One common theme in deconversion stories is the loss of faith when the former believer discovered that contrary to what their faith community had dogmatically asserted, the evidence for evolution was in fact overwhelming. Unfortunately, one of the biggest reasons behind the perception that evolution and Christianity are utterly incompatible is the doctrine of Original Sin, in both its Reformed and Catholic forms. The fundamental problem here is of course the fact Original Sin requires every single human being to be exclusively descended from two people in order for the physical change in human nature that adherents of Original Sin believe happened as a result of Adam's sin to be genetically transmitted to the entire human race. Given what we know of the origins of the human race, this is of course impossible as the size of the human population has never been lower than a few thousand people, while humans and chimpanzees share a common ancestor that lived around six million years ago. Original Sin demands a view of human origins that cannot be reconciled with hard facts.
In a recent article [1] at the Recovering from Religion blog Ex-Communications, Suze Ambs writes on how discovering the truth about evolution helped erode her faith. While she states that there were many reasons for her deconversion, in this article she points out how the scientific evidence for human evolution was the "nail in the coffin" for her belief because it directly undermined Original Sin and the atonement theory based on it. Ambs' observation is hardly isolated, with other ex-Christians also pointing out how evolution destroys the anthropology of Original Sin and any atonement theory based on it. As such, it is worth looking at her article in some detail, if only to show just how dangerous to faith evolution denialism and Original Sin are.
