STAND ASIDE DR DOLITTLE! ANY HUMAN CAN READ ANIMALS’ MINDS, ACCORDING TO A RECENT STUDY.
Forget talking to the animals; most people can routinely read their minds. New research shows that humans can gauge animals’ emotional states based solely on the sounds they are making.
Biologists led by Piera Filippi of the University of Aix-Marseille, France, have found that humans can tell from an animal’s call whether it is aroused or relaxed – and not only primates and other mammals, but birds, reptiles and amphibians, too. Species they investigated included Barbary macaques, African elephants, American alligators, ravens and hourglass treefrogs.
This holds true for English, German and Mandarin speakers. “So this is not driven by culture. It seems to be biologically rooted,” Filippi tells BBC Wildlife.
So how are we able to spot aroused vocalisations? “It’s about the tone of voice,” she says. The pitch is important – the higher the arousal, the shriller the sound.
“The fact this works for all eight species tested, including groups that are so ancient and distant from us, suggests this characteristic was already present in the earliest terrestrial vertebrates,” says Filippi. That might be because we’re all equipped with variations on the same basic vocal apparatus, which vibrates when air is forced through it. “During arousal, muscles are tenser and pressures are higher,” she adds.
Filippi is now planning to test whether insects, too, conform to the pattern. That would be remarkable, given that insects don’t even vocalise, but produce sound by rubbing parts of their bodies together.
Meanwhile, humans might not be alone in our ability to discriminate other species’ emotional states from their calls. Filippi’s team is currently testing whether black-capped chickadees can also do it, by training them to recognise the aroused vocalisations of one species then seeing if they can generalise to others. “Such a skill might be useful for detecting imminent dangers,” she says.
Humans can tell if an animal is stressed by the sounds it makes.