THE RELATION BETWEEN DISPERSAL BEHAVIOR AND REPRODUCTIVE FITNESS IN THE FLOUR BEETLE TRIBOLIUM CASTANEUM

Abstract

Assuming that dispersal from optimal environments evolved as a colonizing device, it is expected that dispersants will possess reproductive characteristics enhancing the probability of successful colonization. Two approaches were used to clarify the relationship between dispersal behavior and 2 major components of reproductive fitness (developmental time and fecundity) in the flour beetle T. castaneum: comparison between 2 lines, one selected for low dispersal and the other selected for high dispersal, for several components of reproductive fitness, and calculation of the correlation coefficients between each fitness component investigated and dispersal behavior. The results obtained by both approaches indicate shorter developmental time and higher fecundity for dispersants than for nondispersants.