War and Sex, How Biology Explains Warfare and Terrorism and Offers a Path to a Safer World

by Malcolm Potts and Thomas Hayden, BenBella Books, 2008, 383 pages.

The first two thirds of the book describes the history of war beginning with pre-human ancestors. Jane Goodall was the first to describe team aggression in young male chimpanzees---we share a common ancestor with them. Jane Goodall was amazed by how young male chimpanzees frequently banded together to kill a lone member of a nearby troop. She never saw females participating in this. Our authors call this male coalitional violence and tellingly argue that it is even more obvious in human history and current events than in chimpanzees.

The universal precursor of male coalitional violence in chimps and humans is competition between adjacent groups for territory, food, and mates. Settled agriculture involved much larger groups and more wealth and was a prerequisite for modern warfare aggravated by periods of rapid population growth with a higher proportion of young relatively more testosterone “intoxicated” males less restrained by their elders. Bonobos, formerly called pigmy chimps, but recognized as a separate species since 1929, have a matriarchal social organization---male coalitional violence has never been observed in bonobos. They evolved from a common ancestor of ordinary chimpanzees by contriving to cross the two mile wide Congo River where they avoid their competition. A truly matriarchal human society has never been described by historians, anthropologists, or archeologists.

Periods of rapid population growth have preceded, if not caused, most warfare in humans. For recent examples, consider the time since the invasion of the new world by Europeans to the very recent Rwandan and Darfur episodes of genocide. Jared Diamond has emphasized this in his books Guns, Germs and Steel, and Collapse. In all human cultures men have tried to control female fertility, probably because males are content with quantity in reproduction, but females are more concerned with quality. Educated and prosperous women everywhere usually end up preferring two or three offspring.

What solutions do Potts and Hayden offer in Sex and Warfare? Here are some quotations from the book that address the question:

…..religions probably arose and persist because they unite large groups of people, and when it comes to fighting, the larger group usually wins…….Sam Harris in The End of Faith asks his readers to “imagine a future in which millions of our descendants murder each other over rival interpretations of Star Wars or Windows 98. Could anything—anything—be more ridiculous? Yet this would be no more ridiculous than the world we are living in”…….taking a biological perspective has a much better chance of success. Our survival as a species will not depend on divine intervention but on understanding our stone age behaviors. Once we do that, controlling them should become an achievable goal. (page 360-2)

We all share the desire to live in a world without wars and terrorism. But ignoring reality will get us no closer to that goal. If we truly want to attain peace, we first have to make peace with the fact that the behavioral building blocks of war are indeed to be found in our nature. …practically any young man can be transformed into a soldier, as the history of conscription and military training demonstrates….Solzhenitsyn’s insight that “the line dividing good and evil cuts through the heart of every human being” comes much closer to capturing human nature than anything {else}…. Raids and wars are not deviant activities; they are the logical expression of deep-seated behavioral predispositions. The impulses underlying warfare are universal, but happily, they need not be universally expressed…

…Intellectually tenable and politically realistic objections to slavery are historically recent, but they have been wonderfully effective.

Men are evolved to be territorial and competitive, and to engage in team aggression. Women usually lived in territories men carved out, and benefited more through in-group cooperation and social stability than through out-group hostility and aggression. If evolution provides the poison root of warfare, it has also supplied an important antidote. We overlook women’s powerful evolutionary heritage at our collective peril. (page 368-70)

In a generation’s time it is likely Iran will have nuclear weapons, but because family planning is now available; and women, on average, are having only two children and are moving toward greater equality, Iran will be much less likely to use these bombs than Pakistan, where families are twice as large and unemployment rampant. (page373)

{in Bangladesh} When asked in surveys how many children they want, most young couples today say “two.” Crucially, this includes most young men as well as their wives. What was the reason for this success in Bangladesh? A range of contraceptives has been offered and in many cases literally carried to women’s doorsteps. (page 375)

Malcolm Potts is an M.D., specialist in human fertility, the first medical director of the International Planned Parenthood Federation (1968), and professor at the School of Public Health, University of California at Berkeley. In early 1972 he was invited by the new government of Bangladesh to help with the plight of women made pregnant by rape during the war for independence from Pakistan which ended in December 1971. He deserves a prize for his very successful work there. Thomas Hayden is an experienced science journalist coauthor of On Call in Hell: A Doctor’s Iraq War Story in 2007.

John A. Frantz, MD, November 16, 2009