RELATEDNESS AMONG HONEYBEES (APIS-MELLIFERA) OF A DRONE CONGREGATION

The honeybee (Apis mellifera) queen mates during nuptial flights, in t he so-called drone congregation area where many males from surrounding colonies gather. Using 20 highly polymorphic microsatellite loci, we studied a sample of 142 drones captured in a congregation close to Obe rursel (Germany). A parentage test based on lod score showed that this sample contained one group of four brothers, six groups of three brot hers, 20 groups of two brothers and 80 singletons. These values are ve ry close to a Poisson distribution. Therefore, colonies were apparentl y equally represented in the drone congregation, and calculations show ed that the congregation comprised males that originated from about 24 0 different colonies. This figure is surprisingly high. Considering th e density of colonies around the congregation area and the average fli ght range of males, it suggests that most colonies within the recruitm ent perimeter delegated drones to the congregation with an equal proba bility, resulting in an almost perfect panmixis. Consequently, the rel atedness between a queen and her mates, and hence the inbreeding coeff icient of the progeny, should be minimized. The relatedness among the drones mated to the same queen is also very low, maximizing the geneti c diversity among the different patrilines of a colony.