MALE MATING PREFERENCES AND ASSORTATIVE MATING IN THE SOLDIER BEETLE.

Abstract

Mating preferences for a color characteristic were examined in three northern Georgia populations of the soldier beetle, Chauliognathus pennsylvanicus De Geer, by comparing observed and expected frequencies of matings to the same phenotype. The three populations are apparently in a zone of secondary contact between disparate color morphs. In the most northern population sampled, preferences were strong and were associated with positive assortative mating with respect to the color characteristic. In the southern population, neither assortative mating nor mating preference was strong, while in the middle population, preferences were expressed in the absence of assortative mating. Mating preferences cannot be attributed to host-plant choice, microhabitat choice, or simple conditioning on the phenotype of the last mate. However, they may represent part of a specific mate-recognition system which has been maintained in part of the zone of overlap but which has eroded in other areas.