dogs can feel their pain, this could be innate. A community science study that compares the reactions of dogs and domestic pigs to the sound of people who compared crying and sums suggests that this is the result of centuries of co-evolution with humans. The results were published on July 2 in animal Behaviour 1 .

People pay attention to how the animals feel in their lives and it seems that this attention is mutually. Researchers found that horses stop and listen to human growls longer than on laughter 2 . Pigs react more to human sounds than wild boars 3 .

However, there are no studies that test whether the animals only react to strange human noises or are able to experience true emotional contagion - the ability to interpret and reflect the emotional states of people. Most animals can only reflect the feelings from other members of their species. However, studies have shown that dogs ( Canis Familiaris ) can reflect the emotions of the people they surround 4 , 5 .

A question is whether this emotional contagion is rooted in 'universal vocal signals of emotions' that can be understood by all domesticated animals or whether it is specific to accompanying animals and dogs. In order to test this, researchers compared the stress reaction of dogs and domestic pigs ( sus scrofa domesticus ) on human noises.

animal noises

Like dogs, domestic pigs are social animals that are raised from an early age near humans. But unlike dogs, pigs were kept as farm animals during the most time of their history. Therefore, house pigs should react similarly to dogs if emotional contagion can only be learned by closeness to humans.

The team recruited dog or pig owners around the world to film with their pets in a room while they played recorded noise of crying or buzzing. The researchers then counted the number of stress behavior - such as whirling and yawning in dogs and fast ear movements in pigs - which were shown during the experiment.

As expected, dogs were "very, very good at grasping the emotional content of our moods," says study mitar Paula Pérez Fraga, behavioral researcher for animals at the Eötvös Loránd University in Budapest. Dogs were stressed when they heard the crying and mostly reacted unimpressed to the buzz. Pigs, on the other hand, showed some stress when they were exposed to the crying, but their behavior indicated that the sums were much more stressful.

This could be because pigs do not interpret cry as a negative emotion, says Natalia Albuquerque, cognitive etholog at the University of São Paulo, Brazil. The buzz, on the other hand, could be “very strange” for pigs who do not know how to process it.

The results suggest that accompanying animals could have a stronger emotional contagion with humans compared to farm animals. But she warns that more research is necessary. "Pigs are very sensitive," says Albuquerque. "I expected pigs to show emotional contagation."

fraga agrees. "We don't say that pigs cannot do this," she says. "The story is really about how well dogs were, not how bad pigs were."