Influência da massa corporal, da filogenia e do habitat sobre a estrutura da vocalização de aves brasileiras

Abstract

Communication is a very important factor for the maintenance of several vital ecological processes among animals. Among birds, the acoustic communication has primordial role and it is indispensable for reproduction, to repel predators and in social dynamics. Body size imposes physiological constraints to the vocal apparattus, and consequently, limits the components of vocalizations. The environment also inflicts certain physical restrictions to the acoustic signs and limits the transmissibility of information. The Acoustic Adaptation Hypothesis (HAA) predicts a different selection for vocalization characters in forest habitats. Specifically, frequencies in forest habitats tend to be affected by attenuation, absorption and reverberation, effects imposed by physical barriers in this environment. The present work tested the HAA using 142 bird species and five major clades widely distributed in Brazil, considering body size and two phylogenetic comparative methods: pairwise comparisons and phylogenetic independent contrasts. None of the Suboscine vocal characters were correlated to morphology. Most of the predictions of AAH were not corroborated and varied between clades.