Predator‐induced Plasticity

Abstract

Abstract Predator‐induced plasticity is an important mechanism enabling prey survival in complex environments. Prey alter a diversity of traits including behaviour, morphology and life history in response to predators to reduce their risk of predation. However, predator‐induced plasticity has associated costs including reduced competitive ability. To maximise fitness, prey modulate their phenotypic responses to the level of predation risk in the environment. Prey detect differences in predator densities or predators consuming more prey and track temporal variation in predation risk. Prey also detect different predator species in the environment and form predator‐specific defences. In aquatic systems, prey possess sophisticated sensory systems that enable the detection of chemical cues released by damaged prey and predators. Predator‐induced plasticity also influences interactions within larger communities and can lead to trophic cascades. Key Concepts: Phenotypic plasticity is one mechanism organisms use to cope with environmental heterogeneity. Environmental heterogeneity in predation risk favours the evolution of predator‐induced plasticity in a diversity of prey species. Prey that express predator‐induced plasticity in behavioural, morphological and life history traits can reduce their likelihood of predation, but the responses have associated costs. To maximise fitness, prey fine‐tune their defences based on predator species identity, predator density, amount of prey consumed by predators and the prey species being consumed. The expression of predator‐induced plasticity can impact species interactions throughout food webs.