"This kind of study highlights the continuity between humans and animals, not only from a morphological, anatomical and physiological point of view, but also from a psychological and emotional point of view," Palagi says. "The human mind, like body, has evolved in continuity with other animals."
One challenge with calling such consolation sympathetic concern is that the researchers were measuring behaviors, not emotions per se, says developmental psychologist Carolyn Zahn-Waxler of the University of Wisconsin–Madison, who did not participate in this research. Future work could also investigate chimp vocalizations or even facial expressions to help overcome this issue, she notes. "Having visited the Yerkes Center firsthand, I myself have no doubts these behaviors the researchers are detailing are parallel to the first forms of comforting behaviors we see in human children," Zahn-Waxler adds.
Future research could also investigate more distant relatives of humans. "To date, there is no evidence that consolation is present in monkeys," Palagi says, "but we are working on an interesting [monkey] species, the gelada, in which females are extremely bonded. Preliminary data suggests that true consolation could be present in this species and, if the data are confirmed, will be a further important step in understanding the consolation mechanism and the cognitive scaffold at its basis."