The shortened article version of Sarah Blaffer Hrdy’s Mothers and Others, included intriguing suggestions about male hormonal changes and testosterone after childbirth:
Anne Storey and colleagues in Canada have reported that prolactin levels in men who were living with pregnant women went up toward the end of the pregnancy. But the most significant finding was a 30 percent drop in testosterone in men right after the birth. (Some endocrinologically literate wags have proposed that this drop in testosterone levels is due to sleep deprivation, but this would probably not explain the parallel testosterone drop in marmoset males housed with parturient females.) Hormonal changes during pregnancy and lactation are, of course, indisputably more pronounced in mothers than in the men consorting with them, and no one is suggesting that male consorts are equivalent to mothers. But both sexes are surprisingly susceptible to infant signals–explaining why fathers, adoptive parents, wet nurses, and day-care workers can become deeply involved with the infants they care for. (2012:41)
In 2011 anthropologist Lee Gettler and colleagues delivered the longitudinal data from studies conducted in the Philippines. It isn’t sleep deprivation, damn those endocrinologically literate wags. Fatherhood really does lead to a testosterone drop. Garnering a nice bump in the press, the New York Times heralded a new era for testosterone anthropology: Fatherhood Leads to Drop in Testosterone.
The New York Times article featured extended quotes from several anthropologists appear in introductory anthropology textbooks and readers. The research is a great way to emphasize anthropological holism and to show how anthropologists push beyond culture-biology dichotomies. Lee Gettler and colleagues at Northwestern University have been developing this holistic biocultural approach, and received a nice bit of recognition for their work. This research also pairs nicely with Meredith Small, Our Babies, Ourselves. Another great tie-in to Small’s article is Gettler’s subsequent work on Does Cosleeping Contribute to Lower Testosterone Levels in Fathers? Evidence from the Philippines (2012), co-authored with frequently-cited co-sleeping advocate James McKenna.
Notably, baseline testosterone levels do not predict paternal involvement or co-sleeping, but the larger testosterone drop is found with the practice of co-sleeping and greater paternal involvement.
Testosterone Anthropology as great biocultural anthropology
Among the prominent anthropologists, in order of appearance in the New York Times:
Carol Worthman was not an author on the study but does get featured in the article. Worthman is a primary contributor to Slumber’s Unexplored Landscape which was in the 9th edition of the Applying Anthropology reader, but has unfortunately been dropped from the 10th edition. (Bruce Bower’s Slumber’s Unexplored Landscape is now only available for Science News subscribers. I do miss using it as an introduction to anthropology.) Worthman in the New York Times commented: “What’s great about this study is it lays it on the table that more is not always better. Faster, bigger, stronger–no, not always.”
Christopher W. Kuzawa is a co-author of the official study, Longitudinal evidence that fatherhood decreases testosterone in human males. Kuzawa is also a co-author for the 2012 co-sleeping study. Kuzawa’s work on maternal environment has been a crucial link in pushing beyond culture-nature divides–see Developmental Origins of Adult Function and Health (Kuzawa and Quinn 2009) and the discussion at the end of the section on Human Nature and Anthropology. Kuzawa was also a key source for how Clarence Gravlee discusses the inter-generational transmission of racial inequalities through health outcomes–see Gravlee’s How race becomes biology: Embodiment of social inequality (2009) and the discussion in the blog section on Race Becomes Biology, Inequality Embodied.
Sarah Blaffer Hrdy does not appear until the end of the New York Times article. I was initially puzzled Hrdy did not show up earlier, since this was something Hrdy alerted us to a long time ago. In the New York Times article, Hrdy poses an insightful question: “Are only biological fathers affected, or would similar results occur ‘if you have an uncle or brother or stepfather living in the household and they care for the baby?'”
Testosterone Anthropology, Concern #1: The new testosterone determinism?
My first concern with these kind of studies is a possible lack of appreciation for how much hormones, testosterone especially, are now becoming our new version of biological-genetic determinism. Just do a search on “testosterone anthropology,” or open your e-mail, or probably look at the Google ads popping up on my blog right now–there is a huge market for testosterone supplements, playing on the common perception that testosterone is such a key ingredient to masculinity.
In fact, the first line of the New York Times article is a kind of taunt: “This is probably not the news most fathers want to hear.”
I would like to see more emphasis on the social factors surrounding constructions of male and female sexuality, as well as expectations of parenthood roles.
For the most part the anthropologists in the current testosterone article do try to fight against testosterone causality and other possible misintepretations. From Lee Gettler, study co-author: “It could almost be demonized, like, ‘Oh my God, fathers, don’t take care of your kids because your testosterone will drop way down,’ . . . But this should be viewed as, ‘Oh it’s great, women aren’t the only ones biologically adapted to be parents.'” Also Carol Worthman gets a word in at the end: “If guys are worried about basically, ‘Am I going to remain a guy?’ . . . 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.”
For an anthropological blog-post that did take on these possibly deterministic tones, see Daniel Segal’s TESTOSTERONE & CULTURE: A Comment on Another Adaptationist Fable. The post includes a back-and-forth in which Kuzawa clarifies the research. Also, anthropologist Kate Clancy posted some great extended comments on this research, Parenting is not just for the ladies: on testosterone, fatherhood, and why lower hormones are good for you. Of particular relevance to the taunt of “not the news most fathers want to hear,” Clancy makes this trenchant observation: “What I have noticed missing from the stories about the most recent paper on testosterone and fatherhood is the fact that, from a survival perspective, testosterone is bad for you!” So, in fact, this is news most fathers should want to hear.
At Neuroanthropology, Daniel Lende has a great Interview with Lee Gettler. In general, the co-authors seem savvy to these concerns and media portrayals. However, I do worry that testosterone stereotypes are too strong to be overcome.
Testosterone Anthropology, Concern #2: Is a biocultural result from the Philippines generalizable?
Long before Jared Diamond popularized the idea of caution when extending results from WEIRD (Western Educated Industrial Rich Democracies) societies to the rest of the human species–see Ruth Benedict, Patterns of Culture–anthropologists have been hammering the theme that it can be very misleading to assume that results from any one group extend to all humanity. In this case, I do think we need some caution before we extend a study from the Philippines onto human fatherhood throughout time and space.
Of particular interest here is the follow-up study on co-sleeping, where we learn that fully 92% of the Filipino fathers are “same surface co-sleepers” (not just roomsharers, which was a separate category). Now, I know a lot more co-sleeping goes on in the United States than is generally reported, but wow: 92% as same surface co-sleepers! In other words, it certainly makes me wonder how much a fatherhood testosterone decline can be extracted from the co-sleeping testosterone decline, and how much either applies in places that do not normally practice so much same surface co-sleeping.
Despite these concerns–basically a plea to make sure we keep culture, power, and history in the mix as we work toward biocultural synthesis–this was some great work and a good media splash to demonstrate anthropology’s ongoing relevance.
Update: For thoughts on Hrdy see this 2022 Intro-to-Anthro lecture:
To cite: Antrosio, Jason. 2013. “Testosterone Anthropology: A Biocultural Synthesis with Mothers and Others.” Living Anthropologically website, https://www.livinganthropologically.com/testosterone-anthropology/. First posted 24 February 2013. Updated 1 November 2022.