A team of researchers from Exeter University has discovered that fish have different personalities and unique traits, a new study published in Functional Ecology reports.
Researchers tested this idea by putting different threats — such as models of herons — around the tanks of Trinidadian guppies and seeing how they reacted.
While the team expected the fish to follow a “simple spectrum” where they all reacted to potentials dangers in the same way, the scientists found this not to be the case. Rather, some guppies were braver than others.
“The idea of a simple spectrum is often put forward to explain the behavior of individuals in species such as the Trinidadian guppy,” said lead author Tom Houslay, a researcher at Exeter University, according to The Independent. “But our research shows that the reality is much more complex.”
The team found that when guppies are put into a strange environment they have different coping strategies. Some hide, some attempt to flee, while others cautiously explore the area. These differences were consistent over multiple tests and held true in a range of situations. Even though some fish changed their reactions based on the threat, the relative differences between each individual stayed the same.
That behavior suggests each fish is different. The team plans to expand on their new research to see how this information could be used to expand their knowledge of fish populations.
“We are interested in why these various personalities exist, and the next phase of our research will look at the genetics underlying personality and associated traits,” said study co-author Alastair Wilson, a professor at the University of Exeter, according to The Guardian. “We want to know how personality relates to other facets of life, and to what extent this is driven by genetic, rather than environmental, influences. The goal is really gaining insight into evolutionary processes, how different behavioural strategies might persist as species evolve.”