First, the waggle dance of bees
In my last post on ant communication, I talked about how ants rely on the sense of touch and on chemical cues for much of their communication. And in the end I mentioned that I would talk about non-chemical methods of communication in the next post, which happens to be this one.
So I was going to talk about how ants also use sounds to talk to each other, and about how they sometimes do little dances to pass information. This bit about dancing made me a little nostalgic about the past, and I remembered, of all things, the Microsoft Encarta Encyclopedia. If you have never heard about this encyclopedia before, don't worry. This may be the last time you hear anyone talking about it. Microsoft discontinued this encyclopedia (that came in CD ROMs, by the way) in 2009 because of the "availability of free online references", but not to worry. You can still read about it in the Encyclopedia Britannica.
Anyway, I remembered it because I read about the waggle dance of bees, among many other things, in this encyclopedia for the first time.
Am I a robot?
Source: pixabay
The waggle dance is a dance of the honey bee in which a bee moves in a figure 8 pattern to signal the distance of a nectar source it has found. The signalling is done by the duration of the dance which signifies the distance of the nectar source, and by the angle of the dance which is encoded information about the angle at which the other bees need to fly relative to the sun in order to reach the source. The hive-mates get this information and fly to the precise location indicated by the dancing bee.
I thought that was pretty interesting.
Now the robotic bees
Then fast forward to 2011, and I read about some scientists in Germany who had built a robotic bee that could do the waggle dance and had succeeded in actually sending biological bees to… some place. The bees had got some information from the robotic bees and flew out of the hive, but they did not actually go to the place that the robots were signalling them about. So the robots were talking to the bees, just not very precisely.
You have to admit that it is a start.
You can read a news story about this research here, and if you would rather read a research article, you can read it here.
If you did not read any of those articles, one more thing you probably need to know about the robotic waggle is that scientists think the robots were lacking in two things: the leg moves and the chemicals. The mechanical bees did not possess legs for tap-dancing, unfortunately, and the lack of the natural pheromones could be an issue. The researchers do seem to have used sugar water to make it look like the robotic bee had just been to a nectar source and really knew what it was talking about, but the other bees were still getting the wrong signals.
You can watch a demonstration of the robotic bee doing the dance here.
So that is how you talk to bees.
Now the songs and dances of ants
Ants may look quiet to you, but they could be talking to each other all the time. It’s like when you are in a group of people from some country foreign to you and they talk in their language and you are left wondering. Except in this case of ants, you don’t even hear them talking because the sound is of extremely low intensity. In simple terms, the volume is too low. If you are really interested in hearing it, you might want to hold an ant near your ears when you see one next time because it is supposed to be audible when you do that. Don’t let it get into your ears, though.
Having insects crawl into my ears is a nightmare from my childhood, so I had to warn you about that.
So anyway, while not common to all species of ants, those that make a noise do it by rubbing an organ (a scraper, to be precise) near their petiole(the waist) against their abdomen. And the sound is primarily used for distress signals. In The Lives of Ants, the authors talk about leafcutter ants that use these sound signals to inform nest-mates about any new supply of leaves they find.
And then the authors go on to mention an interesting experiment in which scientists, again, talked to ants.
They placed two loudspeakers in two clumps of laurel leaves and mimicked the sounds that actual ants made when they found fresh, delicious leaves. They produced the sounds from only one speaker at a time. The ants flocked only towards the clump of leaves that had the loudspeaker making the noise. The clump with the silent loudspeaker was ignored.
So that is how you really talk to ants.
Now for the dances of ants
Ants are apparently not on a par with the bees when it comes to dances. However, communication using body movements and touches has been observed in some species including weaver ants. The movements are used to augment the communication that takes place primarily through pheromones.
Who's up for a little dance?
Source: pixabay
I cannot find any studies reporting robotic dancing ants.
On the other hand, simulated ants and robotic ants without dancing skills are quite abundant, but I will have to talk about them some other time.
A problem to think about
Now that we have talked so much about pheromones and their role in communication, here is a little problem to think about. If an ant gets off its pheromone trail by accident and then comes back to it and “forgets” which way it was going, how does it know which way to take? Right or left?
Among other things, I will talk about how ants use the position of stars for navigation in tricky situations in my next post. Let me know your thoughts on insect dances in the comments. Or about any dances you might be fond of. And don’t forget to let me know if you have used Encarta, too.
Links to references and image sources are in the text.