title: The DeAngelis-Beddington functional response and the evolution of timidity of the prey.
abstract: We study the evolution of "timidity" of the prey (i.e., its readiness to seek refuge) in a predator-prey model with the DeAngelis-Beddington functional response. Using the theory of adaptive dynamics, we find that a predator-prey population at equilibrium always favours less timidity. Low levels of timidity, however, may destabilise the population and lead to cycles. Large-amplitude cycles favour a positive level of timidity, but if such cycles do not occur, timidity will evolve all the way to zero, where the prey no longer responds to the predator by seeking refuge, and in which case the DeAngelis-Beddington functional response has become identical to the Holling type-II functional response.
authors.affiliation: Department of Mathematics and Statistics, P.O. Box 68, FI-00014 University of Helsinki, Finland. Electronic address: stefan.geritz@helsinki.fi.
authors.forename: Stefan A H
authors.initials: SA
authors.lastname: Geritz
authors.affiliation: Department of Mathematics and Statistics, P.O. Box 68, FI-00014 University of Helsinki, Finland.
authors.forename: Mats
authors.initials: M
authors.lastname: Gyllenberg
mesh_terms: D000818:Animals; D005075:Biological Evolution; D004924:Escape Reaction / Q000502:physiology; D020387:Food Chain; D056084:Genetic Fitness; D008962:Models, Theoretical; D011157:Population Dynamics; D011235:Predatory Behavior / Q000502:physiology*; D012792:Shyness
keywords: Adaptive dynamics; Mechanistic model; Predator–prey; Prey refuge; Separation of timescales