As many have noted, the Intelligent Design movement’s echo chamber has been recently belaboring the connection between Darwinian evolutionary ideas and eugenics. That’s not surprising: the Discovery Institute-headed machine has been on the ropes for a while, unable to make any significant scientific, legal or political headway against evolution science (a.k.a. “Darwinism” in ID/Creationist parlance), and it has naturally turned to what it does best, that is media-based attack campaigns on straw-man stand-ins for evolutionary biology.
The transparent goal of this new P.R. offensive is to tarnish 150 years of scientific discovery with the stain of one of its aberrations, the logical equivalent of attacking experimental medicine by claiming that it is based on analogous principles as Josef Mengele’s experiments in Nazi concentration camps. Oblivious to logic and intellectual honesty, the “Darwinism = eugenics” meme nevertheless has been widely promoted by several ID advocates, most prominently by John G. West, Associate Director of the Discovery Institute’s Center for the Renewal of Science and Culture.
West’s argument is not particularly subtle. Not only he points out that “eugenics was in reality a reasonable deduction from Darwin’s theory” , which depending on interpretations may not be not too far off, but he actually argues that eugenics is a necessary consequence, a “corollary”  of evolutionary biology and “thoroughly grounded in the principles of Darwin’s theory” . The Discovery Institute’s President Bruce Chapman echoed the same sentiments, stating that “eugenics was not just connected to Darwinism, but derived from Darwin’s own work”  (emphasis mine). I guess the idea is that by pointing out its necessary evil consequences, people will turn against “Darwinism” whether or not it is scientifically supported (moral choices should apparently trump reality in the Discovery Institute’s brave new scientific world).
Minor and even less subtle ID characters have then jumped in to dutifully amplify the sound-bite, but doing so have inadvertently exposed the religious motivations behind the argument. Thus, human April Fool’s joke and neurosurgeon Michael Egnor has not only claimed that eugenics’ “modern scientific foundation is Darwinism”  (though bizarrely claiming elsewhere that selective breeding, the main tool of eugenics, is an application of ID principles), but also that “[t]he ideology that drives Darwinism and eugenics is materialism”  and “[t]he basis for eugenics was philosophical materialism, which denied the inherent dignity and sanctity of every human life”. Hatchet-wielding ID-friendly journalist David Klinghoffer, writing in the Weekly Standard, upped the ante with characteristically hammy rhetoric:
The major ethical impact of the Darwinian idea has been to undercut what contemporary Princeton bio-ethicist Peter Singer decries as the “Hebrew view” of a purposefully-designed humanity, crowned by the solemn and central theme: “And God said, Let us make man in our image.” 
(Go ahead and tell us how the “Hebrew view” of the crowning solemnity of God-given human dignity applied to the Amalekites, Mr. Klinghoffer.)
Of course, the origins and history of eugenics are far more complex and nuanced than this. The modern eugenics movement certainly drew much of its scientific aura and justification from Darwinian ideas, especially as the latter became more and more supported and accepted. But eugenics also stemmed from Mendelian genetics, with its static view of genetic transmission, and from the rising prestige of scientific medicine and medical psychiatry in the early 20th century. In addition, the rise of eugenics was fed by traditional views on “bloodlines” and hereditarianism, Victorian ideas on class and aristocracy, conservative socio-economic theories, positivist philosophy, racism and anti-immigrant sentiment in the US, etc.
In fact, eugenics is pretty much as old as human society, and pervasive throughout its history. Most cultures of course have prohibitions against incest, and several US States still ban marriage even between third-degree relatives (first cousins). The Talmud explicitly endorses negative eugenics when it forbids marriage for individuals coming from families with perceived hereditary defects (e.g. lepers and epileptics), and positive eugenics by encouraging marriages with members of scholarly families (a bit self-serving from the highly educated Talmudic authors, for sure!). Greeks (not just the notorious Spartans, see also Plato and Aristotle) and Romans routinely and swiftly got rid of their “undesirables”, as many other cultures did (and still do) less officially and openly. More close to home, the decrease in the incidence of certain genetic diseases in high-risk populations (e.g. thalassemia in Sardinia and Cyprus, Tay-Sachs disease among Ashkenazi Jews) through voluntary screening and genetic counseling has been one of the most significant success stories of medical genetics, and enjoys wide public support and participation in the affected communities.
Even more problematic for the claim that “Darwinism” was critical and instrumental in the development of eugenics is the uncomfortable fact that eugenics was also openly embraced by opponents of evolution (the first eugenics sterilization laws in the world were passed in 1907 Indiana, hardly a hotbed of “Darwinists”). The most notable of these anti-evolution eugenics supporters was probably William J. Tinkle, geneticist and prominent Creationist. Tinkle taught at religious LaVerne College and Taylor University, and participated in the activities of the Deluge Society, the first “Creation Science” organization. He then joined forces with the “young lions” of Creationism, Henry Morris, Duane Gish and Walter Lammerts, and with them he was one of the 10 Founding Fathers of the Creation Research Society, which later became the Institute for Creation Research.
Tinkle opposed evolution and Darwinian theory, but was an enthusiastic proponent of eugenics, and published several articles on the subject. In his 1939 textbook “Fundamentals of Zoology” he devotes a section to “The Need of Human Betterment”, where he laments the existence of “defective families” who “give birth to offspring like themselves” , producing “persons of low mentality, paupers and criminals in much greater ratio than the general population” [8, p. 130]. Negative eugenics via institutionalization seems to have been his preferred eugenic solution:
It is an excellent plan to keep defective people in institutions for here they are not permitted to marry and bear children.[8, p. 131]
[Scientists who are working at the task of improving the human race] would like to increase the birth rate of families having good heredity, while those people having poor heredity should not marry at all.[8, p. 131]
Figure 65 from Tinkle’s “Fundamentals of Zoology” illustrates the effect of differential reproduction on human population demographics. Pace the Discovery Institute propaganda, Tinkle did not need “Darwinism” or materialism to draw his eugenical conclusions.
Unsavory as they sound to us today, Tinkle’s writings in 1939 are probably within the mainstream of his time, and fall well short of those of Nazi apologists and proponents of extermination of “defectives” (such as conservative Catholic and Nobel Prize winner Alexis Carrel ). Like the majority of American eugenicists of the time, Tinkle seems to have thought that eugenics would humanely solve otherwise apparently intractable social problems and relieve human suffering (indeed, many progressive Christian clergymen and churches in America endorsed eugenics for precisely these reasons ).
Much more troubling, however, are Tinkle’s opinions of almost 30 years later, in his book “Heredity. A study in science and the Bible” published in 1967, while Tinkle was the Secretary of the Creation Research Society. In its chapter “The prospect for eugenics”, far from having abandoned his support for the practice, Tinkle sounds more radical about it. He writes positively about sterilization for the “feeble-minded” (carefully classified as “morons”, “imbeciles” and “idiots”) and people with other hereditary conditions. Sterilization in a male, he says “is a simple operation”, and “in a girl or woman, [it] is as serious as removal of the vermiform appendix” [11, p. 139]. While he admits that it is impractical to sterilize all “defectives”, he still thinks it’s worth a shot when possible:
At the present time there are in the United States more than a million people with serious hereditary defects, and to reduce their numbers by even a few thousand would reduce the amount of discomfort and hardship in the future. Unfortunate births are reduced by segregation also but there are not enough institutions to house nearly all the ones who have unfortunate genes. Institutional care is expensive but as compared to total government expenditure it is small.
