Many scientists are concerned about the question: “Has human evolution stopped”? Most of them believe that the answer should be yes. Indeed, if we consider this process as natural selection, then how can a person who has completely conquered nature and able to feed himself and children evolve? And given the modern achievements of medicine, any doubts disappear - he has reached his perfection.
But this position has its weaknesses. Invisibility does not mean absence. Modern human evolution is a slow process, so it is very difficult to track in real time. Moreover, the assumption of real estate development leads to a conclusion that contradicts the results of a study of the human genome.
The simplest meaning of the word “evolution” is that it is a process of changing the frequencies of alleles in a population over time. Most of these changes consist in the replacement of some alleles by others under the influence of natural selection. To determine how a person’s evolution is moving, it’s enough to find any signs of allele frequency changes in the genome.
Recent studies have identified several of the most striking examples of the evolution of modern man.
The first is the so-called high-altitude disease. The peoples who settled in the highlands of the planet are faced with insufficient oxygen in the air. Such starvation leads to fatigue, dizziness and insomnia. In especially severe cases, the consequences are irreversible - pulmonary edema and subsequent severe death. Moreover, acclimatization allows you to get rid of only part of the symptoms.
In the course of research, it was found that the indigenous people of Tibet adapted to the conditions created in the form of a lack of oxygen. It was found that in most Tibetans, blood is 10% more oxygenated than 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 lactose intolerance. It is a carbohydrate that is found only in mammalian milk. It is absorbed in the human body with the help of a special enzyme - lactase, which is intensively produced in the first year of life, after which the synthesis of this substance goes into decline. In most adults, lactase is not synthesized, so lactose is practically not absorbed.
Surprisingly, American Indians, Australian Aborigines, and Southeast Asians and South Africans suffer from drinking whole milk. It causes bloating, diarrhea, colic, vomiting, and nausea. At the same time, they can consume fermented milk products, since the fermentation process breaks down lactose.
The ability to assimilate lactose at a more mature age, man acquired on two different continents - Europe and northern Africa. Moreover, they arose independently of each other and appear in different parts of the genome. Such a double mutation has become a reliable sign that human evolution is continuing.
Special attention should be paid to the problem of AIDS. The pandemic of this disease, which began in the 80s, has become one of the main demographic factors at the moment. Almost 40 million people suffer from this disease, with the peak of the epidemic occurring in the South African region, where about 25% of adults are infected.
Many stages of human evolution have been 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, certain compounds are formed in the human body that can effectively fight this incurable disease.
The origin and evolution of man took more than one thousand years. During this time, our brain volume increased, facial features changed , we began to walk straight, learned to talk. Day by day, we develop, acquire new skills and abilities, effectively fight diseases and try to survive in a complex world, therefore we cannot say that evolution has stopped, it just slowed down a little.