Evolution and the Sin in Eden
A New Christian Synthesis

Chapter 4: A Couple or a Population?

Among those who believe that the our human bodies descended from living animal origins, some are more comfortable with the idea that our race began with a population rather than with a single couple. Though the teaching office of the Catholic Church may not be definitively opposed to the population concept, the current teaching points to a couple and not to a population, at least until reasons to change become convincing. Pope Pius XII found this difficulty with the population theory:

It is not at all apparent how such a view (polygenism) can be reconciled with the data which the sources of revealed truth and the documents of the Church propose concerning original sin, namely, that it originates from a sin truly committed by one Adam, is transmitted to all through generation and is in each person, proper to him (cf. Rom 5:12-19); Encyclical Humani Generis, 1950; DS 3896; Dupuis 420).

Theologians feel challenged to explore ways in which polygenism can be reconciled with the doctrine of original sin when they see this explanation of Pope Pius XII. The words: "for it is not at all apparent ..." leave the door at least partially open for further study.

Theories Favoring a Population

An explanation designed to bridge the gap between supporters of polygenism vs. advocates of a single couple origin made by Z. Alszegy and M. Flick received considerable attention when first announced. They proposed that one single couple who had already achieved full use of reason was responsible for this sin. This couple formed part of a larger group who had not yet achieved full moral responsibility. These others are presented as being in a state of undeveloped childhood. According to the testimony of Holy Scripture the first man is to be viewed as a corporate person, whose decision becomes the fate of the group; and thus the actual sin of a single person could become the hereditary sin of the rest of the people. I am not aware that this theory has received widespread acceptance. Fr. Ferdinand Holboeck (p.149) rightly observes that this and similar theories do not exceed the value of inconclusive speculation.

If I understand the above theory correctly, it is not much of an improvement over the older explanation of Thomas, namely that the first couple sinned personally, and the rest of humanity inherited their sin. To me the explanation appears artificially contrived. It is apparently designed to meet the opinion of those who hold to the theory of human evolution from animal stock, and who believe that the science of genetics would demand a larger gene pool for the origin of Homo Sapiens than one single couple. There is no unanimity among scientists about this. Geneticist Jerome Lejeune, (see below) held quite the opposite opinion, namely that a genetic novelty spreads more easily from a single source than from a dissipated group.

An Isolated Gene Pool

We may speculate that our Adam and Eve ancestors were born into an existing population, but broke away from them and launched our race in isolation from the parent group. It is not at all inconceivable that a single pair of humans, or a small population, can become isolated from the rest of humanity in a hunter-gatherer kind of social situation. Only recently, for example, a small tribe of hunter-gatherers in the mountains of New Guinea, isolated into an area on the border of the Enga highlands and the Province of Madang, contacted our SVD missionaries to ask for help. Their group of only 302 persons feared that they would die out if they received no outside help. They had known practically nothing about the rest of the world before 1983 (SVD Arnoldus, January/February 1983, p.8). If this group was isolated from the rest of the inhabitants of New Guinea from as long as their memory goes back, we can reasonably suppose that an Adam and Eve could detach themselves from the rest of humanity terminally.

Nor is it inconceivable that populations living prior to our Homo Sapiens race became extinct. We know of Australopithecus hominids from 4 million year old fossils (see Lucy, 202) but they are no more today. Fossils of Homo Habilis, of Homo Erectus, and of Neanderthal tell us the story that they once existed, but are no more. We know also that many nations of the Homo Sapiens race once flourished in great numbers, but have now become extinct. Corrado Gini counted up a number of nations once demographically numerous which are now extinct:

Examples of the progressive decadence of primitive populations, apparently doomed to certain death, are very numerous. They are to be met with in all continents; in the northern regions of Asia, of Europe, and America, the Australian continent, and the Malayan and Oceanian archipelagoes, the islands of the coast of Indo-China, and the interior of the peninsula, a place in Palestine, central Africa, some of the Indian reservations of Canada and of the United States, the virgin forests of the Amazons, and in the extreme south of the American continent (Gini, p. 51).

