title: Octopamine influences division of labor in honey bee colonies.
abstract: Forager honey bees have higher brain levels of octopamine than do bees tending larvae in the hive. To test the hypothesis that octopamine influences honey bee division of labor we treated bees orally with octopamine or its immediate precursor tyramine and determined whether these treatments increased the probability of initiating foraging. Octopamine treatment significantly elevated levels of octopamine in the brain and caused a significant dose-dependent increase in the number of new foragers. This effect was seen for precocious foragers in single-cohort colonies and foragers in larger colonies with more typical age demographies. Tyramine treatment did not increase the number of new foragers, suggesting that octopamine was exerting a specific effect. Octopamine treatment was effective only when given to bees old enough to forage, i.e., older than 4 days of age. Treatment when bees were 1-3 days of age did not cause a significant increase in the number of new foragers when the bees reached the minimal foraging age. These results demonstrate that octopamine influences division of labor in honey bee colonies. We speculate that octopamine is acting in this context as a neuromodulator.
authors.affiliation: Department of Entomology, University of Illinois at Urbana-Champaign, Urbana 61801, USA
authors.forename: D J
authors.initials: DJ
authors.lastname: Schulz
authors.forename: G E
authors.initials: GE
authors.lastname: Robinson
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000375:Aging / Q000502:physiology; D000818:Animals; D001516:Bees / Q000502:physiology*; D001522:Behavior, Animal / Q000187:drug effects*; D001679:Biogenic Amines / Q000494:pharmacology; D001923:Brain Chemistry / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000187:drug effects; D009655:Octopamine / Q000494:pharmacology*; D014439:Tyramine / Q000494:pharmacology
chemical_list: D000316:Adrenergic alpha-Agonists; D001679:Biogenic Amines; D009655:Octopamine; D014439:Tyramine