When did the differentiation between sex and gender begin?

The differentiation between sex and gender gained prominence in the 1950s as researchers began to explore and highlight the distinctions between biological sex—referring to the physical characteristics such as chromosomes, hormone levels, and reproductive/sexual anatomy—and gender, which relates to the roles, behaviors, and identities that society constructs around those biological differences.

During this era, psychologists and sociologists started to point out that gender is not simply a reflection of biological sex; rather, it is a complex interplay of socialization, culture, and personal identity. This led to significant discussions in academia and beyond regarding how gender roles are influenced by societal norms and expectations, rather than being strictly determined by biological factors.

This understanding laid the groundwork for further exploration of gender identity, gender roles, and gender fluidity, leading to more nuanced perspectives in later decades. The importance of recognizing gender as a social construct began to take hold during this time, marking a pivotal shift in studies related to human growth and development.