Crossley was born in Johannesburg, the second daughter of a colonial civil servant.

In 1963 she graduated with a science degree from Cambridge University, and around the same time married her husband, Clive, a fellow scientist.

They moved to Australia, where Crossley earned a doctorate in the history and philosophy of science from the University of New South Wales in 1980.

[2] She contested Franklin in the 1993 federal election, the equivalent state seat in 1996 and 1998 and was the Greens' lead Senate candidate in Tasmania in 1998.

[3] Dr Crossley lived in Bruny Island, Tasmania, towards the end of her life and died in Hobart on 30 July 2015.