The biographies analyzed by the author are those of Barbara McClintock, a genetics expert who was belatedly awarded the Nobel Prize in Medicine in 1983; Rosalind Franklin, who played an important role in the discovery of the structure of DNA; Christiane Nüsslein-Volhard, a specialist in Developmental Biology; Mary Leakey, who proved Darwin's accuracy in placing the origin of humanity in Africa; and Lynn Margulis, considered "among the most stimulating and original thinkers in all of biology.".