Through the eyes of children: perceptions of environmental change in tropical forests.

This study seeks to understand children's perceptions of their present and future environments in the highly biodiverse and rapidly changing landscapes of Kalimantan, Indonesian Borneo. We analyzed drawings by children (target age 10-15 years) from 22 villages, which show how children perceive the present conditions of forests and wildlife surrounding their villages and how they expect conditions to change over the next 15 years. Analyses of picture elements and their relationships to current landscape variables indicate that children have a sophisticated understanding of their environment and how different environmental factors interact, either positively or negatively.

People's perceptions about the importance of forests on Borneo.

We ascertained villagers' perceptions about the importance of forests for their livelihoods and health through 1,837 reliably answered interviews of mostly male respondents from 185 villages in Indonesian and Malaysian Borneo. Variation in these perceptions related to several environmental and social variables, as shown in classification and regression analyses. Overall patterns indicated that forest use and cultural values are highest among people on Borneo who live close to remaining forest, and especially among older Christian residents.

Acoustic variability and individual distinctiveness in the vocal repertoire of red-capped mangabeys (Cercocebus torquatus).

Acoustic variability and individual distinctiveness of vocal signals are expected to vary with both their communicative function and the need for individual recognition during social interactions. So far, few attempts have been made to comparatively study these features across the different call types within a species' vocal repertoire. We collected recordings of the six most common call types from 14 red-capped mangabeys (Cercocebus torquatus) to assess intra- and interindividual acoustic variability, using a range of temporal and frequency parameters.

Sex differences in the vocal repertoire of adult red-capped mangabeys (Cercocebus torquatus): A multi-level acoustic analysis.

Sex differences in the vocal behavior of nonhuman primates can take various forms: sex-specific call types, differential production of shared call types, or sex discrepancy in phonation. Also, a growing literature is evidencing that systematically analyzing the vocal repertoires of primates at the call level might lead to underestimating their communicative abilities. Here, we present an extensive multi-level analysis of the still unknown vocal repertoire of adult red-capped mangabeys (Cercocebus torquatus), with a special emphasis on sex differences.