Sex Is a Spectrum: The Biological Limits of the Binary

Reproductive anatomy is more variable than commonly understood, according to this eye-opening study. Fuentes (The Creative Spark), an anthropology professor at Princeton University, argues that many alleged sex differences are mirages born of cultural biases. For instance, he describes how archaeologists assumed a 5,000-year-old skeleton belonged to a man because it was surrounded by treasures, indicating high status, and possessed “typically male” pelvic bones, only for genetic analysis to reveal the individual had two X chromosomes. Rather than there being “two forms of human... there is a range of variation with some patterns in that variation,” Fuentes contends, noting that there are countless women who are taller than men despite the general tendency for the latter to be larger. The raft of research convincingly debunks the idea that sex anatomy has much consequence on behavior, character, or cognitive ability (one brain-imaging study found no significant differences in men’s and women’s “verbal, spatial, or emotion processing”), and the illuminating discussions of animal biology demonstrate the profound diversity of sex expression in nature, be it Okinawa pygmy goby fish that switch from “male” to “female” throughout their lives or female hyenas whose enlarged, erectile clitorises upset conventional wisdom about “female” mammalian anatomy. It’s a resounding refutation of the idea that there’s anything natural about the gender binary. (May)