In marriage, there is much more going on than meets the eye. According to the report, men who have never married or are divorced have higher levels of testosterone than do married men, particularly married fathers. Since testosterone is associated with risk-taking and anti-social behavior, this makes the married man more civilized and dependable.
If marriage influences the biology of the father, he, in turn, influences the biology of his daughters. Girls in intact married households experience puberty later than girls in single-parent households. This is important, Wilcox notes, "because when girls develop prematurely, they are more likely to become attracted to older boys and men and to have sex and become pregnant at an early age."
If a girl lives with an unrelated male (say, a stepfather or a mother's boyfriend), she hits puberty even earlier than a girl living with only her mother. The speculation is that the father emits pheromones — biological chemicals communicating sexual signals — that delay puberty in his daughter, while an unrelated male emits pheromones that accelerate it. If so, there is nothing to be done about this phenomenon, since no one consciously controls his pheromones.
Perhaps dad would be dispensable if government could somehow cushion children against his absence? It can't. Sweden has an all-enveloping welfare state and system of socialized medicine, but even there the report says, "Boys reared in single-parent homes were more than 50 percent more likely to die from a range of causes — such as suicide, accidents or addiction — than were boys reared in two-parent homes." There's just no substitute for dad.