BRISTOL, England – Despite their small size, ants have big-brained methods for learning new skills and trades. Scientists from the University of Bristol used a small robot to blend in with rock ants and uncover their secrets of teaching each other complex behavior such as directions to a new area.
The key behind teaching ants another route is through tandem running. The instructor will poke and prod another ant as signals that they’re in the right direction or need to reorient themselves. Once the student learns the new route and can find its way back home, it becomes the teacher. They then lead another ant and the cycle repeats.
“Teaching is so important in our own lives that we spend a great deal of time either instructing others or being taught ourselves. This should cause us to wonder whether teaching actually occurs among non-human animals,” says Nigel Franks, a professor of Bristol’s School of Biological Sciences in a statement. “And, in fact, the first case in which teaching was demonstrated rigorously in any other animal was in an ant.”
The team built a robot that could substitute as the teacher ant. If the other ants were able to follow the robot’s approach then it would indicate that the team knew all the elements for ant teaching.
After building the robot, the researchers created a large arena to put distance between the old, low-quality nest and a newer one that could be led to by a robot. Scientists were able to move the robot around in wavy and straight approaches using a sliding overhead bridge, called a gantry, attached to it. The robot came equipped with attractive scent glands from a worker ant, to mimic the pheromones of an ant teacher.
“We waited for an ant to leave the old nest and put the robot pin, adorned with attractive pheromones, directly ahead of it,” explains Franks. “The pinhead was programmed to move towards the new nest either on a straight path or on a beautifully sinuous one. We had to allow for the robot to be interrupted in its journey, by us, so that we could wait for the following ant to catch up after it had looked around to learn landmarks.”
The gantry had another purpose: tracking the path of the returning ant and whether it followed the instruction of the robotic teacher. The researchers found the robot was successful in teaching the student ant how to get back to the old nest, regardless if the route was curvy or direct.
“A straight path might be quicker but a winding path would provide more time in which the following ant could better learn landmarks so that it could find its way home as efficiently as if it had been on a straight path,” adds Franks. Not only did the robots teach other ants how to get home, but those that were taught by it versus not taught were more successful and quicker in their return trip.
The study is published in the Journal of Experimental Biology.