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Interpopulation variation in a fish predator drives evolutionary divergence in prey in lakes
Matthew R Walsh1, David M Post
1Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520, USA. matthew.walsh@yale.edu
Proceedings. Biological Sciences
|January 29, 2011
Summary
Predator behavior influences prey evolution. Zooplankton (Daphnia ambigua) evolved faster growth and reproduction in response to seasonal alewife predation, adapting to colder conditions.
Area of Science:
- Ecology
- Evolutionary Biology
- Freshwater Ecology
Background:
- Ecological factors drive evolutionary diversification.
- Predator evolution can impact ecosystems and alter prey selective landscapes.
- Intraspecific variation in prey evolution remains understudied.
Purpose of the Study:
- To investigate the link between intraspecific variation and evolution in prey species.
- To compare zooplankton (Daphnia ambigua) life history in relation to predator (alewife) traits and behavior.
- To explore how predator-induced selection shapes prey adaptation.
Main Methods:
- Comparative life history analysis of Daphnia ambigua from New England lakes.
- Studied lakes with differing alewife (Alosa pseudoharengus) feeding traits and migratory behaviors (anadromous vs. landlocked).
- Experimental treatments across varying temperatures and resource levels.
Main Results:
- Daphnia from lakes with anadromous alewife exhibited faster growth, earlier maturation, and higher offspring production.
- These life-history differences were observed across multiple temperature and resource treatments.
- Results suggest adaptation to colder temperatures and shorter development periods (countergradient variation), not size-selective predation.
Conclusions:
- Seasonal alewife predation can mediate countergradient variation in Daphnia ambigua.
- Predator-prey interactions play a crucial role in shaping prey life-history evolution.
- Intraspecific variation in predator behavior can lead to divergent evolutionary trajectories in prey populations.
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