Review of Testosterone: An Unauthorized Biography. Rebecca M. Jordan—Young and Katrina Karkazis, Cambridge, MA: Harvard University Press, 2019, 289 pp.

Reviewed Book

Testosterone: An Unauthorized Biography. Rebecca M. Jordan—Young and Katrina Karkazis, Cambridge, MA: Harvard University Press, 2019, 289 pp.

This is a wonderful vivisection of a magic molecule, one that Jordan-Young and Karkazis show is a social molecule with a very particular history and role in contemporary life. For popular beliefs to take hold regarding testosterone’s determinative function in creating manly men, however, the hormone must be given the imprimatur of scientific fact. And while prime targets of the authors include newspaper nonsense and widely repeated biobabble about testosterone (or T, as aficionados call it), it is in the authors’ careful exegesis of scientific papers (and TED talks) touting T as the biological basis for masculinity that the book performs its most laudible educational and public service. Filled with careful readings and critique of major work in biology and chemistry on T, this book is timely and urgent.

A scenario typical of those the authors address is remarkable for its simplicity and shallowness: Find men who exhibit traits considered more manly (be they male soldiers, Wall Streeters, criminals, Southerners, acrobats); somehow find that these men record higher levels of T than the norm; and conclude that therefore T is the prime causal factor in masculinity and being more manly.

Such sleights of hand are exposed by Jordan-Young and Karkazis at multiple stages. What constitutes “more manly” is never discussed in these T-is-manly studies. Who is manly—and when—is not a universal given; when you get into the nitty-gritty of how T levels are measured (which the authors do with skill) most arguments about T’s miraculous properties fall apart; whether T levels are paramount or only part of the story and whether the mere presence of T is more salient in understanding its impact; how T affects different people differently at different times; and so on.

T here provides a classic case study of social prejudice overdetermining the course of scientific research and reinforcing preconceived, erroneous social beliefs, for example, about men and women. In chapters on violence, risk-taking, parenting, athleticism, and even ovulation, this biography of T refutes every significant claim about the hormone being the root of gendered differences, instead of viewing the vast majority of those differences as linked to social inequalities. The authors’ argument is important not so much for teasing apart biology from culture as it is for teasing apart the cultural bias in certain biologists’ claims that sexual dimorphism governs sexuality, aggression, compassion, and even prowess in sports.

The number of scholarly papers claiming a correlation between T and aggression grew tremendously in the decade between 2010 and 2019. This was not because of new discoveries regarding such a correlation, much less a causative relationship. Rather it was because of increasing popular, governmental (funding), and pharmaceutical (marketing) interest in T and the never-ending quest to identify the biological basis for male violence. Although the authors do not mention this spike in scientific publications on T, they do point to one of the few areas where there have been discoveries about the function of T in human biology: “that T may play a critical role in ovulation” (p. 38).

Saddled with the sobriquet “sex hormone” since the origins of modern endocrinology in the early twentieth century, the very idea that T might be crucial for females, and what’s more, female reproduction, runs against decades of mislabeling and mistaken identity. No idea about T has been more pervasive and obstinately held than the positive association between T and male reproduction, and the negative association between T and female reproduction. Yet as Jordan-Young and Karkazis note, “The singularity of T is an illusion, and the importance of context is profound” (p. 26). That T could be just as important for females as males cuts against the grain of much contemporary literature on the hormone.

As able historians of science, the authors situate not only the ideas but the power of the ideas about T in clear social context. They note, for instance, that “the foundational studies on T and human aggression date to a roughly thirty-year period from the 1970s through the 1990s” (p. 56). During this period, of course, there was a tremendous increase in the incarceration rate in the United States. Once it was no longer socially sanctioned to explicitly label men of particular races more dangerous, an end run was employed, using T as the means: Declare that, like it or not, some groups of men had higher T than others, and that higher levels of T were related to violent behavior, then, lo and behold, certain groups of men were imprisoned at record rates based on the pretext of their scientifically measurable T, not their race. The authors are not the first to remark that, in fact, when there is a correlation at all between T and aggression, it is aggressive behavior that causes T to rise, not elevated levels of the hormone that somehow cause men to rob, rape, and murder. As the authors explain, “Testosterone gives a modern, scientific explanation for the perennial trope of poor and working-class people as prone to deviant behavior” (p. 69). And, even more noteworthy, “It’s important to recognize the political and rhetorical importance that a long legacy of studies on T and criminality have in the scientization of current white supremacist views” (p. 81).

Through its meticulous review of everything from the Iowa Gambling Task (to determine risk-taking behavior, sometimes attributed to T in males), to “power posing” to elevate T and take charge in business and life in general, Testosterone builds on recent work by neuroscientists, psychologists, anthropologists, and others aimed at debunking myths about T. It delivers in one place a searing and persuasive contribution to our understanding of this social molecule, and why, “Too often, T is invoked as an apologia for a status quo sexism in which sexual violence, higher male salaries, men’s overrepresentation in prestigious occupations, and the tasking of women to domestic drudgery must all be accepted as natural and inevitable” (p. 215).

This study also will make it far more difficult to explain and excuse men (and women) who defend the gendered status quo using hackneyed biologisms.