The dog, a very docile wolf: let’s discover the origins of the species – The dog is the animal that most easily happens to meet, see, touch. It is around us, in our homes, everywhere and for millennia.
Whether our family has one or more or does not have one, the dog is still a very widespread presence in our society and it is practically impossible not to deal with it, by choice or by chance.
And yet, science has only recently begun to seriously study dogs, discovering fundamental things to understand who our fantastic and indispensable life partner is and why!
Nonetheless, or perhaps for this reason, because of the habit of seeing it forever, it is an animal that, in reality, we often know only superficially.
We know many things about “him”, it is true, but they are usually generic knowledge: he barks, he is the “guard”, he generally loves cuddles; sometimes it growls or tries to bite, other times it saves our lives … yeah, but “who is” really this creature?
And why is it an integral part of our society and of the lives of many of us more than any other non-human living being?
Let’s find out together. Since knowing “who is” the dog is the first step necessary to try to understand how he reasons and why.
1. The first hypotheses. Konrad Lorenz thought that …
Before the advent of genetics, which dates back to a few decades ago, the only sources available to hypothesize the origin of the dog were the archaeological finds and … the similarity with other similar species.
It was on the basis of these conjectures that Konrad Lorenz, the famous father of science who analyzes the behavior of animals, ethology, hypothesized that some breeds of dogs descended from the jackal and others from the crossing of the former with the wolf.
This hypothesis circulated at least until 1975, when Lorenz himself admitted to having probably made a mistake and to believe, at the time of his course correction, that the dogs were all descended from the wolf, to be precise, the subspecies of the gray wolf spread from the Middle East to Asia, the Canis lupus pallipes.
Again, however, it was a conclusion based on decades of observations and reflections, not on scientific evidence, because the tools to find them were lacking.
That Lorenz’s intuition was substantially correct has been shown only in more recent years, thanks to the analysis of DNA, that is, of that tiny component that is the basis of every life on Earth.
Dog and wolf are interfertile: the former is a subspecies of the latter. As proof of the close relationship between the wolf and the dog, the fact that these two species are interfertile, that is, they can mate, and still do so in many areas of the world including Italy, and that their children are in turn able to reproduce .
A very interesting particularity. In fact, the same thing does not happen when two species are very similar but not to the point of being genetically almost “superimposable”.
For example, there is only a meager 1 percent difference in genes between us and chimpanzees, yet … we could never reproduce. That minimal difference matters a lot, then.
Horses and donkeys can mate and have children instead, but the latter are sterile. Dogs and wolves, by contrast, have complete reproductive success. In other words, from this and many other points of view the two species are practically identical.
Indeed, the dog is now considered by the vast majority of scientists to be a subspecies of the wolf, so much so that its official name has changed for years: from Canis familiaris, i.e. domestic dog, a Canis lupus familiaris.
In short, in our living room … there is a wolf! Or rather, its domesticated and changed version, often in an incredible way, both in morphology and in size. But always wolf remains …
2. Scientific evidence: DNA revealed the origins of the dog
A study conducted in 1997 by a team led by Robert Wayne at the University of California in Los Angeles gave scientific confirmation of Lorenz’s intuition.
Analyzing the mitochondrial DNA (i.e. that transmitted from mother to children) of 140 dogs of 67 breeds and that of 162 wolves from 27 different locations distributed between Europe, Asia and North America, 5 coyotes (Canis latrans), 2 golden jackals (Canis aureus), 2 black-backed jackals (Canis mesomelas) and 8 Siemen jackals (Canis siemensis), the result was that all the dogs had the wolf’s DNA as a predominant component, to the point that there is greater genetic proximity between the two species that between the wolf and the other wild Canids.
Conclusion: the dog is descended from the wolf and only from the wolf. Yeah, but which one? And how long ago did the species change? Basically: how long has the dog appeared on Earth? And, in parallel, being an animal become domestic, how long has our cohabitation with him lasted? Today, new discoveries provide fascinating answers.
How and when did the dog domestication take place? Genetically confirmed that the dog’s direct ancestor is the wolf (Canis lupus lupus), today it is believed that domestication took place through a “natural” process: the less fearful wolves would begin to follow groups of nomadic hunters, moving with them in search of new prey and feeding on the many waste and leftovers left by men at the edges of the camps.
