Hirsutism body hair, particularly in locations where women normally do not develop terminal hair during puberty (chest, abdomen, back, and face). The medical term for excessive hair growth that affects any gender is hypertrichosis. Hirsutism can be caused by either an increased level of androgens, the male hormones, or an oversensitivity of hair follicles to androgens. Male hormones such as testosterone stimulate hair growth, increase size and intensify the growth and pigmentation of hair. Other symptoms associated with a high level of male hormones include acne, deepening of the voice, and increased muscle mass. The condition is called hyperandrogenism. Growing evidence
Reciprocal altruism in humans Reciprocal altruism in humans Reciprocal altruism in humans refers to an individual behavior that gives benefit conditionally upon receiving a returned benefit, which draws on the economic concept – ″gains in trade″. Human reciprocal altruism would include the following behaviors (but is not limited to): helping patients, the wounded, and the others when they are in crisis; sharing food, implement, knowledge. The concept of ″altruism″ was firstly coined by the French philosopher Auguete Comte in the 19th century, which was derived from the French word ″"altruisme"″. Comte believed that ″altruism″ is a moral doctrine, which is the opposite of egoism,