Human yawning is contagious to dogs, especially if the human yawning is the dog's owner, a Portuguese researcher has found.
Joana Bessa from the Abel Salazar Institute of Biomedical Sciences of Oporto University began her research by looking at studies that had already been carried out on whether yawning was contagious. These initial studies had diverging results, so she tried to find proof of whether animals could 'catch' human yawns.
With cooperation from Karine Silva and Liliana de Sousa, the scientist achieved "positive results" and concluded that "there was contagion by the dogs but there was also social modelling."
"We tried to replicate the studies to understand if we could find proof that the dogs could catch human yawning, but we also tried to understand whether there was any influence of empathy," Joana Bessa told Lusa News Agency earlier this month.
"The dogs yawned more when they heard humans they knew yawning, like their owners, as opposed to people they didn't know, and the possibility that dogs could have some empathy with humans came about," she said.
A total of 29 dogs took part in the study and were exposed to the sounds of human yawns. The option to avoid visual contact was aimed at removing the possibility that the yawning could have been the imitation of what they saw humans doing.
The dogs heard the sounds of different people yawning, including their owners and people they didn't know, as well as an artificial control sound in different sessions each carried out seven days apart.
According to the researcher, future studies could determine a dog's personality or the existence of empathy with humans, which could make it possible to choose animals that are more adapted to certain situations, such as guide dogs.
Dogs and horses are in some cases used for the therapy of disabled children and adults.
Joana Bessa added that if it were proven that empathy is related with the contagion of yawning, that information "could be applied to various species."
The researchers work is to be published in the Animal Cognition magazine after being presented at the 9th National Ethology Congress in Lisbon this month.