In response to:

How Fit Is E.O. Wilson’s Evolution? from the June 21, 2012 issue

To the Editors:

In his review of The Social Conquest of Earth [NYR, June 21], Steven Mithen begins with a very complimentary review of my life in science, which I appreciated—even though it sounds a bit like a eulogy. Then, suddenly, he declares how “awfully disappointed” he is by what he perceives as errors in archaeology. Now, I am very open to correction in particular disciplines, since in constructing the total argument I admit I was spread thin, all the way from molecular genetics to cognitive psychology and the neurobiology of music—as well as, incidentally, Steven Mithen’s own views on the evolution of mind. However, I was startled by the vehemence of Mithen’s criticism. I was even more surprised by the inaccuracy of the examples he chose from the book.

I’ll grant that I should have said “early” instead of “earliest” artifacts in reference to the production of points and arrowheads. Further, when Mithen speaks of many of the hand axes made by Homo erectus as being “quite exquisite,” not crude as I said, he makes an aesthetic judgment I can’t bring myself to share. Much more seriously, however, he misquotes me as saying, “Axes and adzes [were] invented in the Neolithic.” What I actually said was entirely different: “The mastery of stone was completed, taking toolmaking far from the simple knapping of available stones used in the Mesolithic to a far more sophisticated procedure. Axes and adzes invented in the Neolithic were made by a series of steps.” Which I then spelled out.

Misled by his mistake, Mithen referred me to “any undergraduate textbook” for enlightenment. He also sent me there to correct my supposed error in saying, “Neolithic toolmakers invented the concept of a hollow structure, with an outer and inner surface.” In my research for the book, I had actually done much better than that. I consulted the original research on this subject by the paleoanthropologists Dwight Read and Sander van der Leeuw (Philosophical Transactions of the Royal Society, B 363: 1959–1968, 2008), cited in The Social Conquest of Earth.

Far more serious is Mithen’s careless walkover of my treatment of prehistoric warfare. The considerable evidence I reviewed, and treated cautiously, justifies my conclusion that warfare and mass murder were commonplace, not “quite rare” as believed by Mithen. This judgment is bolstered by the archaeologist Steven A. LeBlanc in Constant Battles: The Myth of the Peaceful Noble Savage (St. Martin’s, 2003) and, earlier, Laurence H. Keeley’s War Before Civilization (Oxford University Press, 1996). (None of these scientists needed the guidance of undergraduate textbooks either.) Equally important, and not mentioned by Mithen, is the quantitative review of prehistoric and historical warfare among hunter-gatherers by Samuel Bowles, detailed in The Social Conquest of Earth. The mortality rates due to warfare were high enough to be a driver of group selection.

Steven Mithen concludes with a question written in astonishment: “How could E.O. Wilson of all academics write a book with a chapter entitled “Tribalism Is a Fundamental Human Trait’?” Answer: because massive evidence from multiple disciplines suggests that it is true. Mithen is a distinguished scholar in his own field. I wish he had written a more accurate and fair-minded account of my own recent work.

Edward O. Wilson
Museum of Comparative Zoology
Harvard University
Cambridge, Massachusetts

Steven Mithen replies:

I must apologize to Professor Wilson if he thought that my criticisms of his book were written with “vehemence.” That was certainly not my intention. I simply wished to correct what I believe to be errors in his text. Because these were numerous, I had to be succinct. This may have provided a misleading impression of being overly severe, which I regret.

With regard to hand axes, Professor Wilson is of course entitled to refer to a near-perfectly symmetrical, delicately flaked specimen as “crude” if he so wishes. But that strikes me not only as a misuse of the English language but as providing a false impression to his readers. Those unfamiliar with such artifacts might like to consult the undergraduate textbook The Human Past (edited by Chris Scarre, Thames and Hudson, 2005, pp. 93–96), which has an illustration of a hand axe found by John Frere at Hoxne in 1797 for which the term “crude” would seem inappropriate. Many other hand axes can quite reasonably be described as “crude”: quite why some show exquisite craftsmanship and others do not is an issue much debated by archaeologists, one that is reasonably accessible in the literature.

Professor Wilson’s statement regarding Neolithic axes and adzes cited in his letter continues to be inaccurate and I struggle to accept that my minor paraphrasing constitutes a misquote—but if he believes that to be the case then I apologize for being too inattentive to detail. The simple fact, however, is that while Neolithic axes and adzes were indeed produced by a “series of steps,” as he writes, so too were axes and adzes and other tools made and used during the earlier Palaeolithic and Mesolithic. A hand axe, in all these periods, required a sequence of hard hammer roughing-out and then soft hammer percussion. A Mesolithic arrow, to take another example, required the preparation of a blade core, removal of blades, the shaping of these into microliths, the preparation of a wooden shaft and resin, and then the combination of these to produce the arrow.

Contrary to what Professor Wilson writes, stone tool technology tends to be less rather than more sophisticated in the Neolithic. That of the Mesolithic went far beyond “simple knapping.” Having been excavating and analyzing Mesolithic technology for more than twenty-five years I am confident that this is not merely my own subjective judgment. Readers might like to consult the passage regarding stone tool technology in the undergraduate textbook Archaeology: Theories, Methods and Practice by Colin Renfrew and Paul Bahn (Thames and Hudson, fifth edition, 2008, pp. 323–332).

