Pathways to the density-dependent expression of cannibalism, and consequences for regulated population dynamics
Jay A Rosenheim1, Sebastian J Schreiber2
1Department of Entomology and Nematology, University of California, Davis, California, USA.
Ecology
|July 12, 2022
Summary
Cannibalism is a widespread behavior that regulates populations by increasing mortality as population density rises. This density-dependent mortality stabilizes populations but can also lead to alternative ecological states.
Area of Science:
- Ecology
- Population Dynamics
- Behavioral Ecology
Background:
- Cannibalism was historically considered rare but is now understood as a common population self-regulation mechanism.
- It functions as a conditional behavior, intensifying with increased conspecific density and deteriorating ecological conditions.
Purpose of the Study:
- To synthesize current research on the diverse pathways through which population density increases cannibalism.
- To explore the population dynamics consequences of density-dependent cannibalism using mathematical models.
Main Methods:
- Review of recent scientific literature on the ecological and behavioral factors influencing cannibalism.
- Application of mathematical modeling to simulate population dynamics with density-dependent cannibalism.
Main Results:
- Density-dependent cannibalism acts as a significant source of mortality, contributing to population regulation.
- Increased density elevates cannibalism through more dangerous encounters and higher attack success rates.
- Factors include species' autecology and interactions with resources and pathogens.
Conclusions:
- Conditional cannibalism generally promotes stability and regulation in single-species populations.
- However, it can also create conditions for alternative population states and escape from predator control.
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