Birds optimize fruit size consumed near their geographic range limits.

Animals can adjust their diet to maximize energy or nutritional intake. For example, birds often target fruits that match their beak size because those fruits can be consumed more efficiently. We hypothesized that pressure to optimize diet-measured as matching between fruit and beak size-increases under stressful environments, such as those that determine species' range edges.

Global and regional ecological boundaries explain abrupt spatial discontinuities in avian frugivory interactions.

Species interactions can propagate disturbances across space via direct and indirect effects, potentially connecting species at a global scale. However, ecological and biogeographic boundaries may mitigate this spread by demarcating the limits of ecological networks. We tested whether large-scale ecological boundaries (ecoregions and biomes) and human disturbance gradients increase dissimilarity among plant-frugivore networks, while accounting for background spatial and elevational gradients and differences in network sampling.

Responses of functional traits in cavity-nesting birds to logging in subtropical and temperate forests of the Americas.

Logging causes changes in habitat structure, which can potentially lead to variations in taxonomic and functional richness of biodiversity. Studies on how functional traits in birds are affected by logging operations can provide an important element for the understanding of ecosystem processes. In this paper, we examined how logging in subtropical Andean forests influenced taxonomic and functional diversity of cavity-nesting birds.

Fine-tuning the fruit-tracking hypothesis: spatiotemporal links between fruit availability and fruit consumption by birds in Andean mountain forests.

1. The fruit-tracking hypothesis predicts spatiotemporal links between changes in the abundance of fruit-eating birds and the abundance of their fleshy-fruit resources. 2.