Péter Pongrácz, a biologist at Eötvös Loránd University inBudapest, recently demonstrated that humans have an innate ability tounderstand dog barks. Pongrácz played several artificial bark sequencesthat conveyed five emotional states—aggressiveness, fear, despair,playfulness, and happiness—to 90 human volunteers. The human listeners,regardless of their experiences with dogs, were able to translate eachemotional state correctly by keying in on three basic acousticqualities: tone, pitch, and timing. High-pitched barks separated bylong time intervals were interpreted as happy and playful,deep-sounding, rapid-fire barks as aggressive.
While the repertoire is impressive, Pongrácz points out that it maynot be all that surprising, given the closely entwined histories of thetwo species. “It’s interesting that dogs seem to have evolved thisenriched barking behavior, because their most important communicationis with humans.” It could be that dogs have been selected for bettercommunication—for example, dogs that stood at the edge of a village andalerted human inhabitants of danger would most likely have been favoredby humans, he says.