Dogs that walk daily with their owners are less aggressive. Dogs owned by women reportedly bark less at strangers.
Heavier canines, on the other hand, tend to be less insolent towards their owners than lighter weights. Pugs, bulldogs, shih-tzus and other animals with a shortened muzzle can be more offensive to humans than dogs with a medium and long muzzle, such as the golden retriever and the popular caramel mutt.
That's what a study done by researchers from USP (University of São Paulo) with 665 pet dogs of different breeds, including mutts (no defined breed) showed.
In the research, published in the journal Applied Animal Behavior Science, morphological, environmental and social factors were related to the aggressiveness profiles of pet dogs.
Data crossing showed that not only conditions such as weight, height and snout size are associated with a higher or lower incidence of aggressiveness, but also issues related to the animals' life histories and the owner's characteristics.
According to the article, the results confirm the hypothesis that the behavior of dogs is not something defined only by learning, nor only by genetics. It is the effect of a constant interaction with everything that surrounds the animal's life. The study was supported by FAPESP through a project on the ethological approach to social communication between different species, including humans (read more here).
“The results highlight something we've been studying for some time now: behavior emerges from the animal's interaction with its context, that is, the environment and interaction with the tutor, for example, in addition to the dog's morphology, of course. All these factors have an impact on how the dog interacts with the environment and also on the way we interact with it”, explains Briseida de Resende, professor at IP-USP (Institute of Psychology) and co-author of the article.
In the study, carried out during the Covid-19 pandemic, 665 dog owners answered three online questionnaires, which provided information about the animal's characteristics, its environment, owner and aggressive behaviors, such as barking at strangers and even attacking. By crossing this information with the degree of aggression of the dogs, the researchers identified some interesting patterns.
The questionnaires were developed by IP-USP researcher Natália Albuquerque and Professor Carine Savalli, from Unifesp (Federal University of São Paulo).
“Only the owner's gender proved to be a factor capable of predicting behavior with strangers: the absence of aggression was a 73% more frequent characteristic among women's dogs”, says Flávio Ayrosa, first author of the article.
The sex of the animal also seems to influence the degree of aggressiveness. “The chance of the animal being hostile towards the owner was 40% lower in females than in males”, says the author.
“But it was in the comparison between snout size that we found a more significant difference: the chances of aggression against the owner tend to be 79% higher in brachycephalic dogs [focinho achatado] than in mesocephalic patients”, he says.
On the other hand, the heavier the dog, the less the possibility of aggression against its owner. When crossing the data, the researchers identified that the chances of aggressiveness decreased by 3% for each extra kilo of body mass.
But Ayrosa points out that the findings associated with the tutor's profile are not a cause and effect relationship. “We found a relationship, but it is not possible to say which comes first. The ‘dog walking' factor, for example: it could be that people walked their dogs less because they are aggressive animals, or the dogs could have become more aggressive because their tutors didn't walk with them”, he says.
“Characteristics such as weight, height, skull morphology, sex and age influence the interaction between dogs and their environment. This can make the animal spend more time at home, for example”, he adds.
Historically, the aggressiveness of dogs has been associated solely and exclusively with the issue of breed. This paradigm began to change in the last ten years, when the first studies appeared that related behavioral profiles with factors such as dog age, gender, metabolic issues and hormonal differences. In Brazil, the research coordinated by the IP-USP group was the first to assess morphological and behavioral issues, including aggressiveness, in mixed breed animals.
“Only more recently have studies begun to investigate the influence of factors related to morphology, animals' life histories, tutor characteristics, origin [comprado ou adotado]as is the case in our study”, says Ayrosa.
O artigo Relationships among morphological, environmental, social factors and aggressive profiles in Brazilian pet dogs pode ser lido aqui.
– 12/14/2022 – Daily life