Photograph by Phoebe Jones ’18

In 2014, the governing body for international track and field competitions banned Indian sprinter Dutee Chand from women’s races, claiming that the naturally high levels of testosterone in her body gave her an unfair competitive advantage. The case, which ignited an international controversy, raised questions that professor Rebecca (Beck) Jordan-Young has been addressing for years. She has spent her career studying issues of sex, gender, and sexuality, and much of her work has combated misunderstandings of how hormones work and their impact on sex difference. Jordan-Young and her colleagues viewed what was happening to Chand as the latest attempt by sports officials to define and police gender. “We saw this as an opportunity to shine light on laws and policies that are not only unethical, they’re scientifically wrong,” she says.

Jordan-Young, who is the chair of the Department of Women’s, Gender, and Sexuality Studies, has been a pioneer in research on the intersection of science and social differences, especially concerning gender. A specialist in study design and measurement, she has delved into controversial debates about whether our brains are wired to be masculine or feminine, the importance of gender in the practice of medicine, and the significance of hormones such as testosterone.

After graduating from Bryn Mawr College, Jordan-Young earned a PhD from Columbia in sociomedical sciences, an interdisciplinary field that combines the technical aspects of public health research—such as epidemiology, biostatistics, measurement theory, and research design—with social science approaches to health and medicine. Through close collaboration with other scientists over the past 20 years, she has gained additional research skills in neuroscience and endocrinology, as well as cultural anthropology and history.

She spent the early part of her career researching HIV/AIDS and urban health while running a street-outreach program to prevent HIV among drug users and sex workers. As she looked at behavioral research on sexuality, such as studies that claimed to find biological differences between heterosexual and homosexual men, she was amazed by how much of what she read was deeply flawed. “I began to think about all the ways the studies were biased—through their recruiting methods, their measures, through analytical strategies that were subtly slanted toward finding differences,” she recalls.

Her research also led her to be critical of some practitioners of gender-specific medicine, which promotes the idea that treatments should be tailored by gender. While she acknowledges that the women’s health movement offered an important critique of how medicine considers the male body to be the default “norm” when conducting studies, she has concerns about how gender-specific medicine functions in practice. “A lot of claims that go under the banner of gender-specific medicine are more ideological than based in nuanced, detailed science,” Jordan-Young says.

Her interest in gender issues—and her expertise in analyzing studies and statistics—led her to devote 13 years to dissecting the scientific literature on whether hormones make our brains wired to be masculine or feminine in some consistent, demonstrable way. The result was the 2010 book Brain Storm: The Flaws in the Science of Sex Differences , which analyzed virtually all published research that supports the claims that sex differences are hardwired.

“The history of the so-called sex hormones is a really fantastic example of how it’s been hard to absorb evidence that contradicted expectations that people had for these ‘essences of masculinity and femininity’—and how we have repeatedly forgotten the more complicated story about how testosterone actually functions,” Jordan-Young says. Her study found methodological weaknesses, questionable assumptions, and enormous gaps between ambiguous findings and grand conclusions in years’ worth of studies. She argues that far more rigorous, biologically sophisticated study of gender differences is necessary.

Jordan-Young’s expertise in neuroscience came in handy in her analysis. “Neuroscience is currently a crucial arena for public discourse on sex/gender, and it’s not easy to break with the mainstream, which is mostly very committed to a conventional view of sex/gender differences, and often quite blind to methodological errors and biases in research,” she says.

Jordan-Young’s current research— for which she received a Guggenheim Fellowship in April—focuses on exploring disagreements among scientists in different disciplines about how testosterone functions in the body. “Testosterone has taken on a life of its own in the culture,” she said. “When people say things like, ‘There’s too much testosterone in the room,’ they’re using the term as a shorthand for all sorts of things that are wrapped up with maleness: masculinity, aggression, male privilege, libido.” This cultural baggage has a tendency to impede our understanding of the science—something that Jordan-Young believes is in play in the Chand case. While testosterone is a potent biological substance, multiple studies have shown that it doesn’t equal maleness—or athletic prowess—in any sort of simple or obvious way.

In the Chand case, Jordan-Young argued in articles for The New York Times, Science, and other publications that elite athletes have many physical characteristics that distinguish them from the mainstream, but none of those other natural variations were being singled out. For example, women with complete androgen insensitivity syndrome, whose bodies are unable to process testosterone, often are taller than average and are overrepresented among elite athletes.

“Fairness means a level playing field, not level athletes,” she says. Chand has a condition called hyperandrogenism, which results in her body producing levels of testosterone that situate her in the male range in the view of the International Association of Athletics Federations (IAAF).

Using testosterone levels to determine who is allowed to compete is illogical, Jordan-Young argues, because there is no clear evidence showing that successful athletes have higher testosterone levels than less successful ones. “There is very little consensus among sport scientists about precisely what testosterone does, how important it is, and under which circumstances it’s important,” she says.

Jordan-Young and her colleagues’ work arguing for a more nuanced, complex understanding of hormones seems to be paying off: Last summer, the IAAF suspended its hormone testing rules for two years, allowing Chand to compete. But even if hormone testing is no longer permitted, cultural anxiety about gender persists. Sports is where much of that anxiety gets played out—despite the scientific consensus that sex is not one single thing in the body, and that there aren’t any bright lines that divide all males from all females.

“The ideal solution to worries about masculine women in sports would be for the sports organizations to actually take a positive step toward educating athletes and the general public about the range of natural variations among athletes,” Jordan-Young says. The biggest obstacle, however, may remain our cultural myths: “The folklore about testosterone doesn’t seem to get dislodged, even in the face of contrary evidence.”