Evolutionary doctrine is the theoretical basis of biology. It studies the causes and mechanisms of the historical development of all living organisms. Human evolution has its own characteristics and factors.
What is anthropology
According to evolutionary doctrine, man as a biological species was formed over a long period of time. The processes of its historical development are studied by anthropology science.
The emergence of man has its own characteristic features. They consist in the fact that both social and biological factors of evolution influence the formation process . The first group includes the ability to work, speech, abstract thinking. The biological factor of human evolution is, in particular, the struggle for existence. As well as natural selection and hereditary variation.
The main provisions of evolutionary theory
According to the theory of Charles Darwin, environmental conditions can cause changes in the structure of living organisms. If they are not inherited, then their role in the evolutionary process is insignificant. In some individuals, changes occur in germ cells. In this case, the sign is inherited. If it is useful under certain conditions, then organisms are more likely to survive. They successfully adapt and produce prolific offspring.
Struggle for existence
The main biological factor in human evolution is the struggle for existence. Its essence lies in the emergence of competition between organisms. The reason for its appearance is the mismatch between the ability of different species to eat and reproduce. As a result, a species survives that is able to best adapt to specific conditions.
Despite the fact that the process of the emergence of modern man was subject to general laws, there are a number of differences. Natural selection took place not only in terms of strength, dexterity, and endurance. In addition to these physical signs, the level of mental development also played a special role. Individuals who learned to make the most primitive tools and use them, communicate with fellow tribes, and act together had a greater chance of survival.
Natural selection
In the course of the struggle for existence, natural selection takes place - a biological process in which adapted individuals survive and actively reproduce. Those who could not adapt die.
Thus, natural selection is also a biological factor in human evolution. Its feature was that individuals with pronounced social traits survived. The most viable people were those who invented new tools, acquired new skills and socialized. Over time, the value of natural selection in the process of anthropogenesis decreased. This is due to the fact that ancient people gradually learned to build, ennoble and heat homes, make clothes, grow plants, tame animals. As a result of this, the value of natural selection gradually decreased.
Hereditary Volatility
The biological factor of human evolution is hereditary variability. This property of living organisms lies in the ability to acquire new traits in the process of its development and transmit them by inheritance. Naturally, only useful traits had evolutionary significance in the process of anthropogenesis.
A human being is brought closer to mammalian animals by a number of similar biological features. This is the presence of mammary and sweat glands, hair, live birth. The body cavity is divided by the muscular septum by the diaphragm into the chest and abdominal parts. Similar signs are the absence of nuclei in red blood cells of red blood cells, the presence of alveoli in the lungs, the general plan of the structure of the skeleton, differentiated teeth. Both in humans and animals there are rudimentary (underdeveloped) organs. These include the appendix, the third eyelid, the rudiments of the second row of teeth and others. Scientists know cases of the birth of people with the characteristic features of animals - a developed tail, a continuous hairline, an additional number of nipples. This is additional evidence of the origin of man from animals. But in the process of anthropogenesis only the most useful signs have been preserved.
Specific only to humans are such biological traits:
- upright posture;
- an increase in the brain and a decrease in the facial section of the skull;
- vaulted foot with a highly developed thumb;
- movable hand, contrasting the thumb with the rest;
- an increase in the volume of the brain, the development of its cortex.
Human biological evolution is closely related to social. For example, the ability to make fire and cook led to a decrease in tooth size and intestinal length.
Biological factors of human evolution are a prerequisite for the formation of social, which in the aggregate led to the appearance of intelligent humans on Earth.