M Predator To investigate trait variation, fN,M fN,M we consider a tri-trophic chain of resource r consumer N, and predator M onsumer 1 The consumer is assumed to m2 n2 have two phenotype subpopulations( with different strategies) and there is some switching back a,RN1 2RN2 and forth between the twoM Predator N1 Consumer 1 N2 Consumer 2 R Resource a2RN2 a1RN1 f2N2M f1N1M m12N1 m21N2 To investigate trait variation, we consider a tri-trophic chain of ‘resource R’, ‘consumer N’, and ‘predator M’ The consumer is assumed to have two phenotype subpopulations (with different strategies) and there is some switching back and forth between the two