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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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Increases in predation favour evolutionary shifts in behavioural plasticity in Trinidadian killifish (Anablepsoides hartii)
Abstract Behavioural plasticity is expected to be favoured in risky environments, such as when prey species coexist with predators because prey must alternate between fitness-related foraging/mating behaviours and antipredator behaviours that enhance survival. We compared behavioural plasticity in Trinidadian killifish that are found in sites with and without predators. We quantified aggressive and antipredator behaviours via a mirror assay in second-generation lab-reared and wild-caught killifish before and after exposure to predator cues. We compared 2 types of aggression including: overt aggression (ramming, biting, lunging, and tail-slapping) and display aggression (spine arching, bending into an s-shape, and opercular flaring). We additionally compared the amount of time the fish spent frozen as a proxy for antipredator behaviour. We show clear differences in plasticity between populations with and without predators. Killifish from sites with predators decreased overt aggression in response to exposure to predator chemical cues. Plastic responses to the predator cue were lower in killifish from sites that lack predators. Interestingly, wild fish from sites without predators did respond to the predator cue by decreasing overt aggression and increasing time spent frozen, though to a lesser degree compared to the fish from sites with predators. Our results support the expectation that development in a risky environment favours evolutionary changes in predator-mediated behavioural plasticity.
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- Award ID(s):
- 2236741
- PAR ID:
- 10670905
- Editor(s):
- Gonzalez-Voyer, Alejandro; Carazo, Pau
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Evolutionary Biology
- Volume:
- 38
- Issue:
- 5
- ISSN:
- 1420-9101
- Page Range / eLocation ID:
- 572 to 579
- 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/10.1093/jeb/voaf024
