An Evolutionary Game Model of Sex-Dependent Antipredator Signaling

Area of Science:

• Evolutionary biology
• Behavioral ecology
• Game theory

Background:

• Prey animals often display conspicuous behaviors as antipredator signals.
• Signaling frequencies can differ between sexes in many species, leading to sexual dimorphism.

Purpose of the Study:

• To theoretically assess the evolution of inter- and intrasexual dimorphism in antipredator signaling.
• To model the specific case of the Chinese grasshopper (Acrida cinerea), where only some males signal.

Main Methods:

• Development of an evolutionary game model.
• Incorporation of costs associated with signaling, including individual predation risk and collective effects on conspecifics.

Main Results:

• A positive individual effect is crucial for antipredator signaling evolution.
• Sexual dimorphism in fecundity costs or predation risk can drive intersexual signaling dimorphism.
• A positive collective effect explains intrasexual dimorphism, where only a subset of one sex signals.

Conclusions:

• The study presents the first model for intrasexual dimorphism in antipredator signaling.
• The model provides testable predictions for the evolution of antipredator behaviors.