The woman behind the study, published in the most recent issue of Science, is Claire Spottiswoode, a researcher at the University of Cambridge, who first learned about the honeyguide as a child in South Africa. And whereas scientist H. A. Isack had published a study about human interaction with honeyguides in 1989, also in Science, Spottiswoode wanted to know if there were specific human sounds that attracted or repelled the birds.
Turns out, the birds listened for a specific call—no random shout or noise would do the trick. When hearing this call, the birds would be more response, and humans would be three times more likely to have a successful honey hunt. What's perhaps most intriguing, though, is that there is no one specific call, as people all over the continent communicate with the bird differently.