Our first talk of last week’s conference was given by bee farmer Dan Basterfield and was all about honey bee dances and ‘The dance language controversy’.
Dan grew up with beekeeping around him and now helps to run the family beekeeping business in Devon, expanding the business and building a brand new honey farm.
He is an active member of the Bee Farmers Association, was trustee and Chairman of the International Bee Research Association, is a BBKA Master Beekeepers and Examiner; and holds the National Diploma in Beekeeping. He runs 120 – 140 double brood Modified Commercial hives, migrating between various farm crops in East Devon, and raises queens for prolific, productive and healthy qualities. Outside the beekeeping season, Dan undertakes teaching for the BBKA and NDB.
What is the dance language controversy?
Dan began by explaining that he was surprised to hear Tom Seeley make a casual comment along the lines of: ‘Of course, there’s really only one honey bee dance’. The standard information given by beekeeping books is usually that there’s at least two or three: the direction-less round dance, saying ‘go out and look for it’ for forage within 15m of the hive; sometimes included is the transition dance, for food between 15-100m away; and the famous waggle dance, giving directions for food over 100m away.
Dan decided to investigate Tom’s comment further – in fact, his talk took us all the way back to 1744!
John Thorley (1744)
“Bees certainly have a language among themselves which they perfectly understand, tho’ we do not, or at best do very imperfectly.”
I love those old beekeeping quotes. Dan used this quote while explaining that we have gained an ever better – but still imperfect – view of the dances since then. He said that what he loves about bees is that the deeper you dig, the more there is to look at, the more little tangents they send you off on.
The discovery of the waggle dance
Karl von Frisch won his Nobel prize for decoding the dance language of bees. Just two years into his research career, in 1914 the young von Frisch published a paper demonstrating that bees could see in colour, through an elegant experiment that trained bees to go to syrup on a blue square. By 1923 he had produced a paper which described ’round’ and ‘wagtail’ dances. And in 1946 he published the book “Die Tänze der Bienen” (The dances of the honey bee), which described two dances, round and waggle. At the time it was a quite revolutionary discovery that bees had their own crude language.
Other experiments since have reinforced von Frisch’s discovery that the waggle dance indicates the direction of the nectar or pollen in relation to the sun. For instance, if you anaesthetise bees for a couple of hours, when they wake they don’t realise the sun has moved since they observed the dance, so they set off in what would have been the right direction, but arrive at the wrong location!
Fascinatingly, there are even regional dialect differences! For instance, French & Italian bees seem to misinterpret the distance when watching each others’ waggle dances.
But not everyone agreed…
The honey bee dance language debate was led by two scientists called Weiner & Wells between the late 1960s-early 1980s. They had a competing theory: odour finding, supported by experimental data.
Criticisms of the dance language included that:
- Stingless bees use buzzing runs to recruit other stingless bees to forage; are honey bees similarly just dancing to encourage other foragers to go out, after which they find the forage by scent?
- Why do only honey bees do these dances, when no other social insects do?
- Many recruits fail to find the forage and return empty-stomached, are they just generally searching in response to the dance? (Dan pointed out that the bees are observing the dance in the dark, within a busy, jostling environment full of thousands of other moving bees – no wonder they make a few errors!)
The debate led to experiments being repeated. The end result was that Von Frisch’s theory was generally agreed as correct, but how odour attracts foragers became more clearly understood.
The great honey bee researchers
Dan ran through some famous names who turn up time and again in the big honey bee dance language studies. In the 1980s-1990s the round dance was redefined by researchers including Kirchner, Lindauer & Michelsen as being effective from 1m upwards.
Martin Lindauer carried on Von Frisch’s research into honey bee behaviour. Lindauer then in turn developed a working relationship with Tom Seeley, who has now also become a renowned expert on honey bee behaviour.
In 1997 Jensen, Michelsen & Lindauer slowed down videos of honey bee round dance and showed a little waggle – there is a ‘waggle phase’ present in round dances.
And in 2008 the idea that there are different dances was challenged by Gardner, Seely & Calderone in the paper ‘Do honey bees have two discrete dances to advertise food sources?‘. They concluded that the round and waggle dance are really two ends of the same continuum, both containing information about distance and direction, with no clear switch between the two. They are just variants of the same recruitment dance.
In 2012, further experimental data was published by Griffin, Smith and Seeley: Do honeybees use the directional information in round dances to find nearby food sources? They verified Seeley’s earlier study with new experiments to show that the round dance communicates direction too. They used two feeders, one with a much stronger and therefore more appealing sugar syrup, placed at varying distances under 100m from the hive. They found that most of the bees went to the stronger syrup feeder after observing the round dance. Directional bias in recruitment was found for food sources as close as 5m from the hive.
Does all this matter? Maybe not, unless you are taking exams on honey bee behaviour! But still… I think it’s interesting to know. There is always more to find out about bees.
There was an interesting question from the audience: “Do bees communicate height in the waggle dance?” For instance, in a wood, would the dance communicate if the forage was up in the trees or down on the ground?
Don said he didn’t know! He thought von Frisch had done some experiments on this, but couldn’t remember their outcome. We also don’t know how bees communicate finding food above them in the hive, for instance when a feeder is put inside. This seems to lead to general robbing in the area.