Explores what our two closest relatives in the animal kingdom -- the chimpanzee & the bonobo -- can tell us about our own human nature. Here is a lively look at the most provocative aspects of human nature -- power, sex, violence, kindness & morality -- through our two closest cousins in the ape family. For nearly 20 years, Frans de Waal has worked with both the famously aggressive chimpanzee & the lesser-known, egalitarian, erotic, matriarchal bonobo, two species whose DNA is nearly identical to that of humans. He brings these apes to life in this book, revealing their personalities, relationships, power struggles & games. An engrossing narrative that explores what their behavior can teach us about ourselves & each other. Illustrations.