This is the kind of news coverage about a study that results in science and journalism about science losing credibility. To get warmed up, check some of the headlines:
Or see countless other silly headlines in a simple web search that will come up with probably more than 100 news stories.
It’s all based on a study published in the Proceedings of the National Academy of Sciences, “Testicular volume is inversely correlated with nurturing-related brain activity in human fathers.”
It doesn’t appear that Emory University, home of the authors, distorted the findings. This Emory story states:
“Men with smaller testes than others are more likely to be involved in hands-on care of their toddlers, finds a new study by anthropologists at Emory University. …
Smaller testicular volumes also correlate with more nurturing-related brain activity in fathers as they are looking at photos of their own children, the study shows.
Our data suggest that the biology of human males reflects a trade-off between investments in mating and parenting effort, says Emory anthropologist James Rilling, whose lab conducted the research.
The goal of the research is to determine why some fathers invest more energy in parenting than others. Its an important question, Rilling says, because previous studies have shown that children with more involved fathers have better social, psychological and educational outcomes. …
The study included 70 biological fathers who had a child between the ages of 1 and 2, and who were living with the child and its biological mother.
The mothers and fathers were interviewed separately about the fathers involvement in hands-on childcare, including tasks such as changing diapers, feeding and bathing a child, staying home to care for a sick child or taking the child to doctor visits.
The mens testosterone levels were measured, and they underwent functional magnetic resonance imaging (fMRI) to measure brain activity as they viewed photos of their own child with happy, sad and neutral expressions, and similar photos of an unknown child and an unknown adult. Then, structural MRI was used to measure testicular volume.
The findings showed that both testosterone levels and testes size were inversely correlated with the amount of direct paternal caregiving reported by the parents in the study.”
The Emory blog post listed some of the study’s limitations:
“Although statistically significant, the correlation between testes size and caregiving was not perfect.
A key question raised by the study findings is the direction of casualty (sic: I’m sure they meant causality). Were assuming that testes size drives how involved the fathers are, Rilling says, but it could also be that when men become more involved as caregivers, their testes shrink. Environmental influences can change biology. We know, for instance, that testosterone levels go down when men become involved fathers.
Another important question is whether childhood environment can affect testes size. Some research has shown that boys who experience childhood stress shift their life strategies, Rilling says. Or perhaps fatherless boys react to the absence of their father by adopting a strategy emphasizing mating effort at the expense of parenting effort.
While it could have been stated more clearly, that excerpt nails the huge leap from the assumptions of the study to any proof of cause-and-effect. It discussed correlation – not cause. In other words, it’s nuts to have news headlines like the ones I listed above.
There are countless ways to poke holes in the fMRI analysis of 70 men, but I’ll leave that to the experts.
The clamor for cutesy cleverness outpaced real scrutiny in most of the stories we’ve seen.
CNN.com quoted one of the study authors succinctly: “Rilling says the study is not about “good” or “bad” dads.”
So again, where did all of those headlines come from?
And didn’t we have a possibly pending war, the unfolding Affordable Care Act, even another Anthony Weiner story to cover today instead of all the attention given this?
ADDENDUM: This is even more nuts. Each day I work really hard but may reach only relatively small numbers of people with articles that I think are important to try to improve the public dialogue about health care. Today my traffic is through the roof, and it’s all because I had testicles or nuts in my headline. And that, at least temporarily, put me in a prominent position on Google Search. Nuts.
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