[1] Rankin was born Joan Melvin Dowswell in Calgary, Alberta,[2] but moved with her family a year later to Regina, Saskatchewan.
During her childhood she took a drawing class at Regina College and was a member of her high school camera club; in her grade twelve year she took a course with Augustus Kenderdine.
She continued her studies with Kenneth Lochhead, and in 1954 was hired as the Saskatchewan Golden Jubilee graphic artist.
With Yves Gaucher and Alfred Pinsky she took lessons at Concordia University, which awarded her a master's degree in art education in 1969.
[3] Her work has been exhibited widely in Canada, both in solo and in group shows, and is held in numerous private and public collections.