As a new father, this story from the New York Times grabbed my attention. It reports on a study that showed testosterone levels decrease in men when they become fathers. The more fatherly activity a man participates in, the more his testosterone drops.

Why the drop? The study suggests it helps men be more committed in their relationships and support their partners in child rearing. In other words, the study suggests that on a biological level, men are supposed to be engaged in raising children.

“The real take-home message,” said Peter Ellison, a professor of human evolutionary biology at Harvard who was not involved in the study, is that “male parental care is important. It’s important enough that it’s actually shaped the physiology of men.”

To many, testosterone equals manliness, but several researchers in the article make a point of saying men shouldn’t worry that children and the drop in testosterone that goes with them, will kill their manhood.

The lowering of their testosterone did not prevent the men in the study from having more children. “You don’t need a lot of testosterone to have libido,” [said the study's co-author Dr. Christopher Kuzawa].

“If guys are worried about basically, ‘Am I going to remain a guy?’” [Emory University anthropologist Carol] Worthman [who was not involved in the study] said, “we’re not talking about changes that are going to take testosterone outside the range of having hairy chests, deep voices and big muscles and sperm counts. These are more subtle effects.”

Dr. Ellison explains why he thinks some men may be afraid of this study.

“Unfortunately,” Dr. Ellison added, “I think American males have been brainwashed” to believe lower testosterone means that “maybe you’re a wimp, that it’s because you’re not really a man.

“My hope would be that this kind of research has an impact on the American male. It would make them realize that we’re meant to be active fathers and participate in the care of our offspring.”

Perhaps this will reassure some men that it’s manly – in the biological sense – to be a full partner in raising children.

Read the full article here.

H/t: Art of Manliness.

Photo credit: bobhouser/Flickr

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