Unit of selection and Confirmation of Evolutionary Theory" provides a basic "philosophical" introduction to the debate. Below, cases of selection at the genic, cellular, individual and group level from within the multi-level selection perspective are presented and discussed. George C. Williams in his influential book "Adaptation and Natural Selection" was one of the first to present a gene-centered view of evolution with the gene as the unit of selection, arguing that a unit of selection should exhibit a high degree of permanence. Richard Dawkins has written several books popularizing and expanding the idea. According to Dawkins, genes cause phenotypes and a gene is
The Edge of Evolution for much of the diversity of life. It is Behe's second intelligent design book, his first being "Darwin's Black Box". While the book has been well received by creationists and non-biologists, reviews by certain scientists, especially those working in the field of biology, have been highly critical of Behe's methods, information and conclusions in the book. Behe begins the book with an observation that the theory of evolution consists of a coherent relationship of three related ideas: common descent, natural selection, and random mutation. He continues by stating he believes they are distinct ideas, with implications for the theory as