Horses and pigs understand harsh spoken vocalizations

The idea of ​​horse whispers—who have a talent for communicating with horses—may bring a laugh to many. But there may be something about his whispering skills, according to new research from the University of Copenhagen and ETH Zurich. In an international collaboration, behavioral biologist Elodie Briefer of the University of Copenhagen’s Department of Biology, along with researchers Anne-Laure Magroot and Edna Hillman, investigated whether a range of animals could differentiate between positively and negatively charged sounds. Is.

“The results showed that domesticated boars and horses, as well as Asian wild horses, can tell the difference, both when voices come from their own species and close relatives, as well as human voices,” explains Elodie Briefer. Pigs were studied along with pigs, their wild relatives. As in the case of the two related horse species, the pigs reacted explicitly to how emotionally charged the sounds of their counterparts were. In fact, to the same extent when it comes to their own kind of voices.

The animals also showed the ability to differentiate between positively or negatively charged human voices. While their responses were more suppressed, wild boars reacted differently when exposed to human speech, which was superimposed by either positive or negative emotion.

human gibberish

The researchers recorded animal sounds and human voices from hidden speakers.

In order to avoid the pet reacting to specific words, positive and negative human speech was performed by a professional voice actor in a kind of ambiguity without any meaningful phrases.

Animals’ behavioral responses were recorded in several categories used in previous studies – everything from the position of their ears to their movement or lack thereof.

Based on this, the researchers concluded that: how we talk to animals.

“Our results suggest that these animals are influenced by the emotions we charge our voices with when we talk to or are around them. They react more strongly – usually faster – when They are met with a negatively charged voice, then a positively charged voice is played to them earlier than having one. In some situations, they also reflect the emotion to which they are exposed” Elodie Briefer it is said.

Do animals have emotional lives?

Part of the aim of the study was to investigate the possibility of “emotional contagion” in animals—a type of reflection of emotion. Situations where one expressed emotion is assumed by another. In behavioral biology, this type of response is seen as the first step in the sympathetic category.

“Should future research projects clearly demonstrate that these animals do reflect emotions, as this study shows, it will be very important in relation to the evolutionary history of emotions and the emotional lives and levels of consciousness of animals.” Will be interesting.” Elodie Briefer.

The study was unable to detect explicit observations of “emotional contagion,” but an interesting result was the order in which the sounds were delivered. The scenes in which the negative sound was played first elicited strong responses in all except the wild boar. This included human speech.

According to Elodie Briefer, this suggests that the way we talk around animals and the way we talk to animals can have an impact on their well-being.

“This means that our voices have a direct effect on the emotional state of animals, which is very interesting from an animal welfare point of view,” she says.

This knowledge not only raises ethical questions about how we view animals – and conversely, it can also be used as a tangible means of improving the daily lives of animals, if those who work with them Get acquainted with it.

“While animals first reacted strongly to hearing negatively charged speech, the same is true in the opposite. That is, if animals were initially spoken in a more positive, friendly voice, then people When met, they should react less. They may be calmer and more relaxed,” explains Elodie Briefer.

The next step for the University of Copenhagen researcher is the switchover. He and his colleagues are now looking at how well we humans are able to understand animal emotions.

How did the researchers do it

• The animals in the experiment were either privately owned (horses), living from a research station (pigs) or in zoos in Switzerland and France (wild Przewalski’s horse and wild boar).
• The researchers used the sounds of animals with previously established emotion valence.
• Animal voices and human voices animals were played from hidden speakers.
• To do this requires high sound quality to ensure the natural frequencies are best heard by animals.
• The sounds were played in sequence with first a positively or negatively charged sound, then a pause, – and then sounds with reverse valence, that is, reverse emotion.
• The responses were recorded on video, which the researchers could later use to observe and record the animal’s reactions.

Three researches may explain animal responses

The researchers worked with three principles to determine what conditions they expected to affect the animals’ responses in the experiment:

phylogeny

• According to this theory, based on the evolution of the species, that is, the evolutionary history, animals with a common ancestry may be able to hear and understand each other’s sounds based on their common biology.

domestication

• Prolonged close contact with humans may have increased the ability to interpret human emotions.
• Animals that are good at capturing human emotions may be preferred for breeding.

Introduction

• based on learning. Specific animals in the study would have learned a greater understanding of humans and companion species with whom they were in close contact with where they were kept.

The conclusion is as follows. Among the horse species, the phylogeny thesis best explains their behavior. In contrast, the behavior of the pig species is best suited to the domestication hypothesis.

The study was initiated at ETH Zurich and funded by the Swiss National Science Foundation