Researchers were able to cause fear in fish using a robotic predator. Source: NYU/ Simone Macri
NYU engineers have developed a robotic predator so realistic that it causes fear among real fish. The study has significant implications for scientific research involving animals.
The predator at hand is a red tiger oscar fish. It might seem small, but not in the eyes of a zebrafish. The latter is often used in behavioural studies thanks to its versatility. However, there are a number of issues with using live animals to conduct research, mainly their unpredictable nature. That’s one of the reasons Maurizio Porfiri, an NYU professor of mechanical and aerospace engineering, creates bio-inspired robots.
He says there are a number of advantages to using robots in animal behavior studies, including consistency and repeatability (the researchers are able to control their robotic predator as opposed to relying on a live one).
Robotic models vs real oscar fish
Porfiri and his team divided an experimental tank into three compartments; one was empty, the second contained live zebrafish and the final one featured three different experimental stimuli. The zebrafish exposed to real oscar fish and those that spent time with the robotic models exhibited similar behavior. In fact, the fish tended to avoid the robot more than the real oscar fish.
“Avoidance isn’t the only way we can tell a zebrafish is scared,” Porfiri told NYU. “When these fish are afraid, they also swim differently, and we were surprised to find that the robotic fish could produce an even stronger fear-related response than the actual live predator.”
Choosing the right predator
In contrast, the zebrafish exhibited little fear towards animated images of the predator. “The oscar fish is a known zebrafish predator, but it’s not the most threatening one out there,” said Porfiri. “We chose a predator that could be relied upon to scare the zebrafish, but not to the point of complete avoidance that would mask what we were trying to uncover.”The study proved to the team that it’s possible to induce fear in an animal using a robot. Their findings will be released in the June issue of the Zebrafish journal.
Source: NYU