Noting that “[g]enetic diversity in the human population is not consistent with what we would expect if all humans had descended from a single pair of individuals,” Loren Haarsma grapples with what that means for the Christian understanding of original sin:
A variety of scenarios are being proposed by Christian scholars today for how we might understand the Adam and Eve of Genesis 2, and their disobedience in Genesis 3, in light of modern science. Some scenarios propose Adam and Eve as two individuals living in Mesopotamia just a few thousand years ago, acting not as ancestors but as recent representatives of all humanity. As our representatives, their disobedience caused all of humanity to fall into sin. Other scenarios propose Adam and Eve as two individuals, or as literary representations of a small group of ancient representative-ancestors, selected out of a larger population, living in Africa over 100,000 years ago at the dawn of humanity; they were ancestors—but not the sole ancestors—of all humans today; they fell into disobedience against God over a relatively short period of time with a fairly distinct “before” and “after.” Other scenarios propose that Adam and Eve’s disobedience in Genesis 3 is a symbolic retelling of the story of every human who, over our long history, became aware of God’s claims on how they ought to live, and then disobeyed.
Jerry Coyne snarks:
Adam and Eve couldn’t have been the literal ancestors of all humanity. Normally, such a scientific trashing of scripture could be absorbed, at least by liberal theologians. They’d just reinterpret Adam and Eve as metaphors. But that causes big trouble on two counts.