A new study conducted in Spain has revealed that wolves, the closest wild relatives of domestic dogs, possess the ability to discriminate between familiar and unfamiliar human voices. The findings suggest that dogs’ capacity to recognise their owners’ voices is not solely a result of domestication but may be rooted in their common ancestor with wolves. The study provides valuable insights into the cognitive abilities of vertebrate species and sheds light on the social behaviour of animals. The findings were published on Animal Cognition.
The research, carried out between June and July 2018, involved 24 captive wolves from five animal establishments in Spain. These wolves, aged between 1 and 13 years, were born in captivity and had regular interactions with humans, particularly their keepers. The wolves’ keepers provided daily rewarding interactions such as feeding and handling, and they formed a significant part of the wolves’ socialisation process.
To test the wolves’ ability to distinguish between familiar and unfamiliar human voices, the researchers employed the habituation-dishabituation paradigm. The wolves were presented with playback recordings of their keepers’ voices as well as voices of strangers, producing either familiar or unfamiliar phrases. The researchers observed that the wolves exhibited a significantly longer response duration when presented with their keepers’ voices compared to strangers’ voices, indicating that the wolves could discriminate between familiar and unfamiliar speakers.
The study’s findings suggest that the ability to recognise human voices may be a shared trait between dogs and wolves, originating from their common ancestor. This challenges the notion that dogs’ voice recognition skills are purely a result of their domestication process. The results also support the idea that vertebrates, including both conspecifics (members of the same species) and heterospecifics (members of different species), possess a general ability to recognise and discriminate between individuals based on identity cues.
Furthermore, the study provides evidence of familiar voice discrimination in a wild animal kept in captivity, indicating that this ability may be prevalent among vertebrate species. Previous studies on conspecific vocal discrimination in wolves, as well as studies involving other animals such as domestic cats and captive cheetahs, have similarly demonstrated their ability to differentiate between familiar and unfamiliar voices.
The research team also highlighted the possibility that wolves may rely on specific acoustic cues to discriminate between voices, similar to dogs. Previous studies on dogs have shown that features such as fundamental frequency and periodicity of vocal fold vibration play a role in owners’ recognition. Similarly, wolves have been found to utilise howl features, such as fundamental frequency and frequency modulation, to recognise familiar conspecifics. Exploring the cues used by wolves to discriminate between voices could offer valuable insights into their cognitive processes.
This groundbreaking study deepens our understanding of the social behaviour and cognitive abilities of animals. It highlights the remarkable capacity of wolves, and possibly other vertebrate species, to recognise and distinguish between familiar and unfamiliar human voices. Further research in this area may unravel additional aspects of animals’ auditory perception and contribute to our understanding of the evolutionary origins of social behaviour and communication.