It's Dr. Seuss meets science: Israeli researchers have taught six goldfish how to "drive," or, more specifically, direct their tanks-on-wheels in a deliberate manner. In a study published in Behavioural Brain Research, scientists at Ben-Gurion University of the Negev write that "navigation is a critical ability for animal survival," but it's not fully clear whether the mechanisms behind it are dependent on the species or ecological system, or on something more universal. One way to explore that question is through "domain transfer methodology," where you essentially put one species into another species' environment—hence, goldfish landed in a wheeled terrestrial platform dubbed a Fish Operated Vehicle (FOV).
NPR reports the tank was equipped with "an intricate camera system" that captured the fish's movement characteristics, location, and orientation in the tank and converted it into navigational directions. As to what the fish (named after Pride and Prejudice characters, per the Guardian) were supposed to navigate to, a press release explains that researchers put a "clearly visible target" on a wall directly in front of the tank. After a few days of training that involved giving the fish food pellets when they drove to the pink target, the fish managed to direct the FOV to the target. That was true even in cases where they hit a wall along the way or started from a new point; they also weren't sidetracked by decoy targets. (See video here.)
The takeaway? "The study hints that navigational ability is universal rather than specific to the environment," says Shachar Givon, a PhD student in the Department of Life Sciences in the Faculty of Natural Sciences. "Second, it shows that goldfish have the cognitive ability to learn a complex task in an environment completely unlike the one they evolved in." Adds Givon, per NPR: "Since on the evolutionary scale our common ancestor is very, very far back, finding that fish share navigational skills similar to our own really speaks volumes to the importance of these skills in the animal kingdom." (Read more discoveries stories.)