Primates communicate in several ways including gestures, facial expressions, gaze following, vocalizations, and smell. Many primates use vocalizations to communicate, with different calls serving functions like warning of predators, announcing food sources, or maintaining group cohesion. Primate vocalizations depend on both the sound source in the larynx and filtering by the vocal tract shape. Different primate species have evolved specialized forms of communication like gibbon songs that involve complex duets between mated pairs. Vervet monkeys use distinct alarm calls to warn of different predators like snakes, big cats, or birds of prey.

1. Forms and meaning of primate communication Presenter: RoyaShariati ANU College of Archaeology and Anthropology Supervisor: Prof. Colin Groves

2. What is Communication? Communication is the transfer of information from one Primate to another. The message or signal is passed between a sender and a receiver. The ability to detect and respond to stimuli is essential for survival. By detecting changes in the external environment, humans and other animals are able to respond appropriately.

3. Pictures from science daily web and wikipidia Form Of Communication Gestures Facial Expression Gaze Following Vocalization Olfactory communication Electro Communication Pictures from Sciencedaily website and Wikipedia

4. Many of primates communicate through vocalizations. Primate communication also involves mental representation in some cases, most clearly in the representational vocalizations used by primate species. Vocalization are believed to serve a variety of functions, including territorial advertisement; intergroup intimidation and spacing; announcing the precise locality of specific individuals, food sources, or danger; and strengthening intragroup cohesion. Vocalization:

5. Vocal organs (Chiba & Kiiama 1940) • Non-human primates have vocal organs similar to ours, but – the size of their tongue relative to the size of the mouth is much larger – their pharynx (area between the larynx and the mouth) is shorter

6. Primate vocalizations Both non-human primates and humans use the larynx for the source of sound production and the oral cavity above the larynx as the filter. Kratzenstein‘s geometric-acoustic considerations based on reflections within elliptical cones (Gessinger 1994) Non-human primates have much larger tongue: not advantageous in manipulating the shape of the vocal tract. Non-human primates have shorter pharynx: less room to play with the shape of the vocal tract. – But they have lower risk of choking on food

7. Source-filter theoryThe source-filter theory describes speech production as a two stage process involving the generation of a sound source, with its own spectral shape and spectral fine structure, which is then shaped or filtered by the resonant properties of the vocal tract. The vowel, its nature and structure / by Tsutomu Chiba and Masato Kajiyama 1941

8. Source-filter theory: illustration

9. Source filter theory and vocalization • So what a vocalization sounds like depends on what the sound source is like and how that source is filtered • The source can be created by vibrating the vocal folds in the larynx – How fast the vocal folds vibrate will determine the fundamental frequency of the sound • The shape of the vocal tract above the larynx determines the nature of the filter – which frequencies are amplified and which are attenuated – One can make sounds of equal pitch but different quality (timbre)

10. Barks and pant-threats Lips are slightly protruded and maximally spread apart at the beginning of each sound – The lower jaw, or the mandible drops to the lowest point – This is more prominent for barks than for pant-threats – The teeth are partially separated during the production Barks are more likely to be associated with physical aggression

11. Noisy and undulating screams Produced by individuals being threatened by a dominant member of the group – Noisy screams are more consistently associated with physical attack than undulating screams The lips are retracted, revealing the teeth – Lip retraction appears more prominent for noisy scream than for undulating scream

12. Coos and grunts Coos and grunts are produced during group movement, affiliative activities, and when one approaches another to groom When producing coos, the lips are separated fairly wide and somewhat protruded while the mandible is lowered When producing grunts, lips are separated, often to a negligible degree, and there is no lip protrusion

13. links • Rhesus monkey calls http://www.wjh.harvard.edu/~mnkylab/media/rhesuscalls.html http://www.soundboard.com/sb/Rhesus_Monkey_sounds.aspx • Rhesus monkey articulation – Hauser et al. (1993). The role of articulation in the production of rhesus monkey, Macacamulatta, vocalizations. Anim. Behav., 45, 423-433. http://galliform.psy.mq.edu.au/Reprints/Hauser_Evans&Marler_1993.pdf – Lieberman et al. (1980). Vocal tract limitations on the vowel repertoires of rhesus monkey and other nonhuman primates, Science, 164, 1185-1187. http://web.haskins.yale.edu/Reprints/HL0080.pdf

