Patrícia Ferreira Monticelli

Isolation induced changes in Guinea Pig Cavia porcellus pup distress whistles

Guinea Pig Cavia porcellus pups emit high-pitched distress whistles when separated from their mother. In order to assess the influence of the duration of a brief isolation period on whistle acoustic structure, we recorded the distress whistles of six 8-day old pups separated for 15 min from their group in a novel environment and compared the mean values of the first and last 30 whistle notes. Acoustic analysis revealed, throughout the session, a significant decrease in whistle duration, an increase in mean frequency and a tendency for a decrease in number of harmonics in the first part of the note. Results demonstrate that, throughout a brief isolation period, the vocal response of Guinea Pig pups to isolation undergoes structural changes possibly related to time-dependent changes in motivational state.

BIOACOUSTICS OF DOMESTICATION: ALARM AND COURTSHIP CALLS OF WILD AND DOMESTIC CAVIES

ABSTRACT Comparisons of wild (Cavia aperea) and domestic (C. porcellus) cavies promote an understanding of the physiological and behavioral effects of domestication. The richness and peculiarities of Cavia acoustic repertoires encourage the use of this model for testing how domestication alters repertoires and the physical structure of calls. We present a comparison between alarm and courtship calls of domestic and two populations of wild cavies from different geographic regions, one of them with a short-term captivity history of 25 generations. We found significant differences between domestic and wild cavies in both calls, particularly in temporal parameters, and only spectral differences between two wild populations in alarm calls. There were also differences in the frequency of emission of calls: alarm calls were more frequent in the wild and courtship calls were more frequent in the domestic species. Our results suggest that domestication has influenced the temporal parameters of both alarm and courtship calls of C. porcellus, but not the spectral parameters that, instead, may be influenced by environment or population factors.

INDIVIDUAL DIFFERENCES IN INFANT GUINEA PIG PUPS ISOLATION WHISTLES

ABSTRACT When separated from their mother and other group members, guinea pig Cavia porcellus pups emit distinctive high pitched whistles. To determine if these vocalisations are individually distinctive, we recorded the whistles of isolated guinea pig pups, 8 to 10 days old, and subjected their acoustical parameters to discriminant analysis. The results of the reclassification accuracy were higher than random assignment, indicating the existence of individual differences. Individual pup vocalisations did not differ from one another by any single acoustic parameter, but by a set of parameters. Individual recognition of such isolation calls by mothers could play an important role in facilitating reestablishment of contact.

Allosuckling in a captive group of wild cavies Cavia aperea

Abstract We took the rare opportunity to observe and quantify spontaneous allosuckling in a captive group of Cavia aperea captured in the wild (a male, two females and their offspring). We recorded behavior interactions between all offspring and each of the adults between days 6 and 20 of life. Infants suckled equally from their mother and from the other female, which differs from a previous report in which mothers typically nursed own young. In addition, infants stayed closer to the other female than to mother or to the father. We discuss these results in the light of the common occurrence of allosuckling in Cavioidea and social structure.

The communicative life of a social carnivore: acoustic repertoire of the ring-tailed coati (Nasua nasua)

Abstract The coati is a highly social mammal that features sophisticated cognitive and social abilities. We hypothesized that the ring-tailed coati, Nasua nasua, uses an extensive acoustic repertoire that correlates to their diverse range of social interactions. We tested this hypothesis by observing and recording a free-ranging managed population of N. nasua in Tietê Ecological Park (PET), in the municipality of São Paulo, State of São Paulo, Brazil. Of 404 h of sampling, 47 h of coati vocalizations were recorded over 3 years. Additional records were obtained opportunistically on other free-living populations at PET by using passive acoustic monitoring. We describe here an acoustic repertoire composed of 15 calls (12 basic calls, 2 rhythmic calls and the non-random complex calls composed of three or four different units). This diverse repertoire of signals was used in contact/cohesion regulation, foraging activities, alert or potential threat situations, playing and fighting interactions and during social isolation and acute distress. The contact call (chirp) is produced through biphonation, and other non-linear phenomena are present. Our study found a complex vocal repertoire that encourages further studies to describe the evolution of the cognitive characteristics and social abilities of ring-tailed coatis.