Within many species of animals, people display different personalities. For example, some people are consistently more bold than others.
"But in biology, we still do not fully understand what's behind the fact that humans or animals have different personalities." In humans, people with different levels of signaling substances in the brain, like serotonin or dopamine, behave differently. But we do not know if differences in these signaling substances can explain differences in personality in other species and whether signaling substances cause observed differences or differences in behavior and levels of signal substances depend on another underlying factor, says Robin Abbey-Lee, postdoctoral at the Faculty of Physics, Chemistry and Biology of IFM, one of the scientists who led the study.
Drugs for crickets were thrown to people
Researchers therefore wanted to actively change levels of serotonin and dopamine signals to investigate and use crickets for research. They did this by giving crickets that affect serotonin and dopamine systems and used to treat depression or Parkinson's disease. Because the serotonin and dopamine systems of different animals are similar, scientists expected drugs to affect crickets as well.
"In this study, we wanted to achieve a significant knowledge gap by experimentally altering the levels of these signal substances and see if this could change the behavior in the cysts," says Hanne Løvlie, assistant professor at IFM, who studied the study.
Then he measured the behavior of the cricket
The researchers measured three different behaviors in cysts.
"We measured how active crickets were in a familiar environment, which corresponds to how much a person moves in his or her own home." We also investigated cricket behavior in a new environment, as did the behavior of a person during a visit to a new city. the way crickets behave in a fight situation to measure the aggressiveness of individuals – says Robin Abbey-Lee.
Researchers have found that changing serotonin levels makes crickets less active and less aggressive. On the other hand, the changed levels of dopamine were not associated with changes in cyst behavior.
'This suggests that serotonin plays a more prominent role in these behaviors,' says Hanne Løvlie.
Discoveries increase our understanding of why animals have personality. They also raise the question of how drugs that get into nature through our sewage affect wild animals.
"Experimental manipulation of monoamine levels changes personality in crickets", Abbey-Lee RN, Uhrig EJ, Garnham L, Lundgren K, Child S, LøvlieH, (2018), scientific reports published on November 1, 2018.