Biological sex is neither binary nor a spectrum – a biologist explains how it’s multidimensional

A biologist argues that biological sex is neither a strict binary nor a simple spectrum, but a multidimensional mosaic of traits that overlap between people categorized as female and male.

The piece walks through chromosomes, gonads, genitals, hormones, and secondary traits like body hair and voice pitch, noting that intersex variations occur in an estimated 0.2% to 6% of the population depending on definitions used.

It also notes that institutions like the International Olympic Committee have repeatedly changed how they test the sex of female athletes, most recently reverting to chromosome testing in March 2026, despite chromosomes alone not reliably predicting athletic advantage.

The full dispatch is available from the source below.