Bees and Flowers

28 Jun 2016

Bees and electricity feature in this month's Thunderbolts videos - go to ... but we also have the same subject but more nuanced at ... in which the aforesaid Dr Wile, a Creationist rather than an EU advocate, begins by saying that flowers attract bees by a variety of means including flower shape, scent, colour and ultra-violet reflection patterns. The point is that electricity is one of several factors that make up the relationship between flowers and pollinating insects. It also has a specific role that could have developed long after bees became bees.

Back in 2013 a group of researchers looking into the relationship between bees and flowers (the pollen) found that flowering plants developed a negative charge, and importantly, different species of flowers produce different patterns of negative charge. Bumblebees use these patterns to help them identify the host source of nectar and pollen. The same researchers have, since 2013, found out further facts and report how bumblebees detect the electrical charge displayed by flowers. They use filiform hairs that cover their bodies and these are designed to detect motion and sound - but they also respond to electric fields.

Bees are positively charged so when they land on flowers they tend to neutralise some of the negative charge in the flower. This changes the electric field so that when the bee leaves the pattern remains changed until the flower can replenish the negative charge. Therefore if another bee visited the same flower the alterned patter will tell it that a bee had already visited the flower and therefore there sin't a great deal of nectar or pollen to be had. It can then seek out a flower untouched by other bees. This is remarkable but extremely useful to bees as a whole - especially to hive bees. It saves energy and improves efficiency which to a hive bee must be very important as multiple bees would be on the wing seeking out flowers and pollen. It is also very useful to lone bees such as bumblebees as in the spring, for example, flowers are in short supply and therefore it is important not to waste time and energy flying in search of nectar that has already been depleted.

It seems that some moths, if not most moths (and probably butterflies too) may use electricity as advanced by Eric Laithwaite in 1960. Do other pollinating insects use electricity - hover flies for example. If so why do flies and bees and various insects become entrapped when entering a house or greenhouse and are apparently unable to find the door or window that was open for them to enter - no matter how big the door might be. They all seem to get trapped at ceiling or greenhouse roof level and are seemingly not programmed to zoom down a bit and then out of the window etc.