Image: Faraj Meir/Wikimedia
Chinese white dolphins, like other cetacean species, use songs and whistles to communicate while resting, socializing, and feeding. But after analyzing the whistles from the central group, Pine and his colleagues found that they were significantly longer and much more complex than calls the researchers were more familiar with. The recorded sounds included a greater number of inflection points, where the pitch of the whistles changed abruptly. This heightened complexity signifies that the dolphins were communicating a greater amount of emotional information, the researchers conclude in a recent paper.