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Producer-Scrounger Game. Role of Experience, Learning What is learned? Environmental quality (patch size) Payoffs different roles Morand-Ferron & Giraldeu (2010, Behav Ecology). Producer-Scrounger Game. Producer: Generates opportunities to exploit resource
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Producer-Scrounger Game Role of Experience, Learning What is learned? Environmental quality (patch size) Payoffs different roles Morand-Ferron & Giraldeu(2010, Behav Ecology)
Producer-Scrounger Game Producer: Generates opportunities to exploit resource Finder’s share; Cost of production Scrounger: Exploits producer-generated resources Smaller share; No cost of production Exploit multiple producers
Nash Equilibrium Probability of Energetic Failure 0 2 4 6 8 10 12 14 Number of Scroungers (S)
Nash Equilibrium Probability of Energetic Failure 0 2 4 6 8 10 12 14 Number of Scroungers (S)
Producer-Scrounger Game Producer invades scrounger AND Scrounger invades producer ESS: 0 < q* < 1 where WS(q*) = WP(q*) Equilibrium predicted by game: How close? Role of learning?
Morand-Ferron & Giraldeau (2010) Learning Increase rate of ”correct” response Reduce errors Reduce time delay for correct response Learning the ESS: “behaviorally stable solution” Permits individual to respond to change Resource or social environment
Morand-Ferron & Giraldeau (2010) Learning Nutmeg mannikin P-S Interaction n-Person Game
Morand-Ferron & Giraldeau (2010) Aviary Flock composition fixed, 5 birds/flock Grid, 100 wells, millet seeds hidden Initial experience Low scrounging: 5 seeds in 40 wells High scrounging: 10 seeds in 20 wells Food Spatially homogeneous, heterogeneous
Morand-Ferron & Giraldeau (2010) Experiment: Test in minimal or high-scrounging environment 2 seeds in each well 20 seeds in 10 wells Individuals: Proportion of patches scrounged, among patches visited Nash equilibrium differed between environments Estimated from mean feeding rates High-scrounging: q* = 0.39
Morand-Ferron & Giraldeau (2010) Discussion First demonstration learning in P-S game 1. Adjustment to environment 2. Persistent effect of experience Weigh past and recent experience Learning context can affect what is learned