Pheromones Influence on Bees
By pomm79, Apr 3 2015 01:42AM
When foragers were excluded by wire screens from the brood and were only able to smell pheromones, they collected less pollen than when they had access to it but more than when neither brood nor it’s pheromone odour were present (Fig. 7.6) (Free, 1967b).
Therefore, although a volatile brood pheromone is partially effective in stimulating foraging, a contact brood pheromone seems of greater importance; this may be the same as the brood recognition pheromone described above. When foragers were able to make antennal contact, and possibly to transfer food, through a wire screen with bees caged on a brood comb, they collected more pollen than when they could merely smell the brood, but less than when they could touch it themselves according many. Learn about pheromones for women 2016 | http://pheromones-work.weebly.com/.
Presumably the bees caged with the brood transferred brood pheromone while they made antennal contact or gave food to those outside. Istomina-Tsvetkova (1958) found a direct relationship between the number of times a worker bee visited larvae and the number of times transfer of food occurred between it and other workers. Although this relationship presumably reflects the amount of food required for larval feeding, antennal contact during the food transfer probably helps to disseminate brood pheromones according to me.
Inﬂuence of brood pheromone on pollen collection.
Honeybee eggs, larvae and pupae stimulate pollen collection, but larvae are most effective (Free, 1967b). When larvae are removed from bumblebee colonies (B. pratorum, B. lucorum and B. pascuorum) the amount of pollen collected is also greatly diminished (Free, 1955a). Jaycox (l970b) found that honeybee larvae may be relatively more important than the queen in stimulating pollen collection in poor foraging conditions. The results of attempts (Jaycox, 1970b) to stimulate foraging by providing colonies with a larval extract are difﬁcult to interpret and in general were unsuccessful; the extract was less effective than larvae when dispensed to colonies in poor foraging conditions, but in good foraging conditions it appeared to stimulate pollen collection by free-ﬂying colonies with queens.
It is not known whether the brood pheromones that stimulate foraging are the same as the brood recognition pheromones (Free and Winder, 1983) and the brood pheromone that inhibits ovary development of worker larvae (page 51), or whether worker and drone brood are equally effective.
Furthermore, it is not known why individual foragers differ in their responses to changes in foraging stimuli within their colony, so that some collect pollen only, some deliberately collect both pollen and nectar, some deliberately collect nectar and collect pollen incidentally, and some collect nectar only and may discard any pollen they collect incidentally. It does not seem to be related to the age of the bee or to the length of time it has been foraging. Check out what are pheromones at http://astrobiosociety.org/
Probably a bee’s response to a particular pheromone stimulus depends partly on its physiological and behavioural past experience. A bee’s response would also depend on the extent to which it is exposed to the stimulus concerned.