument: “When there is a choice among possible codons, chimp and human genomes almost always use the same codon. It is therefore argued that this is because the sequences share a common ancestor” (238). So, for example, lysine can be encoded as CUU, CUC, CUA, or CUG.
Yet “it has since been discovered that codons are used for multiple purposes—which codons are used changes the DNA sequence…” Gauger suggests such synonymous coding is functional: “they have to perform multiple jobs that are specific to one codon—none of the others will do” (238). She concludes, “The fact that both humans and chimps use the same codons may be due to this rather than ancestry” (238).
“Are we the product of common descent from an apelike ancestor, or are we unique, with a distinct origin? The answer to this question impacts how we see ourselves and the world around us, and how we integrate religion and science” (241).
Both Falk and Gauger believe discussions surrounding our origin and the nature of our being are essential discussions—ones that require a sure, sturdy guide.
Navigate such discussions with this guide, and see why Lee Strobel insists “This is an invaluable resource that belongs in every Christian’s Library.”