  Similarity of competitors has been proposed to facilitate coexistence of
species because it slows down competitive exclusion, thus making it easier for
equalizing mechanisms to maintain diverse communities. On the other hand, chaos
can promote coexistence of species. Here we link these two previously unrelated
findings, by analyzing the dynamics of food web models. We show that
near-neutrality of competition of prey, in the presence of predators, increases
the chance of developing chaotic dynamics. Moreover we confirm that this
results in a higher biodiversity. Our results suggest that near-neutrality may
promote biodiversity in two ways: through reducing the rates of competitive
displacement and through promoting non-equilibrium dynamics.
