BEVIER, C.R.*; GOMES, F.R.; NAVAS, C.A.: Diversity of calling behavior within a genus of tropical treefrogs: relationships with habitat structure and energetics

Calling behavior in frogs is a highly diverse activity with remarkable interspecific variation in call structure and calling effort, even within a single genus. We explored interspecific variation in calling behavior in eight species of treefrogs in the genus Scinax (Hylidae) to ask 1) how behavioral variation may be influenced by habitat structure and phylogenetic affinities, and 2) what are the metabolic correlates of this variation. The genus Scinax is highly diverse across habitat types in the Atlantic Rainforest of Brazil, in which three species groups are particularly common (ruber, catharinae and perpusillus). Species in the ruber group produce simple pulsed calls at relatively high calling rates, and tend to call in open habitats from either the ground or perches. In contrast, species from the perpusillus and catharinae groups produce more complex calls in bouts with a broadly varied repertoire, call in forested areas from the margins of small ponds, slow-moving streams, or from bromeliads, and tend to exhibit lower calling rates. This dichotomy between call complexity and calling effort might reflect restrictions in potential for effective acoustic communication at long distances, degree of territoriality, or both. In addition, we found that species with high calling efforts also had relatively high activity metabolic rates to support this level of performance.