When a child is born, a doctor or midwife takes a quick glance at the baby’s genitals and declares the baby a boy or a girl accordingly (unless the doctor or midwife notices during their quick glance that the baby is intersex…). But in day-to-day social situations, we don’t flash our genitals at each other! Instead, we determine the gender of other people in the first seconds of meeting by unconsciously observing and analysing a huge number of different gender-associated cues like clothes, body shape, voice, face shape, mannerisms and behaviour. We also signal our own gender using these cues. For the majority of people, these different gender-associated cues all match up closely with the gender they actually identify as, but for a minority not everything matches up as expected.
It can feel uncomfortable and difficult to suddenly try to think in depth about something usually determined easily without any conscious thought. But a useful way to think about gender without causing too much of a headache is to use the diagram shown below. It helps you to think about the differences between gender identity and expression, sex assigned at birth, and sexual and romantic attraction.
Throughout history, small but significant numbers of people have found that their sex assigned at birth, gender identities and gender expressions do not all match up in the way society would expect. For every imaginable combination of positions on these five scales, there are currently a number of people in the UK for whom that combination is their daily experience of their gender and sexuality. Unfortunately, while nature loves variety, society tends to prefer similarity so there is often a lot of pressure, in the form of harassment and discrimination, to try to force people not to reveal any gender variance.