Lynn Margulis was born in 1938 in Chicago. She was the first wife of astronomer Carl Sagan. She was fascinated by genetics right from youth and looked at theories from the 19th century, based mostly on zoological arguments, in the light of modern microbiology. She was the originator of Endosymbiotic theory, which proposed that eukaryotic life (cells with a nucleus) evolved as gardens of simpler prokaryotic life (such as bacteria). This was indeed a fringe theory when it was proposed, but due in equal parts to her tenacity and subsequent microbiological evidence supporting it, it is mainstream today. She continues to argue radical theories to this day.
Her respect for others’ work that is many years, even many decades old is refreshing in the modern world. Margulis is also an example of how “even when spoken by a minority of one, the truth is still the truth”, an important principle of science.