Sterilization is sometimes employed with the consent of the patient for non-eugenic purposes. An example is a woman who has borne three children by Caesarean section and could not stand another birth. Persons who are on the borderline of normal mentality may be able to marry and care for themselves but would not be good parents. Their children might be normal or might be defective, and at any rate would have poor home discipline. Such persons sometimes are prevailed upon to submit to sterilization, to their own advantage. [11, pp140-141]
Tinkle was well aware of the dangers of eugenics, and mentions the horrors of Nazism (though he disturbingly feels it necessary to specifically note that among the millions of people killed by that regime “many [were] of the highest types”) and of forced sterilization (only however insofar as it was applied as a punishment for sex offenses and other forms of “misbehavior”, and thus “flout[ing] the law”). But those concerned with the “sanctity of human life” should not fear, because Tinkle was on top of it:
A careful reading of eugenic literature reveals that it may inculcate less respect for human life. In this way it runs counter to democracy, which stresses the worth and rights of the individual. The Bible teaches that life comes from God and that it is wrong to take that which one can not give. Unfortunately there are other programs also which destroy the idea of the sacredness of life. We refer to murder on the screen, war, and the teaching that man originated from, and still is, an animal. [emphasis mine]
We mention these unfortunate results [i.e. Nazism and “misapplied” sterilization] as dangers only; not as objections to attempting to improve our race by application of known genetics principles. [11, p.143]
Thus, on the eve of the Apollo moon landing, the Secretary of the preeminent Creationist organization in the US was denouncing the teaching of evolution as immoral, but thought sterilization on the “feeble-minded” was A-OK. I hope Dr. West & C will include this interesting case in their future discussions of how “Darwinism” was the origin and key motivation for eugenics, and materialism its philosophical basis.
So, the pill the ID advocates are trying to get the public to swallow is - surprise! - filled with over-simplified and dishonestly slanted propaganda: while the modern eugenic movement embraced and built on the ideas of Darwin and of evolutionary biology, among other disciplines, for its theoretical foundations, eugenics in itself is neither necessarily Darwinian nor inherently materialistic in nature, and its historical, social and philosophical roots reach far wider and deeper than the simple flow-chart Darwin -> Galton -> eugenics. The ID advocates’ misrepresentation and exploitation of this argument for their quixotic battles against evolutionary science is, once again, a disservice to the public.
—–  J. West, “Darwinism and Eugenics Revisited”, Evolution News and Views blog, 4/20/07  quoted in: M Bansal “Policy Expert Sees Darwinism-Eugenics Link”, CNSNews.com, 5/1/07  B Chapman, “John West and the Darwin-Eugenics Link”, Evolution News and Views blog, 5/1/07  M Egnor, “Eugenic Birthdays”, Evolution News and Views blog, 3/30/07  M Egnor, “Pseudo-Darwinism: Dr. Cartwright’s Error and Eugenics”, Evolution News and Views blog, 3/30/07  D. Klinghoffer, “Happy Darwin Day! Celebrating mankind’s discovery of eugenics.”, The Weekly Standard, 2/12/07. Incidentally, that sentence misrepresents Singer’s point, which in context refers not to divinely-derived, universal human rights and dignity (for which the Hebrew people objectively had little use), but to the Genesis-based justification of human “dominion” over other living creatures. The original is here.  for serious scholarly treatment of the subject, see Daniel J. Kevles, In the Name of Eugenics. Genetics and the Uses of Human Heredity, Alfred A Knopf Inc, 1985 and Harvard University Press, 1995; and Elof A Carlson The Unfit: A History of a Bad Idea, Cold Spring Harbor Laboratory Press, 2001. Another interesting read is John Waller’s article Ideas of Heredity, Reproduction and Eugenics in Britain, 1800-1875 (Stud. Hist. Phil. Biol. & Biomed. Sci. 32, 457–489, 2001), which describes the social and intellectual milieu in which Galton’s ideas were formed and flourished, and shows how in fact widespread eugenic sentiments and even explicit calls for eugenics-oriented social intervention predated not only Galton’s Hereditary Talent and Character, but also On the Origin of Species.  W. J. Tinkle Fundamentals of Zoology, Zondervan, 1939.  Andres H. Reggiani God’s Eugenicist: Alexis Carrel And the Sociobiology of Decline, Berghahn Books, 2006.  Christine Rosen, Preaching Eugenics: Religious Leaders and the American Eugenics Movement, Oxford University Press, 2004.  William J Tinkle Heredity: A Study in Science and the Bible, St. Thomas Press, 1967.