Human Anatomy - Kotsan I. Y. 2009

The Place of Man in Nature

Human beings, like any other living Organism belonging to the animal kingdom, share all the fundamental traits characteristic of living creatures. The essential properties of a living organism include: 1) growth

and development; 2) reproduction; 3) Variability and heredity, which enable the organism to adapt to its surrounding environment; 4) active spatial locomotion; 5) a continuous metabolic exchange with the external environment. Each of these properties has a specific structural foundation, which, in turn, depends on the level of Organization OF THE living organism and the environment in which it exists.

From a biological standpoint, humans belong to the phylum Chordata, subphylum Vertebrata, Class Mammalia, Order Primates, and family Hominidae.

Modern humans (homo sapiens) fully emerged approximately 30,000 to 40,000 years ago. Compared to the overall evolution of life on Earth, which spans roughly 3 to 3.5 billion years, this is a very brief period. Nevertheless, humans have taken a giant leap in their development. This is due to humanity's unique position in nature. Among all animals living on Earth, humans alone are social beings. We live in society and, consequently, owe many of our traits to our social nature. Unlike all other animals, humans do not live merely in a natural environment, but in an artificial one that they create and constantly modify.

Human Evolution occurred not only through changes in physical body Structure and behavior, but also through The Development of culture—that is, the creation of a shared body of knowledge that is utilized collectively and expands from generation to generation.

The process of accumulating knowledge dates back to the earliest stages of human culture. Initially, knowledge was passed down through generations in the form of craft skills for making tools, basic clothing, dwellings, and the like; later, through drawings, and subsequently through writing. All of this became possible thanks to the evolution of a specialized organ of labor—the hand, which humans progressively refined through labor activity—and a means of communication, namely articulate speech.

Thus, humanity's unique position in nature is linked less to the Biological features of its physical structure than to its social essence and participation in labor. Labor activity is one of the key factors determining human physical and spiritual development.

The physical Development of the organism was also significantly influenced by such factors as Nutrition, ecology, housing and living conditions, and social status, which exerts a profound and multifaceted impact.

The advancement of human labor, along with the improvement of technology and technical equipment, stimulated the development of human society and transformed its social structure, while these changing social conditions in turn reflected upon human biological properties.

Having passed through a series of evolutionary stages—Pithecanthropus, Sinanthropus, Heidelberg man, Neanderthal, Cro-Magnon, and modern humans—the human organism attained the higher level of organization characteristic of people today.

The most distinctive features that differentiate The Human Body from other mammals, including apes, are:

1) a highly developed Brain (consequently, the braincase in humans dominates over the facial Skeleton, a trait unique to the human organism);

2) an upright posture, which freed the hands from the function of locomotion and transformed them into Organs of labor;

3) the anatomical arrangement of Internal Organs, which corresponds to an upright posture and rests upon a broad pelvis;

4) upper limbs that are spread out at the shoulders (resulting in a chest width that exceeds its depth);

5) the development of an opposable human thumb, enabling the grasping and holding of tools and objects of labor;

6) the differentiation of upper limb Muscles (particularly those of the forearm and hand), which allows for precise and varied movements (for instance, playing the violin is exclusive to humans);

7) A large number of movable joints of diverse shapes;

8) a spine featuring 4 characteristic curves, with the Skull perched atop it rather than «suspended» from the front, as seen in quadrupedal animals with horizontal body postures;

9) Skin that has almost entirely lost its Hair covering;

10) a Larynx that, together with the Organs of the Oral Cavity, has evolved into an organ of speech;

11) legs that are longer and stronger than the arms, featuring an arched FOOT (a trait unique to the human organism).