Posted on: 02 March, 2017
Author: Alexander P
The top pheromones in bees are important. Bees recruited to an attractive natural food source do not follow the dance directions very precisely (Von Frisch, 1967) nor is it desirable that they should ... The top pheromones in bees are important. Bees recruited to an attractive natural food source do not follow the dance directions very precisely (Von Frisch, 1967) nor is it desirable that they should do so. A natural food crop is usually distributed over a considerable area, and, if the arrival points of the recruits are also widely distributed, a colony can exploit it more efciently than if all its foragers concentrated on a small area. However, most naturally occurring water sites, other than early morning dew or rain, are more discrete than those of nectar and pollen and have less pronounced odours, and the exposure of the pheromone glands by foragers at such sites helps recruits to nd them sooner. It is not known whether bees expose their pheromone glands when foraging on dew or raindrops, but it is doubtful whether this would commonly occur as they are likely to evaporate before the bees make sufcient trips to begin scenting. The exposure of pheromones by bees foraging for nectar in glasshouses or on dishes of odourless sugar syrup is probably an adaptation of the behaviour that naturally occurs when collecting water.’ Perhaps dancing and Nasonov gland exposure are more closely correlated when A. mellzfera foragers are collecting water; this would be interesting to discover. All instances of pheromones release cited so far have occurred outside the nest itself, but it may also occur within the nest. I have seen workers in a glass-walled hive expose their pheromones glands when a sudden decrease in temperature has caused them to move together into a compact cluster according to http://worstthing.org/are-you-looking-for-the-top-pheromones/ Perhaps Nasonov pheromone is used to mark routes within the nest and particularly to food stores remote from the cluster. A path of fanning bees has been observed between the combs and a feeder containing sugar syrup inside the top of a hive (Jacobs, 1924). This behaviour was further studied by Levchenko and Shalimov (1975) who showed that the tendency of bees to scent increased with the distance between the combs and supply of sugar syrup. Nearly all the bees that scented did so while on the nal part of their pheromones. Although the bees were not found to expose their Nasonov glands as readily or as consistently when collecting water as when collecting concentrated sugar syrup, this may have merely reected the syrup’s relative attractiveness at the time, and perhaps when water is in greater demand scenting is more pronounced. In contrast to Nasonov release at the hive entrance (Ribbands and Speirs, 1953), that at a water site was not related to any difculty bees had in locating it Probably under natural conditions, Nasonov pheromone released by foraging bees is usually associated with water collection and not with nectar or pollen collection. This would also help explain why fanning is not associated with Nasonov release in these circumstances. The pheromones approach to the feeder; this seems anologous to Nasonov exposure by ying bees prior to landing at a source of water or food. Source: Free Articles from ArticlesFactory.com Alexander P is a blogger from Los Angeles who studies pheromones.