After spending many years as a teacher and librarian, Nettie Stevens, American biologist and geneticist born OTD in 1861, made a major scientific discovery later in her life: that an organism's sex is determined by its chromosomes. It's never too late to pursue your dreams. 🌠 . . . . . . . . #womeninscience #science #career #women #womancrush #genes #chromosome #biology #careerchange #lifegoals #goals #sciencegoals #inspiration #inspire #life #geneticist #scientist