It’s a welcome sign to any beekeeper – and, surely, to their bees too – the ‘waggle dance’ that signifies a nectar flow. Science writer Dave Black puts on his dancing shoes to help us understand what is known about this peculiar language of the honey bee.
By Dave Black
Luckily, it’s not uncommon to open up a hive at this time of the season and see a dancing bee or two. We can only speculate about the origin of this curious behaviour. Some have suggested it started as a sort of aborted take-off on combs open to the sky, a six-legged mime with sound effects. The intended direction referenced the sun until, in cavity-nesting species, gravity substituted.
You have to be even older than me to remember that the idea that this was a form of communication was, until the early 1970s, still controversial. Karl von Frisch had been observing the dances and developing his dance language theory since the 1920s. Adrian Wenner was an electronics technician and biologist grounded in maths who thought he had been ‘indoctrinated’ by the status quo.
At the time (von Frisch’s observation was challenged in 1967, his Nobel Prize awarded in 1973) the idea that an invertebrate might have a language made no sense at all. According to Wenner, maybe the dance contained information, but it could not be assumed that foraging bees acted on it. In his opinion what bees were recruited by was odour. The difference between the protagonists was partly philosophical, nature in all its beauty or nature as an exercise in practical mechanics. Or, as someone else put it, “the bees talked to von Frisch, but only danced for Wenner.” It was an acrimonious debate, despite the scientific merits, enmeshed in personal and social differences, and not actually too dissimilar to the current ‘animals (bees) feel pain and deserve ethical care’ arguments. But that’s another story.
A tale of messages and messengers
Beekeepers studying the behaviour had seen that it varied between one species or sub species and another, and we had got used to talking about that as different ‘dialects’ (of the same language). What’s more, quite early experiments had shown, at least to some degree, the dialects were hereditable .
The aspect of the dances that differed was that the dances transitioned from one type to another to indicate different distances. As a rough example, A. m. ligustica (Italian bees - AML) would do ‘round’ dances for up to 10m, and ‘waggle’ dances for distances of 40m or more, where A. m carnica (Carniolans) would do round dances up to 20m, and waggles after 90m!
Besides the genetics, the local environment is also something that altered how dances were performed, but it was difficult to untangle the two factors. You would need to run colonies of different species at the same time in the same place, or run colonies populated by a mixture of species. Generally this just results in all-out war, but at least one study succeeded (for a while) with A. cerana queens and a mixture of AML and A.cerane cerana (ACC) workers. Mixtures built with AML queens imploded within a few days, those using ACC queens could be managed – but only just – for more than 50 days.
The study found that the workers did behave as expected, the directions in the dance were the same, but the distance indications were different. The attending bees were still able to find the food source regardless of the dialect they followed, even if it meant following the directional instruction and then searching. It looked as though attendants were more likely to follow a dance performed by a member of their own species, but the statistics were ambiguous, and there was cross-species recruitment going on. Despite the six to eight million years of evolution separating the two species, they were each able to ‘understand’ the others ‘language’ in a functionally useful way.
An enigmatic melody
Last year a study from some Chinese researchers fleshed out what’s really going one here. They set up two groups of five colonies with marked bees. One group were hives treated normally, the other group contained the experimental colonies. The experimental colonies only contained bees that were one day old, so the scientists were able to observe the dancing as the bees aged and compare the two groups. At first, the experimental bees could not follow any dances and their early dances were confused, directionally error prone, and never communicated distance accurately.
Distance measurement by honey bees (their ‘odometer’) is understood to use something called ‘optic flow’. That is, their eyes provide the brain with continuous information about how quickly objects, or the patterns of brightness and darkness objects cause, change as they pass through their visual field . That ‘flow’ of information about a flight experience then re-presents the data as a buzzy waggle run across the comb surface. It’s well established that following an average of all the dances for a given destination provides a very reliable relationship between the duration and strength of the waggle and the distance to the food source.
In both groups new bees that had not begun dancing (eight or nine days old) followed the dances of older (more than 12 days old) bees that had. It shouldn’t be a complete surprise that bees watch and learn things from each other – it has been demonstrated quite convincingly with bumble bees for example . What appears to happen is that, whatever their innate ability, it’s essential bees learn to ‘calibrate’ their dances by watching older foragers. They can’t do that when there are no older foragers though.
The nature of what the ‘calibration’ is, is a bit of an enigma. It isn’t happening as a result of a failure to communicate, because the dance watchers are not testing the ‘instructions’ at all, they’re just watching. What’s more, although watching improves the dances, young bees that grow up without a tutor never learn to encode distance accurately.
So, just as listening to a tonal language (Mandarin, Thai, Zulu, Punjabi etc.) as a child tunes your brain to hear and produce the perfect pitch, the buzz of the waggle dance loses its melody unless you’ve grown up with it.
Dave Black is a commercial-beekeeper-turned-hobbyist, now retired. He is a regular science writer providing commentary on “what the books don't tell you”, via his Substack Beyond Bee Books, to which you can subscribe here.
References
Munz, T., 2005. The Bee Battles: Karl von Frisch, Adrian Wenner and the Honey Bee Dance Language Controversy. J Hist Biol 38, 535–570. https://doi.org/10.1007/s10739-005-0552-1
Rinderer, T.E., Beaman, L.D., 1995. Genic control of honey bee dance language dialect. Theoret. Appl. Genetics 91, 727–732. https://doi.org/10.1007/BF00220950
Su, S., Cai, F., Si, A., Zhang, S., Tautz, J., Chen, S., 2008. East Learns from West: Asiatic Honeybees Can Understand Dance Language of European Honeybees. PLoS ONE 3, e2365. https://doi.org/10.1371/journal.pone.0002365
Dong, S., Lin, T., Nieh, J.C., Tan, K., 2023. Social signal learning of the waggle dance in honey bees. Science 379, 1015–1018. https://doi.org/10.1126/science.ade1702
Egelhaaf, M., 2023. Optic flow based spatial vision in insects. J Comp Physiol A 209, 541–561. https://doi.org/10.1007/s00359-022-01610-w
E. H. Dawson, A. Avarguès-Weber, L. Chittka, E. Leadbeater, Curr. Biol. 23, 727–730 (2013).
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