Testosterone of young husbands rises with children in the home

Evolutionary theory suggests that a man's testosterone (T) decreases after his fathering of children, when his priority shifts from mating to cooperative parenting (Fatherhood: Evolution and Human Parental Behavior, 2010). A variation in this theory has T decreasing for highly educated fathers but increasing for less educated fathers (Evol Hum Behav, 33, 2012, 665). The Vietnam Experience Study of 4462 male army veterans is here used to explore related hypotheses: (i) that T decreases with the presence (or increasing number) of children in the man's home and (ii) that the T rises or falls depending on father's education. These related hypotheses are not supported. To the contrary, among young fathers, ages 30-35 years, T is higher with the presence and number of children in the home, independent of education.