The zebrafish is a freshwater fish in the order Cypriniformes that belongs to the minnow family. It is a popular aquarium fish native to South Asia. It is often sold under the trade name zebra danio and is referred to as a tropical fish. They can be commonly found in private ponds. These fishes are vital and widely used in scientific research, such as drug development, particularly pre-clinical development. They are also notable for their regenerative abilities, and researchers have modified them to produce numerous transgenic strains. One fascinating behavior of Zebrafish is when they get drunk they are able to assume the role of a leader. Let’s find out how.
If you put a drunk zebrafish in a tank with sober zebrafish, the sober ones will follow the drunk fish around the tank as their leader. Apparently, the sober ones saw leadership qualities in the drunk zebrafish.
What Happens if the Zebrafish Becomes Inebriated?
Previous research found that a moderate amount of alcohol makes fish more active, while a higher amount slows them down. However, for this study, they wanted to see how an alcohol-exposed fish would behave in the presence of sober fish.
After soaking each zebrafish in a beaker of water and ethanol for a few minutes, they placed it in a tank with four sober zebrafish and watched them interact for five minutes. A camera from above captured the group so that the scientists could use a tracking algorithm they’d recently developed to measure the fishes’ movements.
The alcohol-exposed fish swam faster as a group than as individuals. This could be because moderate intoxication causes them to become hyperactive, as previous research has shown; they may overreact to the stimulus of seeing other fish nearby. Moderate amounts of alcohol have also been shown to lower fish inhibitions, making zebrafish more aggressive and less afraid of new experiences.
Meanwhile, the four sober fish did not ignore their inebriated counterpart as they zipped around the tank: they pursued it. There are several possible explanations for this. Perhaps something about the drunk fish’s one-on-one interactions with the other fish influenced the entire group to move in the same direction.
Perhaps the sober fish saw a leader in their non-sober tankmate. The sober fish sped up to keep up with the drunk fish, swimming roughly a third faster than they would have otherwise.
The drunk fish’s uninhibited behavior is most likely perceived as a boldness trait, conferring a high social status.
Maurizio Porfiri, Aquatic Researcher
(Source: Discover Magazine)
Do Zebrafish Get Hangovers?
In terms of development, behavior, and genetics, zebrafish appear to be very similar to humans, with another study finding that when their eggs are exposed to alcohol, the fish grow up to be more anti-social, an insight that could help with understanding how mothers’ alcohol consumption affects unborn babies.
The scientists were unable to determine whether zebrafish experience hangovers, but they did note that they return to normalcy after a day or so. (Source: Independent)