At the same time, men would begin to appreciate the presence of wolves, bringing them closer and gradually integrating them into the human community, feeding them, taking care of them and being supported by surveillance and hunting activities.
When did this process occur? Until some time ago it was believed that the domestication of the dog had occurred about 17 thousand years ago. Recent discoveries have, however, shed new light on the subject, allowing the whole process to be backdated.
In 2012 in Předmostí, in the Czech Republic, canid skeletons dating back to 27 thousand years were found: in particular three of these, according to scholars, belonged to real dogs and were characterized by shorter bones and muzzles and with a wider palate than that of wolves.
The skeletons of dogs found in the Cave of Razboinichya, in the Altaj Mountains in Siberia, in particular remains of perfectly preserved jaws and teeth, they date back to 29 thousand years ago. Even older, dating back to 32 thousand years ago, are the dog skeletons found in the Goyet Cave, Belgium.
All these discoveries therefore show that domestication began very early and that the first domestic dogs joined the modern man already in the years of his “overlap” with the Neanderthal man.
Not only that: the particular tombs found in Siberia show that dogs were held in high esteem and buried according to very specific rituals.
3. The genetics of domestication
But how come some ancient wolves would gradually approach humans until they even changed their morphology, in addition to mitigating the behaviors of the predators they were, and turning into dogs?
Probably, the cause is genetic: a particular gene had to be present in the DNA of these dog progenitors, the one that pushes us to explore novelties and counteracts the innate fear of what is unknown, typical of almost all wild animals.
Proof? In the 1950s, a Russian geneticist, Dimitry Belyayev, began to select silver foxes for commercial purposes for fur production. But his real goal was another: to demonstrate that genetics and behavior are linked.
So for twenty years Belyayev had only the less “wild”, that is, less fearful, foxes reproduced among them. The result? Barking foxes, who follow those who feed them, seek cuddles, have different colored eyes, spotty fur, sometimes semi-erect ears and double annual reproductive cycle. Just like dogs.
Belyayev managed to prove his theory and, without knowing it, went much further: he discovered that the “domestication gene” also changes morphology, not just behavior. The same probably happened over thousands of years to wolves who were not afraid of humans.
Nutrition also reveals traces of domestication even in its bowl! In a recent study appeared in the scientific journal Nature, a group of researchers from the University of Uppsala, Sweden, has published the results obtained from the reequencing and comparison of the entire genome of the dog and the wolf.
Researchers identified 3.8 million genetic variants and isolated 36 genetic regions that appear to have undergone long selection during the dog domestication process.
Nineteen of these regions contain genes important for brain function, ten concern the genes that govern fat metabolism and others, in particular, of starches.
This genetic mutation intervened to encourage the progressive change in the feeding of dogs which, living more and more with humans and feeding on what our species offered them, went from an exclusively carnivorous diet to a more varied diet, also including starchy foods that the wolf did not consumeobviously, and for whom his stomach is not predisposed.
4. Other evidence from the excavations
As mentioned, ritual burials of large dogs still very similar to wolves were found in Siberia, lying in their tombs with all honors: deer tooth collars, bones of large herbivores and horns of ungulates are the objects found on and around skeletons.
One of these dogs even had a sort of “ball” in its mouth, a carefully crafted spherical artifact. We are talking about hunter tribes of 7-9 thousand years ago.
An ancient culture that evidently reserved great importance to the dog, so much so that it was considered worthy of a burial quite similar to those found in the same places and dedicated to human beings.
Even in these tombs, in fact, there were artifacts and ornaments similar to those found in the burials of dogs. In addition, one of the skulls of these dogs revealed a previous injury to death: a head fracture that was successfully treated, so much so that the animal lived several years before he died and was buried with all honors.
All this presupposes a very long coexistence of these primitive populations with their dogs, centuries during which a deep relationship of friendship and affection developed and, consequently, also skills related to breeding, selection, care. Stone Age dog lovers.
Last but fundamental detail: the DNA analysis on the remains of these ancient Siberian hunting dogs revealed their descent from a species of extinct wolf. maybe the wolf of Taymir. But will he be the “grandfather” of dogs?
On May 21, 2015, a team of Swedish researchers published an interesting study in the scientific journal Current Biology, born from an apparently insignificant discovery: a wolf jaw found in Siberia and dated 34,900 years ago.
