What is the essence of gender?

Can one indispensable factor define whether a person is male or female? In the last 100 years, we have moved toward a place of understanding and acceptance of variance in gender roles and recently also sexual orientation. However, we also have to consider the variance in the domain of gender identity. Vickie Pasterski, a psychologist specialising in behavioural neuroendocrinology, does research investigating hormonal influences on brain development. Beside teaching the subject, she has a clinical practice where she helps people whose gender identity does not match their body. In her talk she untangles the complexity of gender showing that our world is not just pink and blue but rather a kaleidoscope of full colour.