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Abstract Landscapes of fear can determine the dynamics of entire ecosystems. In response to perceived predation risk, prey can show physiological, behavioral, or morphological trait changes to avoid predation. This in turn can indirectly affect other species by modifying species interactions (e.g., altered feeding), with knock‐on effects, such as trophic cascades, on the wider ecosystem. While such indirect effects stemming from the fear of predation have received extensive attention for herbivore–plant and predator–prey interactions, much less is known about how they alter parasite–host interactions and wildlife diseases. In this synthesis, we present a conceptual framework for how predation risk—as perceived by organisms that serve as hosts—can affect parasite–host interactions, with implications for infectious disease dynamics. By basing our approach on recent conceptual advances with respect to predation risk effects, we aim to expand this general framework to include parasite–host interactions and diseases. We further identify pathways through which parasite–host interactions can be affected, for example, through altered parasite avoidance behavior or tolerance of hosts to infections, and discuss the wider relevance of predation risk for parasite and host populations, including heuristic projections to population‐level dynamics. Finally, we highlight the current unknowns, specifically the quantitative links from individual‐level processes to population dynamics and community structure, and emphasize approaches to address these knowledge gaps.
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Ecosystem Effects of Predators Are Amplified Across Generations Through Prey Behavioural Plasticity
ABSTRACT Predator‐induced changes in prey traits can cascade through ecosystems to impact biogeochemical cycling and community structure. Whether these effects persist, amplify or diminish across prey generations remains uncertain. We tested for predator transgenerational effects using a 3‐year common garden experiment in a terrestrial old‐field ecosystem. Predator exposure was manipulated across two generations of four grasshopper herbivore prey populations, with measurements of ecosystem processes made alongside measurements of prey trait responses. We found predators had larger effects on plant community biomass, plant diversity and soil carbon accumulation in the second generation of predator exposure than in the first generation. Paired with trait data on the grasshoppers, we found this amplification of ecosystem effects corresponded with heightened antipredator behaviours in the second generation. Our results show that transgenerational behavioural plasticity can magnify predator‐driven ecosystem impacts across generations, linking eco‐evolutionary processes with ecosystem dynamics.
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- Award ID(s):
- 2011884
- PAR ID:
- 10647903
- Publisher / Repository:
- John Wiley Publishing
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 28
- Issue:
- 11
- ISSN:
- 1461-023X
- Subject(s) / Keyword(s):
- biogeochemistry | eco-evolutionary feedbacks | functional traits | nutrient cycling | predator–prey interactions | trait-mediated effects | transgenerational plasticity | trophic cascades
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/ele.70246
