Evolutionarily stable learning schedules and cumulative culture in discrete generation models

Area of Science:

• Evolutionary biology
• Behavioral ecology
• Learning theory

Background:

• Organisms acquire and express phenotypes through individual learning (e.g., trial-and-error) and social learning (e.g., imitation).
• The optimal learning strategy can depend on an organism's life stage.
• Social learning preceding individual learning is crucial for the development of cumulative culture.

Purpose of the Study:

• To determine evolutionarily stable learning schedules under different environmental conditions.
• To investigate the optimal sequence of individual and social learning stages.
• To identify learning schedules that optimize learned phenotypes at equilibrium.

Main Methods:

• Modeling evolutionarily stable learning schedules across three environmental scenarios: constant, fluctuating between generations, and fluctuating within generations.
• Assuming two obligatory learning stages per generation, with options for individual learning and/or social learning at each stage.
• Analyzing learning schedules in the absence of exogenous learning costs.

Main Results:

• Predicted evolutionarily stable learning schedules are either pure social learning followed by pure individual learning ("bang-bang" control) or pure individual learning at both stages ("flat" control).
• These stable schedules were identified for constant, between-generation, and within-generation fluctuating environments.
• The evolutionarily stable learning schedule consistently optimizes the learned phenotype at equilibrium for each environmental scenario.

Conclusions:

• The optimal learning strategy involves distinct stages, with social learning often preceding individual learning to facilitate cumulative culture.
• "Bang-bang" and "flat" control represent the primary evolutionarily stable learning schedules.
• These schedules ensure optimal phenotype acquisition and expression across various environmental dynamics.