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08:10
A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants
Published on: October 12, 2018
Behavioral mechanisms underlie an ant-plant mutualism
Jennifer A Rudgers1, Jillian G Hodgen, J Wilson White
1Center for Population Biology, University of California, One Shields Avenue, Davis, CA 95616, USA. jrudgers@indiana.edu
Oecologia
|March 21, 2003
Summary
Predatory ants significantly reduced wild cotton plant damage by altering caterpillar behavior, not just by eating them. These non-consumptive predator effects demonstrate trait-mediated cascades in plant-insect interactions.
Area of Science:
- Ecology
- Behavioral Ecology
- Plant-Insect Interactions
Background:
- Predators impact herbivores through direct consumption and non-consumptive effects (NCEs) that alter prey behavior and physiology.
- NCEs can significantly influence ecological dynamics, but their cascading effects on prey's resources, like host plants, are less understood in terrestrial systems.
Purpose of the Study:
- To investigate if non-consumptive effects of predatory ants influence the host plants of herbivorous prey.
- To examine the role of trait-mediated effects of ants on wild cotton plants via their impact on a specific folivore.
Main Methods:
- Conducted season-long ant exclusion experiments on wild cotton (Gossypium thurberi) to assess ant impact on folivore damage and abundance.
- Performed behavioral experiments over two years and in two populations to observe caterpillar (Bucculatrix thurberiella) behavior in the presence and absence of ants.
Main Results:
- Ant exclusion led to proportionally more herbivore damage than reduced herbivore abundance, indicating strong NCEs.
- Caterpillars exhibited reduced feeding behavior (less stationary time, more dropping) and altered spatial distribution (more time on upper leaf surfaces, damage further from margins) when ants were present.
- Both direct ant encounters and indirect cues (ants on leaves) triggered anti-predator behaviors in caterpillars.
Conclusions:
- Predatory ants exert significant trait-mediated effects on wild cotton plants by altering herbivore behavior.
- Non-consumptive effects of predators can cascade to influence host plants, highlighting the ecological importance of predator-prey interactions beyond direct consumption.
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