The millennial and close relationship between dogs and humans has been the subject of many scientific studies, which reveal that from the muscles around the eyes to the release of oxytocin hormone facilitate the relationship of dogs with us.
Since many of these studies have involved domesticated, home-bred and minimally trained animals, the question remains: do stray dogs react in the same way?
Biologist Anindita Bhadra of the Institute of Education and Scientific Research in Kolkata, India, has been researching specific dog populations for years – and seeks to answer that question.
According to the author, stray dogs are the largest group of dogs in the world and their bond with humans is marked by various factors, including social and economic.
The latest work by Bhadra and his collaborators was published in the journal Frontiers in Psychology and tested the reaction of homeless animals to commands from unknown humans. The test had already been done in other studies, but always with pet owners.
When faced with two containers of food, stray dogs in most cases chose the one to which the human pointed.
The team conducted an Ig Nobel-worthy experiment on the streets of cities in the Indian region of West Bengal, the prize that praises funny and often strange scientific research. The first phase was familiarization: a person would show a stray dog a piece of raw chicken that the animal could smell, and then this meat was put into a container.
Then the food was put into a jar, leaving a second container empty. An instructor then stepped in. Not knowing where the chicken was, he pointed to one of the containers on the floor. Detail: Everything is millimeter-measured, with predefined distances between the pots, the instructor and the dog. The team also produced reports and footage of the experiments.
120 animals were tested. Of these, nearly half (59) approached one of the pots – the others stood still or headed in the other direction, which scientists associate with a state of anxiety and possibly the result of previous negative experiences. Of those who approached, about 80% (47 dogs) went in the direction the instructor pointed, regardless of what was there.
There were also tests with a control group of 40 animals to see if other variables could influence the choice of pots, which was not confirmed – the human influence was evident. That’s why Bhadra’s team says dogs are born capable of understanding certain human actions, even without training.
“We found it very encouraging that dogs could follow such an abstract gesture as pointing with their hands,” Bhadra said in a press release. “This means that they watch humans closely, including those they see for the first time, and use this understanding of humans to make a decision. This shows the intelligence and adaptability of these animals.”
A combination of genetic factors and life experiences explains dogs’ behavior toward humans, researchers say – Photo: Getty Images / BBC
In analyzing the group of dogs that deviated from the tests, the researchers point out that “lifelong experiences can be different and have a significant impact on dog behavior.”
“Stray dogs are found in most developing countries and live without direct human supervision. They interact with humans regularly and receive positive stimuli, such as food and affection; and negative stimuli, such as aggression…” in the Frontiers in Psychology.
Bhadra says the research results, by broadening our understanding of our relationship with animals, may improve it.
“We need to understand that dogs are intelligent animals that can coexist with us,” he says. “They are very capable of understanding our body language, and we need to give them space. A little empathy and respect for other species can greatly reduce the conflict.”
‘Man’s best friend’ for thousands of years
The article has a contextual chapter, in which the authors point out that other animals react to human gestures, such as chimpanzees, horses, elephants, goats and cats.
Dogs are possibly one of the first species of domesticated animals, 10,000 to 30,000 years ago, according to different interpretations. Descendants of wolves have adapted to living with humans – which according to the literature did not bring us benefits initially, although later they began to be used in activities such as hunting and herd control.
Like the study now published, others had already demonstrated the ability of dogs to react to different types of human gestures.
Thus, both genetic factors and individual life-long experiences may explain the behavior of dogs.
It has also been shown that dogs produce oxytocin, a hormone related to social connection in mammals, in the presence of humans.
Researchers at the University of Portsmouth, England, have published a study also showing muscle adaptations around dog eyes that allow for particularly attractive facial expressions for humans – such as a childlike look and similar to human eye movements when sad.
“When dogs make this move, they seem to arouse in humans a strong sense of protection,” Juliane Kaminski of the Portsmouth team explained in 2019.