14. Call Context Food Many primates produce distinct calls when discovering or eating food. Predators Many primates produce alarm calls in response to predator (Cheney and Seyfarth, 1990), Mating In most of species both sexes produce copulation calls (Hauser, 1996) Caller Identity Individual Sex Group membership

15. Rhesus food discovery vocalizations When rhesus macaques discover food, they call out, at which point other group members come running Hauser (1996) catalogued five different food calls – ‘warbles’, ‘chirps’, and ‘harmonic arches’ are associated with rare and high-quality foods (e.g. coconut) – ‘coos’ and ‘grunts’ are for common, low-quality foods ‘Silent discoverers’ who are caught with food are severely beaten up, and this is true for high and low ranking individuals Males make food calls less often than females

16. Food calls are intentional, not reflexive When individuals discover food, they first scan the area, looking for enemies and/or allies Members of social groups have different calling behaviours than males who live peripherally, waiting to join a social group – When peripheral males find food, they never call – These peripheral silent discoverers never receive targeted aggression These observations suggest that rhesus macaques can intentionally withhold information about food discoveries

17. Rhesus mating vocalizations • Males produce extremely loud and individually distinctive screams during mating • Hauser (1996) found that males who call during copulation obtain significantly more mating than males who were silent • However, vocal males also received significantly more aggression than did silent males • This suggests there are potential survival costs to calling (natural selection pressure), but potential reproductive benefits (sexual selection pressure)

18. Gibbon songs Gibbons, unique among non-human primates, produce complex songs in order to attract mates, advertise pair bonds (duets), repel introducers, and warn each other of predators http://www.gibbons.de/main/sound/sounds/07hool_sounds/hoDuett88a2027.wav

19. Gibbons (Hylobates spp.) produce loud and long song bouts that are mostly exhibited by mated pairs. Typically, mates combine their partly sex-specific repetoire in relatively rigid, precisely timed, and complex vocal interactions to produce well-patterned duets. A cross-species comparison reveals that singing behaviour evolved several times independently in the order of primates. Most likely, loud calls were the substrate from which singing evolved in each line. (Geissmann, T., 2000). Singing male white-handed gibbon (Hylobateslar, Zoo Rapperswil)

20. Another specialization is the occurrence of duet singing in all gibbons with the exception of H. klossii and H. moloch (Geissmann 1993). Duets are mostly sung by mated pairs . Typically, mates combine their repertoire in relatively rigid, more or less precisely timed vocal interactions to produce well-patterned duets.http://www.gibbons.de/main/sound/sounds/08conc_sounds/coDuett94b3270.wav

21. Vervet monkeys

22. Vervet monkey alarm calls • Vervet monkeys produce acoustically distinct alarm calls in response to different classes of predator – Large cats (e.g. leopard, cheetah) – Birds of prey (e.g. martial eagle, crowned hawk eagle) – Snakes (e.g. pythons, mambas) • Hearing the leopard call, the members of the troupe run up to the top of the nearest tree • Hearing the eagle call, the members of the troupe run into a nearby bush or under the lower branches of a nearby tree • Hearing the snake call, the troupe of vervets all stand up on their hind legs in the open and look around on the ground

23. Conclusion: communicate with a group. Animal communication is more based on the need to warn of danger or to describe the location of food, it is more of a necessary means of survival. Human language however adopts these characteristics of needing communication for survival but adds to them to form a language system that is both needed for survival but is also a social communication device, that is used spontaneously, something an animal does not especially require in order to survive in the animal world.(Tomasello and Call 1997).

24. Books Bradbury, J. W. & Vehrencamp, S. L. (1998) Principles of animal communication., Oxford, Blackwell Cheney, D. L. & Seyfarth, R. M. (1990) How monkeys see the world: Inside the mind of another species., Chicago, Chicago University Press Chiba, T. & Kajiyama, M. (1941). The Vowel, its Nature and Structure. Tokyo. Hauser, M. D. (1996) The evolution of communication., Cambridge, MIT Press Owings, D. H. & Morton, E. S. (1998) Animal vocal communication: A new approach, Cambridge, Cambridge University Press Articles in Books Dawkins, R. & Krebs, J. R. (1978) 'Animal signals: Information or manipulation' In Behavioural ecology (Krebs, J. R.&Davies, N. B., eds), pp Oxford University Press Fischer, J. (2002) 'Developmental modifications in the vocal behavior of non-human primates' In Primate audition: Ethology and neurobiology (Ghazanfar, A. A., ed), pp 109-125, CRC Press Marler, P., Evans, C. S. & Hauser, M. D. (1992) 'Animal signals? Reference, motivation or both?' In Nonverbal vocal communication: Comparative and developmental approaches. (Papoucek, H., Jürgens, U.&Papoucek, M., eds), pp 66-86, Cambridge University Press Owren, M. J. & Linker, C. D. (1995) 'Some analysis methods that may be useful to acoustic primatologists' In Current topics in primate vocal communication (Zimmermann, E., Newman, J. D.&Juergens, U., eds), pp 1-27, Plenum Press Snowdon, C. T. (1986) 'Vocal communication' In Comparative primate biology, vol. 2a, conservation and ecology (Mitchell, G.&Irwin, J., eds), pp 495-530, Alan R. Liss

