What is the theme in A Primate's Memoir by Robert M. Sapolsky?

Another theme is growing up. The four parts of A Primate's Memoir are divided into periods of Sapolsky's young adulthood. While the story begins in his childhood, he goes to Africa for the first time as a college student. What is striking about the headings of each part is that it seems to take Sapolsky many years to become an adult. He does not even describe himself as an adult until he actually has an assistant professorship and is married. This self-characterization is significant.