Letter of Support for AAA’s Withdrawal of Session from the Annual Meeting

We are writing in support of the American Anthropological Association’s decision to withdraw the “Let’s Talk About Sex, Baby” session from the Annual Meeting. The session itself makes a number of claims that are counter to much of the settled science within biological anthropology and evolutionary biology more generally, throwing vague insults at the concept of “gender” without defining it in a meaningful way. Let’s look at some of the claims:

  • While some have focused on the session title, that is not our concern here except for the ways in which the title assumes a position within the field that is inaccurate.
  • The session writers offer up a concept of “biological sex” that is in contrast to “gender” without defining either term.
  • The session suggests that “gender” is being substituted for “sex” in anthropology. This is incorrect as there is currently massive work on these terms, and their entanglements and nuances, across social-cultural, biological, archeological, and linguistic anthropologies.
  • From the first presentation abstract, the authors use outdated terms such as “sex identification” rather than the more scientifically accurate term “sex estimation.”
  • Implicit in the session abstract and several of the individual abstracts is the assumption that sex is a biological binary; a concept that is rejected by current biological anthropology and human biology, and highly disputed across contemporary biology.
  • Most of the individual abstracts reflect grievances based on the erroneous assumptions outlined above.

As anthropologists who work in biological anthropology and human biology, we are aware that definitions of sex can be made using pelvic girdle shape, cranial dimensions, external genitalia, gonads, sex chromosomes, and more. Sex, as biological descriptor, is not binary using any of those definitions. People are born with non-binary genitalia every day – we tend to call people who fall into this group intersex. People are born with sex chromosomes that are not XX or XY but X, XXY, XXXY and more, every day. The same is true with gonads. What’s more, someone can have intersex genitalia but not intersex gonads, intersex chromosomes but not intersex genitalia. These bodily differences demonstrate the massive variation seen in sex physiology across vertebrate species. Looking beyond humans, we see three forms of the adult orangutan. Does this represent a sex binary? Significant percentages of many reptile species have intersex genitalia. Are we still trying to call sex a binary? The binary limits the kinds of questions we can ask and therefore limits the scope of our science.

As anthropologists, and human biologists, we also know that how people choose to name sex across genitalia, gonads, and genes is often culturally prescribed, and as this panel demonstrates, often politicized. Increasingly, many scholars, including researchers in the biological sciences, seek to understand sex and gender together in a recognition of their inherent entanglement. The integrated approach of gender/sex entanglement is a more realistic, albeit more complicated, view from which to ask and answer evolutionary questions for humans, and potentially other species, than has been the practice in human evolutionary biology.  Because, as Anne Fausto-Sterling writes, “few aspects of adult behavior, emotions, [sexuality], or identity can be sourced purely to sex or purely to gender,” because none of those qualities are fixed over a lifetime, and because “gendered structures change biological function and structure,” viewing gender and sex as entangled is a productive way forward.

The field of anthropology, and biological anthropology in particular, tends to resist universal arguments in favor of understanding humans in all of their variation. Therefore, the overprescription of the idea of a biological binary for something like sex not only ignores the evidence, but goes against the most basic empirical underpinnings of our field. Understanding human biological variation means resisting cultural norms around sex, instead of further entrenching them as the session authors have done here. Gender/sex is the inseparable development of anatomy, physiology, hormones, and genetics within a fluid sociocultural context including identity, roles and norms, relations, and power. Gender/sex acknowledges that culture seizes on baseline biological variation, shaping it, with the potential to increase it.

People who are non-binary, trans, or queer, and/or those who occupy sex categories other than “male” or “female,” have existed across all human societies and throughout all of human evolution. What is typical about human sex and gender categories, is that they are not simple, not binary, are always affected by the cultural beliefs of the time, and that they shift. To continue to work under such refuted assumptions is to work in the half-light, to miss most of the picture, and to not be engaging in rigorous, empirically grounded, and timely scientific anthropology.

Agustin Fuentes, Princeton University

Kathryn Clancy, University of Illinois

Robin Nelson, Arizona State University


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