The Units of Evolutionary Transition

Abstract

Maynard Smith’s analysis of units of evolution is compared to traditional approaches generalizing Darwin’s princi- ples. Maynard Smith’s key principle of multiplication is elaborated into a general account of the process of reproduc- tion that integrates concepts of heredity and development and is applicable to all levels of the biological hierarchy. The amended analysis suggests a new unit of evolution, the “reproducer,” which generalizes the concept of a replicator. The theory of evolutionary transition, the evolutionary origin of new levels of biological organization, is revised to reflect these amendments to the analysis of units.Athree-stage scenario for evolutionary transition is sug- gested.