According to a HealthDay report, researchers are hoping to discover if the difference between fathers who are highly involved with child rearing and fathers who aren't is a matter of brain function or anatomy.
More specifically, they've been exploring a link between the size of a man's testicles and the level of testosterone, and parenting style.
The study, which included 70 fathers of children aged 1 to 2, used blood tests to measure testosterone, and interviews with fathers and mothers separately asking how often the man fed, bathed, prepared food for children or took them to appointments. Researchers also used an MRI brain scan to monitor the fathers' brain activity while looking at pictures of children. MRI technology was also used to measure the size of the men's testicles.
What they found suggested that the men with lower testosterone and smaller testes were more engaged caregivers. Testes volume was also correlated with the the men's increased neural response, specifically in the reward center of the brain, to viewing photos of their own offspring.
These results don't take into account that the very act of being involved caregivers may have an effect on testosterone levels and testicle size.
Read on for more about the correlation between size and fatherhood.
I have always been curious about how parenting, a person's response to being a parent, correlates to biology vs. environment. When I compare myself to some mothers who I deem better suited — far more natural, relaxed, and open — to motherhood and all it entails, I find myself using the expression "cut from a different cloth" a lot.
But if scientists started making connections between, say, breast size and mothering aptitude, I'm not sure I would want to hear about it. Yet we can't deny that humans are animals driven to perpetuate the species, and it only follows that biology and anatomy might affect our success, or failure, at this:
The Guardian's report on this study boils the study down to simple facts about animal behavior:
"The findings are the strongest evidence yet that variations in male anatomy reflect competing evolutionary strategies that can be distilled down to mating as much as possible versus investing more in parenting. Both are effective ways to maximize an animal's chances of having offspring that continue their lineage."
I can easily imagine how my husband, a Brit who just so happens to be a remarkably engaged father, would react to this study. "Sounds like a load of bollocks!" he would say. And he would be right. See definition of bollocks here.