The effect of genotype, age, sex, and caste on response thresholds to sucrose and foraging behavior of honey bees (Apis mellifera L.)

Bees derived from artificially selected high- and low-pollen-hoarding strai ns were tested for their proboscis extension reflex response to water and v arying sucrose concentrations. High-strain bees had a lower response thresh old to sucrose than low-strain bees among pre-foragers, foragers, queens an d drones. Preforaging low-strain workers showed ontogenetic changes in thei r response threshold to sucrose which was inversely related to age. High-st rain foragers were more likely to return with loads of water compared to lo w-strain foragers. Whereas low-strain foragers were more likely to return w ith loads of nectar. Low-strain nectar foragers collected nectar with signi ficantly higher sucrose concentrations than did the high-strain nectar fora gers. Alternatively, low-strain foragers were more likely to return empty c ompared to high-strain foragers. These studies demonstrate how a genotypica lly varied sensory-physiological process, the perception of sucrose, are as sociated with a division of labor for foraging.