Although there are ongoing debates and critiques around gender stereotypes, the world to date seems to be pretty comfortable with the idea of there being just two discrete biological sexes. But emerging evidence suggests this simple binary is nothing more than the result of a human need to organise our world into uncomplicated categories.

A core issue in this debate too often overlooked is the distinction between the definition of sex as opposed to the definition of gender.

Perhaps we want to limit the term ‘sex’ to fundamental biology – genes, genitals and gonads – and the term ‘gender’ to social processes. But it’s not so easy to separate the scientific and social context of these discussions.

Biological essentialism holds that social gender is driven by biological characteristics, to the extent that we need only use the term ‘sex’. On the other hand, discussions of gendered environments emphasise their powerful brain-changing effects, to the extent that gender has replaced sex as the catch all term.

In the recent IAI.tv debate The Rise and Fall of Sex, neuroscience appears the most prepared to tackle this distinction. Taking characteristics of both brain and behaviour that might be categorised as ‘typically female’ or ‘typically male’, Daphna Joel outlines powerful evidence that each of us is, in fact, a mosaic of different such characteristics, with very few of us describable as even predominantly male or predominantly female.  A game changer in decades of debate about the existence of only two types of brain – male or female -   she urges us to ‘think outside the box’, to go beyond the binary and acknowledge the uniqueness of each individual. There is no such thing as a female brain, there is no such thing as a male brain.