“Wild cats are prolific and have few enemies; why then are they never as abundant as rabbits? The only intelligible answer is, that their supply of food is more precarious. It appears evident, therefore, that so long as a country remains physically unchanged, the numbers of its animal population cannot materially increase. If one species does so, some others requiring the same kind of food must diminish in proportion. The numbers that die annually must be immense; and as the individual existence of each animal depends upon itself, those that die must be the weakest—the very young, the aged, and the diseased,—while those that prolong their existence can only be the most perfect in health and vigour—those who are best able to obtain food regularly, and avoid their numerous enemies. It is, as we commenced by remarking, ‘a struggle for existence,’ in which the weakest and least perfectly organized must always succumb …” (Alfred Russel Wallace, “On the Tendency of Varieties to Depart Indefinitely from the Original Type” [Wallace’s contribution to Darwin and Wallace, “On the Tendency of Species to Form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection”], in Journal of the Proceedings of the Linnean Society: Zoology, Volume III [London: Longman, Brown, Green, Longmans & Roberts, and Williams and Norgate, 1859], pp. 56, 57.)24. In subsequent editions, the sentence was amended to read “Much light will be thrown on the origin of man and his history” (our emphasis).
Chapter 4
A GOSPEL OF DIRT
1. In Philosophical Works, with Notes and Supplementary Dissertations by Sir William Hamilton, with an Introduction by Harry M. Bracken, 2 volumes (Hildesheim: Georg Olms Verlagsbuchhandlung, 1967), Vol. 1, p. 52.2. Charles Darwin, The Origin of Species by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life (New York: The Modern Library, n.d.) (originally published in 1859) (Modern Library edition also contains The Descent of Man and Selection in Relation to Sex), Chapter XV, “Recapitulation and Conclusion,” p. 371.3. Of course, the traditional religious understanding of adaptation has been God’s will. However, this is not an explication of process.4. Unattributed quotations in this chapter are excerpted from Charles Darwin, op. cit., pp. 29, 31, 33, 34, 64–67, 359, and 370; and from Charles Darwin and Alfred R. Wallace, “On the Tendency of Species to Form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection,” Journal of the Proceedings of the Linnean Society: Zoology, Volume III (London: Longman, Brown, Green, Longmans & Roberts, and Williams and Norgate, 1859), p. 51.5. Francis Darwin, editor, The Life and Letters of Charles Darwin (John Murray: London, 1888), Volume III, p. 18.6. The Westminster Review 143 (January 1860), pp. 165–168.7. The Edinburgh Review 226 (April 1860), pp. 251–275.8. John A. Endler’s Natural Selection in the Wild (Princeton: Princeton University Press, 1986) provides a useful modern summary of what natural selection is and isn’t, its role in evolution, and how to test that it operates. His Table 5.1, culled from the recent scientific literature, summarizes over 160 “direct demonstrations” of natural selection in the wild.9. The North American Review 90 (April 1860), pp. 487 and 504.10. The London Quarterly Review 215 (July 1860), pp. 118–138.11. The North British Review 64 (May 1860), pp. 245–263.12. The London Quarterly Review 36 (July 1871), pp. 266–309.13. George Bernard Shaw, Back to Methusaleh: A Metabiological Pentateuch (New York: Brentano’s, 1929), p. xlvi. The last sentence is in fact the modern evolutionary point of view.14. James Watt, U.S. Secretary of the Interior in the first Reagan term, justified despoiling public lands on the grounds that he was unsure how much time we had “until the Lord comes.” Manuel Lujan, U.S. Secretary of the Interior under President Bush, argued against protecting endangered species because “[M]an is at the top of the pecking order. I think that God gave us dominion over these creatures … consider the human being on a higher scale. Maybe that’s because a chicken doesn’t talk … God created Adam and Eve, and from there all of us came. God created us pretty much as we look today.” (Ted Gup, “The Stealth Secretary,” Time, May 25, 1992, pp. 57–59.) Genesis urges us to “subdue” Nature, and predicts that “fear” and “dread” of us is to be upon “every beast.” These religious precepts have practical consequences in the human assault on the environment (cf. John Passmore, Man’s Responsibility for Nature: Ecological Problems and Western Traditions [New York: Scribner’s, 1974]). Leaders of a wide variety of religions have nevertheless taken forthright stands and political action to protect the environment (e.g., Carl Sagan, “To Avert a Common Danger: Science and Religion Forge an Alliance,” Parade, March 1, 1992, pp. 10–15).15. Alfred Russel Wallace, the co-discoverer with Darwin of evolution by natural selection—a generous and self-effacing man who described himself as “shy, awkward and unused to good society”—differed with him on one crucial matter. He was willing to accept that every beast and vegetable had so evolved, but not humans. Some divine (and self-reproducing) spark had to be injected at a comparatively recent date in the evolutionary process, he held. Wallace’s evidence?Unlike the racists of his time, Wallace was struck that the brain size and anatomy of all humans are sensibly the same: “The more I see of uncivilized people, the better I think of human nature, and the essential differences between civilized and savage men seem to disappear … We find many broad statements as to the low state of morality and of intellect in all prehistoric men which the facts hardly warrant.” (Quoted in Loren Eiseley, Darwin’s Century [New York: Doubleday, 1958], p. 303.) But pretechnological peoples, he thought, had no need of a brain able, say, to invent steam engines. So the human brain must somehow have been contrived early in order to perform complex adaptive functions much later. Such foresight, he well