1. Hedonic models of fish behaviour Sigrunn Eliassen Department of Fisheries and Marine Biology University of Bergen

2. Hedonic models zAdaptive behaviour in IBM zProximate linked to ultimate factors zIndividuals exposed to complex environmental stimuli zAffective responses to stimuli determines behavioural responses zMotivation for behaviour is genetically determined zCombinations of hedonic “genes” evolve over generations

3. Proximate approach: responses to stimuli External and internal stimuli AffectAffect Behaviour

4. The Genetic Algorithm (GA) REPRODUCTION MUTATION & RECOMBINATION SELECTION

5. The hedonic model zIndividual combinations of “genes” regulate the sensitivity to stimuli and response patterns associated with different affect systems za “chromosomal” representation of possible solutions to the problem zin GA the performance of the individual genetic solutions are evaluated za reproduction function is included to produce next set of possible solutions za mutation operator to introduce stochastic changes in solutions

6. Model of vertical migration in fish zA vertical environment, where light and temperature decreases towards the bottom zDiel light variation zDiel vertical migration of food, relative to light zLight-dependent prey encounter rate zMortality risk depends on probability of being detected by predator, i.e. of light zBoth growth and survival are density-dependent

7. DD DI Generation 1 10 200 1000 2000

8. Model of vertical migration in fish zContinuos generations zRealistic physiology and environmental conditions zCoevolving populations zLearning copepods