Much has been said about the history, origin and evolution of the dog There are various theories about the development of the dog as a human companion, some claim that they are domesticated wolves that evolved, while others maintain that, although part of the canid family, the wolf and the dog have different origins.
Besides, what is the reason for the variety of dog breeds that exist? How did such different physical characteristics develop, despite belonging to the same species? On our site we answer these and other questions in the following article about the dog's storyKeep reading!
Classification and origin of the dog
Determining the origin of the dog has not been easy. Before talking about its evolution, it is necessary to remember the dog classification.
- Class: Mammalia
- Subclass: Theria
- Underclass: Eutheria
- Order: Carnivora
- Suborder: Caniformia
- Family: Canidae
- Gender: Canis
- Species: Canis lupus
- Subspecies: Canis lupus familiaris
This places dogs among carnivores, that is, animals that eat meat. In turn, they belong to los canidae, specialized in hunting to obtain their food, due to the type of dentition they have. In this way, the origins of the dog go back to these first carnivores, appeared 50 million years ago
Dog Evolution
The origin of the canids dates back 50 million years, but how did the evolution of the dog take place? The first canid of which we have fossils is Prohesperocyon, appeared 40 million years ago. Similarly, 30 million years ago the first canids appeared similar to the wolf and the jackal, related to the dog. These would be originally from North America, although they developed in Eurasia, thanks to the fact that they reached the other side of the world through the Bering Strait.
During their evolution in Eurasia, these canids developed into the characteristics for which the wolf (Canis lupus) is known. This means that they were organized in herds, they hunted in groups, they stood out for their large size and their tendency to hunt at night, among other peculiarities.
The latest DNA studies have shown that the wolf, the dog and the coyote share many sequences of genetic load However, the similarity between the wolf and the dog is greater. Does this mean that the dog is an evolution of the wolf? Not really. Most related studies suggest that they share a common ancestor from which two subspecies developed, however, this original species does not exist today. For more details about the story of the dog and the wolf, see this other article: "Does the dog descend from the wolf?".
The appearance of the first dogs dates back only to 14 or 15 million years ago, in the same area of Eurasia.
Dog Characteristics
In the history, origin and evolution of the dog, the genetic changes that took place in these canids to differentiate them from wolves are notorious. In the divergence to separate from the wolf, the dog evolved in such a way that today it is possible to classify it as Canus lupus familiaris.
Among the characteristics of the dog it is possible to mention:
- Less muscle mass than the wolf.
- Smaller teeth.
- Minor brain mass.
- It is possible that the muscles of the jaws atrophied when they almost completely gave up hunting.
- They have sweat glands on their paws, while wolves don't.
- The dog's fur is thicker.
- Dogs come in a variety of sizes and appearances.
- The texture and length of the fur of dogs is much more varied than that of wolves and other canids, since the breeds have many morphological differences.
Origin of the domestic dog
Now you know that the dog and the wolf had a common ancestor, but when was the dog domesticated? As we mentioned, it is estimated that the first dogs appeared 15 million years ago, at which time they lived in much of Europe and Asia. Back then, human populations had started to grow, so it was inevitable that dogs would run into them.
It is very possible that they approached populations attracted by food scraps, and some theories state that they began to consume starchy waste produced by crops. This would be one of the theories about why dogs approached human populations, however, another points to a difference in their personalities.
One of the oldest remains in existence was found in Belgium, in the Goyet cave. Due to the area, it is considered that these first domestic dogs accompanied the Aurignacian cultureThis culture inhabited the caves of Europe and had a lifestyle based on hunting. For this reason, it is possible that dogs played an important role in the task of obtaining meat.
This possibility that dogs were used as hunters is also evidenced by engravings found in Saudi Arabia. These engravings date from 6,000 or 7,000 years ago, and show dogs carrying out hunting tasks alongside humans. Similar remains have been found in Russia, Switzerland and Germany. In this way, the domestication of the dog would take place in much of Europe, Asia and Africa.
A study published in Science Advances maintains that primitive dogs could suffer from Williams-Beuren syndrome, a genetic condition that favors the development of hypersocialibity As a result of this, the dogs that began to approach humans would be more tame and had a gregarious personality destined to please. In turn, these dogs had a better chance of surviving being fed by humans. Thanks to this, the genetic characteristics were passed on to new generations.
Other ancient cultures, such as the Egyptian, also left records of their relationship with the dog through murals. In Rome they performed tasks as guardian animals, as revealed by images contained in vessels; this would be the first time in history that dogs were seen as domestic animals, rather than just companions for the hunt. In addition, they were also used as war dogs and, in fact, the Rottweiler is among the breeds that accompanied the Roman Empire in its conquests.
This would be the origin of the domestic dog. When leaving the wild, the characteristics of the dog were adapted from the breeding and according to the needs that they had to cover in the populations of which they were part.
How did dog breeds come about?
When talking about the history, origin and evolution of the dog, it is worth asking: how were dogs created? In other words, how did the more than 400 breeds that currently exist come about? Dog breeds began with the basenji, the oldest breed in the world. From it, more than 100 current races would develop and, to a large extent, this would respond to the contact they had with humans, in addition to natural selection. Find out which are the oldest breeds in this other article: "The oldest dog breeds in the world".
In each human population, dogs began to fulfill different tasks, so they acted as watchdogs, hunters, hounds, pets, collectors of aquatic prey, among others. These activities required the development of specific skills As a result, humans placed special emphasis on breeding dogs that fulfilled the characteristics that were useful to them. In this way, certain peculiarities were consolidated until they led to the establishment of the different races.
Furthermore, from the 19th century onwards, eugenics began to be applied to dog breeding, which is nothing more than the application of studies on heredity for the improvement of certain characteristics. In recent years, this discipline has been used to obtain certain aesthetic particularities in dog breeds, even to the detriment of the he alth of the resulting dogs.
Contrary to popular belief, mestizo dogs would not be the result of indiscriminate crossbreeding between dogs of different breeds. In reality, these are dogs that have developed from natural selection, that is, without the intervention of the human hand to create specific characteristics. Thanks to this, mongrel dogs are usually he althier than breed varieties, as they rarely suffer from congenital or hereditary ailments.
Consequences of the development of dog breeds
For centuries, work has been done on the evolution of the dog by creating dog breeds that, as we have mentioned, respond to certain needs of human beings. For this, specimens of the same bloodline were crossed, hereditary he alth problems were not taken into account, nor were any of the factors that interfere in the birth of dogs more or less prone to certain diseases or anomalies. As a consequence of this indiscriminate breeding, most canine breeds, especially the oldest ones, tend to suffer from a series of genetic or hereditary pathologies. Currently, copies of the same family or with he alth problems are not crossed to prevent this from happening.
Because of all the above, mestizo dogs tend to be he althier, although this does not imply that they cannot suffer from some diseases. Consult the most common diseases in dogs and their symptoms to know them.
