A large portion of what animals do is interact with each other. As a social species, we can hardly go an hour without some kind of interaction with another human, be it face-to-face or via text or email. Even animals that aren’t particularly social still generally have to interact with each other once in a while, at the very least to mate.

Scientists who study animal behaviour will often look at social interactions, like males competing with each other, males courting females or juveniles playing with each other. If a scientist wants to address a particular behaviour, often it can be difficult to wait in the animal’s natural environment to see it occur spontaneously. Instead, the scientist might try to induce the behaviour by designing an experiment that specifically looks at the behaviour in question. For example, if you want to see what a male cricket does when he wins a fight, you stick him in a fighting arena with another male cricket. Similarly, if you want to see how ants coordinate moving large objects together, you give them a big object to move and watch what they do. However, what if you want to see what an animal does in response to a very specific behaviour of another animal?

For example, if you want to see what a dog does when it sees a cat hissing and arching it’s back, what could you do? Well, the most obvious thing to do would be to put a cat in front of it. However, what if the cat happened to love dogs, and instead went up and tried to make friends with the dog; it would be a waste of the scientist’s time. Another problem could be that different cats behave differently with different dogs: some would arch their backs but not hiss, some would hiss but not arch their backs, some would meow, and it would be really difficult to differentiate between which of these cat behaviours was making the dog behave a particular way.

Another way to test a dog’s response to a specific cat behaviour would be to film a cat or a few cats behaving the way you wanted, and then show the video to dogs to see how they respond. A protocol like this was recently used in an experiment with primates that I wrote about here. However, this method also has it’s limitations. Not all animals are as visual as us, for example dogs may pay a lot more attention to the smell a cat gives off than the visual cues. Also, other animals’ vision differs from our own, and even if a video screen looks the same as real life to us, it might look completely different to another animal who’s visual system is very different.

One additional way that we might be able to create a situation to look at an animal’s behaviour in a controlled setting would be to use a robot. Did I just say robot? Yes, robot. For example, robofish has been used in studies on group behaviour and shoaling, with the other fish generally following or being guided by robofish.

A recent study used a robot to look at chimpanzee behaviour. This robot was a doll that had been wired up so that it could move its head 45 degrees to the left and right (sadly not 360 degrees, as I suppose the scientists didn’t want to see what reaction this would induce in the chimps) and move it’s arms and legs independently. The doll also had a loudspeaker fitted into its chest through which sounds could be played. All I can say is that I’m glad I wasn’t the one in the room with this robodoll.

It seems that some of the chimpanzees were as freaked out by the robodoll as I would be, with 14 of 16 of them demonstrating ‘aversive behaviours’ including smashing boxes against the wall and having their hair stand on end. However, within the first minute, nine of these subjects calmed down and were tested by the researchers.

First the chimpanzees watched a human that they knew interact with the robodoll. The idea of this was to show the chimps that the robot could interact, and to try to encourage them to interact with it too.

The researchers then got the robodoll to either imitate the chimpanzee being tested (by moving its head, arm and legs in the same way as the chimp was doing), or perform random movements, to see how the chimp would react. The researchers also had the robodoll either laugh or scream at the chimpanzees, to see what effect this would have.

Amazingly, once the chimpanzees calmed down, they interacted with the robodoll a fair bit, especially when the robodoll was imitating them (rather than doing random body movements). The chimps were actually very nice to the robodoll: they invited the doll to play with them, offered it toys, reached out with their hands towards the doll, or banged themselves against other objects. This last behaviour apparently did not seem to be a fearful or aggressive behaviour, but more likely at attempt to get the robodoll’s attention. One chimpanzee even laughed at the robot while trying to play with it. However, the chimps generally didn’t respond to the robodoll laughing, maybe this was just a bit too Chucky doll-like. It’s worth mentioning that the researchers used human laughter rather than chimpanzee laughter, and using the latter would have been more likely to evoke a response in the chimps.

This research shows that chimps will respond to simple gestures from a robot. While this experiment is fun, it also shows how a robot could be used to study communication and behaviour in this animal in a carefully controlled way.





Photo Credits

People on phones: David Roseborough

Dog and Cat: Peretz Partensky

Robofish: Robofish research page

Robodoll: taken from Davila-Ross et al. (2014)

First Chimpanzee: Junk Food Monkey

Chucky doll: Chuckywiki

Second chimpanzee: William Warby



Davila-Ross, M., Hutchinson, J., Russell, J. L., Schaeffer, J., Billard, A., Hopkins, W. D., & Bard, K. A. (2013). Triggering social interactions: chimpanzees respond to imitation by a humanoid robot and request responses from it, 17: 589–595. DOI: 10.1007/s10071-013-0689-9