Increasing Homozygosity Affirms the Adam and Eve Hypothesis

Recognizing the increase of entropy and the slow march toward heat death had implications for the beginning of the universe as a space-time singularity, Roger Penrose in the 1970s posited the need for a state of low entropy in the classic Big Bang model.[1] Similarity, since the 1970s both neo-Darwinian and theistic-design theorists have recognized the problem of increasing homonymity and offered competing solutions for both the beginning and early conditions of human life. The former argues that the problem of increasing homonymity is resolved if humans evolved from an initial population base of 10,000. New Testament scholar Scot McKnight and biologist Dennis R. Venema argue in their book, Adam and the Genome, that evolution precludes any possibility of an Adam and Eve bottleneck and that humans must have “descend from a population that has never dipped below about 10,000 individuals”[2] Despite this effort to present the genetic evidence as an incontrovertible fact, some mainstream biologists have observed the flaws in Venema’s interpretation of the research[3] and conclude that the Adam and Eve bottleneck is a viable theory worth further examination.[4] In May 2018, evolutionary biologists Stoeckle and Thacker conclude that humans evolved somewhere between 100,000 and 200,000 years ago, but the data cannot be used to eliminate the argument for “the extreme bottleneck of a founding pair” and absolute assertions that the evidence demands belief in a stable population base of 10,000 which endured over ten millennia are “mere rhetoric.”[5] Venema himself has since the publication of his book conceded in online discussions that his research does not actually preclude the possibility of an original pair as the source for all humankind. [6]

Whereas the ND theorist is forced to account for genetic diversity and increasing homozygosity in humans by assuming a large population base, proponents of theistic-design argue that the best explanation of the evidence is that a single-pair were created with maximum heterozygosity (a state of low homozygosity). In this scenario, a single Adam and Eve pair contained all the genetic information necessary to allow their progeny to adapt to the diverse environmental conditions they encountered through migration. In the 1970s, the Adam and Eve hypothesis relied on strong circumstantial evidence,[7] but recent studies into the human genome have provided direct evidence from the statistical behavior of a large number of biological systems to substantiate the hypothesis.

Nathanial Jeanson offers a testable and falsifiable model which accounts for existing biological data through a population base of two humans. Recognizing the increase in homozygosity and the slow march toward extinction, Jeanson in 2017 posited the need for a low homozygosity beginning of humanity—or maximum heterozygosity. In Jeanson’s book, Replacing Darwin, he argues that the ND theorists who postulate life began with a single ancestor which became more heterozygous through genetic mutation (resulting in all the diverse species observed today) is impossible given the current DNA evidence. Instead, Jeanson argues, life evolved from the different created “kinds” (genus or family) uniquely created by God with genetic diversity (maximum heterozygosity) that becomes less genetically diverse (increasing homozygosity) as they adapts to new environmental changes.[8]  God created each kind with a vast genetic diversity such that when each allele is passed from the two parents, the progeny takes on the qualities necessary to survive in each unique environment without moving outside its own kind. Therefore, just as the physics of entropy leads to the probability that the universe began with a singular act of creation, so too the genetics of homozygosity leads to the conclusion that human life could not have evolved over billions of years of naturalisticevolution from molecule-to-man but is the result of a singular act of Divine creation.[9]

Where the Primary Axiom assumes mutations are the creative force generating genetic diversity by randomly evolving new information, the growing body of evidence by researchers such as Meyer, Axe, and Jeanson suggests that aging itself— as observed in chromosomal mutation leading to resistance to antibiotic resistance to bacteria —is due to the accumulation of near-neutral or deleterious cellular mutations. Therefore, the modern era of genetic information undermines the axiomatic assumptions of evolution and better explains the evidence of genetic novelty that is fundamental to the existence of animal life.[10]

In chapter 10 of his book, Replacing Darwin, Jeanson suggests that the linear correlation between the number of species in a family and the number of their unique mtDNA, when considered relative to the midpoint root in the family tree, helps determine pattern of speciation among living species. In the Bovine family, as one example, scientists observe a hierarchical pattern. Given that mtDNA functions like a clock, and branch points represent speciation events, it is possible to extrapolate a line of regression. This pattern of speciation was present in other tested families and allows for generalization into predictable equations represented in an increasing line of slope. Jeanson anticipates that as more mtDNA data is made available, the slope of the line will increase. These tests were done on species which both the theist and ND naturalist agree share common ancestry and whose differences in mtDNA are a result of mutation. Jeanson concludes that independent of an absolute time scale, the rate of speciation within a family is constant over time whereas the number of species is not constant. This information leads him to the conclusion that speciation closer to the root occurs more frequently but as time moves on there are more organisms participating in reproduction so the odds of any one line producing a new species decreases. That is, with each new generation, organisms became more homozygous and thus decreased in their rate of speciation. This data fits with the hypothesis that early organisms were created with high heterozygosity which through wholly natural processes produced more species.[11]

