Functions of Wild Gorilla 'Close' Calls. I. Repertoire, Context, and Interspecific Comparison

  title={Functions of Wild Gorilla 'Close' Calls. I. Repertoire, Context, and Interspecific Comparison},
  author={Alexander H. Harcourt and Kelly J. Stewart and Marc D. Hauser},
Individuals in social groups of a number of species produce and exchange among themselves frequent, quiet vocalisations. The function of most such vocalisations, here termed 'close' calls, remains obscure, because of the lack of any obvious context of behaviour associated with their production. In this first of two papers that attempt to determine the function of these calls in wild girilla groups, we describe the call repertoire, the age-sex distribution of frequencies of call-types, the… 

Function and Meaning of Wild Gorilla 'Close' Calls

We investigate the social significance of the within group ('close') calls of gorillas by examining correlates of calling with dominance rank and with relatedness of adults, and by examining whether

Western Gorilla Vocal Repertoire and Contextual Use of Vocalizations

This study suggests that although vocal production is highly constrained by morphology and phylogeny, differing social and ecological conditions can yield differences in the use and function of calls, even between two closely related species such as western and mountain gorillas.

The function of loud calls (Hoot Series) in wild western gorillas (Gorilla gorilla).

Following hooting, the distance between separated group members decreased significantly; thus it is concluded that western gorillas use this call to reestablish group cohesion, demonstrating that the function and usage of particular calls can be flexible.

Social Basis of Vocal Interactions in Western Lowland Gorillas (Gorilla g. gorilla)

The results show that some apes use rule-governed call exchanges and that these socially guided vocal interactions are more widespread than previously believed.

Individual Distinctiveness in Call Types of Wild Western Female Gorillas

Discriminant function analyses confirmed that all call types were individually distinct, suggesting that neither the distance at which communication occurs nor the call social function alone can explain the evolution of identity signaling in western gorilla communication.

Production of Loud and Quiet Calls in Howler Monkeys

It is shown how the anatomy of howler monkey’s vocal organs can explain the unusual features of their loud calls and possibly the variation found between species, while also pointing to the various gaps that exist in the authors' knowledge regarding the role of the several components of their highly specialized vocal apparatus.

Loud Calls in Great Apes: Sex Differences and Social Correlates

If one were to scan the literature on primate behavior accumulated during the last two decades, one single taxon, the great apes, would likely dominate. Switching the key word to “communication”

Food-Associated Calling in Gorillas (Gorilla g. gorilla) in the Wild

The vocal behavior of two free-ranging groups of western lowland gorillas at Mondika, Republic of Congo is investigated and compared, providing new insight into the vocal abilities of gorillas and larger implications for questions concerning vocal variability among the great apes.

Evolution of Acoustic Communication Signals of Mammals: Friendly Close-Range Vocalizations in Felidae (Carnivora)

The distribution of the three friendly close-range vocalization types known in the Felidae was plotted on a recently published phylogeny based on sequence comparisons of two mitochondrial DNA genes and other molecular and biochemical characters, and it was found to be congruent with this phylogeny.

Preliminary Vocal Repertoire and Vocal Communication of Wild Bonobos (Pan paniscus) at Lilungu (Democratic Republic of Congo)

The aim of this study is to give a preliminary description of the vocal repertoire and a qualitative account of the contextual use of the voices described, which is compared to that of captive bonobos described by De Waal.



The Communicative Repertoire of Captive Bonobos (Pan Paniscus), Compared To That of Chimpanzees

The study shows that, while the behavioral repertoires of the two Pan species are fundamentally similar, interesting differences exist in their vocal repertoires, sexual behavior, and agonistic behavior.

The Evolution of Nonhuman Primate Vocalizations: Effects of Phylogeny, Body Weight, and Social Context

  • M. Hauser
  • Psychology, Biology
    The American Naturalist
  • 1993
The nonhuman primate data provide only partial support for S.E. Morton's motivational state-frequency rules, and features of the species-typical habitat have had direct selective effects on signal structure, optimizing for effective propagation through the environment.

The acoustic features of vervet monkey grunts.

East African vervet monkeys give short (125 ms), harsh-sounding grunts to each other in a variety of social situations: when approaching a dominant or subordinate member of their group, when moving

Functions of alliances in contests within wild gorilla groups

Primates frequently support other individuals in aggressive contests among group members. Several functions of such alliances have been suggested, some of them dependent on continued residence of

An Analysis of Toque Macaque Cohesion Calls from an Ecological Perspective

The manner in which individuals in social groups space themselves in relation to each other and to other groups partly reflects how they might share limiting resources with one another, select their

On the evolution of Ape Social Systems

Despite theoretical advances in understanding the nature of social evolution (e.g. Hamilton, 1964; Trivers, 1972) a clear procedure for analysing the adaptive functions of social life has not yet