What is the theme in A Feeling for the Organism: The Life and Work of Barbara McClintock by Evelyn Fox Keller?

The capacity to be alone is a theme in the story. Barbara McClintock was a loner from birth, at least this was what she believed. Her sister Majorie reported that as a child, when McClintock was left alone, she never raised a fuss. And as she grew up, she found little need to interact with others. This was partly due to her mother's emotional distance due to stress but partly due to her natural constitution. McClintock notes that her happiest times in life were when she was alone. As she became a scientist, she worked alone.