Running head: ANIMAL LANGUAGE

Real-life Planet of the Apes:

The Existence of Animal Language

Emily DeCoster

University of Evansville

Abstract

The issue of animal language has long been debated, especially with respect to primates who are humans' closest relatives. There is only one way to answer this question: design a situation where apes can prove, once and for all, whether they have the capacity for language. By teaching 600 apes American Sign Language (ASL) and then releasing them into the wild, they will be given the chance to develop their own pidgin language. If observed 50 years later, this language should have its own grammar and abstract, complex words and symbols.

Introduction

The existence of language in animals has long been debated. Obviously, animals will not be able to speak exactly as humans do because they lack the same physiological structures. However, the capacity for language may exist in them, especially in higher-order primates that are very similar to humans. This topic will be explored further, culminating in an experiment which may very well settle this dispute.

Definition of Language

Before deciding if animals have language, one must first define language itself. Although everyone seems to know what it is, an exact definition is elusive. It is more than just communication, obviously. It can be defined as the "use of an organized means of combining words in order to communicate" (Pritchard, 2003). This has problems, however, in that it does not specify what language is and is not.

Charles Hockett (1958) tried to solve this problem by developing nine properties of language that can differentiate between "true" language and what may be simply communication systems. There are three properties that all the latter have: a mode of communication (some way of transferring the message), semanticity (the signals have meaning), and pragmatic function (the system of communication serves some purpose for those using it).

Furthermore, some communication systems have the following five properties: interchangeability (the ability for each organism to send and receive messages), cultural transmission (the communication is not genetically innate and must therefore be passed from parent to child), arbitrariness (the signals take forms not logically related to their meaning), and discreteness (complex messages are built up from small parts that can be combined in different ways). True language, as proposed by Hockett, has in addition these last two features: displacement (ability to convey things that are not present in space or time) and productivity (the ability to produce new messages that have never before been expressed).

These language properties have one major flaw, mainly that they were developed roughly 40 years ago before primate research really took off. This current research will try to address this and show that a sign language developed by apes, and used as their primary means of communication, will indeed exhibit all of Hockett's properties.

Another flaw with Hockett is the lack of focus on comprehension. When learning a foreign language, this is often easier to gain than the ability to respond in kind. Additionally, mute children without the ability to speak can still understand what is said to them, even though they may not be able to respond. Although primates may not respond with all the complexities found in human language, the fact that their signs and responses are consistent is very significant. The capacity for language exists; the extent of this capacity must be found.

Another argument to Hockett is proposed by Premack (1986), who asks the question of what language really is. Human language, he points out, is not exclusively a communication system. Additionally, structure and function can both be emphasized as a way to define language, although the ideal theory would include both. He believes that ape speech can have both, while taking a quantitative approach. If sign language can function as a means of communication for apes, then one must be open to the possibility that it meets the threshold of being a language, especially when taking into consideration the physiological differences between humans and primates.

Physiological Differences

A large part of human language is vocal. Obviously, animals will have a problem with this part of language because they are incapable of making the sounds required for human speech. This is evident by comparing plaster casts made of various skulls, from chimps to Neanderthals to modern humans. Based on the position of organs such as the epiglottis and tongue, and the shape of the pharynx, modern human speech is impossible for primates, as well as Neanderthal man (Miner, 2003). However, Neanderthals still are considered to have had speech, only in a limited form. It may be possible to argue that primates, too, can have language, despite being unable to speak.

Another relevant physiological difference that must be considered when comparing humans and primates is the size and structure of the brain. Human brains are much larger and more developed than those of any other ape (Aiello & Dunbar, 1993). Although ape brains possess many similarities to human brains, such as parts of Broca's area, they are smaller with less sulci and furrows in the cortex (Cantalupo & Hopkins, 2001). They may also have slightly different uses, such as that area being used for motor skills as well as vocalization.

Additionally, brain complexity can be used to measure the differences between animal brains (Rumbaugh, 1995). This is calculated by the "extra" space in the brain, beyond what is needed for basic involuntary functioning, such as breathing. Primates such as apes have far more extra room to devote to memory, communication, and learning than do smaller primates and nonprimates. However, they do not have as much as humans do. Therefore, of all the animals, apes have the capacity for language usage, possibly meeting all the criteria of Hockett.

Language Usage in Apes

There are many case studies of apes with the ability to use human language. De Waal and Lanting (1997) discuss several apes who communicate using American Sign Language, including a bonobo named Kanzi. When he was little, he learned a sizable vocabulary of keyboard symbols while observing the practice sessions of his adopted mother. According to someone who studies him intensely, he can make sentences of two or three utterances where the order shows some regularity. The authors point out that this could be considered grammar.

