Many scientists are concerned about the question: "Has the evolution of man stopped"? Most of them believe that the answer should be positive. Indeed, if we regard this process as a natural selection, then can a man who completely conquered nature and is able to feed himself and children evolve? And given the modern achievements of medicine, any doubts fall away - he reached his perfection.
But this position has its weak points. Invisibility does not mean absence. The modern evolution of man is a rather slow process, so it is very difficult to track it in real time. Moreover, the assumption of real estate development leads to a conclusion that contradicts the results of the study of the human genome.
The simplest meaning of the word "evolution" is thatthis is the process of changing allele frequencies in a population over time. Most of this kind of change is the substitution of some alleles by others under the influence of natural selection. To determine how the evolution of a person is moving, it is enough to find any signs of changes in the frequencies of alleles in the genome.
Recent research has made it possible to identify some of the most vivid examples of the evolution of modern man.
The first is a so-called altitude sickness. Peoples who settled in the high-altitude areas of the planet, faced with a lack of oxygen in the air. This starvation leads to fatigue, dizziness and insomnia. In particularly severe cases, the consequences are irreversible - pulmonary edema and subsequent severe death. And acclimatization allows you to get rid of only a part of the symptoms.
In the course of the research, it was found that indigenousThe inhabitants of Tibet adapted to the existing conditions in the form of a lack of oxygen. It was found that most of the Tibetans have blood 10% oxygenated, compared to ordinary people. This feature is inherited, so you can safely put forward the assumption that it depends on one gene.
The second striking example is intolerancelactose. It is a carbohydrate, which is found only in the milk of mammals. It is absorbed in the human body with the help of a special enzyme called lactase, which is intensively produced in the first year of life, after which the synthesis of this substance goes to a decline. For the majority of adults, lactase is not synthesized, so lactose is practically not digested.
Surprisingly, the American Indians,Australian Aborigines, inhabitants of Southeast Asia and southern Africa suffer from the use of whole milk. It causes bloating, diarrhea, colic, vomiting and nausea. In this case, they can consume sour-milk products, since the fermentation process breaks down the lactose.
The ability to absorb lactose in a more matureaged man acquired on two different continents - Europe and northern Africa. At the same time they appeared independently of each other and manifested in different parts of the genome. This double mutation has become a reliable sign that human evolution continues.
Special attention should be paid to the problem of AIDS. The pandemic of this disease, which began in the 1980s, has become one of the main demographic factors at the moment. Almost 40 million people suffer from this disease, with the epidemic peak in the South African region, where about 25% of adults are infected.
Many stages of human evolution were passed -but the key one is natural selection. It was he who became one of the factors in the emergence of AIDS, as it implies certain mutational processes that provide protection against the disease. And, most likely, over time, in the human body, certain compounds are formed that can effectively fight this incurable disease.
The origin and evolution of man occupied more than onea thousand years. During this time, we have increased brain volume, facial features have changed, we began to walk straight, learned to talk. Day after day, we develop, acquire new skills and abilities, effectively fight diseases and try to survive in a complex world, so we can not say that evolution stopped, it just slowed its course a little.
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