An international team of researchers has found that dogs react noticeably more strongly to human crying than to humming a melody, though the degree of their attention depends directly on the animal's living conditions. The authors of the study, published in the journal Scientific Reports, report this, according to infohub.kz.
The experiment involved 112 adult dogs. Of these, 45 were pets from São Paulo (Brazil), 33 were shelter dogs from Ouro Fino (Brazil), and another 34 were stray animals from West Bengal (India).
Each animal was randomly played four 20-second situations: a familiar person or an experimenter either imitated crying or hummed a melody. The results showed that all groups of dogs looked at the person more often and for longer during crying than during humming.
At the same time, the level of attention varied. Stray dogs looked at the person displaying emotions less often and for shorter periods than shelter dogs and pets, whose indicators turned out to be similar.
When the tests were repeated, the likelihood of physical contact and of looking toward the person decreased because of habituation. In addition, the dogs interacted with unfamiliar experimenters 46.5% more often than with familiar people.
Pets also turned to a neutral observer more often when they heard crying, while stray animals displayed more behavior unrelated to people.
The study's authors emphasize that the increased attention to crying indicates dogs' sensitivity to social signals, but it has not yet been proven whether this is linked to an expression of empathy.