Time-dependent animal conflicts: 1. The symmetric case

Area of Science:

• Behavioral Ecology
• Evolutionary Game Theory
• Population Dynamics

Background:

• Animal conflicts often involve time-dependent strategies, particularly when group members require assistance.
• Individuals at risk face a time-dependent mortality rate until help is received.
• Potential helpers incur costs for assisting but face reduced inclusive fitness if the at-risk individual dies.

Purpose of the Study:

• To model animal conflicts where one member's survival depends on timely assistance from others.
• To investigate how the observability of helper strategies influences the evolutionarily stable strategies (ESS).
• To apply the model to classic problems like the 'n brothers' problem and parental investment conflicts.

Main Methods:

• Developed a game-theoretic model analyzing time-dependent strategy sets in animal conflicts.
• Assumed potential helpers choose probability distributions for their assistance timing.
• Analyzed the impact of strategy realization observability on the existence and nature of ESS.

Main Results:

• When strategy realizations are observable, ESS always exist, including immediate assistance, no assistance, and delayed assistance.
• When strategy realizations are unobservable, ESS do not always exist; immediate assistance and no assistance are possible ESS.
• Delayed assistance is not a stable ESS when helper actions are unobservable.

Conclusions:

• Observability of actions is crucial for the stability of cooperative strategies in animal conflicts.
• The model provides insights into the evolution of helping behaviors and strategic interactions within animal groups.
• Findings have implications for understanding kin selection and conflict resolution in social animals.