March 10, 2008

Pyow, hack, everybody! Monkeys again

For those who read the Daily Telegraph, let me just point out that the new story about the putty-nosed monkeys saying "Pyow hack" seems to be... well, basically just the old story about the putty-nosed monkeys saying "Pyow hack", the one that Language Log has discussed at least three times before. The funniest post (also the first) was certainly David Beaver's And people say we monkey around, on May 18, 2006. I commented, with a sarcasm that I hope actually raised welts on exposed skin, in a post called "Homo journalisticus" on May 19th, after I saw the headline "Monkeys use 'sentences', study suggests". Some days later Mark Liberman later discussed some of the better reporting on the story in his Monkey words on May 28. I cannot see anything new in the Telegraph's story today. Except for the part that doesn't seem to make sense.

The Telegraph story (headlined "Monkeys communicate in sentences" — sic) is based on a paper in Current Biology that I have not yet seen. It says of work by Kate Arnold and Klaus Zuberbühler on the alarm calls of putty-nosed monkeys:

Now in the journal Current Biology the researchers say that these calls function in similar ways as morphemes - the smallest meaningful units in the grammar of a language so for instance, a word such as 'cat' or a prefix such as 'un-'.

This seems to be the same old absurd overstatement as before. Making two distinguishable calls in quick succession is not the same as controlling a word-formation device like the prefix un-. People are so inclined to just look for gross conveyed meaning that they overlook all of the details that make human language interesting to study. The prefix un- attaches to many adjectives to create new adjectives denoting the complement of a property (unhelpful denotes the property possessed by all and only those entities that are not helpful). Some adjectives — color adjectives, for example do not take it. The same prefix (or a prefix of the same form) attaches to some verbs to form new verbs denoting inverses of reversible processes (to untangle something is to reverse the process of tangling it). Many verbs do not take it: *unsneeze is not a verb in English. Nothing remotely like any of this is found in animal communication.

Moreover, the headline said "sentences". Morphemes like un- don't combine to form sentences. They are involved in morphology (word structure). Failing to draw this sort of distinction is like writing on personal finance and investment when you don't know stocks from bonds.

But the unintelligible bit comes when the writer, Roger Highfield, makes some remarks about how the supposedly new results "challenge the notion, commonly held by theorists, of why grammar evolved from simple vocal languages which use a different sound for every different meaning." I'm not quite sure who has ever voiced the view that once every meaning was conveyed by a different sound; but the mysterious bit is what comes next:

Prof Martin Nowak of Harvard University, a pioneer in a field called evolutionary game theory, showed that there is a limit to the range of sounds that can be made and easily distinguished. So for complicated messages it is more efficient to combine basic sounds in different ways to convey different meanings.

"Our research shows that these assumptions may not be correct," Dr Zuberbühler says. "Putty-nosed monkeys have very small vocal repertoires, but nevertheless we observe meaningful combinatorial signalling."

He points out that, unlike humans, most primates are limited in the number of signals they can physically produce because of their lack of tongue control. Thus grammar did not come about because there were too many different sounds to make in different scenarios, but not enough: combining these few calls in different ways meant that they could use them to describe more situations.

I may be missing something, but Nowak and Zuberbühler seem to me to be both saying the same thing: that when you have only a very limited inventory of sounds, you need to string them together to make a larger inventory of conveyed messages. Zuberbühler is not contradicting Nowak's assumptions. He is agreeing. Perhaps some paragraphs got reordered in the writing, or perhaps Nowak is cited as further support for the new view rather than an illustration of the supposed old view. I don't know. But I can't make head or tail of it: I just can't see what Highfield thinks is the relation between Nowak's game theory and the new (old) pyow-hack story. This is not good science writing.

But then it's never time for good science writing when it's animal communication time. It is, like quite a number of other subjects, a topic that turns science journalists' brains to mush.

Posted by Geoffrey K. Pullum at March 10, 2008 03:56 PM