John Stott writes the following in his commentary on Romans:
We should certainly be open to the probability that there are symbolical elements in the Bible's first three chapters. The narrative itself warrants no dogmatism about the six days of creation, since its form and style suggest that it is meant as literary art, not scientific description. As for the identity of the snake and the trees in the garden, since 'that old serpent' and 'the tree of life' reappear in the book of Revelation, where they are evidently symbolic, it seems likely that they are meant to be understood symbolically in Genesis as well. But the case with Adam and Eve is different. Scripture clearly intends us to accept their historicity as the original human pair . . . Paul told the Athenian philosophers that God had made every nation 'from one man' (Acts 17:26); and in particular Paul's carefully constructed analogy between Adam and Christ [see Romans 5:12-21] depends on its validity on the equal historicity of both. He affirmed that Adam's disobedience led to condemnation for all, as Christ's obedience led to justification for all (Rom. 5:18).
Moreover, nothing in modern science contradicts this. Rather the reverse. All human beings share the same anatomy, physiology and chemistry, and the same genes . . . This homogeneity of the human species is best explained by positing our descent from a common ancestor. 'Genetic evidence indicates', writes Dr Christopher Stringer of London's Natural History Museum, 'that all living people are closely related and share a recent common ancestor.' He goes on to express the view that this common ancestor 'probably lived in Africa' (though this is not proved) and that from this ancestral group 'all the living peoples of the world originated'.