In movies, robots often inspire fear. And, in the lab, they can be used to frighten live animals to test behavioral changes. Scientists at NYU-Poly are using robots in order to test how the presence of alcohol affects the behavior of zebrafish. As zebrafish have similar emotional responses to stimuli as more intelligent animals, scientists can test how certain elements in an environment can cause certain behaviors.
Fish have previously shown that they are attracted to robots that are designed to look, act, and swim like them, so the scientists decided that they would be good candidates for this new study. The purpose of the experiment was to determine how fear is affected by the presence of ethanol, which is the type of alcohol found in most alcoholic beverages that humans drink, as well as in fuel and solvents. Instead of creating robots that the fish would relate to, though, the scientists created a robot that resembled a predator of the zebrafish: the Indian leaf fish. In an aquarium with three compartments, the scientists placed zebrafish in one compartment, the robot in a second, and left the third compartment empty. As expected, the fish in this control group naturally did what they could to avoid the fake predator and seemed to prefer the empty part of the aquarium.
After recording their findings, the scientists took separate groups of zebrafish and added ethanol to their water (don't worry, it doesn't cause any lasting damage to the fish). To continue to test their theory, the scientists then put a group of zebrafish into a tank with two compartments: one with good lighting and one that was dark. In a different tank, the scientists created a mock heron attack from above the water. As expected, the group of zebrafish not exposed to ethanol avoided the dark and swam away from the mock heron attack. However, the fish exposed to ethanol seemed to prefer the dark and had a slower response to the attack.
While it doesn't seem necessary to frighten fish to discover that alcohol affects behavior in such a way, scientists believe that these findings, along with the use of robots in such studies, can be used to better understand animal behavior, as well as aid in animal protection.