Thursday 27 November 2014

piping and dancing

It was the beekeepers' monthly association meeting this evening, and one of our members who is doing the exams and has got as far as bee communication had volunteered to share her freshly acquired knowledge with the rest of us.  We were very happy to take her up on the offer, since part of the group's ethos is that any member who knows more about a topic than most is warmly encouraged to spread their expertise around.  Apart from the saving on external speakers' fees, and the sheer implausibility of finding a professional expert on honey bee communication available to talk to a small group in north Essex on a Thursday night, active member participation is part of the division's philosophy.  The University of the Third Age works on the same principal.

Tonight's volunteer started from the useful position of teaching A level psychology.  While the syllabus doesn't include insect behaviour, it covers associative learning and stimulus response behaviour, and gives an overall framework that you might not have if you had only studied the bee behaviour module.  And being a trained teacher was a big plus, as was the fact that she is a hard working and conscientious person who had put an immense amount of work into preparing the talk, complete with video clips.

I did some of the intermediate level bee exams, but gave up after module five as I began to feel as though I really had sat enough examinations for one life time.  Bee behaviour is number six, and it was so interesting that I began to wish I'd stuck with them for at least one more.  They may have been redesigned since I did them, though.  The syllabus and exam questions used to be very old fashioned, the sort where you learn lots of facts and then produce the required facts against the clock, rather than being asked to use them to solve any kind of practical beekeeping problem.  I think it was honey bee physiology that did for me.  I couldn't see in what circumstances I was ever going to need to know the number of segments in a drone's antenna, or the names of its component parts.

Bee communication is complex.  It has to be, I suppose, when tens of thousands of individuals are combining to form a super-organism.  They communicate by sharing food, by their movements, by making sounds, and through a vast array of chemical signals.  It isn't the easiest thing to measure, either, given that bees naturally live in dark confined spaces.  I take my hat off to whoever managed to attach tiny tinfoil weights to foraging bees, measure their waggle dances as they reported back to the rest of the hive, and discover that they tended to overestimate distances when the physical effort of flying there and back was artificially increased by weighting them down.

On the other hand, sometimes the opposition between two simple effects can produce a complex outcome.  Queen bees give off a pheromone that inhibits the production of drones, while young workers (or was it worker brood?  I should have taken notes) give off a chemical signal encouraging it.  Early in the season, when there aren't many workers and the colony doesn't need drones, the queen anti-drone signal trumps the workers and the bees don't make drones.  As the season progresses and the number of workers rises, they now chemically outweigh the queen, and drones are raised just as the weather is getting warm enough for queens to fly and get mated, which is when drones are needed.  Come autumn when the number of workers declines, the anti-drone signal is stronger once again.  The bees don't make any more drones that year, and evict the ones they have from the hive.

Our speaker thought that bee communication was pretty sophisticated for three reasons.  Bees meet the basic criteria of performing deliberate communicative acts, but also the more demanding test of being able to communicate about items that are removed in time and space.  And she's right, the various dances performed by foraging bees tell other potential foragers the direction and distance of remote food sources the forager visited at a time now past.  As she said, your dog almost certainly can't do that.  The great apes can, and probably whales and dolphins, but dogs do not talk together about what they did yesterday or where they'll go tomorrow.  And thirdly, bees seem to have dialects, so that different hives or subspecies don't share exactly the same dances and can't immediately respond correctly to each other's signals, but they learn after a few days together.

I'm not sure that much of it helps me become a better beekeeper, at least in the short run.  After she'd played us recordings of young queens piping I knew I had heard that noise for real in the apiary, on the other hand by the time a hive contains young queens charging about and challenging each other, you have lost control of the swarming process anyway.  An in-hive detector that could analyse the colony noise and alert you as soon as they started to make any preparations for swarming at all, now that would be useful.

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