Three Logistic Models for the Two-Species Interactions: Symbiosis,   Predator-Prey and Competition
  If one isolated species is supposed to evolve following the logistic mapping, then we are tempted to think that the dynamics of two species can be expressed by a coupled system of two discrete logistic equations. As three basic relationships between two species are present in Nature, namely symbiosis, predator-prey and competition, three different models are obtained. Each model is a cubic two-dimensional discrete logistic-type equation with its own dynamical properties: stationarity, periodicity, quasi-periodicity and chaos. Furthermore, these models could be considered as the basic ingredients to construct more complex interactions in the ecological networks. 
R. Lopez-Ruiz and D. Fournier-Prunaret