Toucans and thrushes as potential dispersers of seed-predatory weevil larvae in southeastern Brazil

Abstract

Only recently have the interrelationships between seed-predatory insects and frugivores (seed dispersers) been considered of interest for evolutionary studies. Within the framework of "evolutionary triads," insect dispersion by frugivores that eat insect-infested fruits has been predicted. Such dispersal requires that insects survive passage through frugivore stomachs. In this paper we document this in the case of a weevil (Revena rubiginosa) infesting the nut of a palm tree (Syagrus romanzoffiana) and an unidentified weevil infesting the seed of a tree belonging to the genus Eugenia (Myrtaceae). The fruits of both trees are eaten by toucans (Ramphastos dicolorus and R. vitellinus) and those of the palm also by thrushes (Turdus rufiventris).