Why do prawns have different personalities ?

Prawns have personalities—and cautious crustaceans do better in the battle for food, new research shows. Scientists from the University of Exeter studied rockpool prawns (Palaemon elegans) and found some were consistently shy, while others were bolder. But this bravery may come at a cost—as the risk takers tended to do worse than other prawns when competing for food.

"We found that the shyer prawns were better at controlling a food source," said first author Daniel Maskrey, formerly of the University of Exeter but now at the University of Liverpool. "This means that when they found food and possible rivals were nearby, they stayed and fed for longer than bolder prawns. "The reasons for this aren't clear, but it's possible that bolder prawns have a higher urge to go on and continue exploring."

"Some individuals are more successful at monopolising food, while others are more willing to engage in potentially risky exploration," he said. "In different conditions and situations, either of these strategies might pay off—which might explain why evolution has not led to a single personality type. "The rockpools where these prawns live change with each high tide, and having such variation among prawns could be crucial when it comes to adapting to these and other changes."
https://phys.org/news/2018-06-cautious-prawns-food.html