Look at the dog resting at your side as you read this article or the Yorkshire Terrier that you‘ve seen in the street. French Bulldog, Pug, Chihuahua, West Highland, Golden Retriever, Pinscher… sometimes it’s hard to think that the ancestor of all these races is the wolf. It is known that the variety of breeds of current dogs is due to artificial selection by humans, but the debate is still alive when trying to answer questions about where, when, how and why it occurred domestication of wolves. Have dogs influenced our evolution as a species? Why do we have such a close relationship with them?
HIPOTHESES ABOUT THE ORIGIN OF THE DOG
Currently it is known that the ancestor of the dog is the wolf (Canis lupus), probably of some extinct species. The dog (Canis lupus familiaris) is in fact one of the two domestic subspecies of the wolf; the other is the Australian dingo (Canis lupus dingo) although it is considered wild nowadays.
The first hypotheses that attempt to explain the origin of the dog, were based on the idea that our ancestors caught wolf cubs and raised them as pets. But since domestication is a slow and long process, this belief is now ruled out. What tell us the most recent researchs?
- A research in 2002 argued for an Asian origin (China today) 15,000 years ago, based on analysis of mitochondrial DNA from more than 600 dogs.
- Another researh in 2010 placed the origin of the dog about 12,000 years ago in the Middle East, based on fossils.
- In 2013, a mitochondrial DNA analysis of prehistoric canids, modern dogs and wolves concluded that domestication occurred between 18,800-32,100 years ago in Europe, much earlier than previously thought. The dog would be then the first living being domesticated by humans, since its origin predates agriculture. This would cast serious doubts in the same year’s rechearch telling that some wolves were able to metabolize starch, and therefore the cereals of early farmers, which favored (among other things) the rapprochement between wolves and humans.
Agriculture and ranching surely influenced the evolution of the dog, but the contact between humans and wolves was when we were hunters and gatherers, before the domestication of animals more profitable (cows, sheep …). But how did it happen?
THE WOLF WAS DOMESTICATED ITSELF
The domestication of the wolf is unique because it is the only large carnivore in which we have succeeded. As reported by Science in April 2015, most scientists believe that were the wolves who approached human settlements voluntarily. Those who were less timid, more easily obtained food from the remains of dead animals left by our ancestors. Over time, these wolves survived longer and each generation was slightly different to previous, less and less fearful of humans. Humans would choose the most docile up to live with them. Wolves’ social skills and cooperation with its kind were maybe features that helped to cooperation with humans.
Over thousands of years the relationship between humans and dogs has been coevolution (one has influenced the evolution of the other and vice versa), so much to create bonds with just a look, something that we might think that is a exclusive hominid feature. When you look into the eyes of your dog the same hormone is released in both (oxytocin), the same hormone that is released when a mother looks at her son. If you also have the feeling that your dog understands you when you look at it, you smile at it, you talk to it … apparently you’re not entirely wrong.
CONSEQUENCES OF LIVING TOGETHER WITH DOGS IN HOMO SAPIENS
Althought your dog is just a pet and/or part of your family, they are now also used for almost the same tasks as those already profited early modern Homo sapiens:
- Help for hunting: dogs could track the dam because they have a better smell, pursue and harass it until we killed it if it was too big for them. In addition, it is possible that humans communicated with dogs with his eyes, making a quieter hunting.
- Search for buried or hidden food.
- Transporting objects: fossils indicate that the first dogs carried objects in its backs and pulled carts.
- Monitoring and protection against other predators, through better night vision and hearing.
- Use as alternative food if hunting was scarce.
- After the appearance of ranching, to control livestock.
The dog in turn, also made a profit from its union with H. sapiens, especially in the way of food easy to get.
An important consequence of the domestication of the wolf is that it was the starting point of the domestication of other animals. Our ancestors understood the advantages that supposed to have domesticated animals to their advantage, so the ranching revolution started about 10,000 years ago.
Furthermore, Pat Shipman, antrophologist, has published recently a paper and a book where explains the advantage that H. sapiens with dogs would have had against H. neanderthalensis, even contributing to the extinction of this species. Apparently the advantages set forth above associated with dogs, not only gave the first modern sapiens advantage to compete with other carnivores for food, scarce in full glaciation. Also they had an advantage over the Neanderthals, which had only their own means to feed. Not only disappeared with our arrival the Neanderthal population in Europe, so did the mammoths, European lions and buffalos.
The causes of extinction of the species most similar to ours, the Neanderthals, remain a mystery. The reasons are probably multiple but rarely we ask ourselves that “man’s best friend” has contributed to this. Perhaps thanks to them you’re reading this article and I’m writing it, perhaps we are here as a species thanks to dogs.
REFERENCES
- Los perros se hicieron amigos del hombre escarbando en sus basuras
- Los lobos se hicieron perros siguiendo a los primeros cazadores europeos
- Cómo los lobos se convirtieron en perros
- Historia de la domesticación del perro
- La mirada entre perro y dueño refuerza su unión emocional
- Cover photo (siberian husky) by Mireia Querol
All you need is Biology 
