Acoustic analysis of vocalization and the behavioral response associated to sound production of the nine banded armadillo Dasypus novemcinctus (Mammalia, Cingulata, Dasypodidae) in an agonistic context

Although communication capabilities are displayed by many vertebrate groups, some repertoires are poorly known, such as the case of xenarthrans, particularly armadillos, for which vocalization as a source of communicating to others remains poorly understood and relies on punctual reports of sounds. Here we provide the first description of a behavioral response associated with sound emission of two subjects of Dasypus novemcinctus. Both audio and visual registration was performed to subsequent analyses of expressed behaviors and emitted calls, which accounted for 76 vocalizations from a total of eight video recordings randomly collected from 2017 to 2019. Sound is acoustically characterized by both inhale and exhale phases composed of two vocal units, and no harmonic structure was observed. Once the subjects have always produced these vocalizations while cornered and exhibiting defensive behavior against another subject/human disturbance, these vocalizations were termed as distress. Subjects produced a hiss-purr-like sound while trying to avoid contact with another by bowing or lowering their bodies, humping, or even moving elsewhere when sound production ceased. This shows that the sound repertoire of armadillos is still to be unveiled and seems to be much more complex than previously thought

Diversity and evolution of the extraordinary vocal sacs of casque-headed treefrogs (Anura: Hylidae)

Vocal sacs are among the most conspicuous features of anurans and are particularly striking in casque-headed treefrogs (Hylidae: Hylinae: Lophyohylini) with their wide array of morphologies. In this paper, we assessed the anatomy of vocal sacs in representatives of the Lophyohylini, described eight discrete characters and studied their evolution. We inferred that dorsolateral projections of the vocal sacs were already present during the early evolution of the tribe. Subsequently, they reached surprising volumes in some species, whereas in others they were notably reduced. We inferred between nine and 11 independent events of reduction of the size and lateral projections of the vocal sac, showing unprecedented levels of plasticity for the structure. Moreover, these events were strongly correlated with the colonization of phytotelmata as breeding sites, probably due to their confined space which hampers the inflation of large vocal sacs. Finally, we discuss the evolution of paired lateral vocal sacs in different groups of anurans, and the extent to which the paired and dorsally-projecting lobes of most Trachycephalus differ from those of distantly related taxa. Our findings highlight how variation in internal structure affects the shape of the inflated vocal sac and provides a framework applicable across the Anura.Fil: Moura, Pedro Henrique Areco Gomes. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Elías Costa, Agustín Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Nunes, Ivan. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Faivovich, Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentin