The biological basis of religious chastity

Tuesday, 5 June 2012

by Achim Eberhart

Cosmos Online

BRISBANE: Strict religious rules about female sexuality achieve low levels of cuckoldry and demonstrate the role of religion to reduce extramarital sex, according to American anthropologists.

This research sheds light on the purpose and origin of religious ideologies regulating sexuality. “One function of sexual morality in religion is to help males to assure their paternity,” said Beverly Strassmann of the University of Michigan in the U.S. and lead author of the study published today in the American journal Proceedings of the National Academy of Sciences.

A woman always knows that she is the mother of her children – a man can never be entirely sure who the father is. For this reason, male animals deploy a number of tactics to ensure their paternity.

Male tactics to ensure paternity

Be it a damselfly clinging on to the female after copulation to prevent rivals access to her or a vaginal plug deposited by male guinea pigs during intercourse to block sperm from a possible second mating.

“In humans, religion uses ideology to forward the same reproductive agenda of preventing cuckoldry,” said Strassmann.

The major world religions developed in patriarchal societies, in which wealth was inherited along the paternal line. Consequently, being the true father of ‘your’ son was important and the religious doctrines pose strict limits on sexuality and stipulate harsh penalties for adultery. Typically, the religious texts place more weight on female than male chastity.

Studying the Dogon people of Mali

This study now shows that stronger rules about female sexuality and closer monitoring of women by men effectively limits cuckoldry in a traditional African community.

To test the efficiency of religious decrees to avoid extramarital offspring, Strassmann and her colleagues studied the indigenous Dogon people of Mali in West Africa.

The Dogon live a traditional farming lifestyle and modern innovations such as electricity or contraception are not available to them. In the male-dominated Dogon communities, the indigenous religion coexists with Islam and a Christian minority – often within the same families. Polygyny is common in all of these religious groups.

While all these religions share similar tenets about faithfulness, the indigenous religion requires women to retreat at night to separate ‘menstrual huts’ and Muslim women in the Dogon communities need to inform their husbands when they are menstruating and are not allowed to pray.

To test whether men were the biological fathers of their sons, the researchers analysed Y-chromosomal DNA of male members of the communities. Then they compared the number of father-son mismatches between the different religious groups.

They generally found only few cases of ‘nonpaternity’ but five times more in Christian families compared to those practising the indigenous religion. The Muslims scored slightly but not significantly higher than the Dogon. Social factors such as wealth or the number of wives the father had did not influence these results.

These data show that the strict control mechanisms over women, prescribed by the indigenous religion and Islam, which are missing in Christianity, are efficient tools to ensure husbands’ paternity of their children.

Forcing women to disclose their menses allows the husbands’ families to closely monitor women and their reproductive status – especially the resumption of ovulation after breastfeeding.

Resumption of menstruation linked to fertility

“In a population that doesn’t practice contraception, the resumption of menstruation after giving birth is closely tied to the resumption of fertility,” said Strassmann.

“When a woman visits the menstrual hut, her husband and his family know that she will soon conceive a child.” This is a signal to them to watch her very closely.

Their study helps to explain the origin of religious patriarchy, the double-standard and religious rules that penalise women, said Strassmann. “The men are running the religion. And they are not running the religion just for some pure moral purpose. They’re running the religion for a biological purpose, which relates directly to reproduction.

Is there another interpretation?

“I think that that’s a really fascinating study,” said Darren Sherkat, a sociologist at the Southern Illinois University in the U.S. “And I think that the value of it in terms of the description of the differences across those groups is very valuable for science.”

But he differs in his interpretation of the observations. Sherkat argues that the anthropologists may have found a “simple social control effect” that has to do with the size of the different groups.

“The strong biological/evolutionary theoretical angle of the paper is bent in the wrong direction.”