Chris - And this is one ant showing another ant how to go somewhere to find food or something.
Nigel - That's exactly it. But what's really interesting about it is that it's a very slow process. What we see is that the follower stops periodically, and to all intents and purposes we're sure that's it's looking round for landmarks to learn. Only when it's learnt a landmark does it signal to the leader that the lesson can continue.
Chris - How do they actually tell each other that they're doing it right? How is the information passed between the teacher and the pupil?
Nigel - It's a very interesting thing, and what happens is an absolutely gorgeous bit of behaviour. The follower taps on the hind legs and abdomen of the leader, and only when the leader is very frequently tapped by the antennae of the follower, does the leader proceed. What you can do is take the follower away and use a hair to tap on the leader. If you tap very frequently, she'll keep running. In other words, it's a signal from the pupil that says that they've learnt this part of the path and now they can proceed.
Chris - Now in medicine we have this motto where you see one, do one, teach one, and you might apply that to an operation for example. Does the same thing happen in ants?
Nigel - I think it does, because once the follower has got to the food and knows where it is, will actually return to the nest and very frequently begin to teach somebody else. So even though tandem running is rather slow and ponderous, the beauty of it is that the pupil can, in turn, become a teacher and so the information can flow through the society.