The Selfish Gene is a book by Richard Dawkins explaining a gene-centric theory of evolution. Unlike many previous theories, which explained natural selection as survival of the fittest organism or fittest species, Dawkins understands evolution as the survival of specific genes. In doing so, Dawkins is able to explain phenomena that these other theories could not account for, including altruism and eusocial behavior, drawing on game theory to explain "evolutionary stable strategies" (ESS) of such behaviors that group selection theories (theories based on group or species survival) could not produce.
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