German scientists have shown, that by selective breeding of zebrafish, distinct personality traits occur both in behaviour and also brain activity.
The researchers, from EARA Member the Max Planck Institute of Neurobiology, Germany, put zebrafish into two groups based on their response to a loud sound, the ‘relaxed’ group then learned to ignore it quickly, while the ‘skittish’ group did not.
Breeding the fish within their respective groups, they then found that within two generations the offspring of the two groups differed significantly in the brain activity that is associated with personality differences and psychiatric conditions in humans.
"The pace at which personality traits can be shifted and fixed in evolution is remarkable" says Herwig Baier, co-author of the study.