Some Background: The Book of Genesis says that Adam and Eve lived together, and dogma holds that they are the father and mother of the human race, the first humans from which all humans descended.
Scientific discovery, however, has been hesitant to affirm this. Indeed it would contradict evolutionary biology for science to say that Homo sapiens began with the sudden appearance of the first man and the first woman, the sole members of the species, from which all others descended.
To some people this is a troubling contradiction, but to others, like me, it is one of the most exciting intersections of science and theology. It is a topic that pushes a thinker to go beyond currently held assumptions. It helps to know, first, what must be held as absolutely true. I like to get that firmly in place.
What must be held true for Christians? The Catechism of the Catholic Church (CCC 390) states, “The account of the fall in Genesis 3 uses figurative language, but affirms a primeval event, a deed that took place at the beginning of the history of man. Revelation gives us the certainty of faith that the whole of human history is marked by the original fault freely committed by our first parents.” We must hold true that Adam and Eve existed and committed original sin. Pope Pius XII stated in Humani Generis (37) that polygenism must be rejected. Polygenism is the theory that there was a population of men and women instead of just one man and one woman, which is mongenism.
The International Theological Commission has stated that physical anthropology and molecular biology make a “convincing case” for the origin of the human species in Africa about 150,000-200,000 years ago in a “humanoid population of common genetic lineage.” The key word there is “humanoid” instead of “human”. A human person is body and soul, and dogma also binds us to hold true that the human soul is created immediately out of nothing by God, a special creation that did not evolve. That means the body may have evolved, hence the use of the word “humanoid”. A humanoid population would not be the same thing as a human population, in that humanoid bodies would not have human souls made in the image of God with the power of intellect and will, and thus would not be human. (Edited, see comments below.)
That speculation, for it is only that, leads to the conclusion that the human body evolved and about 150,000 years and God put a human soul in two bodies. Some strongly reject this, others do not. I just say that I don’t know, which is why I am so fascinated with these scientific and theological studies. Whatever happened, happened. We’re just trying to figure it out.
What must be held true for science? You can’t deny that the bodies of living things evolve. Genes mutate, and the organisms with those genetic mutations sometimes respond differently to the environment, which in turn affects how well they reproduce. That, in a sentence, is evolution.
The Science: Geneticists speak of ‘Y-chromosome Adam‘ and ‘Mitochondrial Eve‘. This refers to the ancestors to whom the Y chromosomes (a male) and mitochondrial DNA (a female) of humans alive today can be traced. Certain DNA sequences on Y chromosomes are passed down from father to son, and certain mitochondrial DNA is passed down from mother to daughter. Population studies predicts that we all have that genetic material in common from these two parents. That’s quite a mind-blowing scientific discovery in itself. It means that when geneticists analyze the DNA from people all around the world today, they find that all the men and women living now have DNA that appears to have belonged to one man and one woman, hence the Biblical reference — which, as you can guess, is troubling to a lot of non-Bible-liking people.
Scientists and theologians alike are quick to point out that this genetic discovery in no way scientifically proves that there was only one man and one woman from which all the human race descended; it doesn’t rule out the possibility scientifically that many men and many women could have existed, and that only the lineage of that one man and one woman survived while all the other relatives died and did not continue to reproduce up to the present day.
But still — sounds pretty Biblical, huh?
The New Study: The research showed, however, that this Mitochondrial Eve probably lived in Africa around 200,000 years ago, but this Y chromosome Adam only lived about 100,000 years ago. They did not appear to have lived in the same time, which make it hard to picture them in the Garden of Eden together.
This data is obtained by “molecular clock” calculations that estimate the time to the most recent common ancestor, calibrated with archaeological findings. A team recently at the University of Sassari, Italy, led by geneticist Paolo Francalacci studied the Y chromosomes of 1,200 men from the island of Sardinia, and recalibrated the molecular clock. Get this: Their findings suggest that Adam lived 180,000-200,000 years ago, putting Adam in the same time as Eve. The most recent data is reviewed here: Genetic Adam and Eve did not live too far apart in time, Nature, August 6, 2013.
So now there’s that.
This is a conceptual diagram of the lineage to Mitochondrial Eve. Is that Y chromosome Adam standing next to her? Maybe we’ll see.