25. Articles in Journals Cheney, D. L. & Seyfarth, R. M. (1980) Vocal recognition in free-ranging vervet monkeys. Animal Behaviour 28,362-367Crockford, C., Herbinger, I., Vigilant, L. & Boesch, C. (2004) Wild chimpanzees produce group-specific calls: A case for vocal learning? Ethology 110,221-243 Fichtel,C. & Kappeler, P.M. (2002) Anti-predator behavior of group-living Malagasy primates: mixed evidence for a referential alarm call system. Behavioral Ecology and Sociobiology, 51: 262-275. Fitch, W. T. (1997) Vocal tract length and formant frequency dispersion correlate with body size in rhesus macaques. Journal of the Acoustical Society of America 102,1213-1222 Fitch, W. T., Neubauer, J. & Herzel, H. (2002) Calls out of chaos: The adaptive significance of nonlinear phenomena in mammalian vocal production. Animal Behaviour 63,407-418 Gouzoules, H. & Gouzoules, S. (1990) Body size effects on the acoustic structure of pigtail macaque (macacanemestrina) screams. Ethology 85,324-334 Gouzoules, S., Gouzoules, H. & Marler, P. (1984) Rhesus monkey (macacamulatta) screams: Representational signalling in the recruitment of agonistic aid. Animal Behaviour 32,182-193 Gros-Louis, J. (2004) The function of food-associated calls in white-faced capuchin monkeys, cebuscapucinus, from the perspective of the signaller. Animal Behavior 67,431-440

26. Hamilton, W. J., III & Arrowood, P. C. (1978)Copulatory vocalisations of chacma baboons (papioursinus), gibbons (hylobateshoolock), and humans. Science 200,1405-1409 Marler, P. (1955) Characteristics of some animal calls. Nature 176,6-7 Marshall, A. J., Wrangham, R. W. & Clark, A. P. (1999) Does learning affect the structure of vocalizations in chimpanzees? Animal Behaviour 58,825-830 Miller, C. T., Scarl, J. S. & Hauser, M. D. (2004) Sex-specific sensory biases underlie sex differences in tamarin long call structure. Animal Behaviour 68:713-720. Mitani, J. & Gros-Louis, J. (1998) Chorusing and convergence in chimpanzees: Tests of three hypotheses. Behaviour 135,1041-1064 Rendall, D., Owren, M. J. & Rodman, P. S. (1998) The role of vocal tract filtering in identity cueing in rhesus monkey (macacamulatta) vocalizations. Journal of the Acoustic Society of America 103,602-614

27. Rendall, D., Owren, M. J., Weerts, E. & Hienz, R. D. (2004) Sex differences in the acoustic structure of vowel-like vocalizations in baboons and their perceptualdiscrimination by baboon listeners. Journal of the Acoustical Society of America 115,411-421 Semple, S. (1998) The function of barbary macaque copulation calls. Proceedings of the Royal Society, London 265,287-291 Semple, S. & McComb, K. (2000) Perception of female reproductive state from vocal cues in a mammal species. Proceedings of the Royal Society, London 267,707-712 Zahavi, A. (1975) Mate selection: A selection for a handicap. Journal of Theoretical Biology 53,205 214 Zuberbuhler, K., Cheney, D. L. & Seyfarth, R. M. (1999) Conceptual semantics in a nonhuman primate. Journal of Comparative Psychology 113,33-42 Zuberbuhler, K., Noe, R. & Seyfarth, R. M. (1997) Diana monkey long-distance calls: Messages for conspecifics and predators. Animal Behaviour 53,589-604