Sahamalaza Sportive Lemur, Lepilemur sahamalaza, Vocal Communication: Call Use, Context and Gradation

Abstract

Stereotypical vocalisations can facilitate long-distance communication in dense and, thus, sound-degrading forest habitats. Despite this, primate vocal repertoires often also include gradations between different call types that are used in social interactions. Because many nocturnal primates show a solitary social structure, it has been difficult to assess the role vocalisations play in mediating their social encounters. Here we aim to expand on the call types of Sahamalaza sportive lemurs, Lepilemur sahamalaza, as well as investigate their variability and use in social contexts. Through long-term behavioural observations with concurrent recording of vocalisations of known and unknown individuals between 2015 and 2016, we described three previously unrecorded calls and expanded the vocal repertoire to 12 different call types that were used in both targeted social and broadcast solitary contexts. Linear discriminant function and cluster analysis supported initial observations that vocalisations within call types were variable and that at least two call types can be classified as "graded," contrary to expectations. Despite variations in call-context connections, no clear patterns of call use could be established. However, measurable differences in vocal behaviour between the seasons and the sexes indicate that calling is used in a reproductive context, similar to other nocturnal and diurnal primates.

Chimpanzees produce diverse vocal sequences with ordered and recombinatorial properties

“…We conducted a literature search on vocal sequences production in non-human primates (see details in the method section). We found reports of vocal sequence production in 31 non-human primate species and in all the four major taxa (i.e., apes and old-world monkeys (catarrhini): agile gibbons, Hylobates agilis 55 , chimpanzees (our study), bonobos, Pan paniscus 56 , 57 , gorillas, Gorilla gorilla 58 , orang-utans, Pongo pygmaeus 59 , 60 , blue monkeys, Cercopithecus mitis 61 , Campbell’s monkeys, C. campbelli 62 , chacma baboon, Papio ursinus 27 , DeBrazza’s monkeys, C. neglectus 62 , Diana monkeys, C. diana 63 , geladas, Theropitecus gelada 64 , olive baboons, P. anubis 27 , putty-nosed monkeys, C. nictitans 22 , 65 , red-capped mangabeys, Cercocebus torquatus 62 , sooty mangabeys, Cercocebus torquatus atys 66 , Thomas langurs, Presbytis thomasi 67 , white-handed gibbons, H. lar ; new-world monkeys (platyrrhini): golden lion tamarins, Leonthopitecus rosalia 68 , common marmosets, Callithrix jacchus 69 , Goeldi’s marmosets, Callimico goeldii 70 , pygmy marmosets, Cebuella pygmaea 71 , silvery marmosets, Mico argentatus 72 ; and prosimians (haplorrhini): Philippine tarsiers, Tarsius syrichta 73 , common brown lemurs, Eulemur fulvus 74 , indris, Indri indri 29 , giant mouse lemurs, Mirza mirza 75 , red-bellied lemurs, Eulemur ribriventer 74 , crowned lemurs, E. coronatus 74 , mangoose lemur, E. mangoz 76 , Sahamalaza sportive lemur, Lepilemur sahamalensis 77 ). At least one species of each of these taxa produced sequences comprising at least three different vocal units.…”

Main functions of loud vocalization in populations of edible dormouse Glis glis

“…(Blumstein & Armitage 1997, Matrosova et al 2012, yellow-bellied glider (Petaurus australis) (Goldingay 1994) and others. Loud signals are often found in primates (Zimmermann 1995, for which several of their functions are postulated, including those related to alerting, coordination of group behaviour, attracting a reproductive partner, defence of infants and mates, and defence of resources (Oliveira & Ades 2004, van Belle et al 2014, Sperber et al 2017, Mandl et al 2019. The carrying distance of loud calls emitted in primates, mainly by males, is positively correlated with the size of the home range, which indicates their essential role in attracting mates and defending mates and resources (Wilch & Nunn 2002).…”