IN an international collaboration, along with researchers Anne-Laure Maigrot and Edna Hillmann, behavioral biologist Elodie Briefer of the University of Copenhagen’s Department of Biology investigated whether a range of animals can distinguish between positively and negatively charged sounds.

“The results showed that domesticated horses (and pigs), as well as Asian wild horses, can tell the difference, both when the sounds come from their own species and near relatives, as well as from human voices,” explains Elodie Briefer.

The researchers played recordings of animal sounds and human voices from hidden speakers. To avoid having the domesticated animals react to specific words, positive and negative human speech was performed by a professional voice actor in a kind of gibberish without any meaningful phrases.

The animals’ behavioral reactions were recorded, everything from their ear position to their movement or lack thereof. On this basis, the researchers concluded that how we speak does matter to animals.

Researcher Elodie Briefer said: “Our results show that these animals are affected by the emotions we charge our voices with when we speak to or are around them. They react more strongly -- generally faster -- when they are met with a negatively charged voice, compared to having a positively charged voice played to them first. In certain situations, they even seem to mirror the emotion to which they are exposed.”