Genetic analysis has revealed that it is an animal slightly different from the Eurasian wolf, a social predator extinct for thousands of years, called “Taymir Wolf” from the name of the region where the find was found, but whose genes are present in significant percentages in some breeds of dogs, the Siberian Husky and the Greenlandic in particular.
Two of the oldest breeds in terms of selection, bred for millennia by the semi-nomadic hunter populations of Siberia first and then the Arctic. Two breeds that also represent the very embodiment of dogs called “Spitz type”, basically the most wolf-like wolfs. The same genes have also been found in today’s Eurasian gray wolf.
Based on these findings, now some researchers believe that the evolution of the dog may have followed a different path than what was hypothesized, that is, that it started about 27 thousand years ago from a common ancestor of the Eurasian wolf and the dog, and that it continued on different roads to date.
With our decisive contribution, obviously much prior to the birth of permanent human communities. The dog, in all likelihood, has been our life partner for many thousands of years more than estimated so far. Almost double. And this has other, incredible implications: we and the dogs have evolved together.
In the photo below, the jaw of the Taymir wolf found in Siberia is dated more than 30 thousand years ago: it belongs to an extinct wolf whose genes are present in gray dogs and wolves.
5. Common evolution and the human-dog understanding
Have you wondered why the dog was the only living being to become an integral part of our world, anywhere on the Planet, and of our life, including its emotional component, therefore the most intimate and sensitive of our personality?
Have you ever thought about why the dog has the innate ability to decipher our body language, down to the smallest detail, and even to learn perfectly and without any specific training the meaning of many words that we pronounce in his presence, without necessarily addressing us to him?
Why is there this incredible spontaneous harmony between a large part of our species and dogs? How come this never happens at such profound levels with other living beings? The amazing answer could be the “Co-evolution”. A cohabitation almost 30 thousand years long would have paid off.
From the study of the human genome, that is, of the set of genes that make up our species, and of the canine genome, it seems that some genes have evolved in parallel, a sign of probable common selective pressure.
In other words, we shared the same environment, the same life, the same risks, the same defeats and the same victories for thousands of generations, so our evolutionary response, mentally and emotionally, was shaped by identical factors.
How could we and the dogs not have been in natural harmony? We are the product of the same culture, of the same history, of a path that led us, together, from caves to space. In the deepest and most real part of our being “human”, we are also dogs. And even deeper, as social predators who together kill to feed and strenuously defend the pack and the territory, we are also wolves.
If we and the mysterious prehistoric wolf from which the dog came, we had not met so long ago, when we were only creatures devoted to survival, hunters and preys at the same time, and if we had not made this plurimillennial pact, today we would be nothing but banal evolved monkeys. Let’s keep that in mind, every time we pet a dog.
The relationship between man and dog may have been favored by one of our anatomical details: the eye sclera. In our species, unlike the other Primates, the white part of the eye is much larger and this allows us to understand in which direction a man is looking even if he is far from us. Children learn to follow the gaze of others already between nine and fifteen months, it is an innate behavior.
Michael Tomasello, researcher at the Max Planck Institute for Evolutionary Anthropology in Leipzig, confirmed this by comparing the visual skills of a group of children and Primates. Each of them was placed in front of a researcher who initially raised his head to the ceiling and later only moved his eyes upwards.
The Primates in turn raised their heads only in the first case: they were unable to follow the movement of the eyes alone. Well, science has discovered that, like children, dogs are also able to follow man’s gaze, focusing on the same point. This is why, for example, the man-dog hunting combination works so well.
Scholars have not yet been able to establish when this anatomical change really took place: if it were possible to demonstrate that the mutation occurred precisely in coincidence with domestication, this would undoubtedly have favored and accelerated the construction of the friendship between man and dog , making mutual communication easier.
The white sclera would have been, in conclusion, an additional factor that allowed the rapid affirmation of modern man thanks to the enormous advantages deriving from the collaboration with the dog. Perhaps it is true, after all, that God is in the details …
Curiosity: The meaning of kisses
When a dog kisses us in the area around the lips, it does nothing but repeat the behavior that the wolf cub adopts to obtain food from the adult, who regurgitates it on command.
Wolves raised with humans also exhibit the same behavior but neither the dog nor its progenitor actually expect to be fed.
Simply, and wonderfully, they are communicating their dependence on us, their affection, their being “puppies” towards us. An attitude of absolute pacification.