Posted on: 02 March, 2017
Author: Alexander P
Bees love to use the top pheromones to increase pollination. Furthermore, bees are able to distinguish between the heads alone of bees of their own colony and heads of bees of alien colonies; they pre... Bees love to use the top pheromones to increase pollination. Furthermore, bees are able to distinguish between the heads alone of bees of their own colony and heads of bees of alien colonies; they prefer to beg food from the former and may even attack the latter without pheromone attraction. (Free, 1956). Even colonies in the same location make different use of the local ora, and Kalmus and Ribbands (1952) argued that slight differences in the quality of trail pheromones being used in different colonies was sufcient to impart differences in colony pheromone odour. They supposed that because of the extensive transfer of food between the members of a colony, each one would have an almost identical diet, would ingest a similar mixture of the nectars collected, and that odorants associated with the mixture would be passed to the epicuticle and form the basis of the pheromone colony odour. Although at any one time all the workers of a colony would emit a similar odour, this would change with the colony's incoming food supplies. In support of their hypothesis they demonstrated that a change in colony pheromone odour could be induced by a rather drastic change in food supply. Dividing a colony into two equal parts and feeding one part with a mixture of black treacle and heather honey soon resulted in it acquiring a different pheromone odour from the unfed part. Conversely, Ribbands (1953) found that taking colonies (whose food stores he had removed) to an area where heather was the only source of forage, resulted in all the colonies acquiring the same colony odour and the bees being unable to distinguish between members of their own and other colonies. This includes a female pheromones compound. An alternative suggestion (Butler and Free, 1952) was that distinctive pheromone odours arise by adsorption of odours present in the hive atmosphere onto the waxes of the body surface. This alone could have accounted for changes in colony odour when, in the above experiments, colonies were given food with a strong aroma. It would also explain why intruders that had managed to remain in alien colonies for only one or two hours appeared to have acquired the pheromone odour of the bees of the adopted colonies and were no longer treated as alien. Experiments by Renner (1955, 1960) provided evidence for this suggestion. He showed that the odour alone of black treacle in a hive was enough to change the colony odour even when the bees could not feed on it. He also obtained Nasonov pheromone, free from other pheromone scents, by wiping Nasonov glands with small pieces of lter paper and showed that (contrary to previous supposition) it was not specic for race or colony, so the Nasonov gland is unlikely to be a source of colony odour. More recent work (page 121) has failed to find any difference in the composition of Nasonov pheromone components of different races of honeybees. Foraging experiments are needed in which foragers choose between their own and other colony odours deposited by bees that have not exposed their Nasonov glands. Article Tags: Bees Love, Increase Pollination, Pheromone Odour, Colony Odour Source: Free Articles from ArticlesFactory.com Alexander Pommett is a blogger from Los Angeles that studies pheromones.