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Pulsed-resource dynamics constrain the evolution of predator-prey interactions
Ville-Petri Friman1, Jouni Laakso
1Centre of Excellence in Evolutionary Research, Department of Biological and Environmental Science, University of Jyväskylä, Finland. vifriman@gmail.com
The American Naturalist
|April 5, 2011
Summary
Resource pulses impact species interactions. Rapid prey evolution to defense is weaker under fluctuating resources, altering predator-prey dynamics and community regulation.
Area of Science:
- Ecology
- Evolutionary Biology
- Microbial Ecology
Background:
- Temporal environmental variability influences population dynamics.
- The effects of resource pulses on species interaction dynamics are understudied.
Purpose of the Study:
- To investigate how extrinsic resource pulses affect evolutionary and ecological dynamics.
- To examine the interplay between prey defense evolution and predator-prey interactions under varying resource conditions.
Main Methods:
- Experimental study using the bacterium Serratia marcescens (prey) and protozoan Tetrahymena thermophila (predator).
- Manipulation of resource availability (constant vs. pulsed environments).
- Monitoring of prey defensive traits, growth rates, and predator population dynamics.
Main Results:
- Predation favored defensive, nonpigmented prey, incurring competitive growth costs.
- Pulsed resources led to fluctuating selection for prey defense, resulting in a weaker average defense response.
- Evolution of prey defense reduced top-down regulation, with effects differing between constant and pulsed environments.
Conclusions:
- Rapid prey evolution plays a lesser role in the ecological dynamics of communities experiencing resource pulses.
- Environmental variability, specifically resource pulsing, can decouple ecological and evolutionary dynamics.
- The study highlights the importance of considering temporal resource dynamics in ecological and evolutionary research.
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