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Time delays produced by essential nonlinearity in population growth models. (English) Zbl 0614.92015
It is pointed out that the asymptotic general solution to the θ- model equation for a periodic carrying capacity K(t) and tr -1 is identical in form to the generalized logistic equation solution with a built-in developmental time delay τ(r -1 ) and associated parameter ranges of primary biological interest. In the case of the θ-model equation, the time delay is a purely dynamical consequence of the nonlinear form featured by the population growth rate.
MSC:
92D25Population dynamics (general)
34A45Theoretical approximation of solutions of ODE
34A34Nonlinear ODE and systems, general