GENETIC-DETERMINANTS OF HONEY-BEE FORAGING BEHAVIOR

The amount of pollen stored in honey bee, Apis mellifera, colonies is a selectable trait. Five generations of two-way selection resulted in high and low strains that differed more than six-fold in quantities of stored pollen. Comparisons with hybrid crosses suggested that colony- level, high pollen-hoarding behaviour is inherited as a recessive trai t. Colony levels of stored honey, however, showed an over-dominant pat tern, with hybrid colonies storing significantly more honey than eithe r of the selected strains. Controlled studies of individual foraging b ehaviour revealed the same patterns of inheritance at the individual l evel: high-strain workers specialized on pollen foraging, low-strain w orkers on nectar, and hybrid workers demonstrated a significantly grea ter nectar-collecting bias than workers of the low strain. Genomic map ping studies of colony-level pollen hoarding and individual foraging b ehaviour have revealed two genomic regions of the honey bee that conta in major quantitative trait loci that explain a large portion of the o bserved variance in pollen hoarding and foraging behaviour of the two strains. The effects of major genes on within- and between-colony vari ation in individual foraging behaviour are discussed in the context of conducting and interpreting empirical tests of foraging theory. (C) 1 995 The Association for the Study of Animal Behaviour