Biological decay, believes Gini, is the principle cause of their death, but diseases, abuses, wars, violent social changes may be the final critical factor. During relatively modern times many of the Australian hunter-gatherers were decimated or wiped out by diseases contracted from white men for which they had not developed resistance. The same is true of American Indians of a hundred years ago, and of Amazonians today. It is also known that internecine wars sometimes wiped out competitive groups of hunter gatherers. Climatic conditions also played their role, and some believe that the Neanderthal people were wiped out when glaciers invaded their habitats, or when Homo Sapiens perhaps eliminated them.

Finally, it is not at all inconceivable that our Adam and Eve people would remain genetically isolated from other populations, either for geographic reasons, or because of social and linguistic barriers. Linguistic and cultural barriers can isolate genetic pools from each other as effectively as impassable mountain ranges, vast oceans, and impenetrable forests.

Population Theories and Genetics

The theory of human evolution from an animal origin is compatible with the above theoretical scenario. After the original pair had become genetically isolated from their parent gene pool, their own genetic endowment could give rise to the vast population of the world today with its evidently rich genetic endowments.

Geneticist Jerome Lejeune, for example, observed that if our race is a new species, then a single couple to start the species is more logical than a group of people or a population:

Indeed I am of the opinion that the whole chromosomal mechanics require that every species must have arisen in an extremely inbred and small population. The calculus from genetics shows that the optimal solution would be to start with a unique couple, carrier of the chromosomal novelty in the homozygous state (Lejeune, private correspondence, 19 February 1987, permission obtained).

Note that the eminent geneticist, now deceased, did not claim here that Homo Sapiens IS a new species. He observes only that IF ours is a new species, then the calculus from genetics would point to a couple rather than to a corporate population as its base of origin.

Genetic calculations also practically exclude the possibility that a Homo Sapiens race would begin spontaneously in several parts of the world. Rather, there can be only one source of our race, only one cross-over from the animal world into human society. That is, if a species-specific mutation from animal to human, or from one human species to another, occurred in Africa, for example, and another occurred in a genetically isolated population in Asia or elsewhere, the two new species would not be identical. They would not be capable of cross-fertilization to beget offspring. A concept that multiple lines evolved into a new species separately in genetically isolated situations, and that the species was the identical and single species of Homo Sapiens is, in all likelihood, not defensible by genetic calculus. Our Homo Sapiens race, therefore, if it is specifically different from Homo Habilis, Erectus, and Neanderthal, began at one place only, not in several and independent isolated gene pools.

Mitochondrial DNA Converges

Newsweek of January 11, 1988 described studies which point to a convergence of our family tree. The tree converges toward an African woman who lived about two hundred thousand years ago. The DNA examined in the research is not that which is inside the nucleus of human cells but outside of it in mitochondrion compartments. This is inherited only from the mother, not from the father, and is therefore useful for tracing family lines through the female ancestors. This mitochondrial DNA is not scrambled with that of the father, as is the case with the DNA which is within the nucleus of cells. This provides it with a marker by which changes can be traced in generations of women.

Minute changes in the mitochondrial DNA occur during the course of time, and these changes can be traced, step by step, back to the source of the novelty. The changes diverge in different directions among populations that are genetically isolated from each other.

The Berkeley group who did the study obtained mtDNA by collecting placentas of women in America with ancestors from Africa, Europe, the Middle East, and Asia, and from Aborigines in Australia and New Guinea. They found two main categories of the mtDNA, one found only in some babies of a certain population of recent African descent, and a second found in all others, including other Africans. They concluded that the former line is the oldest, that all the other lines branched off from it. The researchers assumed a steady rate of mutations and by this molecular calculus came upon the original woman. She lived in Africa, they say, some two hundred thousand years ago (a range between 140,000 and 290,000 years ago). That would locate the single and unique mother of our entire present human race in Africa.

Professor Lucotte of the Sorbonne, Paris, conducted studies on the DNA of the Y sex chromosome which is exclusively male. A similar branching pattern emerged. It converged on a male ancestor of our race who was also African (Campbell 447). But the results are admittedly tentative and highly controversial. If these findings are true they point to Africa as the locus of the origins of our contemporary race. These studies do not indicate by themselves, however, that a monogamous couple launched our race.

