The book follows a series of articles published by Diamond, a physiologist, examining the evidence and its interpretation in earlier treatments of the related species, including cultural characteristics or features often regarded as particularly unique to humans.

In answering these questions, Diamond (a professor in the fields of physiology and geography) applies a variety of biological and anthropological arguments to reject traditional hegemonic views that the dominant peoples came from "superior" genetic stock and argues instead that those peoples who came to dominate others did so because of advantages found in their local environment which allowed them to develop larger populations, wider immunities to disease, and superior technologies for agriculture and warfare.

The Third Chimpanzee also examines how asymmetry in male and female mating behaviour is resolved through differing social structures across cultures, and how first contact between unequal civilizations almost always results in genocide.

This determines much of human behaviour: how we pick our mates, and how we organize society and child nurturing systems, leading to differing social structures in cultures such as Papua New Guinea, Kerala, and the Christian West.

It also considers questions of longevity – the previous generation dies because its biological clock shuts down metabolism and repair as to divert investment from the parent individual to that of the offspring.

Historically, Diamond argues such contacts between widely differing populations have very frequently culminated in the extinction of the disadvantaged groups like many Native American tribes, the Tasmanians, etc.

[5] A contemporary review of the work by Frans de Waal was published by the New York Times (March, 1992), who praises the wit and breadth of the author's approach to the subject matter.

[2] In 2021, Martin Gore, founding member and songwriter of British synth-pop band Depeche Mode, released an EP inspired by the book and named after it.