Two-phase Age-Structured Model of Solitarious and Gregarious Locust Population Dynamics
نویسندگان
چکیده
1 Faculty of Cybernetics, T.Shevchenko National University of Kyiv, Volodymyrska 64, 01030 Kyiv, Ukraine. 2 CIRAD, UMR CBGP, F-34398 Montpellier, France & CNLAA, BP125, 86343 Inezgane, Morocco & University Ibn Zohr, Agadir, Morocco Abstract In this paper we study a nonlinear age-structured model of locust population dynamics with variable time of egg incubation that describes the phase polyphenism and behaviour of desert locust, Schistocerca gregaria. The model is based on the competitive system of linear transport Eqs. with nonlinear density-dependent fertility rates with variable time delay in boundary conditions. It describes the dynamics of the density of two subpopulations or two phases of locust’s polyphenism – solitarious and gregarious. The obtained system is studied both theoretically and numerically. The analysis of asymptotical stability of trivial and nontrivial equilibriums of autonomous system allows us to derive the conditions and understand the particularities of bidirectional phase transitions between solitarious and gregarious. Simulation of locust population dynamics with different conditions of phase transitions for autonomous and non-autonomous dynamical systems of our two-phase age-structured competitive model with time delay exhibits the features of behaviour of documented outbreak dynamics of Schistocerca gregaria.
منابع مشابه
Locust Dynamics: Behavioral Phase Change and Swarming
Locusts exhibit two interconvertible behavioral phases, solitarious and gregarious. While solitarious individuals are repelled from other locusts, gregarious insects are attracted to conspecifics and can form large aggregations such as marching hopper bands. Numerous biological experiments at the individual level have shown how crowding biases conversion towards the gregarious form. To understa...
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