How did the domestication of the dog occur during prehistoric times?

How did the first dogs appear, starting with the domestication of the wolf? Let's see.

The dog is man's best friend, but it has not always been so. At some point in prehistoric times, humans and wild wolves established a bond that would grow stronger over thousands of years.

This phenomenon is the domestication of the dogwhich has involved its progressive evolution from the wild primordial ferocious wolves to all the canine breeds we know today.

The scientific community has tried to find out how, when and where this process first took place, putting forward several theories based on the genetic findings of different fossils and modern breeds. Let's see it below.

When did the domestication of the dog begin?

The domestication of the dog was a gradual process, of which the scientific community has not yet clarified where, when and how it occurred.The scientific community is still unclear as to where, when and how it occurred. What is known is that the modern Canis lupus familiaris is a descendant species of a primordial wolf, as is the case with gray wolves. At some point in evolutionary history, these wolves and mankind's best friends separated, establishing themselves as two different species. This event must have occurred between 15,000 and 40,000 years ago.

Scientists have been trying to figure out how an animal as dangerous and ferocious as the wolf could, at some point in its existence, become the friendly species that can be found in many homes. species that can be found in many homes. Many genetic studies have been carried out around the globe, analyzing modern breeds and bone remains found in Asia and Europe to establish when the domestication of the dog took place.

The problem is that it has not been possible to clarify the matter. The dates proposed by the scientific community vary widely, and the fact that it is not clear whether it was in Asia, Europe or somewhere in between does not help. It has been agreed that the first domesticated wolves must have lived between 15,000 and 40,000 years ago.

Did it happen several times over the years?

One of the most shocking recent discoveries has been that the dog was attempted to be domesticated on more than one occasion. Scientists have analyzed the mitochondrial DNA of 59 remains of different dogs that lived in Europe, ranging in age from 3,000 years (around the time of Ancient Rome) to 14,000 years. In addition, it was possible to analyze the entire genome of a dog that lived 4,800 years ago and was buried near a prehistoric monument in Ireland.

The genome obtained from these dogs has been compared with that of modern breeds of their congeners and with wolves, suggesting that the dogs were domesticated in Asia around 14,000 years ago.suggesting that the dogs were domesticated in Asia some 14,000 years ago. Their lineages split in two, in the period from 14,000 years ago to 6,400 years ago, forming large populations: one in the Far East and the other in Eurasia.

But, despite this, other fossils older than these have been found in Europe. This finding had given rise to positions, such as that of Thalmann's group, that dogs arose in Europe and spread from there. However, others have found that this branch, which is supposed to have been the first dogs in history, eventually became extinct at some point, being replaced by Eurasian breeds.

From these findings it is possible to extract that, in fact, the research that had asserted that dogs had arisen in Europe or Asia was certainly correct.. That is to say, it is not that today's dogs are descended from all these primitive populations, but it is true that the domestication of the dog occurred in various places at different times in history.

Moreover, this allows us to have a more open mind, since it allows us to accept the idea that there were more than two domestications, fighting against somewhat recalcitrant positions that had been established in the scientific community regarding this issue, especially among European experts.

How did they become our best friends?

The questions of when and where dogs were domesticated have not yet been fully answered, but a third question remains: how did prehistoric man manage to domesticate the fierce wolf?

One of the theories that has been put forward is that of helplessness.. A badly wounded wolf was found by some prehistoric human who, instead of killing it, took care of it. The wolf, grateful for the treatment, began to be more tame, accepting the food of his new friend and, soon, began to have a more protective and friendly attitude towards humans, behavior that must have been transferred to other conspecifics. But this explanation is too simplistic and has little scientific support.

Another theory holds that prehistoric humans managed to capture wolf cubs, kept them as pets and gradually domesticated them.. This event may have occurred around the time of the rise of agriculture, some 10,000 years ago. The oldest fossils of what appear to be dogs date back 14,000 years, but fossils almost twice as old have also been found of, apparently, something resembling a dog or something that must not have been a primordial wolf.

Thanks to more recent genetics research, it has been suggested that the date of dog domestication must have occurred earlier, lending support to a new theory. It must not have occurred because a wounded wolf became tame, nor because pups were abducted.

