English rivers waters – Substances blocking fertility

English rivers waters - Substances blocking fertility

English rivers waters – Substances blocking fertility

English rivers waters – Substances blocking fertility – British scientists claim that in the waters of
the English
rivers is a group of substances blocking the male sex hormone testosterone.
Thus reducing
fertility in men. After examining fished out of the rivers fishes.
I
t turned out that these compounds stimulate the development of female characteristics in males.

Left-handedness two types

Left-handedness two types - Defense.gov photo essay

Left-handedness two types

Left-handedness two types – Today we distinguish between left-handedness:

  • genetic, occurring in patients whose left-handedness is genetically programmed,

According to an earlier theory neuropsychologist Norman Geschwind (1926-1984) the probability of left-handedness is more, if the fetus was exposed to increased concentrations of the male hormone testosterone, which affects the development of the cerebral hemispheres. This theory may explain why in the euro-american society among left-handers are more men (12%) than women (8%).

  • pathological, the cause is the dominance of one cerebral hemisphere,

According to another theory, left-handedness is caused by problems during labor, as a result of oxygen deprivation causes damage to the brain. According to statistics among left-handers who have had complications during childbirth, 30% are mentally retarded.