The Evolution of Language
Book Review of The First Word
The Search for the Origins of Language
Penguin Books, 2008
About the Author: Christine Kenneally was born in Australia and received her Ph.D. in linguistics at the University of Cambridge. She has written about language, science, and culture for publications such as The New Yorker, The New York Times, Scientific American, and Slate.
In The First Word, author Christine Kenneally traces the development of the field of evolutionary linguistics from its early speculative history through to its modern emphasis on genetics and computational modeling. Along the way she enthusiastically spins narratives of the fractious professional debates between prominent individuals in the field, outlines major steps in human evolution, describes the anatomy of the human brain, details the cognitive difficulties of oxygen-deprived mountain climbers, and explains similarities and difference between human anatomy and that of other great apes.
Kenneally is most ardent when she describes research into animal cognition, and the efforts to teach various species some form of human language. She finds the human capacity for language not so remarkable in light of a new appreciation of the abilities and behaviors shared by many kinds of animals, and less extraordinary also because humanity has an inflated view of its own linguistic and cognitive potential. She favors the view that language ability evolved as an adaptation, involving many parts of the human brain and body, and that evidence of this adaptation can be found throughout the animal kingdom.
Many researchers believe that for language to have evolved, there first had to be a need to speak, as opposed to having language evolve suddenly and then finding there was a lot to talk about. In this view, language ability was not an accident, nor was it brought about by a sudden enabling mutation for grammar. If language ability evolved in the same adaptive way as most other abilities, then the search for the origins of language includes a search to uncover what was so advantageous to communicate. It is helpful in this search to study what goes on in the minds of nonlinguistic creatures.
Animals that demonstrate relatively advanced cognitive abilities suggest what the minds of our prelinguistic ancestors may have been like. Many species that demonstrate complicated thinking have a fair amount in common with humans – dolphins, elephants, and crows all have long lives, extended infancy, complicated systems of communication, and societies where individuals have distinct roles. Female elephants, for example, live years beyond their reproductive age and pass on learning to youngsters, such as how to interact with other elephants, as well as information about water holes or fruit trees.
Elephants also appear to use sounds like words. Researchers found that individual elephants produce distinct sounds for different purposes, like greeting a fellow member of the clan they haven’t seen for a while. Similarly, dolphins use echolocation clicks and purposeful types of whistles, and appear to name themselves with a “signature whistle.” Whenever they meet another dolphin they produce a distinct, individual sound, which develops in their first year of life. And there is evidence that dolphins exchange signature whistles when separating.
Vervet monkeys make three different word-like alarm calls when they see a threat from ground, tree, or air, warning their group to take appropriate defense. Some researchers think that these alarm calls may be “protowords,” a primitive form of language. When animals make alarm calls, they are connecting a particular sound to a referent in the world. Every species of animal that researchers have studied so far can link sound and a referent. Humans have built on this ability by using this ancient platform for sound and referent to evolve human language.
Language is built in two levels of construction. At the first level, sounds from the set comprising the language – its phonemes – are combined into meaningful sounds known as morphemes. There are for example about 44 phonemes in English (depending on the dialect), which are combined to make parts of words and words themselves, such as “micro” and “wave.” Morphemes are found in birdsong, in the songs of whales, and in other animal vocalizations. The morphemes in these songs recur repeatedly, but perhaps surprisingly, no animal vocalization, not even birdsong, has the range of sounds that humans possess.
At the next level, morphemes are combined into phrases that are usually intended to convey meaning. Linguists call this syntax – the rules for combining words in a recognizably correct manner. As Chomsky noted, we produce syntax separately from meaning, as when one constructs the grammatically correct but meaningless, “Colorless green ideas sleep furiously.”
Until recently, it was believed that only humans could make use of the structural rules of syntax, but different types of syntax have been observed in the communication of a number of primate species, including chimpanzees and gibbons. Gibbons arrange sounds into structured vocalizations that are quite different from those of most other primates in order to produce complex songs, used to communicate up to one kilometer in distance. What is important about these gibbon utterances is that the same set of sounds has two different meanings to a gibbon when ordered in two different ways. The simple structural rules used by these primates in the wild contradict the idea that creating meaning with a defined structure – for example, subject, verb, object – is a special human ability.