The most plausible explanation is that primitive wolves, as with any other species, showed personality differences, with some being more friendly and others more aggressive. The friendlier ones were closer to humans, without harming them, which must have aroused a less defensive attitude on the part of the prehistoric wolves..

Seeing that the beasts were beneficial for their protection, especially for predators of fields and crops, humans gradually accepted the company of wolves and eventually domesticated them.

This domestication involved changes in appearance, making them more "lovable", in Brian Hare's opinion.according to Brian Hare, one of the scientific experts on the subject. The wolves began to develop more human-friendly characteristics, characteristics that must have occurred after only a few generations, such as floppy ears, more chest fur, curly tails and the sensation of smiling when they are breathing through their mouths.

But it is not only the physical aspect that changed over the generations. The wolves' own behavior became increasingly oriented toward satisfying humans.. They became even more agreeable, focusing their attention on their new owners and acquiring a very protective behavior towards humans.

Genetic evidence for the theory

A study conducted by evolutionist Bridgett M. vonHoldt of Princeton University provided genetic evidence in support of this theory. Dogs, compared to wolves, show higher levels of motivation to seek out interactions with humans.. This would demonstrate that there is a genetic tendency, shaped by the passage of thousands of years, to encourage beneficial behavior toward the human species.

Von Holdt found that there are regions in the genome of dogs and wolves that are shared, only that there are modifications in dogs. These modifications in the but regions of the human genome cause Williams-Beuren syndrome, a condition in which the person is extremely trusting and very friendly.

How much have these animals changed?

Although the exact origins of how the long-lasting relationship between humans and dogs was formed, it has been discovered how each species has changed over time. has been discovered how each species has changed over time.. The differences between dogs such as pugs, dachshunds and poodles are very obvious compared to wolves. But, in addition to this, and as we have already mentioned, there are differences in personality and, what is most striking, their bond with humans and their hormonal response.

Research has found that the bond that has been favored between dogs and humans, learning to work with humans, has been detrimental to teamwork between dogs. Their lifestyle and pack-working mentality has been reduced compared to wolves, even catching wild dogs. However, they seem to have developed the ability to solve problems by asking their human owners for help.

An example of this is the experimentation on problem-solving between dogs and wolves. For example, if a problem is set to be solved, such as opening a box by means of a puzzle, dogs and wolves respond differently. Wolves will, as a rule, try to obtain the solution by trial and error. Dogs, on the other hand, first stare at what they have to solve and then turn around and look into their owner's eyes, as if asking for help. This is a very interesting interspecific social behavior that can hardly be observed in other species.

And speaking of looking into the eyes. It has been shown that the brains of dogs and humans are synchronized. If a dog and its human owner look into each other's eyes, the brains of both begin to secrete oxytocin, a hormone linked to maternal love and trust. Oxytocin is not unique to dogs and humans, as it is found in other species.Oxytocin is not unique to dogs and humans, as it is found in other species and has a very important function in establishing bonds between mother and offspring or with peers, but the case of dogs with humans is something that has not been found in other species.

Of course, how, when and where the first human-dog bond was established has been of great importance in history. has been of great importance in the evolutionary history of mankind.. A life without dogs is unthinkable, something that might well have happened if their great-great-grandparents (to spare us millions of "tartars") had not had the brilliant idea of approaching a group of hunter-gatherers. What would life be like without dogs? Desde luego, demos gracias a lo caprichoso de la evolución de que los hicieran así.

Referencias bibliográficas:

• Thalmann, O., Wahlberg, N. (2013) Complete Mitochondrial Genomes of Ancient Canids Suggest a European Origin of Domestic Dogs. Science. DOI: 10.1126/science.1243650.
• B vonHoldt, J Pollinger, D Earl, et al. (2012) Identification of recent hybridization between gray wolves and domesticated dogs by SNP genotyping. Mammalian Genome 12 (1-2), 80-88
• M Thompson, B vonHoldt, S Horvath, M Pellegrini (2017) An epigenetic aging clock for dogs and wolves. Aging 9(3), 1055-1068.
• MacLean, E. L., et al. (2017) “Individual differences in cooperative communicative skills are more similar between dogs and humans than chimpanzees.” Animal Behaviour, vol. 126, pp. 41–51. Scopus, doi:10.1016/j.anbehav.2017.01.005.