'can we doubt ... that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind?' In the Origin of Species (1859) Darwin challenged many of the most deeply held beliefs of the Western world. His insistence on the immense length of the past and on the abundance of life-forms, present and extinct, dislodged man from his central position in creation and called into question the role of the Creator. He