Baboon vocalizations

Thanks to a kind communication from Dorothy Cheney, one of the authors of the magisterial and utterly fascinating Baboon Metaphysics, I've been listening to a variety of calls made by male and female baboons.

Males use forceful and deep vocalizations, called "wahoos," to assert dominance: rather than attack each other, two males in conflict launch into wahoo contests. The animal who can produce sustained, resonant calls while leaping about is fitter, and this display settles differences without the need for high-risk fights.

Here is a wahoo or two, both from Cheney's research section of the University of Pennsylvania website.

(The second compares a high-ranking male's call with that of a low-ranking male.)

Cheney and Robert Seyfarth's long-term study is a remarkable example of profoundly humane science. No animals are intentionally harmed: the scholars and their assistants observe baboons in the wild, relying on stool samples, for instance, to analyze stress levels in individuals.