Summary In 1979, Robert C. Olby published an article titled ?Mendel no Mendelian??, in which he questioned commonly held views that Gregor Mendel (1822?1884) laid the foundations for modern genetics. According to Olby, and other historians of science who have since followed him, Mendel worked within the tradition of so-called hybridists, who were interested in the evolutionary role of hybrids rather than in laws of inheritance. We propose instead to view the hybridist tradition as an experimental programme characterized by a (...) dynamic development that inadvertently led to a focus on the inheritance of individual traits. Through a careful analysis of publications on hybridization by Carl Linnaeus (1707?1778), Joseph Gottlieb Koelreuter (1733?1806), Carl Friedrich Gärtner (1772?1850), and finally Mendel himself, we will show that this development consisted in repeated reclassifications of hybrids to accommodate anomalies, which in the end allowed Mendel to draw analogies between whole organisms, individual traits, and ?elements? contained in reproductive cells. Mendel's achievement was a product of normal science, and yet a revolutionary step forward. This also explains why, in 1900, when the report he gave on his experiments was ?rediscovered?, Mendel could be read as a ?Mendelian? (shrink)

There are several interpretations of the argument structure of Darwin's Origin of Species, representing Covering-Law, Inference-to-the-Best-Explanation, and (more recently) Semantic models. I argue that while all three types of interpretation enjoy some textual support, none succeeds in capturing the overall strategy of the Origin, consistent with Darwin's claim that it is 'one long argument'. I provide detailed criticisms of all three current models, and then offer an alternative interpretation based on the view that there are three main argument strategies in (...) the Origin, all supporting the 'causal efficacy' of Darwin's theory. This interpretation provides both a more unified treatment of the text, and some important implications concerning the relation between general philosophical models of scientific theory support and specific historical cases. (shrink)

Familiarity with Charles Darwin's treatise on evolution is essential to every well-educated individual. One of the most important books ever published--and a continuing source of controversy, a century and a half later--this classic of science is reproduced in a facsimile of the critically acclaimed first edition.

The publication of Darwin's On the Origin of Species in 1859 ignited a public storm he neither wanted nor enjoyed. Having offered his book as a contribution to science, Darwin discovered to his dismay that it was received as an affront by many scientists and as a sacrilege by clergy and Christian citizens. To answer the criticism that his theory was a theory only, and a wild one at that, he published two volumes in 1868 to demonstrate that evolution was (...) obvious to anyone who cared to look at a bull in a pasture or a dog on a hearth. In response to those who insisted that species were distinct since creation, Darwin pointed to breeders of pigs and pigeons. In reply to those who protested that human intervention is one thing and natural selection another, he argued, "If organic beings had not possessed an inherent tendency to vary, man could have done nothing." To counter those who scorned his descriptions of species in exotic places, he submitted local evidence of cabbages and cauliflower. Based on a wide array of sources, from ancient pictographs to Polish roosters, from skins and from skeletons, from scientific journals and breeding manuals, Darwin assembled a mass of proof--and a hypothesis about species reversion that risked his reputation anew. The Variation of Animals and Plants under Domestication is a two-volume compilation of his thorough and intensive research and the revolutionary conclusions that resulted. The first portion of his work is dedicated to a meticulous analysis of various aspects of plant and animal life, including an inventory of varieties and their physical and behavioral characteristics, investigation of the impact of a species' surrounding environment and the role that both natural and forced changes in this environment have had. Darwin then turns to a richly detailed discussion of the roles of inheritance and crossing in the development of species. A wealth of illustrations further support and enhance his findings. This fascinating, invaluable, and courageous undertaking eventually formed the foundation for our current understanding of evolution. "In science as in politics the victors tend to write the history books. As a result, the record of the past is edited, intentionally or unintentionally, so that it focuses mainly on the precursors of contemporary orthodoxy. Such a focus may accurately represent the genealogy of modern ideas, but it almost inevitably misrepresents the historical experience of their progenitors... Even the powerful, persuasive, and ultimately triumphant theory of evolution by natural selection required not only defense, but repeated buttressing and revision. Variation showed Darwin hard at work on this rearguard action, using the materials he had at hand... His information was gleaned from the observations of fanciers, breeders, and amateur naturalists, as well as from the treatises of those on the cutting edge of zoology and botany. As hindsight narrows the historical spotlight, it imposes its own sense of hierarchy on the preoccupations of the past. But Darwin was interested in all of these topics, valued all of these sources, and belonged, to a greater or lesser extent, to all of these communities."--from the Introduction. (shrink)

