19 September 2011

TESTOSTERONE & CULTURE: A Comment on Another Adaptationist Fable

The headline on September 12 read: “Fatherhood Cuts Testosterone, Study Finds, for Good of the Family.”  The article – on the front page of the NY Times – told of a recent study that found that becoming a father and engaging in childcare decreases a man’s testosterone levels.

For the scientists who produced the study, and for the newspaper’s science reporter alike, there is but a single, inevitable (and thus extra-cultural) consequence of this reported drop in testosterone levels: it makes men, on their view, less likely to seek multiple sex partners and more likely to be monogamous.  The decrease in testosterone is thus “adaptive” to parenting, by virtue of it leading a man to be more anchored to a child’s mother—with the presumption (in the study and news report alike) being that the child in question is indeed the father’s genetic child (as well as the mother’s).

What these scientists and the NY Times's science journalist are entirely blind to is the possibility that there is no singular or automatic behavioral consequence of a drop in a man's testosterone level and, indeed, that a man’s response may depend a great deal on socialization and cultural values.  Consider the possibility that some men in some contexts, if they experience a drop in “libido” (which is the presumed result of a drop in “testosterone,” in the study and NY Times alike), might seek to recapture or rekindle their “libido” by seeking out a new partner.  In that case, if fatherhood indeed produces a drop in testosterone, the drop might lead to more sexual “infidelity,” rather than more “faithfulness”!

And what about the possibility that higher levels of testosterone are what make some men, at least in some social contexts, more monogamous—if sticking with an established partner provides a more reliable sex life than seeking out a new partner?  Surely, it cannot be the universal experience, or essential character, of all men to be able to find a new sex partner, whenever they so desire--"at will," as it were.  This is, though, precisely the presumption (the male fantasty, one might say) in a great many of the adaptationist fables told by evolutionary psychologists.

The larger question is this: how, given the range of human variability across time and space, can a group of scientists and science journalists be so stubbornly simple-minded (and so simple-mindedly stubborn) as to believe in a singular, determined, and universal behavioral outcome as a result of a drop in the level of a given hormone?  And when will these scientists, and science journalists, finally get the more complex truth that there is always a complex interaction between human biology and culture?


  1. Right on. I waded through the testosterone studies some years back. Although men seem to "rev up" on testosterone in preparation for certain kinds of competitive events, the strongest demonstrated correlations are: 1) Stress or the experience of defeat tends to lower testosterone in men. (Is not starting a family stressful?) Some of the lowest aggregate testosterone counts recorded were for men about to be shipped off to war, by the way. 2) Men with lower testosterone counts tended to be deemed "less friendly" (more cranky?) by their peers; men with higher levels tended to be deemed friendlier, more likable. "The friendly, easy-going hormone?" I've never seen that one in the mass media, but it would reflect the more robust findings (subject to all the usual disclaimers about cause and effect, cultural context, and so on, of course). And that's some of the mess I dun "the trouble with nature...."

  2. Hi Daniel (and Roger)

    I agree with the general sentiment that science, including our study findings, is often simplified in problematic ways when pushed through the media prism. I also agree whole-heartedly that "there is always a complex interaction between biology and culture" – our study clearly shows that biology is not hard-wired but depends upon and responds to context (this is a key point of the study). In the article we review evidence that these responses vary in relation to cultural variation in fatherhood rolls, which is assumed by biological anthropologists who focus on these questions.

    As scientists, we have to walk a tight rope if our study generates media attention – we can provide journalists with nuanced and realistic statements that are invariably ignored, or we can shape the way our findings are presented to the public by picking our battles and simplifying our message. The points about testosterone that we tried to emphasize in each of our interviews is that 1) the behavioral effects of testosterone are notoriously unsettled and contentious, 2) that our best guess is that it has the effect of focusing one’s attention in ways that could be distracting to caregiving. Very little of the coverage treated these points with much nuance.

    In response to the challenges of communicating via sound bites, we spent quite a bit of time pulling together a longer blog post for Scientific American, which attempts to grapple with some of the history of the idea, the findings, possible interpretations, and limitations of current knowledge. Please check it out if you have time and interest:


    I would also recommend reading the original article itself, which provides quite a bit more detail and nuance than the media coverage. I’ve posted the pdf at my webpage, which can be downloaded here.

    It is gratifying to see our work generate thoughtful commentary like this – thanks for taking the time and for making us aware of your post.

  3. interesting story, nice blog and comments.. thanks for your concern about this. we should aware of our social life and take good care of our family.