Abstract: In this work, we consider populational growth models with Allee effect. These models are proportional to beta densities with shape parameters p and 2, where the dynamical complexity is related with the malthusean parameter r. For p>2, these models exhibit a population dynamics with natural Allee effect. However, in the case of 1, the proposed models do not include this effect. In order to invoke the Allee effect, we present some alternative mechanisms and investigate their dynamics. Using dynamical symbolic techniques, we analise the complex behaviour of these models, in terms of topological entropy, in the parameter plane (r,p), defining different dynamical regimes.

Keywords: Beta Densities, Population Dynamics, Topological Entropy and Allee Effect.

MSC2000 Classification: 60E05, 92D25, 37B10, 37B40

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