Genetical Research

Research Article

The effect of population size on effective population size: an empirical study in the red flour beetle Tribolium castaneum

Leslie A. Praya1, Charles J. Goodnighta1, Lori Stevensa1, James M. Schwartza1 and Guiyun Yana1

a1 Department of Biology, University of Vermont, Burlington, Vermont, USA


Despite the increasing number of studies on the magnitude of Ne/N ratios, much remains unknown about the effects of demographic and environmental variables on Ne/N. We determined Ne/N for seven population size treatments, ranging from N = 2 to N = 960, in the red flour beetle Tribolium castaneum. Ne/N decreased with increasing N, as evidenced by a significant negative relationship between log N and Ne/N. Our results are consistent with other published data on the relationship between Ne/N and N. Effective population sizes in large populations may be much smaller than previously recognized. These results have important implications for conservation and evolutionary biology.

(Received November 21 1995)

(Revised April 18 1996)