ABSTRACT

The role of random drift in twentieth century evolutionary biology has been a turbulent one. Biologists such as Wright and Fisher disagreed over the relative importance of random drift in the evolutionary process, with Fisher arguing that Wright's theory assigned too great a role to random drift. The debate continues today, with "neutralists" such as Kimura and Crow claiming an even larger role for random drift than Wright did, while "selectionists" such as Ernst Mayr and Douglas Futuyma (see especially Mayr 1983 and Futuyma 1988) remain steadfast to the idea that it is natural selection that plays the preeminent role in phenotypic evolution. According to the selectionist camp, the role of random drift is at best a minor one. As Beatty (1984) argues, this debate has taken place in specific contexts (over whether, for example, natural selection or random drift is more prevalent in a particular population) as well

as more general contexts (over whether natural selection or random drift is more prevalent as a whole).