I affirm that God is the creator of the universe and human beings, who are his image-bearers. I affirm the historical existence of Adam and the doctrine of original sin. But I am agnostic on the questions of how and when Adam was created. By “agnostic” I mean having a doubtful or noncommittal attitude. I believe, in principle, that the biblical doctrine of creation is compatible with evolutionary theory, as Christian philosopher Alvin Platinga writes:
A more important source of conflict has to do with the Christian doctrine of creation, in particular the claim that God has created human beings in his image. This requires that God intended to create creatures of a certain kind—rational creatures with a moral sense and the capacity to know and love him—and then acted in such a way as to accomplish this intention. It does not require that God directly create human beings, or that he did not do so by way of an evolutionary process, or even that he intended to create precisely human beings, precisely our species. (Maybe all he actually intended to create were rational, moral, and religious creatures; he may have been indifferent to the specific form such creatures would take.) But if he created human beings in his image, then at the least he intended that creatures of a certain sort come to be, and acted in such a way as to guarantee the existence of such creatures. This claim is consistent with the Ancient Earth thesis, the Progress thesis, the Descent with Modification thesis, and the Common Ancestry thesis. It is important to see that it is also consistent with Darwinism. It could be, for example, that God directs and orchestrates the Darwinian process; perhaps, indeed, God causes the right genetic mutation to arise at the right time. There is nothing in the scientific theory of evolution to preclude God from causing the relevant genetic mutations. What is not consistent with Christian belief, however, is the claim that this process of evolution is unguided—that neither God nor anyone else has had a hand in guiding, directing, orchestrating, or shaping it. 
I believe, in principle, that we can integrate the historical Adam with the scientific evidence of evolution, as C. S. Lewis writes:
For long centuries God perfected the animal form which was to become the vehicle of humanity and the image of Himself. He gave it hands whose thumb could be applied to each of the fingers, and jaws and teeth and throat capable of articulation, and a brain sufficiently complex to execute all the material motions whereby rational thought is incarnated. The creature may have existed in this state before it became man: it may even have been clever enough to make things which a modern archaeologist would accept as proof of its humanity. But it was only an animal because all its physical and psychical processes were directed to purely material and natural ends. Then, in the fullness of time, God caused to descend upon this organism, both on its psychology and physiology, a new kind of consciousness which could say ‘I’ and ‘me,’ which could look upon itself as an object, which knew God, which could make judgments of truth, beauty, and goodness, and which was so far above time that it could perceive time flowing past. . . . We do not know how many of these creatures God made, nor how long they continued in the Paradisal state. But sooner or later they fell. Someone or something whispered that they could become gods—that they could cease directing their lives to their Creator. 
 Alvin Plaintinga, “Science and Religion: Why Does the Debate Continue?”, in The Religion and Science Debate: Why Does It Continue?, ed. Harold W. Attridge (New Haven: Yale University Press, 2009), 106-107.
 C. S. Lewis, The Problem of Pain (New York: HarperOne, 2001), 72, 75.
- Timothy Keller, Creation, Evolution and Christian Laypeople (BioLogos Paper)
- Bruce Waltke, Barriers to Accepting the Possibility of Creation by Means of an Evolutionary Process (BioLogos Paper)