January 30, 2009
Fish Study Shows Boldness Is Dependant On Partner
According to a British study published on Thursday, stickleback fish are more willing to take risks when in pairs.
Although the stickleback fish tends to find protection in numbers, researchers also discovered the leading fish would become proportionally bolder depending on the shyness of the following fish.
"Our study shows that the process by which leaders and followers emerge is a dynamic one," said Andrea Manica of the University of Cambridge.
"Individuals aren't simply born leaders or followers, but their role in a pair -- and, we could speculate, in a larger group -- is the result of social feedback where everyone plays a role."
The researchers were able to distinguish the bold fish from the shy by studying which fish were more likely to leave their weeds to search for food in the shallow part of the tank.
Then the scientists removed a partition so the fish could see their neighbors. At that point the researchers noted how many times the fish would leave the weeds, and in what order they would leave.
The fish made synchronized trips to the shallow end of the tank in search of food, with the bold fish leading a majority of the time.
The study, which appeared in the journal Current Biology, noted that bold fish paired with the shiest mates were far more likely to leave the weeds in search of food. The bold fish would often stay in the open after the shy fish returned to safety.
According to the researchers, leadership in the stickleback fish stemmed from the differences in the way individual fish reacted to their partner's actions.
"If a shy individual is paired with a very bold individual, the latter 'inspires' the former into becoming a very faithful follower," Manica told Yahoo News.
"Conversely, a very shy individual seems to bring out the leadership of the bolder companion, which becomes a much stronger leader than if it was paired with a less shy companion."
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