Those crafty scientists at the University of St Andrews have managed to decipher monkey language, it seems:
“Krak” is a call that warns of leopards in the vicinity. The monkeys gave it in response to real leopards and to model leopards or leopard growls broadcast by the researchers. The monkeys can vary the call by adding the suffix “-oo”: “krak-oo” seems to be a general word for predator, but one given in a special context — when monkeys hear but do not see a predator, or when they hear the alarm calls of another species known as the Diana monkey.
The “boom-boom” call invites other monkeys to come toward the male making the sound. Two booms can be combined with a series of “krak-oos,” with a meaning entirely different to that of either of its components. “Boom boom krak-oo krak-oo krak-oo” is the monkey’s version of “Timber!” — it warns of falling trees.
This seems to be based on this PLoS One paper from November. They basically correlated vocalizations with features of the environment (ok, they used a GLM). They then used these features, such as the presence of a jaguar, as templates and simulated their arrival in the environment to check their predictions. They were right. The important point isn’t that the monkeys have words, but rather that they string together words to modify meaning (ie, they use syntax). Here’s how they sum it up:
[I]t is still largely unclear whether non-human primates intentionally inform their audience about the event they have just experienced, or whether their vocal response is more directly driven by the psychological processes triggered by external events, the currently prevailing hypothesis. What our results show is that callers appear to make some judgements about the nature of the event (tree fall, group gathering to travel, conspecific intruder, eagle, leopard), and that this assessment determines whether or not affixation takes place. Equally important, male Campbell’s monkeys rarely produce single calls but almost always give sequences of different call types.
I just want to know when we can hold a conversation with them that contains more content than an interview Sarah Palin. Zing!