Stress Management Gene in Dogs make them 'Man's Best Friend' - Japanese Study Reveals

In a widely accepted evolutionary theory, dogs are descended from wolves, and their domestication, which enabled their special relationship with humans, has perplexed evolutionary experts for decades.

A team from Azabu University believed they have cracked the code.

Two mutations in the melanocortin 2 receptor (MC2R) gene, which produces the hormone cortisol, are found in dogs.

Cortisol is a natural alarm system that is released in response to fear or anxiety.

Evolution of Dogs

Wolves scavenging leftovers thrown away by early humans on the edges of settlements are thought to be the origin of dogs.

Their descendants grew bolder and closer to the humans that continued over generations.

Humans eventually recognized the animals as natural allies and began to train them to be better hunters and herders.

Dr. Miho Nagasawa, the study's corresponding author, explained that it may have become necessary for dogs to gaze at humans for instruction and to initiate communication to build a more successful relationship during the process of domestication because stray dogs are not raised in human households exhibit this trait.

It has previously been suggested that there is a genetic component involved.

The findings of their research backed up this theory.

Ancient vs. Modern

Dr. Nagasawa and colleagues investigated the phenomenon by splitting 624 domestic dogs into ancient and modern general breeds.

Those considered genetically closer to wolves, such as the Akita and Siberian Husky, made up the ancient group.

Gun dogs, mastiffs, and Jack Russell terriers, for example, are more distantly related.

All of the participants were voluntarily recruited by their owners.

Nagasawa and his team focused on ancient dog breeds to investigate breed-related differences in social cognitive abilities.

He shared that in a problem-solving task, ancient breeds showed a lower tendency to look back at humans than other European breeds, which was due to the MC2R variants.

Changes in the MC2R gene were linked to correctly interpreting gestures and gazing at the experimenters more frequently in blood samples.

Other genes, such as those for the "bonding" hormone oxytocin and another linked to hyperactivity, showed no differences.

In the problem-solving test, the general group showed higher eye-contact behavior, indicating that both groups are capable of understanding human gestures and adjusting their responses accordingly.

Domestication

This suggested that dogs' ability to understand human commands and adapt their behavior accordingly developed early in their domestication.

The stronger tendency to stare at humans, as measured by the problem-solving test, was a desirable trait that was deliberately selected for after dogs evolved through human-selected breeding.

A grey wolf, man's first best friend, made contact with its first human companions around 33,000 years ago, somewhere in Southeast Asia.

A small pack of domesticated dogs began trotting towards the Middle East and Africa around 15,000 years ago.

The Canis lupus familiaris species arrived in Europe around 10,000 years ago, when humans began to build farmsteads, villages, and walls.

The first flocks were herded and guarded by dogs, and the outlines of the great adventure were written in DNA, Good News Network reported.