Primate communication is a popular research topic in anthropology and other subjects. Current research indicates that non-human primates are able to utilize gestural, vocal, and chemical signals to convey messages. In most animals, communication involves instinctive reactions to various stimuli. In other words, communication in most animals involves involuntary behavioral reactions. In non-human primates, however, communication involves a complex cognitive process. As such, communication among these primates indicates flexible behavioral adaptations. Non-human primates have the ability to communicate via gestures and vocal communication. For instance, non-human primates often engage vocalization to one each other of imminent danger such as presence of a predator. This paper presents a critical evaluation of primate communication.
Evidence available indicates that black howler monkeys use both vocal and gestural communication. Briseño-Jaramillo, Estrada, and Lemasson (2015) conducted a study investigating the communication behavior of black howler monkeys. The study revealed that majority of the black howler monkeys in the Palenque National Park region typically places a hand over their mouth while vocalizing. Interestingly, the researchers did not observe this vocalization behavior in black howler monkeys living in the distant Yucatan region (Briseño-Jaramillo, Estrada, & Lemasson, 2015, p.3). Further, the study revealed that black howler monkeys are able to identify individual acoustics. Laidre (2011, p.1) finds significant evidence that mandrills are able to develop shared meanings. The study findings indicate that mandrills found in Colchester, England express a common gesture by covering their eyes and lifting an elbow higher in the air. The mandrills use the ‘eye covering’ gesture as a warning sign to others against disturbance or interruptions (Laidre, 2011, p.2). This indicates shared meanings of the gesture.
The ‘eye covering’ gesture among mandrills is specific and unique to these primates only. The study compared the primates’ behavior in various parts of the world including Europe, Africa, and America (Laidre, 2011, p.1). While all mandrills in the various parts of the world express certain common features in communication such as similar body movements and facial expressions, the mandrills of England were unique with regard to the eye covering gesture (Laidre, 2011, p.6). The gesture seems to have developed on its own without the intervention of humans. Research focusing on chimpanzees has produced significant findings on their communication behavior. Gruber and Zuberbuhler (2013, p.1) conducted a study analyzing joint travel in chimpanzees. The findings reveal that chimpanzees use a unique way of vocalization while engaging in joint travel.
Chimpanzees use ‘travel hoo’ vocalizations when engaging in joint travel. According to Gruber and Zuberbuhler (2013), chimpanzees apply ‘travel hoo’ vocalizations during joint travel activities only. The findings indicate that during joint travel, chimpanzees produce a unique vocalization not common in other contexts. The chimpanzees conduct travel initiations by making the vocalization along with certain gestures, mainly “waiting and checking” (Guber & Zuberbuhler, 2013, p.2). The leader normally produces the ‘travel hoo’ vocalization, while waiting and checking to see the behavioral responses of other chimpanzees. Such vocalizations indicate the development of shared meanings among the chimpanzees. The development of shared meanings is similar to the case of mandrills that also share similar meanings (Laidre, 2011, p.1). According to Guber and Zuberbuhler (2013, p. 7), the vocalizations and gestures are an indication of intentional communication.
An interesting concept in primal communication is voice recognition. According to Briseño-Jaramillo, Estrada, and Lemasson (2015b, p.1), black howler monkeys are able to differentiate the voice of other black howler monkeys from different groups. Voice recognition is a significant step in the enhancing the social life of animals since it enables the animals to identify their close members or those that they share mutual bonds. Black howler monkeys are able to recognize individual acoustic signatures by various monkeys (Briseño-Jaramillo, Estrada, & Lemasson, 2015). Further, black howler monkeys are able to discriminate between group members and the non-group members by listening to the specific acoustic variations (Briseño-Jaramillo, Estrada, & Lemasson, 2015b, p. 22). This is great indication about primate communication potential.
Primate communication seems to vary across primate groups rather than among primate species. For instance, the hand-front-mouth gesture among black howler monkeys was limited to particular subsets of the population studied (Briseño-Jaramillo, Estrada, & Lemasson, 2015). In the case of the black howler monkeys, the hand-front-mouth behavior was evident among a particular age segment, rather than across the entire subgroups. This indicates that hand-front-mouth gesture was a learned behavior. Researchers first observed the eye-covering gesture in a 3-year old mandrill, ‘Milly’, in 1999 (Laidre, 2011, p. 2). This behavior was unique among the community of mandrills in the Colchester Zoo. Other mandrills, although not related to Milly, adopted the gesture, which has stuck up to date. This indicates intentional primate communication.
Briseño-Jaramillo, M., Estrada, A., & Lemasson, A. (2015). Behavioural innovation and cultural transmission of communication signal in black howler monkeys. Scientific Reports, 5(1), 13400. doi:10.1038/srep13400
Briseño-Jaramillo, M., Estrada, A., & Lemasson, A. (2015b). Individual voice recognition and an auditory map of neighbours in free-ranging black howler monkeys (alouatta pigra). Behavioral Ecology and Sociobiology, 69(1), 13-25. doi:10.1007/s00265-014-1813-9
Gruber, T., & Zuberbühler, K. (2013). Vocal recruitment for joint travel in wild chimpanzees: E76073. PLoS One, 8(9) doi:10.1371/journal.pone.0076073
Laidre, M. E. (2011). Meaningful gesture in monkeys? investigating whether mandrills create social culture. PLoS One, 6(2) doi:http://dx.doi.org.ezproxy.liberty.edu/10.1371/journal.pone.0014610