Can you recognize the emotion in a dog’s bark, or a tree shrew’s click? It may be more difficult than you think. The sounds of a happy animal may be harder to identify than the call of one in distress, says a new report published by a group of German scientists in the research journal PLOS ONE.
In the study, the researchers gave headphones to 28 men, sat each in a dim room, and played back sounds made by four different species: human infants, dogs, chimpanzees, and tree shrews.
RELATED: Watch This Cat Who Loves Wearing A Cardboard Box
The scientists then asked participants to identify the animals by species and emotional state. Perhaps unsurprisingly, none of the subjects could recognize the tree shrew. On the other hand, the participants positively identified human infants and dogs more than 90% of the time. (And, yes, the human infant sounds were, by and large, correctly identified.) But, while the men recognized that barks and growls signified an unhappy dog, they couldn’t discern the positive barks of dogs at play. And, while roughly three-fourths of the study participants recognized the chimpanzees’ loud cries as the sounds of a primate, few could identify the chimps’ low, laughing sounds. Once the experiment was finished, many of the participants “were surprised to learn that chimpanzees could produce such laughter sounds at all,” the authors write. The cries of chimpanzees “are very loud” and “may be encountered in zoo settings or in the media,” the authors note, but the soft sounds of chimp laughter are “rarely displayed.”
RELATED: Rescue Groups Flies Chihuahuas To Their New Homes
The stronger reaction to negative sounds may be due to our evolutionary wiring, the authors suggest, as a way to recognize threats. But, as they point out, understanding any animal’s call without observing it, as well, makes it much harder. It’s much easier to tell if dogs are barking happily, for example, when they’re chasing after frisbees.
NEXT: This Dog Owner Made His Pup A Bucket List
Sure, we could spend hours (er, days) browsing cat videos, but, for those who enjoy a deeper dive into the scientific and philosophical realm of the animal kingdom, there's The Dodo. Covering everything from why cats purr to sting operations on tiger poacher rings in Sumatra, The Dodo is committed to creating an unprecedented community for animal-lovers.