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 the benefit of the behaver, but whether it is to the benefit of the gene "G" ...With altruism this will happen only if the affected individual is a relative of the altruist, therefore having an increased chance of carrying the gene. An extended discussion of Dawkins' views and his book "The Selfish Gene" is provided by Wilkins and Hull. Dawkins begins by discussing the altruism that people display, indicating that he will argue it is explained by gene selfishness, and attacking group selection as an explanation. He considers the origin of life with the arrival of molecules able to replicate