In The Descent of Man, Charles Darwin stated, "At some future period, not very distant as measured by centuries, the civilised races of man will almost certainly exterminate and replace throughout the world the savage races." Based on this--and, of course, much, much more--evidence, I conclude that Darwin contributed to the development of theories of racial extermination that were prominent among leading German biologists and eugenicists in the early twentieth century. Despite Gliboff's dismissive comments about my book, most scholars agree with me that racial struggle is an integral part of Darwin's account of human evolution, and some even explicitly discuss the role of racial extermination in his theory.
Gliboff tries to marginalize my position by pretending that the source of my views is creationism, when I am sure that he knows--but somehow forgets to mention--that many, many scholars have reached conclusions similar to mine. For example, he criticizes me for "mak[ing] only cursory use of the extensive secondary literature on the origins of National Socialism and the history of Darwinism." He then produces a list of the literature on this topic, implying that I did not engage this literature. However, in my book I cited all the works he listed--plus many more he did not list--except for Peter Bowler's Evolution: The History of an Idea, which I have already cited in earlier publications. Also, the books he cites often support my position as much or more than his!
Also, Gliboff fails to mention that most of the literature on German eugenics, including books by Robert Proctor, Paul Weindling, Stefan Kuehl, and many others, discuss the linkages between Darwinism, eugenics, and Nazi ideology. Here is what Peter Weingart, Juergen Kroll, and Kurt Bayertz say in their highly regarded work, _Rasse, Blut, und Gene: Geschichte der Eugenik und Rassenhygiene in Deutschland_: "Ideengeschichtlich gesehen war der faschistische Staat eine logische Konsequenz jenes Zweigs der Eugenik, der dem sozialdarwinistischen Auslesegedanken verhaftet blieb" ("Considered from the viewpoint of the history of ideas the fascist state was a logical consequence of that branch of eugenics which remained bound up with social Darwinist ideas of selection"). I'm not claiming that all these Scholars would agree in every way with my analysis, but the connections between Darwinism and Nazism cannot be so glibly wished away, as Gliboff tries to do.
Moreover, a rich literature on German social Darwinism--beginning with a path-breaking essay by Hans-Guenter Zmarzlik, proceeding through Daniel Gasman (whose work is problematic), Peter Emil Becker, Juergen Sandmann, and moving on to more contemporary work by Mike Hawkins and Richard Evans--shows the way that social Darwinism in Germany paved the way for Nazism. Hawkins even spends an entire chapter showing the social Darwinist framework of Nazi ideology.
Further, Gliboff seems oblivious to the fact that it is a commonplace, uncontroversial assertion among most historians writing about Nazi ideology that social Darwinism was a central ingredient of Nazi ideology. Has he never read Detlev Peukert's essay, "The Genesis of the Final Solution from the Spirit of Science," or noticed that Ian Kershaw in his two-volume biography of Hitler repeatedly refers to social Darwinism as an integral part of Hitler's ideology? Other scholars noting the strong Darwinist link to Nazism (besides those I've mentioned above) include Eberhard Jaeckel, Brigitte Hamann, Michael Burleigh, and the list could go on.
Gliboff also fails to mention that on the issue of the connection between Darwinism and euthanasia, which is another significant topic in my book, Ian Dowbiggin and Nick Kemp in their recent books on the euthanasia movements in America and Britain agree wholeheartedly with my assessment. Not only that, but Udo Benzenhoefer in Der gute Tod? and Hans-Walter Schmuhl in Rassenhygiene, Nationalsozialismus, Euthanasie: Von der Verhuetung zur Vernichtung 'lebensunwerten Lebens' 1890-1945, both confirm the importance of Darwinism in shaping euthanasia ideology in Germany. Schmuhl even states: "Die rassenhygienische Paradigma konstituierte eine Ethik neuen Typs, die scheinbar durch die darwinistische Biologie wissenschaftlich abgesichert war" ("The race hygiene paradigm constituted an ethic of a new type, which was ostensibly grounded scientifically in Darwinist biology").
Now none of this proves that I have succeeded in my analysis, and perhaps some of these scholars I have mentioned will take issue with some aspects of my scholarship. Also, I'm well aware that not all Darwin scholars agree with my position on social Darwinism. Alfred Kelly in The Descent of Darwin, for example, denies or at least downplays the Darwinism-Nazi link (but he still contributed a nice blurb for my dust-jacket). Thus the controversy over social Darwinism and its role in the advent of Nazism is still a live debate, but I am confident--despite Gliboff and a minority that refuse to entertain the idea that Darwinism could possibly have produced unsavory political ideologies--that my position will ultimately prevail.
Finally, Gliboff's "dismay" about my work--heightened by the fact that it "is rich in primary material, thoroughly documented, and clearly and concisely written"--drives him to misrepresent my position at times. I cannot deal with all of these misrepresentations, but let me give just one glaring example of central importance. He asserts that the upshot of my argument is that "All else [besides God-given morality] leads to Hitler." Scholars will be happy to learn, however, that I overtly warn against such an interpretation, stating in the introduction, "The multivalence of Darwinism and eugenics ideology, especially when applied to ethical, political, and social thought, together with the multiple roots of Nazi ideology, should make us suspicious of monocausal arguments about the origins of the Nazi worldview" (p. 4). I later state, "Nor am I making the absurd claim that Darwinism of logical necessity leads (directly or indirectly) to Nazism" (p. 9) But Gliboff implies that I do make this absurd claim, which is all the more perplexing, since my earlier book, Socialist Darwinism, shows the impact of Darwinism on German socialist thought. I invite readers to find out for themselves why Gliboff is so worried about my book.
 Charles Darwin, Descent of Man, 2 vols. (Princeton: Princeton University Press, 1981), 1: p. 201.
 See Adrian Desmond and James Moore, Darwin (New York: Michael Joseph, 1991), pp. xxi, 191, 266-68, 521, 653; Robert M. Young, "Darwinism Is Social," in The Darwinian Heritage, ed. David Kohn (Princeton: Princeton University Press, 1985), pp. 609-638; John C. Greene, "Darwin as Social Evolutionist," in Science, Ideology, and World View: Essays in the History of Evolutionary Ideas (Berkeley: University of California Press, 1981); Peter Bowler, Evolution: The History of an Idea, revised ed. (Berkeley: University of California Press, 1989), p. 301; Gregory Claeys, "The 'Survival of the Fittest' and the Origins of Social Darwinism," Journal of the History of Ideas 61 (2000): pp. 223-40; I admit that some scholars, however, emphasize Darwin's abolitionist sentiments and sympathy for other races, e.g., Greta Jones, Social Darwinism and English Thought: The Interaction between Biological and Social Theory(Sussex: Harvester, 1980), p. 140; Paul Crook, Darwinism, War and History: The Debate over the Biology of War from the 'Origin of Species' to the First World War
(Cambridge: Cambridge University Press, 1994), pp. 25-28.
 Peter Weingart, Juergen Kroll, and Kurt Bayertz, Rasse, Blut, und Gene. Geschichte der Eugenik und Rassenhygiene in Deutschland (Frankfurt: Suhrkamp, 1988), p. 171.
 Hans Walter Schmuhl, Rassenhygiene, Nationalsozialismus, Euthanasie. Von der Verhuetung zur Vernichtung 'lebensunwerten Lebens' 1890-1945
(G=F6ttingen: Vandenhoek und Ruprecht, 1987), p. 2.