Human Communication

Origins, Mechanism, and Functions

Maria D. Sera, Melissa Koenig, Maria D. Sera, Melissa Koenig

• Editore: Wiley
• Anno: 2021
• ISBN:
  9781119684312
• Edizione: 1
• Argomento: Psicología
• Categoria: Psicología del desarrollo

Cutting edge scholarship on the origins and functions of human communication In Volume 40 of Human Communication: Origins, Mechanism, and Functions, a distinguished team of editors delivers the latest scholarship to researchers, students, and practitioners interested in and working in the field of human communication. This vital resource explores the phylogenetic and ontogenetic origins, as well as the functions, of human communication. It will earn a place in the libraries of developmental psychologists, researchers and professionals dealing with speech, as well as a wide range of other academics and practitioners in language-related fields.

PART I
Phylogenetic Origins

CHAPTER 1
A Very Long Look Back at Language Development: Exploring the Evolutionary Origins of Human Language

CATHERINE HOBAITER

SCHOOL OF PSYCHOLOGY AND NEUROSCIENCE, UNIVERSITY OF ST. ANDREWS, ST. MARY’S COLLEGE, SOUTH STREET, ST. ANDREWS, KY16 9JP, SCOTLAND

CAN WE SAY ANYTHING MEANINGFUL ABOUT LANGUAGE EVOLUTION BY LOOKING AT MODERN APE BEHAVIOR?

I have always been reluctant to use the lens of modern ape behavior to explore ideas about early hominid communication. Modern ape species are of interest in their own right, not simply as a scaffold to understanding our own evolution, and their rich repertoire of behavior is an ever-present check on any grandiose ideas we might acquire of our own importance. More importantly, by adopting an anthropocentric perspective that focuses on comparisons to human language, we risk missing extraordinary non-human ape-specific capacities. Finally, it too often feels like the sort of speculation best suited to after-dinner conversations with a beer in hand. Languages don’t fossilize into concrete evidence that we can explore. The traces of adaptations for language use in our physiology, for example brain morphology and lateralization (Geschwind, 1970; Horwitz et al., 2003; for non-human apes see Cantalupo & Hopkins, 2001; but cf. Sherwood, Broadfield, Holloway, Gannon, & Hof, 2003) or the vocal and breathing structures (Fitch & Hauser, 1995; Ghazanfar & Rendall, 2008; Kay, Cartmill, & Balow, 1998; Lieberman, 1968; MacLarnon & Hewitt, 2004), provide only the barest of clues to the cognitive processes that are encapsulated in what was being communicated. And fundamentally that is what language – like any communication system – is about, not the repertoires of vocal sounds and physical actions, but the information it contains.

And yet it is so tantalizing! What was that first word or first sentence? Communication systems, like other behavior, are an adaptation to a species’ ecological niche (Cheney & Seyfarth, 2018); thus, each species has the system of communication it needs to achieve its goals. What did we need to communicate that took us beyond the systems of signals that other species employ today? Can we compare modern ape species’ communication, including our own, to try to trace possible patterns of evolutionary development?

THE APE TOOLKITS FOR COMMUNICATION

Great apes – human and non-human – communicate using a range of signals: vocalizations, gestures, facial expression, body posture, even olfactory and color cues, and – in the case of humans – spoken and signed language. Modern ape species share the majority of the tools available to produce these signals; we are able to produce a similar range of movements with our hands, bodies, and faces. In contrast, our vocal sound production seems to have diverged strikingly.

The seminal study exploring non-human apes’ capacity to acquire human language describes the case of a young female chimpanzee, Viki. Adopted and raised “as nearly as possible like a human child” from birth (Hayes & Hayes, 1951), Viki’s development showed many parallels with that of human children; however, critically, she failed to acquire speech. Even following the instigation of an intensive speech-training program at 5 months old, by the time she reached 3 years old she had only acquired three poorly vocalized “words” (mama, papa, cup), and by 6 years old had added only a single extra “word” (up; Hayes & Hayes, 1951; Hayes & Nissan, 1971). This failure to add to her vocal repertoire led the authors to describe language as “the one field of behaviour in which we have thus far been able to find a large, clear-cut, and important superiority of man over chimpanzee” (Hayes & Hayes, 1951). However, to be fair, and despite impressive fine motor control of our vocal apparatus (Fitch & Hauser, 1995; Ghazanfar & Rendall, 2008), very few humans are capable of producing a convincing chimpanzee pant-hoot, bonobo peep, or orangutan long call. So, today, it may be more appropriate to say that primate vocalization is one of the many areas in which highly specialized species-specific behavior is not easily reproduced by species without the relevant physiological adaptations. An important point sometimes overlooked though is that Hayes and Hayes’ work did not provide evidence that Viki failed to acquire language; just that she failed to produce speech.

