Behavioural syndromes are important in the context of understanding the evolution of behaviour. This study examines the lifetime development of shy/bold behaviour of dumpling squid (Euprymna tasmanica). The first component examined correlations of shy/bold behaviour across two test contexts - a threat and a feeding test, measured 5 times during the lifetime of the squid. The second component examined developmental plasticity in shy/bold phenotypes with age and sexual maturity.

This study used crosses of wild-caught dumpling squid (Euprymna tasmanica) males to multiple females with known behavioural types to evaluate patterns of additive and residual variance in behavioural traits from offspring under two contexts - a threat and a foraging test. Genetic contributions to behavioural expression were context-dependent. Threat context behaviour had significant heritability, while foraging context behaviour had lesser additive and greater residual components. Female trait variation was not correlated with fecundity. Female foraging boldness (which co-varied with size) explained some variation in brood hatching success. Positive assortion of mate pairs according to shy-bold phenotype determined fertilization success.