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LANGUAGE IN NON-HUMAN SPECIES
Sceptics consider it simpler to assume that humans are unique, andthat the burden of proof should be borne by anyone who thinksotherwise. Any claim of language-like elements for animals isconsidered a more complicated hypothesis, to be dismissed as
unnecessary in the absence of positive proof. Yet the alternative
hypotheses by which the sceptics instead attempt to explain animal
behaviour sometimes strike me as more complicated than the simple,
and often plausible, explanation that humans are not unique.
(Jared Diamond 1991:130)
Humans still have the old innate call system, existing alongside language. Sounds like
laughter and screams are controlled by the older neural (subcortical) structures in the
brain, which are also responsible for the call systems of other species. Some
non-human species appear to have a system of sounds which involve learning and
experience, existing alongside the innate call system.
Birdsong appears to have much in common with human language. Birds have an
innate system of calls, but their songs mostly involve learning and develop by later
experience (Aitchison 1996:7-9). Like babies experimentally babbling, young birds
have a period of sub-song before their songs are fully developed, and they also
appear to have a sensitive period in which they learn their songs. Some birds, e.g. the
bullfinch, can pick up the song of another species, just like children can learn any
language they are exposed to (Fromkin and Rodman 1998:344-345). Also, the song
of a single species of bird may have different dialects. Normally, the left
hemisphere of the brain controls both birdsong and human language.
The sound units of birdsong are strung together and fitted into intonational patterns
and rhythm. All languages have some type of speech melodies. Pitch plays an
important role in both human tone and intonation languages, but in different ways.
Tone languages, like Chinese, have contrasting pitches or tones, i.e. the same sound
will have different meanings depending on its pitch (Fromkin and Rodman
1998:241).
The African grey parrot ALEX, studied by Irene Pepperberg, imitates human
utterances and seems to relate these sounds with meanings, but his ability to imitate
sounds similar to those produced by humans is quite different from the acquisition of
syntax (Fromkin and Rodman 1998:23-24). Birds have syrinxes (Michelsen
1977:35-39), which indicates that some articulated speech is possible without a
larynx.
Studies of communication among whales are limited in scope, but their sounds seem
to be motivated by a need to communicate. As they vocalize under water, it is
difficult to investigate their communication systems, and many of their sounds are at
frequencies that humans cannot perceive.
Researchers have tried to teach dolphins forms of language, e.g. acoustic
computer-generated whistles in the water, but so far investigation has not revealed
whether they use their calls for any kind of human-like conversation (Lane and
Molyneaux 1992:128-130). The use of hydrophones has revealed that the creaking
sounds consist of a series of clicks, showing certain patterns which are unique to the
individuals producing them (Bonner 1980:121-122). Bottle-nosed dolphins have an
impressive auditory memory system, capacities for rule-governed behaviour, and for
imitative learning. Investigations of their whistles have revealed different patterns,
which have been identified by the pitch contour, e.g. downward glide = distress,
upward glide = search, rise-fall-rise-fall = excitement or irritation (Bonner
1980:128-129). Also, dolphins use vocalizations for echo-location (navigation, food
location, object identification, etc.).
Observations of humpbacks have revealed that they may have complex
communication systems utilizing all their senses to varying degrees (Bonner
1980:124).
Each song is made up of a constant number of themes repeated in
the same order. The themes are composed of phrases and the main
difference between successive songs of a particular whale is the
number of phrases in each theme. No theme is ever left out
completely, but sometimes a whale repeats a phrase many times
before going on to the next theme. Phrases may change gradually
through the course of a theme, so that a phrase at the end of a theme
may be quite different from what it was at the beginning.
Most likely, these intelligent marine mammals could be a threat to human
uniqueness.
Apes are our closest relatives in nature, and it is not surprising that they attract a
special attention. Many researchers have tried to teach apes to communicate with
humans and even with one another. The earliest experiments with chimpanzees
showed that they were not physically capable of producing articulated speech
(Wardhaugh 1993:43-45) although they did understand many spoken words. Other
methods were adopted in order to avoid the problems in trying to teach apes to
speak, and some of these attempts were remarkably successful. Some researchers
(R.A. and B.T. Gardner and H.S. Terrace) taught the apes American Sign Language
(ASL) as apes do not find it difficult to control their hands. Others have used
keyboards of symbols (D. and S. Rumbaugh) and plastic tokens (D. Premack)
varying in shape, size, texture, and colour representing words (Fromkin and Rodman
1998:350-355).
