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 Selfish Gene some cases while positing selection at higher levels. Both sides agree that very favourable genes are likely to prosper and replicate if they arise and both sides agree that living in groups can be an advantage to the group members. The conflict arises in part over defining concepts: In "The Social Conquest of Earth" (2012), the entomologist E. O. Wilson contends that although the selfish-gene approach was accepted "until 2010 [when] Martin Nowak, Corina Tarnita, and I demonstrated that inclusive fitness theory, often called kin selection theory, is both mathematically and biologically incorrect." Chapter 18 of "The Social Conquest of