Book Notes
The Third Chimpanzee by Jared Diamond — review and summary
Jared Diamond's argument is that humans are a third chimpanzee — 98 per cent genetically identical to our nearest relatives — and that understanding our evolutionary inheritance is essential for understanding our present behaviour.
Jared Diamond is a biologist, anthropologist, and author who has spent his career thinking about the evolutionary and ecological origins of human civilisation. The Third Chimpanzee is his early attempt to apply evolutionary thinking to a broad range of human behaviours — predating the more famous Guns, Germs, and Steel by several years.
The thesis
The title refers to the genetic data: humans share roughly 98% of their DNA with chimpanzees and bonobos. The implication Diamond draws is that the differences between humans and our nearest relatives are, in genetic terms, very small — and that understanding human behaviour requires understanding how we are continuous with our evolutionary past as well as how we are distinct from it.
The evolution of human distinctiveness
The first section of the book covers the features that distinguish humans from other animals: upright walking, language, art, tool use, and the capacity for culture. Diamond covers how each of these may have evolved and what the fossil and archaeological record tells us about the sequence.
The language chapter is particularly strong. Diamond covers not only the evolution of speech but the broader question of what language enables — specifically, the transmission of complex information across time, which is the foundation of cumulative culture.
Human sexuality and pair bonding
A significant portion of the book covers human sexuality from an evolutionary perspective: why humans have the pair-bonding patterns they do, how they compare with other primates, what the evidence suggests about the evolutionary functions of various human sexual behaviours.
This material is presented as biology, not social prescription. Diamond is careful about the distinction between what is and what ought to be — the naturalistic fallacy is explicitly addressed.
The dark side
Later sections of the book cover what Diamond calls the dark side of human evolution: the tendency toward genocide, the history of environmental destruction, and the agricultural revolution as a transition that, in many respects, made individual human lives worse rather than better.
These chapters are uncomfortable and deliberately so. Diamond's argument is not that these tendencies are inevitable but that they are predictable from evolutionary history, and that preventing their expression requires conscious effort.
Who this book is for
The Third Chimpanzee is most useful for readers interested in evolutionary biology applied to human behaviour, or for readers who want an accessible introduction to Diamond's thinking before reading the later works.
Practical reflection prompts:
- In which areas of your behaviour do you notice evolutionary inheritance that does not serve your conscious values?
- What does it mean to act consistently with what you believe rather than with what feels automatic?
Bibliographic details
- Author: Jared Diamond
- Published: 1991 (revised and abridged edition 2006)
- Publisher: HarperCollins