Nurture Assumption Debunked Again
Girls who grow up without their fathers at home reach sexual maturity earlier than girls whose fathers live with them (and early-bloomers are more likely to suffer depression, hate their bodies, engage in risky sex and get pregnant in their teen years).
Research by Jane Mendle (”Associations Between Father Absence and Age of First Sexual Intercourse“) suggests heredity is the cause: the genes that make a dad more likely to leave his family also cause early sexual development.
The researchers analyzed data American National Longitudinal Survey of Youth data on 1,400 boys and girls, each of whom was related to at least one other subject through their mother. Most of the mothers were pairs of sisters, but some were identical twins or first cousins raised as sisters.
The more closely related the cousins were — by having mothers who were identical twins, for instance, versus cousins — the closer their age at first sexual experience, regardless of whether or not a father lived in the home.