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Why Dogs Understand Humans, Even Without Training

Analysis by Dr. Karen Shaw Becker

 
  
  • March 13, 2020

STORY AT-A-GLANCE

  • A newly published study suggests that dogs’ ability to understand human gestures may be innate
  • The study involved 160 stray dogs in India; the researchers found that 80% of dogs willing to approach two bowls on the ground did so in response to a human pointing to the bowls
  • To survive on the street, pet dogs would need to reacquire the survival skills of free-ranging dogs that have been lost to domestication
  • Domestication has also led to genetic changes that would inhibit dogs’ ability to survive on their own

 

 

Most of us with dogs assume our canine companions learn to read our communication cues through training and also because we spend so much time together. But fascinating new research suggests there may be more to the story.1

Believe it or not, 80% of untrained stray dogs observed for a recent study "successfully followed pointing gestures to a specific location despite having never received prior training," according to a news release posted in Frontiers Science News.2

These results suggest the possibility that dogs are able to understand and respond to complex gestures without any training, meaning they may have an instinctive connection to human behaviors. According to researchers, this discovery may have implications in reducing negative encounters between stray dogs and humans.

Do Dogs Need to Be Trained to Understand Us?

Dogs are probably the oldest domesticated species on the planet and have been intentionally bred over thousands of years for traits that are both desirable and useful to humans. As a result, today's domesticated dogs are highly attuned to human physical and verbal cues.

What the authors of the current study, published in Frontiers in Psychology, wanted to learn was whether dogs understand humans through training alone, or whether some part of this ability is innate. Can a stray dog interpret certain human gestures having never been trained to do so, and having never laid eyes before on the person making the gestures?

Stray dogs running the streets isn't a common sight in the U.S., but it is in other cities around the globe, especially in developing countries. These free-ranging dogs watch and occasionally interact with people, but for the most part they behave as the wild, untrained animals they are. The result, sadly, is regular clashes with humans.

80% of Dogs Who Approached the Bowls Seemed to Understand Human Pointing Gestures

For the study, a team of researchers in India led by Dr. Anindita Bhadra of the Indian Institute of Science Education and Research in Kolkata, studied a total of 160 stray dogs living in several cities.

The researchers located solitary dogs and placed two covered bowls on the ground close to them. A researcher would point to one of the bowls, either just once or several times, and then record both the dog's response and his perceived emotional state.

About half the dogs didn't approach either bowl "even after successful familiarization with the experimental setup." According to the researchers, these dogs seemed anxious and may have had negative experiences with people in the past. In contrast, the dogs who approached the bowls appeared friendlier and less anxious.

About 80% of that group correctly interpreted the researchers' pointing signals, whether they pointed once or repeatedly, indicating the dogs were able to read complex gestures.

"We thought it was quite amazing that the dogs could follow a gesture as abstract as momentary pointing," Bhadra told ScienceDaily. "This means that they closely observe the human, whom they are meeting for the first time, and they use their understanding of humans to make a decision. This shows their intelligence and adaptability."3

Bhadra and her colleagues believe their study results indicate that dogs may have an inborn ability to understand certain human gestures. However, since anxious dogs wouldn't participate, the researchers feel more research is needed to determine how dogs' personalities (and/or perhaps past experiences) affect their ability (or perhaps willingness) to understand and respond to human cues.

"We need to understand that dogs are intelligent animals that can co-exist with us," said Bhadra "They are quite capable of understanding our body language and we need to give them their space. A little empathy and respect for another species can reduce a lot of conflict."

Free-Ranging Dogs Have Survival Skills Your Own Dog Lost Through Domestication

The domestication process has resulted in dogs being highly dependent on humans for all the necessities of life including food, water, shelter, safety, exercise, playtime, affection, health care, and more. Without us, writes veterinarian Dr. Joann Pendergrass, " … dogs would be faced with a world in which they would have to completely fend for themselves to eat, stay safe and ultimately survive."4

Since around 80% of the dogs in the world are free-ranging,5 humans could disappear from the earth and it wouldn't matter much to them.

But for the remaining 20% of pet dogs, writes Pendergrass, life without humans "… would require having some survival skills, such as forming relationships and alliances with other animals (even cats!), having an independent personality, being street-savvy, being able to rapidly adapt to changing conditions, and having a willingness to take some risks."

Skills like finding shelter from the weather and predators would involve trial-and-error as domesticated dogs honed their ability to survive in the wild.

It's possible that medium and large breed dogs would have an easier time of it than very small or giant breeds. Pendergrass also believes dogs would need to breed with other animals, in particular, coyotes and wolves, in order for them to survive longer-term in a human-free world. Interbreeding would produce future generations that could survive and thrive without humans.

Domestication Has Led to Genetic Changes That Hamper Dogs' Ability to Survive Life on the Streets

"Domestication syndrome" is a term Charles Darwin coined to describe his discovery that "domesticated mammals possess a distinctive and unusual suite of heritable traits not seen in their wild progenitors," according to a 2014 study published in the journal Genetics.6 For example, picture a wolf, and then picture a dog with floppy ears, a sweet little patch of white fur, and a baby (puppy) face.

Domestication syndrome isn't seen exclusively in mammals like dogs, rabbits, foxes, pigs, horses or sheep — it has also been observed in domesticated birds and even fish. Scientists, including Darwin, have long been puzzled by why domesticated animals have many similar features and behaviors. These include:

Depigmentation (white patches, brown regions)

Floppy ears

Smaller ears

Shorter muzzles

Smaller teeth

Docile behavior

Smaller brain or cranial capacity

More frequent estrous cycles

Juvenile behavior

Curly tails

According to the authors of the Genetics study, when certain species are domesticated with the goal of taming them, it leads to genetic changes that affect a group of embryonic stem cells called the neural crest.

Neural crest cells form near the spinal cord of early vertebrate embryos. As the embryo develops, the cells travel to other locations in the body and create different tissue types, including pigment cells, parts of the head (skull, jaws, teeth, ears), and the adrenal glands, which are responsible for the fight-or-flight response.

Neural crest cells are also indirectly involved in the development of the brain. According to the Genetics study co-author Adam Wilkins of Berlin's Humboldt University:

"When humans bred these animals for tameness, they may have inadvertently selected those with mild neural crest deficits, resulting in smaller or slow-maturing adrenal glands. So, these animals were less fearful."7

The neural crest abnormalities Wilkins speaks of could also lead to physical signs of tameness — and not all of them good. For example, floppy ears are an appealing feature on dogs and rabbits, but unfortunately, they're actually the result of deformed ear cartilage. Animals with ears flopped over and hanging alongside their faces presumably don't hear as well as those with erect ears.

Domesticated animals also appear to have smaller brains than their counterparts in the wild. The decreased size of the forebrain seen in most domestic animals could be indirectly related to neural crest changes.