The niche variation hypothesis (NVH) predicts that populations with broader niches should exhibit greater between- individual diet variation or individual specialization (IS) relative to populations with narrower niches. ...

The order Passeriformes comprises the largest number of families and species of birds of any avian order. Brazil is rich in passerine birds, which are a common victim of wildlife trafficking in Brazil. Annually, many birds ...

We studied the osmoregulatory responses of the granivore Zonotrichia capensis, acclimated to high- and low-protein diets as well as two levels of water intake. We tested whether Z. capensis has the ability to modify the ...

Background. Passerine birds exploit different kinds of feeding habits and they have to face seasonal changes in food availability. Therefore, the composition of the principal nutrient in their food differs from the usual. ...

Cactus flowers have traditionally been considered to be specialized to certain pollination guilds, but pollination studies reveal that most species are actually generalists. This suggests that floral traits are not always ...

The cloud forest species Meriania macrophylla (Benth.) Triana has pseudocampanu- late flowers with bulbous stamen appendages, typical for the passerine pollination syndrome found in the Melastomataceae tribe Merianieae. ...

Plants in the genus Erythrina are pollinated by birds, such that passerine pollination is the plesiomorphic state, whereas hummingbird pollination is the derived character. Phylogenetic studies suggest that Erythrina ...