The use of the thumb, the body lateralization (ie to be right-handed or left-handed), communicate through speech, many mental functions such as the ability to reason, to identify, to invent, to imagine they are all characterizations of the human animal than . However the list is missing one other important difference is that the “standing”. This has been the mainspring of human evolution because the ability to stand, and so to walk, has made possible the development of the functions described above over millions of years.

Well, that decisively favors the upright is the spine, or backbone, consists of 33 bones (vertebrae) that are articulated on each other: from top to bottom are the 7 cervical vertebrae, the thoracic 12 ( or dorsal), the 5 lumbar, 5 sacral and 4 coccygeal the. While the last 9 in adults are usually fused together, the other 24 are mobile and “written off” with each other through special training cartilage called intervertebral discs. Around the vertebrae are robust with strong ligaments and large muscles often forming a large surface, from the neck to the sacrum, is called “back.” Also important are the so-called “corners” of the spine, ie cervical lordosis, dorsal kyphosis, lumbar lordosis, sacral kyphosis, visible with an x-ray of the entire column (by right or left side) and a clinical examination particularly attentive to the positions it takes when a person is stopped while walking or standing. These four alternate corners are mainly responsible for elasticity and strength of the column, in fact, recent studies of engineering applied to the understanding of the human body have shown that if the spine is presented in a straight line would be seventeen times less strong than normal and mobile Finally all the vertebrae have their own forum, called the intervertebral spinal cord where it passes, the set of nerves that connect all parts of the body to the brain thus allowing it to receive and to give them resulting in “answers”.