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paleoanthropology, genetics and evolution

warfare

  • Dynamics of violence

    Sat, 2012-05-19 12:03 -- John Hawks

    This week's Science is a special issue focusing on human conflict. As you might expect, the issue includes an article focusing on Steven Pinker's book, The Better Angels of Our Nature: Why Violence Has Declined. The article is by Andrew Lawler, who talked with a number of bioarchaeologists who focus on violence and warfare in ancient societies [1].

    Pinker blames what he calls “anthropologists of peace” for distorting the record on small-scale group violence. “The classic ‘gentle people’”—the Semang of the Malay peninsula, !Kung in Africa, and Central Arctic Inuit—“turned out to have higher homicide rates than those of American cities,” Pinker says. He criticizes what he calls a single-minded determination “to make hunter-gatherers seem as peaceful as possible.”

    Such charges puzzle some biological anthropologists and archaeologists—the kinds of scholars who gather the type of data used in this debate. They do not argue for a Rousseauian perspective. But that doesn't mean they're ready to embrace a Hobbesian view, either. They find the data too weak to support such sweeping claims and add that the statistical averaging done by Pinker and Gat erases the enormous variation in small-scale societies. Pinker “misused the bioarchaeological record by selecting a few populations … biased toward supporting his argument,” complains archaeologist Gwen Robbins Schug of Appalachian State University in Boone, North Carolina.

    My oversimplified view of matters is that Pinker abstracts a single latent variable from the data on violence and aggression: violence appears to decrease as social complexity and hierarchy increase. The anthropologists here are arguing for a more complex, and possibly cyclical, relationship in which other factors besides social complexity are important. George Milner's example:

    He cites the example of the Hopewell culture of the 1st through 5th centuries C.E. in eastern North America, which appears to have been “socially permeable,” allowing traders to safely transport obsidian from sources in what is today Wyoming as far east as Ohio. Such ease of movement would have been unthinkable before and after that era, when violence between groups was more common. The interesting question, Milner says, is what changed. “To see this from a solely Hobbesian viewpoint misses the real story,” he adds. “We want to know why people switch from peace to war and back again.”

    Rousseau was wrong. The Pleistocene was never a peaceful state of nature.

    Hobbes is too simplistic. Violence in human societies is multidimensional and we perceive it differently depending on its cultural motivation. This is why every discussion of Pinker's thesis (including Lawler's) begins by acknowledging the industrial-scale warfare and mass killing of the 20th century. Such events mean something different than big-city crime. Pinker's generalization is correct, but why it is correct depends on how the social uses of violence have changed over time. Hunter-gatherer groups often used violence, in ways that varied among groups and across time to maintain sometimes-elaborate systems of social control. Pinker's generalization is incomplete, and its incompleteness may be explained by the multidimensionality of violence in human societies.


    References

    1. Lawler A. The Battle Over Violence. Science. 2012;336(6083):829 - 830.
  • Quote: Ruth Benedict on pugnacity

    Sun, 2012-04-29 16:39 -- John Hawks

    From the classic anthropology text Patterns of Culture by Ruth Benedict [1], a striking case of the "culture over nature" position:

    Warfare is not the expression of the instinct of pugnacity. Man's pugnacity is so small a hint in the human equipment that it may not be given any expression in inter-tribal relations. When it is institutionalized, the form it takes follows other grooves of thought than those implied in the original impulse. Pugnacity is no more than the touch to the ball of custom, a touch also that may be withheld.


    References

    1. Benedict R. Patterns of Culture. New York: Houghton-Mifflin; 1934.
  • Warfare, catastrophes, six of one, half dozen of the other

    Wed, 2009-06-10 17:30 -- John Hawks

    I'm reading through the paper by Samuel Bowles, "Did warfare among ancestral hunter-gatherers affect the evolution of human social behaviors?" I've done some work (cited in the paper) on population extinction and recolonization, so I'm reading carefully and checking parameters as I go. Personally, I'm skeptical that Pleistocene warfare would have spurred altruism. More on that later.

    Meanwhile, the first two paragraphs of the discussion stick out:

    The mortality data summarized in Table 1 are consistent with what is known about the Late Pleistocene from more indirect data. Frequent lethal intergroup encounters may reconcile two otherwise anomalous facts about hunter-gatherer demographics. Human population grew extraordinarily slowly or not at all for the 100,000 years prior to 20,000 years before the present (35, 36), yet under peaceful conditions foraging populations are capable of growth rates exceeding 2% per annum (37, 38).

    Further, the extraordinary volatility of climate during the Late Pleistocene (39) must have resulted in natural disasters and periodic resource scarcities, known strong predictors of intergroup conflict among hunter-gatherers in the historical record (40), and undoubtedly forced long-distance migrations and occasioned frequent encounters between groups having no established political relations.

    That's called the "everything but the kitchen sink" argument. Warfare stopped the population from growing! Warfare inevitably followed resource scarcities!

    Didn't any of the reviewers notice that, uh, resource scarcity limits population growth even in the absence of warfare? These two factors explain each other just fine. Warfare is mediated by resource scarcity and population growth, sure, but they don't constitute arguments in favor of widespread warfare in the Pleistocene, any more than they are arguments for widespread warfare in beavers and ducks. Every species in nature can grow fast when resources aren't limited, most a lot faster than us.

    References:

    Bowles S. 2009. Did warfare among ancestral hunter-gatherers affect the evolution of human social behaviors? Science 324:1293-1298. doi:10.1126/science.1168112

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