The power of Jeanson’s model is that it both accounts for the slow march toward extinction and provides a sound scientific mechanism though which a founding pair—Adam and Eve—could propagate the diversity found within humankind. Jeanson’s’ model of preexisting genetic diversity defines the three elements of the speciation process: (1) formation of genetic distinctiveness, (2) isolation of the distinct individuals through multiple mechanism (e.g. natural selection, migration, genetic drift, etc…), and (3) growth of a new population. Each of these can occur in this order, or out of order. In this model, humans moved from maximally heterozygous ancestors to more homozygous modern humans. Since humans started with millions of heterozygous DNA sites, genetic distinctness could happen within a single generation. Both ND evolutionists and Jeanson agree that step three is rapid. However, for ND evolutionists the first two steps of the speciation involve long periods of time. For the ND evolutionist, diversity was not created from the start, but accumulated over long periods of time through genetic mutation. In contrast, Jeanson’s model suggests that both steps one and two are rapid because the preexisting heterozygosity (distinct from near neutral variation) at the origin of human kind creates a high potential for speciation.[12]

While evidence from other research mitigates any commitment to an absolute time scale for the original human pair,[13] Jeanson’s work analyzing human mtDNA mutation rates does provide a falsifiable scientific model for evaluating future genomic research against the biblical account of human origins. The best explanation for the existence of humankind that incorporates well the existing scientific data is that God created Adam and Eve as the root of all humanity in a state of maximum heterozygosity with an ever-increasing homozygosity. This biological model is compatible with the interpretation of Scripture that presents a historical Adam and Eve as the fountainhead for all humanity.^[14] The Adam and Eve’ bottleneck as a seminal event in human history is consistent with modern genetic research leaving only the unanswered question of timescale.

Summary and Conclusion

In response to Poincaré question, the argument presented in this paper supports the high probability of the Adam and Eve hypotheses. The observable condition of increasing biological homozygosity coupled with the model of speciation from a state of maximum heterozygosity affirms the compatibility of the orthodox Christian view of human creation with the best scientific data. Darwin’s theory of natural selection is fatally dependent on an infinite variability over long periods of time producing biological diversity. Observations from sympathetic scientist like Schrodinger, have not been able to rescue the Primary Axiom from its own philosophical assumptions. With modern scientific information of human DNA, it is clear that the conditions necessary for natural selection do not exist and consequently Neo-Darwinian theory fails.

The data from the latest scientific studies outlined in this paper makes a strong case that increasing homozygosity, like entropy, substantiates the Fine-Tuning argument. This argument is supported on two fronts. First, just as the thermodynamic increase of entropy will eventually lead to the heat death of the universe, the biological increase in homozygosity cannot be saved by the neo-Darwinian mechanism of mutation and will eventually lead to the extinction of life. Second, just as the physics of entropy leads to the conclusion that the universe began with a singular act of creation, so too the genetics of homozygosity lead to the conclusion that human life did not result from millions of years of naturalistic evolution from molecule-to-man but is the result of a singular act of Divine creation. Although there is no definitive evidence affirming a specific timescale, the creation of an original pair in a state of low homozygosity (or maximum heterozygosity) is far more probable given the existing evidence then the theory of human life resulting from random genetic mutation within a small population base.

The strength of this argument for biological fine-tuning is that it avoids the God of the Gaps fallacy because while it allows for God to establish the initial human condition of maximum heterozygosity, it does not require supernatural intervention to sustain the natural order or to explain speciation. The argument does not require God’s miraculous intervention to create biological diversity because it is demonstrably built into to human genetic code through maximum heterozygosity from the first creation. This argument answers well the charge by some ND theorists like Gert Korthof that intelligent design is an all-or-nothing proposition that rejects scientific observations of species diversification.[15] Ultimately, neither the ND nor the theistic-design models can be tested for their initial assumptions, but both are testable in their predictive assertions concerning observations of increasing homozygosity.