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Published on: July 20, 2017
Predation risk influences adaptive morphological variation in fish populations
Peter Eklöv1, Richard Svanbäck
1Limnology Section, Department of Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Norbyvägen 20, SE-752 36 Uppsala, Sweden. peter.eklov@ebc.uu.se
The American Naturalist
|May 5, 2006
Summary
Predator presence indirectly influences prey fish morphology by altering habitat use and diet. This behavioral shift, driven by predation risk, leads to adaptive morphological variation in young perch.
Area of Science:
- Ecology
- Evolutionary Biology
- Behavioral Ecology
Background:
- Predators can drive phenotypic divergence in prey populations.
- Indirect effects of predators on prey behavior and morphology are less understood.
- Predation risk can influence prey habitat selection and resource use.
Purpose of the Study:
- To investigate how predation risk influences prey behavior and subsequent morphology.
- To determine if experimental findings explain natural morphological variation in perch.
- To assess the role of indirect predator effects in adaptive evolution.
Main Methods:
- A pond experiment manipulating predation risk across different habitats.
- Observing prey fish behavioral shifts in response to predator cues.
- Analyzing the correlation between prey diet, morphology, and habitat use.
- Comparing experimental results with field data on perch morphology and growth.
Main Results:
- Prey fish moved to lower-risk habitats when predators were present.
- Habitat specialization led to diet specialization and correlated morphological variation.
- Morphological variation was linked to predation risk, not competition or mortality.
- Field studies confirmed morphology-driven growth differences in perch across habitats.
Conclusions:
- Predation risk indirectly induces adaptive morphological variation in prey through behavioral changes.
- A trade-off between foraging and predator avoidance shapes prey morphology.
- Indirect ecological interactions are significant drivers of evolutionary responses in prey populations.
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