American researchers examined how the appearance of dogs affects their expressiveness from a human perspective. The study involved volunteers along with their dogs. In total, there were 103 pets, with an average age of 5.2 years.
In the course of the study, pet owners participated in a survey, took pictures of their pets' faces, and recorded four thirty-second videos with them.
The dogs' faces were studied considering their shape, symmetry, color, and markings. The animals were also evaluated by strangers.
As the experiment demonstrated, the markings and color of pets' faces have the same impact on the perception of their facial expressions as markings on the faces of primates: those that are simpler are perceived as more expressive.
Moreover, mature dogs—aged 2 to 7 years—appeared more expressive than older ones. This also depended on the training of the animal.
According to the researchers, it is necessary to take into account the results of the study, as the relationships between humans and dogs continue to evolve both from an evolutionary perspective and in the context of training and the well-being of our smaller brothers.
