You can take a fish out of water, but can you teach it to drive? It might sound like the stuff of fairy tales — or fish tales, rather — but Israeli researchers have been able to train a goldfish to steer a vehicle.
Scientists at the Ben-Gurion University of the Negev (BGU) in Beersheba say they have trained a goldfish to operate a “Fish Operated Vehicle” (FOV). More specifically, they have taught the goldfish how to direct this vehicle in the direction that it wants to swim.
The researchers wanted to test whether an animal has innate navigational abilities or if an animal is restricted to its home environments, according to a statement from BGU.
They designed a set of wheels under a goldfish tank with a camera system to record and translate the fish’s movements in different directions to the wheels.
Six goldfish were taught to navigate the vehicle, earning a reward when each one found its way around a small room. According to the study, the reward was a small food pellet, identical to fish food.
The study was conducted by Shachar Givon, a PhD student in the Life Sciences Department in the Faculty of Natural Sciences, Matan Samina, an MSc student in the Biomedical Engineering Department in the Faculty of Engineering Sciences, Prof. Ohad Ben Shahar of the Computer Sciences Department and head of the School of Brain Sciences and Cognition, and Prof. Ronen Segev of the Life Sciences & Biomedical Engineering Departments.
It was published in the peer-reviewed scientific journal Behavioural Brain Research.
According to the study, the results showed that the fish “were able to operate the vehicle, explore the new environment, and reach the target, regardless of the starting point, all while avoiding dead-ends and correcting location inaccuracies,” Givon said.
The researchers trained a fish to steer a FOV, which was made up of a chassis that housed a platform with a water tank on it. Underneath the platform, four engines connected to four omni wheels were mounted on four sides of the metal skeleton. A Perspex water tank was placed on that platform so that the water reached 15cm. The water level was relatively low to reduce surface waves while the FOV was moving.
They tested whether the fish was really navigating, by placing a visible target on the wall opposite the tank. After a few days of training, the fish was required to navigate to the target. The computer system followed the fish’s movement towards the walls of the tank, which moved the vehicle in that direction.
The researchers challenged the fish with several control sessions where they manipulated the environmental settings to explore different skills or strategies, in order to further explore fish navigational skills.
Many of the fish went from needing 30 minutes to find the target, to finding it in under a minute.
They found that “a goldfish’s navigational ability supersedes its water environs,” according to BGU. The fish were not only able to navigate to the target but could even continue doing so when interrupted in the middle (by hitting a wall, for example). They were not fooled by false targets placed by the researchers.
The study also “hints that navigational ability is universal rather than specific to the environment,” Givon explained, “Second, it shows that goldfish have the cognitive ability to learn a complex task in an environment completely unlike the one they evolved in. As anyone who has tried to learn how to ride a bike or to drive a car knows, it is challenging at first.”
The fish “were able to operate the vehicle, explore the new environment, and reach the target regardless of the starting point, all while avoiding dead-ends and correcting location inaccuracies,” the researchers said in the study, “These results demonstrate how a fish was able to transfer its space representation and navigation skills to a wholly different terrestrial environment.”
