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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 $\theta$- model equation for a periodic carrying capacity K(t) and $t\succcurlyeq r\sp{-1}$ is identical in form to the generalized logistic equation solution with a built-in developmental time delay $\tau (\preccurlyeq r\sp{-1})$ and associated parameter ranges of primary biological interest. In the case of the $\theta$-model equation, the time delay is a purely dynamical consequence of the nonlinear form featured by the population growth rate.

##### MSC:
 92D25 Population dynamics (general) 34A45 Theoretical approximation of solutions of ODE 34A34 Nonlinear ODE and systems, general
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##### References:
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