Fish Learn to Drive a Fish-Mobile to Navigate Dry Land
An ingenious study shows fishes can transfer water-based navigational skills.
Posted January 13, 2022 | Reviewed by Lybi Ma
Fishes are amazing beings. During the past decade, research has shown that they are smart, sentient, and emotional animals who are quite capable of learning to solve complex problems and displaying care and compassion.1 Here is an ingenious study that shows how fishes can learn to drive an aquatic car in their tank and negotiate terrestrial environments. The research I'm writing about can be found in a paper by Shachar Givon and colleagues published in Behavioural Brain Research called "From fish out of water to new insights on navigation mechanisms in animals."2 A short review can be seen here along with a video of the fish-mobile.3
Playing off the facts the fishes can learn to navigate a wide variety of environments and that the neural basis of goldfish navigation is similar to that found in the hippocampal formation of mammals and birds, the researchers built a water-based Fish Operated Vehicle (FOV), "a wheeled terrestrial platform that reacts to the fish’s movement characteristics, location and orientation in its water tank to change the vehicle’s; i.e., the water tank’s, position in the arena." (See Figure 1 in their study.) They used what's called domain transfer methodology by asking six goldfishes to navigate an alien environment they could see through the walls of the tank. The researchers write: "The fish's control of the vehicle was enabled by streaming the video signal from the camera to the computer which performed segmentation and detection to find the fish's location and orientation in the water tank." (Figure 1B in their study.)
The results of this clever study can be summarized as follows.
Fishes became more proficient with increasing practice. (See Figure 4 in their study.)
Fishes were able to adjust their strategy to correct for unsuccessful initial attempts.
As the fishes were challenged by changes from where they began driving and alterations in the initial terrestrial environment, they learned to navigate novelty and avoid dead-ends.
The importance of comparative research
This sort of research is needed to learn about the cognitive skills and behavioral plasticity of other animals who live in vastly different ecosystems from those in which we and other well-studied animals live. It opens the door for further comparative research on animals who live in alien environments to see if they, too, are able to transfer their navigational skills to situations to which they have never been exposed.
We also will learn a lot about the evolution of different navigational skills (and other behavior patterns) and if there are any shared cross-species solutions to the problems with which diverse species of animals are confronted. These data also will shed light on the evolution of unique solutions to common problems that animals face in their daily activities in the habitats in which they evolved and in which they currently live.
1) For discussions of the science and many references showing fishes have rich and deep cognitive and emotional lives, click here.
2) The abstract that includes a summary of the methods reads: Navigation is a critical ability for animal survival and is important for food foraging, finding shelter, seeking mates, and a variety of other behaviors. Given their fundamental role and universal function in the animal kingdom, it makes sense to explore whether space representation and navigation mechanisms are dependent on the species, ecological system, brain structures, or whether they share general and universal properties. One way to explore this issue behaviorally is by domain transfer methodology, where one species is embedded in another species’ environment and must cope with an otherwise familiar (in our case, navigation) task. Here we push this idea to the limit by studying the navigation ability of a fish in a terrestrial environment. For this purpose, we trained goldfish to use a Fish Operated Vehicle (FOV), a wheeled terrestrial platform that reacts to the fish’s movement characteristics, location, and orientation in its water tank to change the vehicle’s; i.e., the water tank’s, position in the arena. The fish were tasked to “drive” the FOV towards a visual target in the terrestrial environment, which was observable through the walls of the tank, and indeed 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. These results demonstrate how a fish was able to transfer its space representation and navigation skills to a wholly different terrestrial environment, thus supporting the hypothesis that the former possess a universal quality that is species-independent.
3) Popular accounts of this research can be seen here.