AbstractWorker-male conflict in different bumble bee species is strongly associated with tendency, toward inbreeding. It is hypothesized that the major cost imposed by inbreeding arises from the production of diploid males in place of workers, during the early phases of colony development. The consequent dilution of the labour force slows down colony growth and leads to ultimate reduction in reproductive success. An experiment to test this hypothesis is described, using consanguineously mated queens of B. atratus Fkln. Colonies yielding a 1:1 mixture of males and workers grew significantly more slowly than normal all-worker producing colonies, providing support for the hypothesis.
Colony Development and Reproductive Success of Bumblebees in an Urban Gradient