A new study out of Emory University in Atlanta, Georgia has found a relationship between the size of a man’s testicles and engagement as a father.
James Rilling and his team at Emory, used MRI scans to measure the volume of the testicles of 55 fathers. The team asked these father volunteers (and the mothers of their children) a series of questions to determine how involved they are as fathers. The team also used fMRI brain scanners to look at the brain activity of the men as they viewed photos of their children.
Men with smaller testicles got the best parenting scores in the questionnaires. When looking at pictures of their children, these men also showed more activity in regions of the brain associated with empathy and motivation to care for offspring than men with bigger testes, suggesting they’re more nurturing fathers.
Rilling does not understand completely why smaller testicles might make men better fathers. he says, “We’re assuming that testis size drives how involved the fathers are, but it could be that when men become more involved as caregivers, their testes shrink.”
Don’t worry all you guys out there with hefty cojones, Rilling insists that the findings do not automatically indicate that men with bigger testicles will be worse fathers.
“Most fathers choose how involved they are in their child’s upbringing,” says Rilling. “It might be more challenging for some men to do these kinds of caregiving activities, but that by no means excuses them,” he says.