wolf is the ancestor of the dog. It can live for 15 to 24 years under artificial breeding, while the dog can live for only 7 to 12 years. It stands to reason that wolves live in the wild, far away from humans, and their numbers are at stake because their habitat is infiltrated and killed. So what makes wolves live longer than "greenhouse flowers" dogs in harsh environments?
The factors affecting life expectancy are nothing more than survival and reproduction. We look for reasons from these two aspects.
Survival and reproduction
wolves are highly social animals and have an extremely strict hierarchy. Reproductive conditions are reached around 2 years old, and you need to find a mate and establish a territory before breeding. They will disperse wolves (packs) that are fighting for territory and accept wolves (packs) that are willing to surrender. In short, the head wolf is more excellent and stronger. Only it has the right to reproduce in the wolf pack. This means that the genes of the offspring are constantly selecting the best from the best, a natural process of survival of the fittest.
If you carefully observe the Chinese Rural Dog, it is a wild dog that grows naturally. You will find that it has the following characteristics:
longer nose : used for breathing, exhausting and eating. If the nose and mouth are shortened, the overall length of the teeth will become shorter (poor eating efficiency), lower heat rejection efficiency, and more difficult breathing .
Wide skull: can store a larger brain capacity. The narrower brain capacity of some modern species shrinks greatly, which not only makes them stupid, but also hinders the development of the cranial nervous system, leading to neurological diseases.
Pointy ears: prevents ear infections. If the ears are soft, it is not conducive to air circulation and it is easy to "harbour" bacteria and cause inflammation.
Larger hip bones: originates from long-term exercise and is more suitable for exercise. Most of the dogs nowadays are kept in captivity at home. Even the strong dog, the German Shepherd, still has hip dysplasia.
has a more even body shape: evenly distributes the weight of the body, reducing body wear. The above negative example of
can correspond to a large number of purebred dogs today. In general, the pastoral dog is closer to the wolf, and it retains a large number of survival advantages passed down from its ancestors. The
Country Dog is an ideal breed evolved by nature based on the physiological needs of dogs in the modern human living environment, but it is not an ideal breed for humans. Different people have different ideal breeds. For example, the English Bulldog can't breathe if it doesn't pant, and many newborn bulldogs need a Caesarean section, and the female dog can't give birth at all. There are also dog breeds with white coats that often have neurological defects, some will have subtle behavioral abnormalities, severe deafness and even premature death.
Generally speaking, working dogs receive more exercise. First of all, they need to go through screening and testing, and then go through long-term training and later work. To paraphrase half a sentence, fall in love with a good dog, but unfortunately there is no grassland in my home. Many like "champion dogs" and "pure blood", but inbreeding in a small area, or even backcrossing, is the most deadly. Some excellent genes of
can be passed down through these means, but recessive disease genetic genes will also be expanded in this way, or even become visible. Some excellent breeders can avoid some of the more common disease-causing genes by means of genetic and variety screening. However, the most frightening thing is that "pure blood" and "championship" hide undetectable chronic health problems. It is inherited from generation to generation, thereby shortening life expectancy imperceptibly.
When humans continue to pursue purebreds and championships, a large number of pets will reproduce in a smaller genetic circle. A typical example is the poodle. After genetic testing, scientists have found that some pure standard poodles have actual genes. The above originated from the earliest 7 dogs. Narrowing the scope of the population gene pool means the loss of genetic diversity, leading to the emergence of a large number of recessive genes, which affects the life span of dogs.
Wolves and dogs
The survival of the fittest in wolves makes them live longer. Although the living conditions are bad, evolution does not care about life and death. Whether it is the death of young cubs or the death of adult wolves, as long as it is not a mass death, it will not be greatly affected. By shrinking the gene pool, wolves can still pass on excellent genes.
The environment only restricts the number. The number of dogs is far greater than the number of wolves. This is due to being close to people, "Humans get the Dao, chickens and dogs ascend to heaven." The habitat of wolves is reduced, food is scarce, so survival is not guaranteed, and the number is greatly reduced. In fact, although the theory of evolution depends on the environment, it does not care about the life and death of species. If you look carefully, the key to the theory of evolution is the time point of life and death, as long as the reproduction is completed. The task, even if the males die on the day of mating, the population can be guaranteed. For example, the female praying mantis will eat the male praying mantis afterwards, and the marsupial shrew can continue for 14 hours until they die. There is also a black widow. Although the male died early, the population Still no decline.
The death of a dog is actually very common, but now that human technology is more advanced, it can avoid the passing of life to a certain extent, but it cannot be solved. The dog does not have enough exercise and the gene has been distorted, so the dog The life span of the children is lower than their ancestor wolf.