In contrast to the distinctions in our vocal production, all great apes – human and non-human – display manual dexterity and have a large and similar range of movements available in the shoulder, elbow, and wrist (Tanner & Byrne, 1999). This overlap, together with early reports on the use of gestural communication in wild chimpanzees (Goodall, 1968), led Gardner and Gardner to revisit the idea of language training with an ape, but using sign rather than speech. The Gardners adopted the female chimpanzee Washoe at around 1 year old and reared her in an environment where all communication was conducted with American Sign Language (ASL). The results were dramatic: Washoe acquired a large reliable set of ASL signs (30 within 22 months; 133 over her lifetime), and, at an early stage, appeared to combine them spontaneously (Gardner & Gardner, 1969; Gardner, Gardner, & Nichols, 1989) – although it remained unclear whether or not she did so to combine meanings. She went on to use these signs towards other chimpanzees, including her adopted son Loulis, who himself acquired a rich repertoire of signs directly from his mother and other ASL-trained chimpanzees (the researchers having carefully avoided signing in his presence; Fouts, Fouts, & Van Cantfort, 1989). While these apes cannot be said to have acquired sign language, the capacity to acquire a large repertoire of ASL signs and to use and possibly combine them in a meaningful fashion went on to be demonstrated in gorillas (Patterson, 1978; Patterson, Tanner, & Mayer, 1988) and orangutans (Miles, 1990; although cf. Terrace, Petitto, Sanders, & Bever, 1979; Umiker-Sebeok & Sebeok, 1981 for discussion of methodological flaws). Bonobos have shown a similar capacity to acquire, use, and combine a large number of signs when employing a keyboard of lexigrams (Savage-Rumbaugh, McDonald, Sevcik, Hopkins, & Rubert, 1986; Savage-Rumbaugh, Rumbaugh, & McDonald, 1985). One indication that these studies were successful in revealing apes’ capacity for a very human-like behavior is that the understanding we gained through them contributed to the fact that we no longer consider it ethical to conduct them. The separation of infant apes from their natural families and peer group and enculturation into a human environment, whether for research or “entertainment,” results in irreversible harm to the individual apes (Freeman & Ross, 2014), and images of them in “human” contexts or in human contact have a significant negative impact on species conservation in the wild (Leighty et al., 2015; Ross, Vreeman, & Lonsdorf, 2011; Schroepfer, Rosati, Chartrand, & Hare, 2011). However, non-human apes’ (hereafter apes) capacity for language-like use of signs reinvigorated interest in their natural communication.

Gesture

The natural gestural repertoires of great apes are extremely large, with over 80 distinct signals in species repertoires, with substantial overlap across species (Byrne et al., 2017; Genty, Breuer, Hobaiter, & Byrne, 2009; Graham, Furuichi, & Byrne, 2017; Hobaiter & Byrne, 2011a; Schneider, Call, & Liebal, 2012), including our own. A recent study found that human infants between 1 and 2 years old, on the cusp of acquiring language, but without an established vocabulary with which to communicate their goals, also employ these “ape” gestures (Kersken, Gómez, Liszkowski, Soldati, & Hobaiter, 2019). Apes produce sequences of gestures (Fröhlich et al., 2016; Genty et al., 2009; Hobaiter & Byrne, 2011b; Liebal, Call, & Tomasello, 2004b; McCarthy, Jensvold, & Fouts, 2012), and deploy them to achieve everyday goals (Graham, Hobaiter, Ounsley, Furuichi, & Byrne, 2018; Hobaiter & Byrne, 2014). These “repertoires” may seem small in comparison to any human language, but human languages are also built on a relatively small set of shared phonemes (Lenneberg, 1968; Werker & Tees, 1984). And gestural repertoires could be much (much!) larger. We recently explored the repertoire of potential gesture types given the range of possible move...