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From apex predator to adorable pooch: how food brought dogs and humans together

It wasn’t until the middle of the 19th century that humans unlocked the secrets of genetic inheritance. But as the humble dog proves, our ancient ancestors living tens of thousands of years ago had at least figured out that certain behaviours and characteristics could be bred into wolves. Before there were farms, cities, or anything we might consider a hallmark of civilisation, there were good boys (and girls).

The timing, cause, and even location of this domestication are all uncertain. Genetic research suggests that dogs split from their wolf ancestors some time between 27,000 and 40,000 years ago, but scientists debate whether this domestication first occurred in Europe or Asia, or even independently on both continents. Regardless of the answer, the European lineage has mostly vanished; modern dogs trace their ancestry to wolves in Asia.

Strange bedfellows
Though wolves are fearsome, they are frightened of people. So how did these creatures, naturally inclined to avoid us, come to share our homes? It is easy to imagine a group of hunters retrieving their spears or arrows from the side of a recent kill, perhaps a deer, and a pack of wolves emerging in the hope of scavenging something from the body. A hunter removes a piece of flesh and throws it to one of the braver animals as it cautiously steps closer. Perhaps the pack of wolves are even known to the hunting party, perhaps they have followed them before and grown accustomed to their presence.

Others suggest that wolves scavenged around human camps and fed off their waste, becoming increasingly accustomed to people over time and eventually tame enough to control. Recent research, however, suggests that humans and wolves may have shared the same food more openly. Humans have a limit on the amount of protein their bodies can handle, whereas wolves can survive off lean raw meat alone. As such, humans would have likely had more meat in their camps than they could finish. If this is true, our two species may not have competed much at all and would have had a much easier initial relationship.

Either way, once humans started interacting with wolves, they would have recognised their potential as hunters and guards, due to their deep, genetically ingrained sense of loyalty. Over time, a form of natural selection and genetic drift caused by human activities moved subsequent generations away from their wolf relatives, especially with the selection of wolf pups that were more socialised towards humans. Eventually, humans began to exert control over the proto-dog’s mating relationships to the point where the wolf became a dog.

Since then, dogs have spread to every corner of the world and followed human migration into even the most inhospitable and demanding environments. Today, there are about 400 recognised dog breeds in the world, most of which are the product of Victorian enthusiasm for breeding increasingly specialised characteristics into their dogs, from dachshunds to German shepherds. Such is the impact of human activity on dogs that we now share as many as 360 medical conditions with them, including dementia and epilepsy.

It’s in the genes
You can tame a chimpanzee, or a dolphin, but that is drastically different from what we’ve done to dogs. Where taming seeks to condition behaviours and modify an individual, domestication involves the permanent genetic modification of certain traits across multiple generations. It is not focused on a single or a few traits, either, but a suite of traits including changes to reproductive cycles, morphology, and behavioural changes. And we’ve done all sorts: dwarfism, gigantism, wavy or curly hair, shorter or longer tails and floppy ears – not to mention behavioural changes that may affect the animal’s mood, emotions, and social tolerance towards humans.

The significant changes to metabolism and morphology that accompany behavioural changes in domesticated species also tend to lead to a dependence on humans for food and shelter. But one of the most significant differences between dogs and their wild ancestors is their ability to eat a wider variety of foods, especially carbohydrates.

Depending on the breed, dogs have four to 30 copies of the gene Amy2B, which produces amylase, an enzyme that helps break down the starch in the intestines. This means that dogs are significantly better at digesting starch than wolves, who only have two copies of this gene. “This genetic shift happened about 7,000 years ago,” says Clare Hemmings, scientific communications manager at pet food manufacturer Royal Canin. “And would have allowed dogs to adapt to eating carbohydrates and vegetable proteins alongside humans when we started to settle and farm.”

Dogs also have a better ability to break down maltose into glucose, another important step for dealing with starch. Other enzymes in the lining of their intestines then break down these simple carbohydrates so they can be absorbed and used in the body.

Not a wolf, not yet a human
But while dogs can enjoy a more varied diet than wolves, it’s important to remember that this does not make them people. “There is a large disconnect between what we would fancy eating and what animals need to eat,” says Hemmings. “Dogs are dogs, their drives are not the same as ours.” In fact, she says, dogs “have very few tastebuds compared with humans – 1,700 compared with our 9,000”. This means that dogs are driven by the need for the correct nutrients, rather than the taste of food.

The genetic variation between breeds also impacts what sort of food a dog needs. For instance, there are breeds more prone to gain weight, such as labradors, which are genetically prone to carry more fat cells and require lower-calorie food to help them maintain a healthy weight. Similarly, golden retrievers are known to suffer from joint disease, which can be aggravated by diets that are too rich in calories or calcium, so they need food that will help their bones remain healthy and develop properly.

That is why Royal Canin has developed tailor-made formulas to deliver the nutrition that your best furry friend needs, whatever their size, breed or age. That way, you are not only providing your dog with the food it deserves, but also continuing to honour a relationship that is tens of thousands of years old.

Shop the Royal Canin range and find the perfect food for your dog at royalcanin.com