Even more impressive is Kanzi's understanding of spoken English. When he is listening to headphones in a separate room, he can point to a picture of a cat or a melon when instructed to do so. He is also able to connect several ideas. For example, if someone says, "'Give the dog a shot,' he picks up a hypodermic syringe from among many objects on the floor, tears off the cap, and injects his stuffed toy dog" (p. 46).

The ape's trainer, Sue Savage-Rumbaugh, believes that this is truly language. She says,

Comprehension is the essence of language, and is far more difficult to explain and to achieve than production. Comprehension demands an active intellectual process of listening to another party while trying to figure out, from a short burst of sounds, the other's meaning and intent - both of which are always imperfectly conveyed. Production, by contrast, is simple… We don't have to figure out 'what it is we mean,' only how to say it (p 46).

Kanzi is just one of several apes with this ability to communicate with humans. Koko the gorilla is a famous example of an ape learning sign language, as well as the case of a mother learning the language and then teaching it to her infant. These examples, when combined with numerous others carried out by the Premacks such as Washoe and at facilities such as the Yerkes Regional Primate Research Center at Emory University, GA, demonstrate the capacity of chimps for language (Rosinsky, 2001). The only question at this point should be how large this capacity really is. This experiment has been designed to answer this question once and for all.

Hypothesis

The hypothesis is that apes, if given a chance, will develop their own language, much like the Nicaraguan students who over time developed their own sign language. Additionally, the degree of similarity with humans will predict the ability to develop the language, with bonobos showing the best results, followed by chimps, then gorillas, and finally spider monkeys, who will probably have little to no language development.

Methods

Participants

Participants include 600 primates divided into 4 groups of 150 each. One group would include bonobo apes, the second chimpanzees, the third gorillas, and the last a new world monkey such as a spider monkey. Each group would have 50 males and 100 females. At the start of the study, each primate will be young enough to learn a language, while later, when released, it will be able to take care of itself in the wild.

Participants also include researchers fluent in ASL to teach the primates how to sign. Each group of primates is further divided into groups of roughly 5-10, with each of the researchers responsible for teaching a group. Each researcher will have the same guidelines to follow so that each group learns basically the same things. All the groups will be combined by species, so any differences between teachers will be insignificant.

Procedures

After the primates know the language, probably after 2-3 years of intense daily instruction, they will be taken to a protected forest preserve in central Africa, as close to their natural habitat as possible. Each species group will have their own area, completely separate from those of the other groups. The area will be completely closed off to any outside influences for 50 years. Since the lifespan of each type varies, this time period should allow for at least several generations to be born and live their lives completely without human contact.

Meanwhile, researchers will continue to teach captive apes ASL. After 50 years, the researchers will establish contact with the wild apes and observe the language of each group. This will be determined by the following criteria: 1) the abstractness of the signs: does "hungry" or "eat" involve merely pointing to the mouth? 2) the frequency of the signs: does signing occur constantly or is it sporadic? 3) the consistency of the signs: is the same gesture always used to convey the same meaning? and 4) the importance of signing to each group: is it the only means of communication or is it used to compliment vocal communications?

At this point, the new apes will be brought in to the preserve. As they will know the same sign language as the researchers, they can act as translators between the two. Hopefully, they will be able to learn the newly developed primate sign language and communicate the meaning of the signs to the humans. This will allow the researchers to determine what means what and to evaluate each language on the above criteria.

References

Aiello, L. C., & Dunbar, R. I. M. (1993). Neocortex size, group size, and the evolution of language. Current Anthropology, 34, p 184-194.

Cantalupo, C., & Hopkins, W. D. (2001). Asymmetric Broca's area in great apes. Nature, 414, p 505.

De Waal, F., & Lanting, F. (1997). Bonobo: The forgotten ape. Los Angeles: University of California Press.

Hockett, C. (1958). Quoted in Clark, V. P., Eschholz, P. A., & Rosa, A. F. (eds., 1998). Language: Readings in Language and Culture (6 ed). Boston/New York: Bedford/St.

Miner, H. (2003). Personal communication, October 2nd, 2003.

Premack, D. (1986). Gavagai! Or the future history of the animal language controversy. Cambridge, MA: the MIT Press.

Pritchard, M. (2003). Personal communication, November 4th, 2003.

Rosinsky, N. M. (2001). "Going ape" over language. Odyssey, 10, p 10-12.

Rumbaugh, D. (1995). Primate language and cognition: Common ground. Social Research, 62, 711-730.