understood, was inconsistent with the fortuitous and short-term nature of natural selection. Thus, “some higher intelligence may have directed the process by which the human race was developed.” (Ibid., p. 312.)However, Wallace greatly underestimated the complexity of pre-industrial societies. There has never been a pretechnological human culture. Fashioning stone tools and hunting large animals are by no means easy. Big brains were an advantage to us from the start.Wallace was also transfixed by the spate of spiritualist demonstrations so popular in late Victorian England, including spirit rapping, seances, conversations with the dead, materializations of “ectoplasm,” and the like. These seemed to reveal a hidden spirit component of humans, but of no other living things. So far as we know, this heady brew was concocted out of equal parts skillful charlatans and credulous upper-class audiences. The magician Harry Houdini played an important role in later exposing some of these impostures. Wallace was hardly the only eminent Victorian to be taken in.When, toward the end of this book, we explore the extraordinary cognitive talents of chimpanzees as revealed in laboratory tests, a similar question occurs to us: How can they be preadapted to solve such complex problems? And the answer, or at least part of it, may be the same as for Wallace’s conundrum: In their everyday lives in the wild, chimps need a broad-gauge, multi-purpose intelligence—not nearly as advanced as what humans have, but much more than we might think.16. Nora Barlow, editor, The Autobiography of Charles Darwin (New York: Harcourt Brace, 1958), p. 95.17. James H. Jandl, Blood: Textbook of Hematology (Boston: Little Brown, 1987), pp. 319 et seq. See also David G. Nathan and Frank A. Oski, Hematology of Infancy and Childhood, 3rd ed. (Philadelphia: W. B. Saunders, 1987), Chapter 22.18. A. C. Allison, “Abnormal Haemoglobin and Erythrocyte Enzyme Deficiency Traits,” in D. F. Roberts, editor, Human Variation and Natural Selection, Symposium of the Society for the Study of Human Biology 13 (1975), pp. 101–122.19. Nora Barlow, op. cit., p. 93.20. An influential modern assessment from the Darwinian perspective of the behavior of animals in groups is E. O. Wilson’s Sociobiology: The New Synthesis (Cambridge, MA: Harvard University Press, 1975). The book in general excited little controversy, but the closing chapter—in which natural selection was applied to humans—elicited a storm of criticism, including the pouring of a pitcher of water over the author’s head at a scientific meeting. Wilson has taken care to stress that human behavior is the product of both hereditary and environmental influences, and has generally made his claims modestly and cautiously: “I might easily be wrong—in any particular conclusion, in the grander hopes for the role of the natural sciences, and in the trust gambled on scientific materialism … The uncompromising application of evolutionary theory to all aspects of human existence will come to nothing if the scientific spirit itself falters, if ideas are not constructed so as to be submitted to objective testing and hence made mortal.” (E. O. Wilson, On Human Nature [Cambridge, MA: Harvard University Press, 1978], pp. x-xi.)We can glimpse something of the fervor of this debate in the following, perhaps intemperate, remarks: “American social scientists fear and despise biology, although few of them have troubled to learn any … Again and again in the writings of social scientists, we find ‘biological’ equated with ‘Invariant’ … This usage betrays an incomprehension of the domain of biology.” (Martin Daly and Margo Wilson, Homicide [New York: Aldine de Gruyter, 1988], p. 154.)Excellent recent books on evolution for the general reader include those by Richard Dawkins (e.g., The Selfish Gene [Oxford: Oxford University Press, 1976]; The Extended Phenotype [Oxford: Oxford University Press, 1982]; The Blind Watchmaker [New York: Norton, 1986]) and by Stephen J. Gould (e.g., Ever Since Darwin [New York: Norton, 1977]; The Panda’s Thumb [New York: Norton, 1980]; Wonderful Life [New York: Norton, 1990]). By comparing these books, we can glimpse the healthy and vigorous scientific debate that thrives under the aegis of modern evolutionary biology.21. John Bowlby, Charles Darwin: A New Life (New York: W. W. Norton, 1990), p. 381.22. Francis Darwin, op. cit., Volume I, pp. 134, 135.23. Ibid., Volume III, p. 358.24. See, e.g., Leonard Huxley, Thomas Henry Huxley (Freeport, NY: Books for Libraries, 1969); Cyril Bibby, Scientist Extraordinary (Oxford: Pergamon, 1972).25. Cyril Bibby, T. H. Huxley: Scientist, Humanist and Educator (London: Watts, 1959), pp. 35, 36.26. Thomas H. Huxley, “On the Hypothesis that Animals Are Automata, and its History” (1874), in Collected Essays, Volume I, Method and Results: Essays (London: Macmillan, 1901), p. 243.27. Francis Darwin, editor, The Life and Letters of Charles Darwin (London: John Murray, 1888), Volume III, p. 358.28. Bibby, 1959, op. cit., p. 259.29. All quotations except that attributed to Emma Darwin at the end are taken from eyewitness accounts, although most were written down years and even decades after the event. A memorable essay on the debate, “Knight Takes Bishop?” is in Steven J. Gould’s Bully for Brontosaurus (New York: W. W. Norton, 1991). Our version of Huxley’s response to Wilberforce is from the recollections of G. Johnstone Stoney, who was present. (Stoney did pioneering work on the escape to space of planetary atmospheres, and was the first to understand why the Moon is airless.) It differs from Huxley’s own later recollection, which went like this: “If then, said I, the question is put to me would I rather have a miserable ape for a grandfather or a man highly endowed by nature and possessed of great means of influence, & yet who employs those faculties & that influence for the mere purpose of introducing ridicule into a grave scientific discussion—I unhesitatingly affirm my preference for the ape.” (Bibby, 1959, op. cit., p. 69.)