Integrative and genomics approaches to uncover the mechanistic bases of fish behavior and its diversity

Understanding the molecular mechanisms underlying fish behavior is of fundamental importance to further our understanding of the proximate and ultimate causes of variation in this trait and informs us on issues of animal husbandry, conservation, and welfare. One way to approach this question is to study variation in gene expression in individuals exhibiting different behaviors and relating it to variations at other phenotypic levels in an organismic, ecological and evolutionary context. Here we review studies that have shown that the use of such an integrative and genomics approach is greatly useful for shedding new light on the mechanisms of behaviors as diverse as social dominance, mate choice, reproduction and migration. We present studies that use functional genomics tools and integrate several biological levels of organization, including transcription variation, which are important in the context of integrative biology and genomics of fish behavior. We review studies of phenotype-level variation in transcription but also studies that focus on variation at the individual-level. Dissecting the molecular bases of among-individual variation in behavior, including the study of variation in temperament (behavioral syndrome / coping style) within and among populations, will gain importance in the field in the years to come.