Many researchers have some general idea of the kind of results they want, and in the
ape-experiments there are some obvious contrasts in the ways the researchers treat
their subjects. Some seem biased in favour of apes acquiring language, others go
into the studies to prove that non-human primates cannot possibly learn language,
each side of the debate is determined to prove the other side wrong, but both sides
agree that these animals are communicating. Because of their opposite expectations
they disagree as to the extent of this communication.
The chimpanzee WASHOE (R.A. and B.T. Gardner) was taught a version of ASL
called Ameslan (Fouts and Mills 1997:87-110). She used combinations of signs
similar to the telegraphic speech that very young children use, and a gradual increase
in the length of her sign combinations was observed. She spontaneously combined
signs creating new words, she used wh-questions and prepositions, she associated
between arbitrary elements (manual signs) and concepts, she understood the
distinction between proper and common nouns, she organized words in a
classification system, and she was able to express her thoughts and needs and to talk
about the past, things not present, and places she could not see. Also she developed a
preference of word-order, in 90 percent of the utterances the word-order was: SVO.
Washoe thought of herself as human. When categorizing pictures of humans and
animals, she placed herself with humans and other chimpanzees with animals. She
actually taught other chimpanzees ASL-signs, and her infant LOULIS managed to
learn over 50 signs without being taught by humans, simply picking up the signs
from his mother and the other ASL-signing chimpanzees when they signed to each
other and to themselves. Washoes signs were more immature than those made by
the adult human deaf, but this may be due to the fact that she was not human, and
that her trainers were not experts in ASL themselves (Wardhaugh 1993:45-49).
However, some deaf children have been much impressed as they have been able to
talk with her.
Washoe was born wild in Africa and had already been exposed to her native
tongue. She was approximately one year old when the language-experiment started,
which means that she was learning a second language. Other apes have been older
when similar experiments started, some of them may even have passed the critical
age, a fact that must have influenced the results.
R.A. and B.T. Gardner and Roger Fouts have been very careful not to overinterpret
the results of their signing chimpanzees, and they have developed procedures in
order to test the knowledge and the reliability of the vocabulary of the apes as well
as preventing any possible non-verbal cueing. Also, they have taken great pains
making the apes feel comfortable, keeping them in a very free and stimulating
environment.
Comparison of the language of two-year-old children and chimpanzees:
Object-attribute:
Childs utterances: Big train. Red book.
Washoes utterances: Dink red. Comb black
Agent-object:
Childs utterances: Adam checker. Mommy lunch.
Washoes utterances: Clothes Mrs. G. You hat.
Action-location:
Childs utterances: Walk street. Go store.
Washoes utterances: Go in. Look out.
Agent-action:
Childs utterances: Adam put. Eve read.
Washoes utterances: Roger tickle. You drink
Action-object:
Childs utterances: Put book. Hit ball.
Washoes utterances: Tickle Washoe. Open blanket.
(Linden 1974:30-48, from R.A. and B.T. Gardner Two-way
communication with an infant chimpanzee in Behaviour of
Nonhuman Primates, eds. A. Schrier et al., New York: Academic
Press, 1971.)
There are many parallels between Washoes utterances and those of two-year-old
children, despite the fact that Washoe used ASL and the children spoken language.
A comparison between the utterances of ASL-signing chimpanzees and ASL-signing
children has not yet been undertaken.
Bickerton (1990:110-112) points out that we regard the utterances of the child as a
foretaste of adult language, because we know that the child within a few years will
construct a grammar based on the language it is exposed to, and as we know that the
ape will progress only to a limited extent, we conclude that it has no language.
Somehow children have the ability to reconstruct the kind of language they are
exposed to. Language develops over a period of years as the child interacts with
speaking or signing adults, and children reared in isolation do not acquire language
(Fromkin and Rodman 1998:343). All social mammals learn by imitating their
elders, and children also observe, imitate, and play. Bickerton argues that children
under two are not acquiring language but protolanguage and that the preference of
word order is just as much a characteristic of apes as it is of children under two.
These rules of word order are probably semantic structures preceding the syntactical
constructions.
Suppose that the neural infrastructure underlying formal syntax
crucially involves aspects of the brain that do not develop until after
birth and are not completed until the child is approximately two years
of age. It would then follow that, at the time a child gains enough
vocal control to imitate the utterances of elders (a time that may vary
from age twelve months to eighteen months in normal children) that
child is still incapable of syntactic language. Bickerton (1990:112)
The most obvious differences between the language of apes and humans are the size
of their vocabularies and the absence of grammatical items. Mostly the vocabulary
of apes has been limited to lexical items. However, Bickerton (1990:106-110) points
out that this may be due to the fact that the apes have not been taught grammatical
items. The researchers are not linguists, and as they have been making the
experiments for rather different reasons (e.g. the development of training procedures
for children who do not develop language normally and people who have language
difficulties caused by brain damage), quite naturally their interests have been
focused on other aspects of language, e.g. semantics.
