Frugivory is widespread among birds and, at first glance, it is difficult to suggest states of external characters that would separate frugivorous birds from omnivores and carnivores. In the literature it has been suggested that body size and gape width increase with frugivory. It also has been stated that powerful morphological constraints act on behavioural differences among fruit-eating birds. This relates mainly to the way fruits are obtained by the birds, namely either on the wing or from a perch. We analysed behaviour and external morphological characters of Neotropical birds in a lowland rain forest in southern Venezuela to address these problems. Morphologically speaking, frugivores formed an ill defined subset of this avian community. Body size and gape width did not show a consistent relationship with frugivory. Reaching out and down, as well as taking fruits on the wing were the most common techniques used apart from simple gleaning. Body size constrains the evolution of corresponding characters. Evolutionary speaking, there are many roads to frugivory and only careful analyses of behavioural observations, and ecological data, paired with morphological considerations can uncover the general rules behind this diversity.
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