BIG ENCYCLOPEDIA FOR CHILDREN AND ADULTS
Where did dogs come from? Detailed answer Directory / Big encyclopedia. Questions for quiz and self-education Did you know? Where did dogs come from? All members of the dog family are descended from a wolf-like creature. This ancient dog, called the "father of dogs", roamed the forests 15 years ago. The habits and habits of wild dogs have been inherited by domestic dogs. Domestic dogs are relatives of wolves, coyotes, and jackals. They are all typical wild dogs and belong to the canine family. They are so close to each other that dogs can mate with wolves, coyotes, jackals and produce offspring. But they cannot be related by blood to foxes. Foxes belong to another species of the canine family. Once upon a time, a man tamed several domestic dogs. Maybe these dogs were wolf cubs. They could also be cubs of jackals and any other animals of the wild dog family. Man has discovered that these animals can be useful. He began using them to hunt other animals and birds. Becoming more civilized, a person realized that a dog can also be a friend and helper in protecting homes and livestock. Over time, different breeds of dogs have been bred and used for different purposes. Dogs with long noses, such as setters, pointers, hounds, are used to sniff out traces of game, birds, hares. Others, such as greyhounds, chase hares and deer. Strong, heavy dogs, one of which is a mastiff, pull carts. Special dogs were bred for guard service and enemy detection during the war. Along with hunting and working dogs, there are dogs for sports and for fun. Author: Likum A. Random interesting fact from the Great Encyclopedia: What are gems? Precious stones have always amazed people. For thousands of years, people wore them as amulets to protect themselves from disease and evil spirits. It was believed that with the help of some gems, their owner was able to predict the future. Other stones allegedly made it possible to determine whether the suspect was guilty or not. In ancient times, precious stones differed only in color. Rubies are all red stones. All green stones were called emeralds, and blue stones were called sapphires. Later it became clear that some stones are stronger and more durable than others. It also became clear that the cost of precious stones depends not only on color, brilliance, uniqueness, but also on their strength. For example, today diamonds are considered the most expensive stones because, in addition to their beauty, they have the highest durability compared to other precious stones. All gems are called precious stones. But, strictly speaking, only the four most expensive stones can be classified as precious: diamond, ruby, emerald and sapphire. Others belong to semi-precious stones, these are opal, amethyst, topaz. Many of the precious and semi-precious stones are closely related. Diamond, the most expensive of gems, is also the simplest in structure: it consists of one chemical element - pure carbon. Rubies and sapphires are classified as corundum. Rubies have a carmine color due to the presence of a small amount of iron in corundum. And the presence of various oxides gives sapphires different shades of blue and blue. Most gems include various combinations of "silicates". Topaz and tourmaline belong to the silicate family, as do garnets and jadeites. Some less expensive gems belong to the quartz group, which is made up of pure silica. They include amethyst. Opal is silica containing 5-10% water. By the way, it is believed that opal is one of the few precious stones that bring misfortune to their owners. Currently, the first attempts are being made to create artificial gems. Among them are diamonds, emeralds, rubies and sapphires. This is not a fake, in fact, these are stones similar to natural ones, only they are created in laboratories!
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