Themes of A Primate's Memoir include community, stress, and development.

The baboon troop that Robert Sapolsky lives with isn't the only community in his memoir. Instead, he creates a community in Africa that supports and hinders his attempts to study the effects of stress on the baboon population. For example, his research assistants Richard and Hudson become lifelong friends, when they were only intended to be hired assistants. Sapolsky also meets Masai warriors and gets to know members of the tribe. As Sapolsky lives his life in Africa, he comes to know the people there and to become part of the community. Unfortunately, when corrupt men sell contaminated meat that ends up killing a great deal of the baboon population, he's unable to do anything about it. The system runs on tourism, and he's unable to convince even the people he knows locally to fight it.

Stress is another major theme in the work. Sapolsky himself faces a great deal of stress while studying the baboons. He falls prey to scams, doesn't get the money he is owed from his educational institution, and eventually loses more than a dozen baboons to contaminated meat. In the same ways that he theorized stress changes the brain and affects people physically, stress affects Sapolsky. It's clear that he's enraged about the fate of his baboons, but he's unable to do anything but feel that anger. He tries to fight the corruption that led to the contaminated meat being sold, saying:

I was going to have the information to save my baboons regardless of whatever powers that be, or, if I was going to lose my baboons, I was going to take everything down with them—Olemelepo, Safari Hotels and their owners, Timpai, the Kenyan tourist industry, the whole fucking country and its economy; my baboons were going to be avenged.

Ultimately, he isn't able to. As he grows older, he is able to cope with it better, but it never goes away entirely.

Development is another major theme in the novel. Sapolsky's own development takes place alongside that of the baboon troop. He goes to Africa for the first time as a young man on an adventure; he's there to follow his dreams. As he gets older, though, he stops studying as much of the behavior of the baboons. He begins to focus on practical things like grant funding, his wife, and the children they have. Part of this development stems from the pain of loss, but part is clearly also a natural consequence of growing up. Nowhere is this theme illustrated more strongly than in the section titles for the novel, which are “The Adolescent Years,” “The Subadult Years,” “Tenuous Adulthood,” and “Adulthood.” These are the life stages of baboons, but they also represent the development of Sapolsky himself.