How humans have changed dogs over thousands of years

There are hundreds of breeds today, but the diversity of dogs emerged long before modern selective breeding began.

Genetic research shows that several major dog lineages already existed around 11,000 years ago. This means that dogs began to diverge significantly as far back as the hunter-gatherer era, when humans were only just settling into new territories and ways of life.

As people spread out, dogs found themselves in vastly different environments — from the freezing Arctic to the humid tropics. In each case, they had to adapt to the climate, the food available and the tasks set for them by humans.

In the Arctic, dogs became part of the technology of survival

The bond between humans and dogs became particularly close in the north.

Arctic dogs helped to transport goods, travel across snow and ice, and take part in hunting. Genetic data shows that a specialised line of sled dogs existed as far back as around 9,500 years ago.

These animals were stocky, could withstand the cold well and were capable of working for long periods in harsh conditions. Archaeologists have also found signs of strain on their bones, characteristic of pulling heavy loads.

In some northern regions, humans and dogs even shared a similar diet, including marine animals. This shows just how closely their lives were intertwined.

In Tibet, dogs have adapted to low oxygen levels

Another striking example is the Tibetan Plateau.

At high altitudes, the air contains less oxygen, and it is difficult for ordinary animals to survive there. However, local dogs have developed genetic traits that help them cope better with such conditions.

Similar adaptive mechanisms are also known to occur in people living in Tibet. In both cases, genes linked to the body’s response to low oxygen levels play an important role.

That said, it would be incorrect to claim that humans and dogs have undergone identical changes. They have adapted to the same environment, but have done so through their own biological mechanisms.

In the tropics, entirely different qualities were required

In the hot forests of South America and South-East Asia, dogs were required to be agile rather than strong.

There, they helped with hunting in dense vegetation, tracked down animals and moved quickly across difficult terrain. A more compact body and lower weight may have been an advantage in such conditions.

People also deliberately selected puppies with the required qualities — a keen sense of smell, stamina or the ability to work alongside the hunter.

Gradually, local breeds of dog developed that were well suited to specific tasks.

Some dogs were even bred for their fur

Dogs were not always used for hunting or carrying loads.

On the north-western coast of North America, some indigenous peoples bred small dogs for their fur. This was used to make fabrics and ceremonial blankets.

In other cultures, the dogs’ appearance, behaviour or role in rituals were important. Their development therefore depended not only on the climate, but also on human traditions.

Diseases could also have influenced the spread of dogs

In some regions, it was not the climate but infections that hindered the spread of dogs.

In tropical Africa, the spread of dogs may have been hindered by diseases carried by insects and ticks. Such infections reduced the animals’ survival rates and may have limited their numbers.

This helps to explain why dogs became commonplace very early on in some parts of the world, whilst in others they remained rare for a long time.

Many ancient dog lineages have disappeared

Modern dogs are not always direct descendants of the animals that lived alongside ancient peoples.

Genetic research shows that many ancient lineages have disappeared or have been largely displaced by breeds of European origin that have spread across the world in recent centuries.

However, in some regions, traces of ancient populations have survived. These enable scientists to reconstruct the migration routes of humans and the history of their relationship with dogs.

Who changed whom — humans the dog, or the dog the human?

The origins of domestic dogs remain a complex subject.

It was most likely not a single, brief moment when humans suddenly ‘domesticated the wolf’. The process may have taken a long time and involved a gradual rapprochement between animals and humans.

That said, the idea that wolves and humans were originally completely ‘equal partners’ remains an interpretation rather than a proven fact. Genetic research shows that the origins of dogs were complex and involved several ancient populations and movements alongside humans.

Why this is important

The history of dogs demonstrates just how profoundly humans are capable of altering other species — even long before the advent of modern selective breeding.

Dogs evolved to suit the local conditions and people’s way of life. In some places, strength and stamina were valued; in others, speed, hunting skills or a thick coat.

But these changes were not solely due to human influence. Climate, altitude, disease and available food also influenced which dogs were able to survive in a particular region.

Source

This article is based on the book by archaeologist Peter Mitchell, *First Dogs: Hunter-Gatherers and Their Canine Companions from Prehistory to the Present*, which brings together archaeological, genetic and ethnographic data on the relationship between humans and dogs spanning thousands of years. Some of these findings are supported by ancient DNA research, which reveals the early diversity of dogs, the development of Arctic sled dog breeds and the adaptation of high-altitude dogs.

Book: Peter Mitchell. *First Dogs: Hunter-Gatherers and Their Canine Companions from Prehistory to the Present*.