Laterality

The handedness is the preference of most human beings on one side of his body. The most popular is the left-handedness. It can also be applied to animals and plants.

Human handedness

Most humans are right-handed. Most also show a predominance of right side. That is, if forced to choose prefer the eye, or foot or the right ear. The cause (or causes) of laterality are not understood, but it is thought that the left brain controls the opposite side of the body and the left hemisphere to be the predominant. This is true for 90-92% of humans because the left brain is responsible for the language.

In all human communities are mostly right-handed individuals. This trend may have a biological origin as well as be the result of cultural reinforcement. The predominance of right or cultural content can be seen after a brief analysis of the language. In Castilian word "sinister" (Latin sinistra, left) in addition to meaning "left hand", is also used derogatory and negative meanings (it describes what is perverse, malicious or unhappy, or harm anyone could be compensated by an insurance company). In French the word gauche means too awkward or intrusive. In English the word left (left) comes from the Anglo Lyft, which means useless or weak. There must also say that the word comes from ancient Greek aristocracy Aristera (left). This bias toward anything derogatory left is not confined to European culture characters of Chinese writing are designed for righties, and has not found any human community in which there is a predominance of the left side.
Forced Laterality
When a person is forced to use the opposite hand to that used naturally spoken forced laterality (in the case of unskilled, "disgruntled lefties). A study by the Department of Neurology at the University of Klee (North Staffordshire Royal Infirmary) indicates that the forced lateral explain the low percentage of lefties in the older population at the time of that investigation.

The most skillful counter-clockwise circles drawn (or counterclockwise), and no right-handed (or clockwise) which would support the thesis of the dominance of the left hemisphere of the brain.