'FURTHERREADINGS versity of Arizona Press, 1990), does the same for the decline of Petra, as does Robert Adams, Heartland of Cities (Chicago: University of Chicago Press, 1981), for Mesopotamia. A stimulating interpretation of the differences between the histories of China, India, Islam, and Europe is provided by E. L. Jones, The European Miracle, 2nd ed. (Cambridge: Cambridge University Press, 1987). Louise Levathes, When China Ruled the Seas (New York: Simon and Schuster, 1994), describes the power struggle that led to the suspension of China's treasure fleets. The further readings for Chapters 16 and 17 provide other references for early Chinese history. The impact of Central Asian nomadic pastoralists on Eurasia's complex civilizations of settled farmers is discussed by Bennett Bronson, 'The role of barbarians in the fall of states,' pp. 196-218 in Norman Yoffee and George Cowgill, eds., The Collapse of Ancient States and Civilizations (Tucson: University of Arizona Press, 1988). The possible relevance of chaos theory to history is discussed by Michael Shermer in the paper 'Exorcising Laplace's demon: Chaos and antichaos, history and metahistory,' History and Theory 34:59-83 (1995). Shermer's paper also provides a bibliography for the triumph of the QWERTY keyboard, as does Everett Rogers, Diffusion of Innovations, 3rd ed. (New York: Free Press, 1983). An eyewitness account of the traffic accident that nearly killed Hitler in 1930 will be found in the memoirs of Otto Wagener, a passenger in Hitler's car. Those memoirs have been edited by Henry Turner, Jr., as a book, Hitler: Memoirs of a Confidant (New Haven: Yale University Press, 1978). Turner goes on to speculate on what might have happened if Hitler had died in 1930, in his chapter 'Hitler's impact on history,' in David Wetzel, ed., German History: Ideas, Institutions, and Individuals (New York: Praeger, 1996). The many distinguished books by historians interested in problems of long-term history include Sidney Hook, The Hero in History (Boston: Beacon Press, 1943), Patrick Gardiner, ed., Theories of History (New York: Free Press, 1959), Fernand Braudel, Civilization and Capitalism (New York: Harper and Row, 1979), Fernand Braudel, On History (Chicago: University of Chicago Press, 1980), Peter Novick, That Noble Dream (Cambridge: Cambridge University Press, 1988), and Henry Hobhouse, Forces of Change (London: Sedgewick and Jackson, 1989). Several writings by the biologist Ernst Mayr discuss the differences FURTHERREADINGS • 457 between historical and nonhistorical sciences, with particular reference to the contrast between biology and physics, but much of what Mayr says is also applicable to human history. His views will be found in his Evolutionand the Diversity of Life (Cambridge: Harvard University Press, 1976), chap. 25, and in Towards a New Philosophy of Biology (Cambridge: Harvard University Press, 1988), chaps. 1-2. The methods by which epidemiologists reach cause-and-effect conclusions about human diseases, without resorting to laboratory experiments on people, are discussed in standard epidemiology texts, such as A. M. Lilienfeld and D. E. Lilienfeld, Foundations of Epidemiology, 3rd ed. (New York: Oxford University Press, 1994). Uses of natural experiments are considered from the viewpoint of an ecologist in my chapter 'Overview: Laboratory experiments, field experiments, and natural experiments,' pp. 3-22 in Jared Diamond and Ted Case, eds., Community Ecology (New York: Harper and Row; 1986). Paul Harvey and Mark Pagel, The Comparative Method in Evolutionary Biology (Oxford: Oxford University Press, 1991), analyzes how to extract conclusions by comparing species. credits p. 221: J. Beckett/K. Perkins, American Museum of Natural History.Negative 2A17202. p. 223: Otis Imboden, The National Geographic Society. p. 229: Courtesy of V.I.P. Publishing. p. 231: H. Edward Kirn, The National Geographic Society. pp. 232 and 233: The Metropolitan Museum of Art. p. 240: Heracleion Museum, Hellenic Republic Ministry of Culture. BETWEEN PP. 224 AND 225 Plates 1 and 8. Irven DeVore, Anthro-Photo. Plates 2-5. Courtesy of the author. Plate 6. P. McLanahan, American Museum of Natural History. Negative 337549. Plate 7. Richard Gould, American Museum of Natural History. Negative 332911. Plate 9. J. w. Beattie, American Museum of Natural History. Negative 12. Plate 10. Bogoras, American Museum of Natural History. Negative 2975. Plate 11. AP/Wide World Photos. Plate12. Judith Ferster, Anthro-Photo. 4 6 O •CREDITS Plate 13. R. H. Beck, American Museum of Natural History. Negative 107814. Plate 14. Dan Hrdy, Anthro-Photo. Plate 15. Rodman Wanamaker, American Museum of Natural History. Negative 316824. Plate 16. Marjorie Shostak, Anthro- Photo. BETWEEN PP. 256 AND 257 Plate 17. Boris Malkin, Anthro- Photo. Plate 18. Napoleon Chagnon, Anthro-Photo. Plate 19. Kirschner, American Museum of Natural History. Negative 235230. Plates 20, 22, 24, 30, and 32.