With regard to the proposition that “Neolithic toolmakers invented the concept of a hollow structure, with an outer and inner surface,” I suspect that the Palaeoindian hunter-gatherers from the Great Plains who made baskets and the Epi-Palaeolithic hunter-gatherers from the Near East who made stone bowls and mortars would disagree (see Scarre, The Human Past, pp. 209, 311). So too would those hunter-gatherers who built boats that enabled them to colonize Australia around 40,000 years ago. Regrettably, none of these pre-Neolithic hunter-gatherers will have read the article in the Philosophical Transactions of the Royal Society to which Wilson refers.

The subject of prehistoric warfare is complicated, remaining subject to considerable debate by archaeologists (see Renfrew and Bahn, Archaeology, pp. 218–219). The books by Keeley and LeBlanc cited by Professor Wilson were valuable contributions and exposed a higher degree of conflict in some parts of the prehistoric world than had previously been appreciated, most notably in the American Southwest. But the extent to which their conclusions can be generalized to the entirety of prehistory, and hence warfare cited as an endemic state of the humankind, is problematic. Readers might like to consult the set of essays in The Archaeology of Warfare: Prehistories of Raiding and Conquest (University of Florida Press, 2006), several of which challenge the claims by Keeley and LeBlanc. (Brian Ferguson’s essay is particularly good.)

The key issues raised in these challenges include: the extent to which conflict among ethnographically documented hunter-gatherers can be used as a model for the prehistoric past; distinguishing between interpersonal violence and planned group action that amounts to war; distinguishing between fortifications and weapons that were made for symbolic display rather than bloody conflict; the absence or immense scarcity of evidence for conflict in a substantial element of the archaeological record.

These issues are especially pertinent to the work by Samuel Bowles that Professor Wilson says he has “detailed” in The Social Conquest of Earth and that he appears to think I should have mentioned. I am pleased to have this opportunity to do so. Wilson reproduces the table from Bowles’s 2009 article in Science on “warfare among ancestral hunter-gatherers” that lists the data on which Bowles has drawn. What Wilson does not do in his “detailed” exposition is note that Bowles had stated that “whether ancestral humans were largely ‘peaceful’ or ‘warlike’ remains controversial” and admit that his own data from the late Pleistocene and early Holocene may be unrepresentative, partly because they derive from a period of extremely volatile climate change. It is indeed the atypical nature of Bowles’s archaeological data set that should have concerned Wilson.

As one can see from the table reproduced in The Social Conquest of Earth, Bowles’s sample is dominated by relatively recent Holocene hunter-gatherers from the Northwest Coast of America (sixty-two of seventy-two archaeological sites). Those hunter-gatherers are known to have been quite exceptional. A standard introductory book by two leading archaeologists of this region states:

The societies of the Northwest Coast differed markedly from the common stereotype of hunter-gatherers. They were the most socially complex hunting and gathering societies known on earth and had social and cultural features, such as social stratification, that are usually assumed to be attributes of farming people.

They continued to describe how such hunter-gatherers were sedentary, lived in large villages and towns, had full-time specialists, ownership and control of property, and monumental architecture. The basic reason for such complexity was the abundant resources from the Pacific Ocean, enabling salmon to be harvested in the manner that farmers harvest crops (although read Ames and Maschner for a more subtle explanation). In such conditions one might expect conflict to arise.

Three of Bowles’s remaining sites come from the Late Mesolithic of Northwest Europe. This is known to be a period when the indigenous hunter-gatherers were coming under combined pressures of landscape change from rising sea level and contact with Neolithic farmers who had spread into the region from central and southern Europe. Both destabilized the hunter-gatherer societies, leading to intra- and inter-group conflict (for an account see Mithen, After the Ice, 2003, chapter 20). Similar pressures occurred within those hunter-gatherer societies that came into contact with state societies in the late nineteenth and twentieth centuries, some of which constitute Bowles’s ethnographic sample.

I am not sufficiently familiar with the remaining seven archaeological sites that Bowles draws upon to provide a comment. My key point is that to understand conflict in hunter-gatherer societies (or indeed any society) one needs to explore the social, economic, and environmental conditions that may result in what Wilson described as “tribalism” becoming expressed. Current evidence suggests that such tribalism was rare throughout prehistory other than in the exceptional circumstances that I have described above. I’m afraid that if there has been a “careless walkover” of the evidence for prehistoric warfare, it was in The Social Conquest of Earth and not my review.

I hope that I have not appeared vehement in my response to Professor Wilson’s letter. I found a great deal to admire and enjoy in his book and I am delighted that biologists are drawing on archaeological evidence when addressing fundamental issues about human nature and society. The evidence is, however, complicated and often difficult to interpret. The need for accuracy and fair-mindedness is an obligation on all writers, authors as well as reviewers. I trust that Professor Wilson will accept my challenges to his views about the past as part of a constructive academic dialogue in our shared quest to understand humankind.