Washoes trainers draw the conclusion that the chimpanzees capacity for language
is similar to that of a human child but may not be exactly the same (Wardhaugh
1993:48-49). The chimpanzees are born with language capacities that are perfectly
suited for gestural communication among groups of individuals in the jungle.
Human language share some of these origins, but it has become specialized for a
very different way of life in much larger communities
When comparing the ape-reports with the Hockett design features of language,
elements of all of the seven key-properties seem to occur. Washoe and the other
ASL-signing chimpanzees talked to one another (interchangeability), and the infant
Loulis learned 50 signs from the other chimpanzees as no sign language was used by
humans in his presence (cultural transmission). The apes spontaneously created new
utterances and used metaphors and combinations of signs, e.g. water-bird was
Washoes way of referring to a duck (productivity). There was no similarity between
the manual signs or plastic tokens and the real objects or concepts (arbitrariness).
The apes were able to talk about the past, things not immediately present, and places
they could not see (displacement). Some apes used warnings like angry and bite without attacking (specialization), and they definately related sign and meaning
(duality of pattern). Also the use of language to mislead others purposely
(prevarication), was found. Falsity of meaning requires a creative and dishonest system as an instinctively induced limited set of calls is honest. Apes are very
good at social manipulation. They can interpret the behaviour and intentions of their
fellows, and they can deliberately control some facial expressions and body
language in order to mislead others. The ability to lie, to hide your feelings and
intentions, is a very important human-like behaviour and very much like direct
communication.
Unless we teach apes some language that humans also know, the only other
possibility is them teaching us their language. No doubt studies of apes in the wild
would be very profitable. Among themselves primates use a wide variety of
communication (e.g. olfactory, auditory, tactile, visual, and vocal). The meaning of
primate communication depends on the social and environmental context as well as
the emotional state of the animals, and their calls appear to be like complete human
utterances, e.g. you may mate with me (Bickerton 1990:10-12).
The monkeys called vervets have the most sophisticated animal communication that
we know of (Diamond 1991:126-128). Frequently, like other wild animals, vervets
are in dangerous situations in which an efficient communication system increases
their possibility of survival. Also, they have complex social relationships, territorial
rivalry and fights, and they have to be able to inform each other about sources of
food.
The application of new techniques, e.g. modern tape-recordings and the
spectographic analysis, has made it possible to detect variations which humans
cannot perceive. For instance the vervets produce several distinct alarm calls naming
the different kinds of predators, they react differently to dominant and subordinate
members of their own troop, to their families, and to members of rival troops.
Like humans, vervets have to learn part of their language. The young vervets appear
to generalize and cannot produce the distinct calls until they reach a certain age.
Also, they have to learn how to react to the various calls. The observations of
behaviour by T. Struhsaker and the sound experiments by R. Seyfarth and D.
Cheeney (Diamond 1991:128-132) have shown a connection between behaviour and
call as a deliberate communication which cannot be explained as
stimulus-determined expressions as they are messages given honestly to friends or
dishonestly to enemies. Also, this shows how easy it is to underestimate the
communicative abilities of other species. So far, no evidence of syntax has been
discovered, but this is no proof that it does not exist. Most of the calls seem to be
single utterances or repetitions of the same call.
Gibbons, too, have calls that differ from each other, similar to those of the vervets.
Sometimes they consist of more elements in certain combinations, but the meaning
of these have not yet been decoded by humans. Certainly, many other species may
have calls, the meaning of which we have not yet recognized.
Formerly, it was assumed that the only world was the one bounded by the limits of
our senses, but there are sensory worlds outside our own beyond our ability to
perceive. The application of new techniques such as the use of spectrograms in order
to study animals in the wild may one day reveal other complex systems for
receiving, analysing, and exchanging signals, perhaps even using a kind of syntax.
Contrasting tones and pitch contour may be important features. A single vowel can
have eight different meanings in the Iyau language of New Guinea (Diamond
1991:133-134), and a small variation of pitch can change the meaning of the word
mother-in-law into that of snake. A warning call could be modified when given
different intonations with distinct meanings, e.g. Watch out! A snake!, Is there a
snake?, This is not a snake., etc. (Bickerton 1990:11-13).
Travel books from the nineteenth century are full of tales of primitive native tribes
who used very few words (Diamond 1991:137), and the European travellers found it
just as difficult to understand the unfamiliar sounds of these languages as zoologists
find it when trying to decode the sounds of birds, whales, or primates.
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