  We analyze the role of the Allee effect, a positive correlation between
population density and mean individual fitness, for ecological communities
formed by a large number of species. Our study is performed using the
generalized Lotka-Volterra model with random interactions between species. We
obtain the phase diagram and analyze the nature of the multiple equilibria
phase. Remarkable differences emerge with respect to the case of the logistic
growth case, thus revealing the major role played by the functional response in
determining aggregate behaviours of ecosystems.
