Size-selective harvesting fosters adaptations in mating behavior and reproductive allocation, affecting sexual selection in fish

1. The role of sexual selection in the context of harvest-induced evolution is poorly understood. However, elevated and trait-selective harvesting of wild populations may change sexually-selected traits, which in turn can affect mate choice and reproduction.
2. We experimentally evaluated the potential for fisheries-induced evolution of mating behavior and reproductive allocation in fish.
3. We used a unique experimental system of zebrafish (Danio rerio) lines exposed to large, small, or random (i.e. control) size-selective mortality. The large-harvested line represented a treatment simulating the typical case in fisheries where the largest individuals are preferentially harvested. We used a full factorial design of spawning trials with size-matched individuals to control for the systematic impact of body size during reproduction, thereby singling out possible changes in mating behaviour and reproductive allocation.
4. Both small and large size-selective mortality left a legacy on ma...