The Third Chimpanzee

The Third Chimpanzee: The Evolution and Future of the Human Animal (1991), a nonfiction anthropological work by Jared Diamond, explores the origins of human behavior and cultural characteristics which are supposedly unique to humans. The Third Chimpanzee received the 1992 Royal Society Science Book Prize and the 1992 Los Angeles Times Book Prize for Science and Technology. Diamond is a Pulitzer Prize-winning author and is a professor of geography at UCLA. He is also an elected member of the National Academy of Sciences.

In The Third Chimpanzee, Diamond explores some fundamental questions. He tries to ascertain why some human groups dominate others and how this might be connected to better local environments, wider disease immunity, and enhanced technology. Diamond also considers why contact between “unequal” civilizations generally results in genocide. Humanity might be successful, but we are also prone to disaster.

There are broadly five parts to the book. The first considers our relationship with our closest relative, the chimpanzee. We are closer to chimpanzees than they are to gorillas, with the human genome varying by only 1.6 percent. Diamond reminds us that we should consider this when walking past chimps in zoos—we are their closest genetic relation. We can rightly be considered a third species of chimpanzee.



Parts 2 and 3 deal with sexual relationships and sexual selection between humans and other mammals. Interestingly, Diamond reveals that human females take far more care in selecting their mates than males do, probably because females must invest more energy in their children.

This pattern of selection influences a large part of human behavior. It influences how we choose sexual and romantic partners, friendship groups, childcare and child nurturing systems, and how we structure society. The pattern is responsible for the different structures between cultures.

Diamond also considers longevity. He notes that the human adult female’s body changes and its metabolism slows once there are offspring. This is probably because the body encourages energy being diverted from the older human to the offspring to better its chances of survival.



Part 3 considers how sexual and partner selection infiltrates so much of our culture, including art, language, music, hunting, and even agriculture. Diamond attributes this to something known as honest signaling—meaning, signals which benefit the signaler because they change the behavior of the mate or receiver in a positive way.

This works not only in courtship but also in everything from workplaces to social behavior—in fact, Diamond links drug and alcohol culture to honest signaling. However, Diamond doesn’t hold out much hope for us if we ever encounter extra-terrestrial intelligence, given our current structure and social cues would fail.

In Part 4, Diamond considers warfare and conquest. He wants to know why some human groups, such as Eurasians, came to dominate other groups, such as Africans. Diamond explains why this has nothing to do with genetic superiority of any kind but rather resulted from simple geography.



He explains that the Eurasian continent lends itself better to building large, sustainable populations, which in turn, become more resistant to disease. They also become a larger fighting force and reproduce more frequently. Diamond looks at the climate across the Eurasian continent and how temperate it is compared to the wildly imbalanced conditions of the African and American continents.

He explains that crop growth, domestication of animals, transport, and contact is much easier in temperate, predictable climates. If a geographically remote culture, such as a hunter-gatherer society, meets a larger-scale, agricultural culture, the former suffers most because of lesser disease resistance. In this sense, we’d be the so-called “less advanced” culture if we met extra-terrestrials.

Diamond then looks at how first contact between different societies led to the extinction of vulnerable groups, such as many Native Americans, Papua New Guinea highlanders, and Tasmanians. There are many such examples across history, and Diamond reflects on them.



This leads into Part 5, which considers extinction and its environmental impact. Diamond argues that, when societies become embroiled in their own wars and internal conflicts, they destroy their environment and can never fully recover. For example, they may clear too much forest or destroy the land, which can no longer sustain crops. Diamond doesn’t dwell too much on this topic, as it’s the theme of his 2005 book, Collapse: How Societies Choose to Fail or Succeed.

Diamond considers how close we are to disaster from destroying our own global environment, and how nuclear holocaust is possible in the future. He warns that environmental holocaust is already underway, and it’s becoming harder and harder to repair the damage done. Although the ending is somewhat bleak, the conclusion is a stark reminder of how our own internal wars across our wider global community are destroying the only home we all have.