The specificity of sperm-mediated paternal effects in threespined sticklebacks

Abstract

Parental effects can help offspring cope with challenging environments, but whether these effects are unique to specific environmental conditions is largely unknown. Parental effects may evolve via a core pathway that generally prepares offspring for risky environments or could be stimuli-specific, with offspring developing phenotypes that are tailored to specific environmental challenges. We exposed threespined sticklebacks (Gasterosteus aculeatus) fathers to a potentially threatening stimulus (net) versus native predator (sculpin). Offspring of sculpin-exposed fathers were more responsive (greater change in activity) to a simulated predator attack, while offspring of net-exposed fathers were less responsive (lower plasma cortisol and fewer antipredator behaviors). To evaluate offspring response to native and non-native stimuli, we sequentially exposed offspring of net-exposed, sculpin-exposed or control fathers to a net, native sculpin model, or non-native trout model. Paternal treatment did not influence offspring response to stimuli; instead, offspring were more responsive to the native sculpin predator compared to nets or non-native trout predator. Collectively, we demonstrate that sperm-mediated paternal effects in response to different, potentially stressful stimuli result in distinct offspring phenotypes. This specificity may be key to understanding the evolution of adaptive parental effects and how parents prime offspring for encountering both evolved and novel environmental stimuli.Competing Interest StatementThe authors have declared no competing interest.View Full Text