The evolution of dogs

For a long time now, the history of dogs and humans has been intertwined. We evolved alongside each other and, in turn, formed a symbiotic relationship, providing for one another and helping each other out. The domestication of dogs allowed us to become much more effective as hunters. This meant we could advance as a civilisation and provide for our new companions better than ever before.

But even before we get to the domestication of the dog, and the twinning of our destinies, the history of dogs is the story of evolution working at its best.

It’s no surprise that modern dogs are largely agreed to be descended from wolves. In fact, there has been no evidence to indicate another canine contributing to the genetic lineage of dogs at any point in history

While the closest living relative to our dogs’ ancestors would be the modern grey wolf, there is a general consensus that the wolves of today have little in common with the wolves of the past.

When exactly dogs split off from their lupine cousins to forge their own genetic path is not entirely known, although there is a rough idea. In 2013, after the whole genome sequence of modern dogs was completed, it was estimated that the divergence of wolves and dogs took place around 32,000 years ago.

In terms of where this split occurred, there is still some debate, although it’s widely accepted that it occurred in Europe and Asia.

It’s believed that the domestication of the dog may have occurred at the same time as the split. American academics Dr Brian Hare, director of the Duke Canine Cognition Center, and Vanessa Woods, a research scientist at Duke University, believe that rather than following Darwin’s ‘survival of the fittest’ instinct to stay alive and evolve, wolves and early dogs instead followed a ‘survival of the friendliest’ instinct.

In an adaptation of their book, The Genius of Dogs, published in the National Geographic, the pair say: “Most likely, it was wolves that approached us, not the other way around, probably while they were scavenging around garbage dumps on the edge of human settlements. The wolves that were bold but aggressive would have been killed by humans, and so only the ones that were bold and friendly would have been tolerated.”

These wolves and wild dogs would eventually become tame and trained for hunting, guarding and eventually companionship. As time wore on, the domestication progress would mark out these dogs from their wolf brothers and sisters in ever more distinct ways.

‘Friendliness caused strange things to happen in the wolves,’ Hare and Woods say. ‘They started to look different. Domestication gave them splotchy coats, floppy ears, wagging tails. In only several generations, these friendly wolves would have become very distinctive from their more aggressive relatives.’

The general scientific consensus is that the domestication of the dog dates back to before the founding of human agriculture (11,000 years ago) by at least a few thousand years. The domestication of the dog at this time is also supported by the fact that humans were hunter-gatherers.

If an animal was to keep up with humans during this time, it would need to be able to survive on meat, be able to hunt and be capable of travelling large distances. For these reasons, it’s easy to see why the dog was one of the first animals domesticated by humans.

As human civilisation settled down and became a more sedentary race, other animals soon followed the dog into domestication, but that didn’t mean we used dogs any less. If anything, we used them more.

While dogs continued as hunters, they also evolved to guard us and our herds and help us eliminate pests. We have even used them in war since at least 700 BC.

It’s impossible to overstate the impact that the domestication of the dog has had on human civilisation. Archaeologist and geneticist Greger Larson said: ‘Remove domestication from the human species, and there's probably a couple of million of us on the planet, max. Instead, what do we have? Seven billion people, climate change, travel, innovation and everything.

‘Domestication has influenced the entire Earth. And dogs were the first. For most of human history, we're not dissimilar to any other wild primate. We're manipulating our environments, but not on a scale bigger than, say, a herd of African elephants. And then, we go into partnership with this group of wolves. They altered our relationship with the natural world.’

Man’s best friend, indeed.

As both humans and dogs are emotionally intelligent animals, it’s only natural that throughout our march through history together, we became fast friends along the way. In fact, the science behind this is even more fascinating.

When humans look into each other’s eyes, we recognise the sentience and emotional intelligence that we have, which then causes the body to release a hormone called oxytocin. This helps us to form emotional bonds. The same phenomenon also happens in both humans and dogs when looking into each other's eyes – not only do we live together, but we understand each other.

The concept of pet ownership itself is believed to have risen to prominence during the reign of several ancient civilisations, most notably the Egyptians and their deification of cats. Dogs were no different, for as we became less dependent on them for survival, they became status symbols and, most notably, the ruling classes of ancient Greece, Rome and Egypt all kept dogs as pets.

This isn’t to say that the number of pets was consistently on the rise. In fact, there were a few periods in history that saw a decline. When witchcraft became the focus of the church, the victims were often the elderly and isolated people in remote areas who kept pets for companionship. This is because an animal familiar, or animal possession, were all considered aspects of Satanism, which sadly caused an overall decline in pet ownership. How things have changed!

Luckily, this decline in pet ownership was short-lived and as we moved towards a more ‘civilised’ world, it gradually became more accepted, although it still wasn’t quite the form of pet ownership we know today.

Modern pets, as we know them, did not rise to prominence until the late Victorian period. This era saw the mass adoption of modern dog-breeding techniques, spurred on by Charles Darwin’s On the Origin of Species, which was humanity’s breakthrough understanding of natural selection.

During this period, dog ownership and specific breeds skyrocketed, and the idea of keeping a pet for something other than a specific job became a much more widely accepted occurrence. It was still some time before pet ownership was something for everyone, however. The lower classes, in particular, were seen to be improper if they owned a pet, as that meant they were not attending to their regular duties as efficiently as they should be.

Luckily, as time has gone on, we have realised just how great dogs are, regardless of our backgrounds and class. We’ve effectively evolved our symbiotic relationship into one that focuses primarily on care and attention. Dogs are now seen as an integral component of the typical family unit, and enjoy many protections under the law.

In today’s society, dogs still have a huge amount of work to do, as guide dogs, emotional support animals, guard dogs and even still in the military. Yet the vast majority of us are just content to have a furry friend to come home to at the end of the day, who loves us in the same way that we love them.