Latitudinal gradients in predation persist in urban environments

Abstract

AbstractUrbanization can profoundly disrupt local ecology. But while urban areas now stretch across latitudes, little is known about urbanization’s effects on macroecological patterns. We used standardized experiments to test whether urbanization disrupts latitudinal gradients in seed predation, a macroecological pattern that shapes community assembly and diversity. Using >56,000 seeds, we compared predation in urbanized and natural areas across 14,000 km of latitude, spanning the Americas. Predation increased 5-fold from high latitudes to the tropics, and latitudinal gradients in predation persisted in urban areas despite significant habitat modification. Urbanization reduced predation by vertebrates, but not invertebrates, and seemed to increase ant predation specifically. Our results show that macroecological patterns in predation intensity can persist in urbanized environments, even as urbanization alters the relative importance of predators.One-Sentence SummaryAcross 56,000 seeds and 112° of latitude, latitudinal gradients in seed predation are equally strong in natural vs. urban areas