Multilevel Selection Theory

Abstract

Multilevel Selection (MLS) Theory is a theoretical framework that presumes that selection can occur at an array of organizational levels from the gene upwards. MLS theory is the synthesis of individual selection as popularized by researchers including Williams (1966) and group selection as championed by researchers including DS Wilson (1975). More precisely, MLS theory offers a pluralist and flexible analytical framework that recognizes that selection occurs at different levels of organization as a function of context. As Wilson and Sober (1994) illustrated, when there is both phenotypic uniformity and shared fate at a given level of organization, then selection can be expected to occur. Consequently, if there is no phenotypic uniformity or shared fate among individuals in a given set of individuals, then one would expect selection to occur at the level of individuals. On the contrary, if individuals in a given set do share a common fate with one another and demonstrate phenotypic uniformity, then one would expect selection to occur at the level of sets wherein sets are being selected across evolutionary time relative to other sets in a given population of sets.

Keywords: Evolutionary Theory, Group Selection, Inclusive Fitness Theory, Individual Selection, Kin Selection