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Evolution of Cooperation
Individuals of the social spider Stegodyphus dumicola (Eresidae) feeding on a grasshopper.

Our understanding of evolution has been developed by using models, mathematical or computational descriptions of evolutionary processes in various levels of abstraction or detail. Based on early work by Ronald Fisher [3] and J.B.S. Haldane [4], William D. Hamilton formalized a model [5-6] that allowed traits to be selected that do not necessarily cause an individual to maximize its own number of offspring, but could instead cause it to help a closely related individual at the expense of its own reproductive potential.

This process is called "kin selection," a term coined by J. Maynard Smith [7]. Hamilton's model quickly became an ubiquitous tool for evolutionary biologists. It is based on the gene-centered view of evolution, explained in Richard Dawkins’s book, The Selfish Gene [8]. According to this approach, under some conditions, when an individual helps close kin reproduce, because they have a large number of genes in common, more copies of a gene may be made than by selfish behavior.

However, NECSI research has shown that the gene-centered view is based on a mean-field approximation. One assumes in mean-field approximation that each part of a system – in this case a particular gene of an individual – experiences the same conditions, also called "context." In traditional evolutionary models, this context is often simply the proportion of different types of individuals, or different gene combinations. Hence, these models describe evolutionary population dynamics as changes in gene frequencies from one generation to the next in the population as a whole.

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