Be that as it may, we have an independent source of knowledge by which we know that our primal ancestors were monogamous. Christ testified in Matthew chapter nineteen that "in the beginning" the union of one husband and wife was arranged by God, and only later did divorce and re-marriage come into practice. This saying of Christ evidently describes fact not symbolism, for Christ made God's initial arrangement of monogamy to be the model on which He restored Christian marriage to the pristine condition. The possibility remains, of course, that there was an original population with numerous families all of which were monogamous. Christ's statement, by itself, does not exclude that possibility.

Theological Indications Favor a Couple

Do theologians have reasons to conclude that it was one single couple who began our present human race, and to exclude even a small genetically isolated population of monogamous couples? Luke traces the genealogy of Jesus back to an initial ancestor "Adam, son of God" (3:38). This single source has symbolic significance, it appears, for the Evangelist makes quite an issue about the ancestry of Christ. The beginning of the genealogical tree is Adam. If Adam was not this specified individual but an unknown and unnamed person within an initial general population then Luke's superb narrative would lose its punch line. Luke's genealogy has a rhythmic regression through seventy-six generations of ancestors. We know many of them from the Bible as colorful individuals. The line of royal ancestry crescendoes to a climax in Adam, son of God:

Jesus, when he began his ministry was about thirty years of age, being the son (as was thought) of Joseph, the son of Heli, the son of Matthat, the son of Levi, the son of Melchi... etc. etc.... the son of Mahalaleel, the son of Cainan, the son of Enos, the son of Seth, the son of Adam, the son of God (Lk 3:23-38).

It would be an anti-climax to read instead at the end: " the son of Seth, the son of an unidentified parent in an initial population." Luke's charming genealogy builds up an esteem for Christ in the reader, who already knows the Adam well from the pages of the Bible, the one who is Christ's human ancestor as well as our own. Luke marks us as relatives of the human Christ, who shares His ancestry with us. We would extinguish and lose one very significant detail of the heritage of our Faith, I believe, if we would replace our "Adam" of Bible with a "Conglomerate Population" of science. Even from a literary standpoint, a banal "conglomerate population" does not stand up to the exquisite climax of Luke's "Adam, the son of God." It would be an anti-climax, a departure from the elegant style of Luke and from his accustomed minute care about meaningful details. As for myself, I opt for my family tree to start with Adam, and would hate to change him for a nameless parent belonging to an initial population.

Two significant theological considerations converge, I believe: Luke states that the ancestor was Adam. Matthew states that he was monogamous. Put the two together, and I believe we have a good case for concluding that our race descended from one monogamous couple.

Paul marks a dramatic comparison between Christ our new spiritual father, and Adam our father in the flesh. Christ is the single source of supernatural life, Adam stands opposite Christ as the single source of our race. Paul's comparison loses its punch when we oppose Christ against an initial population. The magnificent passage of Rom 5:12-21 is well focused as we read it: "For if many died through one man's trespass, much more have the grace of God and the free gift of the grace in that one man Jesus Christ abounded for many" (Rom 5:15). The focus would be diffused if we would read instead: "For if many died through one initial population's trespass..." The figure of Adam as the ancestor and figure of Christ has a significance in symbolism which likely makes it a part of our deposit of faith. Since Adam is a figure of Christ, he is one man, not a population. The argument is not conclusive but it is persuasive.

Finally, from a practical point of view, a corporate sin by an enclosed population does not fit into the picture of the first offense of man against God very well. Some might suggest that an entire group might have sinned in an agreement of mutiny and rebellion. But if a population committed the sin as one corporation, would that same population also repent as one corporation? According to the Bible, Adam and Eve made their peace with God after the Fall. Would an entire population do that? Would they all sin, then all repent, as though they were a mechanically controlled machinery of robots? That strains our sense of credibility. It is easier to believe that one couple sinned and then repented, than to assume that an entire population sinned today and then an entire population repented tomorrow.


The final word may not yet have been spoken, but as things stand today, we have no compelling reason to disown a monogamous couple, whom we conventionally name Adam and Eve, as our primal human ancestors. We would not improve the narration of the Bible on the one hand, nor scientific theory on the other, by naming Adam and Eve a population.

Next Page: Chapter 5: The Sin as Related in Genesis
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