Risk taking behaviour predicts consistent and heritable coping styles in zebrafish

Coping styles are individually coherent sets of behavioural and physiological responses to stress. Coping styles are thought to remain consistent across context and time, and display a certain level of heritability. Here, we examined whether risk taking is a predictor for consistency and heritability of stress coping styles in both larval and adult zebrafish (Danio rerio).

A group emergence test where fish emerge from a familiar housing compartment into a potentially dangerous novel environment, established the level of risk taking of F0 generation adult zebrafish. The degree of risk taking appeared to be consistent over time and context. Then, the F0 risk taking degree was further correlated with various behavioural parameters related to stress coping of the F1 and F2 generations. In larval fish, these parameters were measured during a light dark challenge which elicits an anxiety like response. In adults, they were measured during a single emergence test and a combined open field and mirror biting test, estimating the degree of risk taking and the level of explorativeness and aggressiveness. The results show that (i) parental risk taking behaviour is a good predictor for a large number of larval and adult behavioural parameters, within and between generations; (ii) a number of these parameters are consistent over ontogenetic (larval and adult) stages within the same generation, and (iii) four of these parameters representing risk taking, aggressiveness, and swimming behaviour, were correlated over multiple generations, establishing heritability of coping styles.

We conclude that risk taking behaviour is a strong predictor of coping style within and between generations and behavioural parameters associated with risk taking are consistent over time and heritable over generations.