Honey Bee Biology Workshop 1. The bee colony 2. Behavioral sequence of workers 3. Worker-queen differentiation 4. Honey bee dances 5. Chemical communications The Queen Longevity: 1-3 years 1. The mother of all other members 2. Can lay about 1,500 eggs per day 3. Has chemicals to let workers know she is around. 3. Rarely sting (no barbs). 5. Normally only 1 Queen per colony. The Drone Lives 21-34 days 1. Larger eyes, fuzzy body 2. Can not sting! 3. Does not participate any work 4. Dies during mating 5. Usually kicked out by workers in the fall 6. Anywhere 0-3,000 in a colony. 1
The Workers 1. Smallest members 2. Do all the work! 3. They sting! 4. 20-80,000 per colony. Lives 20 days to 7 months. Development Times Stage Egg larvae pupae Total worker 3 6 12 21 drone 3 7 14 24 Queen 3 5 8 16 Worker bees: morphological development days since egg-laying 1-3 4-8 9-20 21 2
Development in a Sealed Cell Molt to pupa Adult apolysis begins Adult eclosion larva prepupa pupa pharate adult adult 1 2 3 4 5 6 7 8 9 10 11 DAYS POST CAPPING Honey Bee Biology Workshop 1. The bee colony 2. Behavioral sequence of workers Worker bees: behavioral development Days since emergence 2-10 11-20 21-35 3
Age-related activities of workers First 2 days: cell cleaning 3-10 days: queen care nursing (feeding young) wax work 15-20 days: wax work nectar processing guarding undertaking 21-35 days foraging (water, nectar, pollen, propolis) colony defense (soldering) Workers would look for the right cell to work Feeding a larvae ( nursing ) 4
Rearing a new queen Queen cells are peanut-shaped & sized Queen retinue 5
Wax work Rare job: Guarding the entrance Rare job: Undertaking: It is a dirty job, but someone has to do it! 6
Air-conditioning a hive Receiving the nectar donor receiver Processing nectar into honey 7
The last job: foraging Mechanisms of Division of Labor Juvenile hormone is involved in the behavioral transition Juvenile hormone: keep caterpillars "juvenile" Metamorphosis: JH Molting hormone 8
Juvenile hormone is low in nurses, but high in foragers Huang et al. 1991 Mechanisms of Division of Labor Juvenile hormone is involved in the behavioral transition Rate of behavioral development and tendency to do rare tasks depend on paternity DRONE QUEEN DRONE SUBFAMILY SUBFAMILY 9
Mechanisms of Division of Labor Juvenile hormone is involved in the behavioral transition Rate of behavioral development and propensity to do rare tasks depend on genetics How soon a worker becomes a forager depends on the extent she "socializes" Foragers prevent young bees from "growing up" Flexibility of age of first foraging In a colony made up of entirely young bees, workers start foraging 5-7 days old, instead of ~21 days old. Removing foragers from a colony encourages younger bees to start foraging early Confining bees in a colony makes young bees "grow" slower -- they forage later In a colony made up entirely of foragers, some bees will "revert" to become nurses! A social inhibition model was developed 10
This model explains 3 forms of plasticity Huang & Robinson, 1992 PNAS Perhaps transferred to others from foragers via mutual feeding Cover photo of Proceedings of National Academy of Sciences (12/14/04) Honey Bee Biology Workshop 1. The bee colony 2. Behavioral sequence of workers 3. Worker-queen differentiation 11
Queen-Worker differentiation: Workers and queens are genetically identical, but phenotypically different: Royal jelly vs. worker jelly Young worker larvae (1-3 days old) can be changed into queens, if fed royal jelly (popular in Asia!) Food --> JH --> differential gene expression 12
Honey Bee Biology Workshop 1. The bee colony 2. Behavioral sequence of workers 3. Worker-queen differentiation 4. Honey bee dances Bees need to exploit floral resources efficiently, but they do not have a languag Bee bee tree at MSU with many bees (photo by Walt Pett) Or so we thought Bees cannot talk, but they can dance! 13
The direction to food is encoded in the direction of waggle (straight up = toward the sun) Distance to food is encoded in the duration of the waggle run Video from nova website QuickTime and a Sorenson Video decompressor are needed to see this picture. 14
Honey Bee Biology Workshop 1. The bee colony 2. Behavioral sequence of workers 3. Worker-queen differentiation 4. Honey bee dances 5. Chemical communications Retinue behavior: workers surrounding, licking and feeding her 1. Queen Mandibular Pheromone 15
Queen Worker Queen Mandibular Pheromone two types of effects: 1). Releaser effect (immediate behavioral response): Retinue behavior (to workers) Sex attraction during mating (to drones) Swarm stabilization (to both) 2). Primer effect (delayed, physiological/behavioral response) Inhibiting swarm cell construction Inhibiting swarming process Inhibiting worker ovary development Delay foraging age in workers Simulating foraging and brood rearing 2. Brood pheromone 16
FATTY ACID ESTERS IDENTIFIED ON THE LARVAE methyl and ethyl Palmitate methyl and ethyl Stearate methyl and ethyl Oleate methyl and ethyl Linoléate methyl and ethyl Linolénate C 15 H 31 COO-R C 17 H 35 COO-R C 17 H 33 COO-R C 17 H 31 COO-R C 17 H 29 COO-R R = -CH 3 R = -C 2 H 5 LE CONTE et al, 1989 Science, 245, 638-639 Dummies containing the different esters Parafin blocks (with brood pheromone) induce capping behavior LE CONTE et al. Naturwissenschaften, 1994, 81, 462-465. 17
Effects of Brood Pheromone Releaser 1. As cues for brood capping (hey, I am ready to be capped) 2. As kairomone for the Varroa mite (signal for mite entering) 3. Stimulate pollen collection Primer 1. Inhibit worker ovary development 2. Stimulate development of hypharyngeal glands 3. Increase royal jelly production 4. Delay foraging and inhibit juvenile hormone levels 3. The Worker Inhibitor 4. Alarm pheromones Mandibular gland: 2-heptanone Sting glands: isopentyl acetate. 18
5. Nasonav Pheromone isomers of citral, nerol, geraniol, nerolic acid, geranic acid and farnesol. 5. Nasonav Pheromone Components: isomers of citral, nerol, geraniol, nerolic acid, geranic acid and farnesol. Important for orientation when colony is disturbed, or during swarming 19