On the Periodic Lotka]Volterra Competition Model

We analyze the existence, stability, and multiplicity of T-periodic coexistence states for the classical nonautonomous periodic Lotka]Volterra competing species model. This is done by treating the average values of the birth rates of species as parameters, and studying the global structure of the set of coexistence states as these parameters vary. As a result of this analysis, we can explain the interesting differences between the results for the periodic case and the associated autonomous model