My main area of interest concerns the structuring of bat faunas in the Antilles as compared to mainland communities. This is done by examining aspects of ecomorphology, physiology, habitat diversity, and species interactions related to roosting, foraging behavior, and patterns of activity. Archipelagos provide better models than continents for examining the relative importance of deterministic (i.e. area, habitat diversity, distance from source habitat, and competition) and stochastic (i.e. dispersal and persistence independent of interactions) factors in structuring bat communities. In continents, where community structures often are indistinguishable from those produced by stochastic processes, local extinctions resulting from competitive interactions might be blurred by immigration from source habitats.