Seminar Two
Evolution of sexuality
Menstrual taboos

Why do many cultures consider menstruating women as taboo, often confining them to menstrual huts? An article by the anthropologist Meredith Small points out that menstrual taboos are effective in providing men with honest signals of female reproductive status.

A woman in a menstrual hut, or otherwise isolated because of her menstrual bleeding, is recognized as a fertile woman who is not already pregnant and would soon be ready to conceive. Such information would be useful to men in their paternity assessment, both past and future. A man could be sure that such a woman is of age to become pregnant, is not already pregnant, and is healthy enough to become pregnant.

Another anthropologist, Beverly Strassmann, lived for over two years with the Dogon culture of Mali, West Africa, where menstruating women were sent to menstrual huts outside the walled compound of the village. She showed, from urine samples, that the women never went to the huts during pregnancy or amenorrhea (absence of menstruation). She concluded that the menstrual taboos of this traditional culture were effective in providing men with honest signals of female reproductive status.

Not all traditional cultures have considered menstrual blood dangerous or polluting, however. Men in the Gimi culture of Papua New Guinea fear menstrual blood but enjoy the risks of exposure to it. Their songs celebrate the eroticism of intimacy with a menstruating woman.

There are clearly variations on this theme across human cultures. Human behavior is flexible, shaped by culture and upbringing as well as by genes.