While in graduate school, Lynn was impressed by her own professor, James F. Crow, who taught her General and Population Genetics. Her deep interest in the subject was founded here, and led her to believe that it was only through Genetics that the process of evolution could be reconstructed. 

Margulis was also inspired by her science courses in university, in large part because reading assignments in her school consisted not of textbooks or summaries of theories but rather, original works and writings of the world’s greatest scientists such as Isaac Newton and Gregor Mendel, which inspired her to think creatively and out of the box, and allowed her to ask and explore questions that she proceeded to pursue throughout her career. 

Even in her early days as a mere undergraduate, Margulis always questioned the commonly accepted theories of genetics, refusing to believe until she saw the evidence for herself, and challenged the traditionalists by presenting hypotheses that contradicted current beliefs.

Her passion for her work was so strong that it helped her withstand all criticism for her research and allowed her to establish a solid career in biological science. 

An interview with the late Lynn Margulis, where she talks about what led her to pursue evolutionary microbiology: