The Telegraph (Dec 2007) has a story on Liz Hawkins’ research into dolphin communication which claims they might be using language.
Basically, they used different whistles and clicks depending on environmental and behavioral context. Not exactly a surprise: many species do this. Vervets monkeys are well-known for making distinct alarm calls to their fellows based on the type of predator spotted. But is this enough to call it language?
Linguists have identified a handful of general properties of human language which give it its expressive power. Some of the crucial ones:
- Arbitrariness: the sounds, letters or hand-signals used do not directly resemble the objects or ideas they refer to. The word cheetah does not look or sound like a big cat, and a vervet’s alarm call when eagles and hawks are around does not sound like a bird.
- Productivity: can create new strings (combinations of sounds or words) from smaller pieces, i.e. can say something that has never been said before, and people will understand.
- Displacement: allows reference to the past or future, or things out of immediate sight/experience. We can talk about yesterday’s weather and events that never happened.
- Duality: has two levels — meaningless sound pieces (phonemes) and semantic meaning (morphemes, words, etc.) — operating at the same time. That is, mouth sounds like the ‘b’-, ‘a’- and ‘t’-sounds in “bat” mean nothing alone, but in the proper sequence they refer to an animal.
Whether all of these (and other important properties) are necessary to classify communication as strictly linguistic, it is clear that what we normally mean by language (i.e. human-like communication) is much more complex than simply producing different sounds or signals in distict contexts. So they’ve got a long way to go in establishing that dolphin communication is a “language” in anything close to the same sense by which we apply that term to human communication.
Certainly, other researchers have done work investigating dolphins’ communicatory abilities (including linguistic precursors like equivalence classes), but as of yet, most scientists in the field would probably not be comfortable calling it language. That’s one problem with popular media science writing: the writer tends to go for catchy, succinct headlines and descriptions that at best over-simplify scientific results, and at worst present outright falsities. It is important to spread scientific knowledge, but we must also spread scientific literacy in order for that knowledge not to be corrupted.
At any rate, the Telegraph article ends with a quote from Liz Hawkins: “Dolphin communication is much more complicated than we thought.” Fair enough, but perhaps she should replace the word ‘complicated’ with ‘flexible’. Making different whistles when feeding versus traveling is not exactly complicated.
There’s still a lot of research to be done, but this is a really exciting area because dolphins provide a rich source of data from an evolutionary line rather distinct from primates (the target of most animal language research in the last half of the twentieth century). Nice to see that field work is complementing the controlled experimental work.