In Our Inner Ape, Frans de Waal — a leading primatologist — entertainingly and thoughtfully ponders what we can learn about ourselves from the behavior of our closest relatives: chimpanzees and bonobos. NCSE's Anne D. Holden writes (in RNCSE 2007 Sep–Dec; 27 [5–6]: 45–6), "de Waal's argument that humans exhibit important qualities of both chimpanzees and bonobos is well-developed, organized, and is complemented by excellent examples from his years in close contact with these animals. As a result, the reader is left with a solid understanding of what it means to be human, as well as what it means to be an ape."