The central role played by Darwin's analogy between selection under domestication and that under nature has been adequately appreciated, but I have indicated how important the domesticated organisms also were to other elements of Darwin's theory of evolution-his recognition of “the constant principle of change,” for instance, of the imperfection of adaptation, and of the extent of variation in nature. The further development of his theory and its presentation to the public likewise hinged on frequent reference to domesticates.We have seen (...) that Darwin's reliance on the analogy between domesticated varieties and wild species was a bold and original step, in light of contemporary views on the nature of domesticates. However, as Darwin undoubtedly foresaw, his reliance on the analogy created difficulties as well as solving problems, and these began with his Malthusian codiscoverer of the principle of natural selection, Alfred Russel Wallace. Wallace's paper “On the Tendency of Varieties to Depart Indefinitely from the Original Type,” presented to the Linnean Scoiety along with the first public unveiling of Darwin's theory, states: We see, then, that no inferences as to varieties in a state of nature can be deduced from the observation of those occurring among domestic animals. The two are so much opposed to each other in every circumstance of their existence, that what applies to the one is almost sure not to apply to the other. Domestic animals are abnormal, irregular, artificial; they are subject to varieties which never occur and never can occur in a state of nature.62Much has been made of the similarity of views of Darwin and Wallace, but this quotation surely reveals how utterly different their views were on what to Darwin was an important matter. Several critics of the Origin saw Darwin's reliance on the domesticates as his Achilles heel. As Young has pointed out, Samuel Wilberforce included the following passage in his attack on the Origin: Nor must we pass over unnoticed the transference of the argument from the domesticated to the untamed animals. Assuming that man as the selector can do much in a limited time, Mr. Darwin argues that Nature, a more powerful, a more continuous power, working over vastly extended ranges of time, can do more. But why should Nature, so uniform and persistent in all her operations, tend in this instance to change? Why should she become a selector of varieties?63Another critic, Fleeming Jenkin, found the analogy a weakness in Darwin's theory because of the limited extent of variation in any one direction in domestic animals and plants.64 We have already seen that Darwin had confided a similar view to his notebook thirty years earlier, but changed his mind as a result of his profound study of domesticates. De Beer's reference to “an English country gentleman's knowledge of domestic plants and animals and their breeding”65 fails totally to recognize the originality and depth of Darwin's knowledge of domesticates.Why did Darwin, against the currents of his time, rely so heavily on mankind's experience with domesticated organisms to shape his theory about species in nature? On reason is that only with domesticates was an approach that came close to experimental verification possible. Darwin fully realized the inadequacies of the experiment, as is emphasized by his repeated contrasting of selection under nature and selection by man. Yet the extensive experience and data of plant and animal breeders offered the only reliable base against which Darwin could continually challenge his views. As he wrote in the introduction to Variation, with domestication, “man ... may be said to have been trying an experiment on a gigantic scale.”66 Given Darwin's high opinion of the quantitative work of Malthus and Quetelet (as emphasized by Schweber),67 and his unremitting efforts to secure data by which to test his theories, it was inevitable that he should attach high significance to domesticated varieties. John Tyndall, in his Belfast address of 1874, said: “The strength of the doctrine of Evolution consists, not in experimental demonstration (for the subject is hardly accessible to this mode of proof), but in its general harmony with scientific thought.”68 Darwin would have agreed with the latter thought, but I think he would have challenged the preceding one on the grounds that long experience with domesticated varieties did provide an element of experimental demonstration. It gave him confidence in his theory, and he used his vast knowledge of artificial selection boldly and creatively. (shrink)

Early nineteenth-century natural history books reveal that British naturalists depended heavily on correspondence as a means for gathering information and specimens. Edward Newman commented in hisHistory of British Ferns: ‘Were I to make out a list ofallthe correspondents who have assisted me it would be wearisome from its length.’ Works such as William Withering'sBotanical Arrangementshow that artisans numbered among his correspondents. However, the literary products of scientific practice reveal little of the workings or such correspondences and how or why they (...) were sustained. An exchange or letters is maintained if the interests of both recipient and writer are satisfied. Withering's book tells us only that his interests were served by his correspondents; it allows us to say nothing with certainty about the interests of those who wrote to him. Published texts effectively hide the means by which the author determined the veracity of distant correspondents and also the way these informants demonstrated their credibility. (shrink)

In Darwinism's Struggle for Survival Jean Gayon offers a philosophical interpretation of the history of theoretical Darwinism. He begins by examining the different forms taken by the hypothesis of natural selection in the nineteenth century and the major difficulties which it encountered, particularly with regard to its compatibility with the theory of heredity. He then shows how these difficulties were overcome during the seventy years which followed the publication of Darwin's Origin of Species, and he concludes by analysing the major (...) features of the genetic theory of natural selection, as it developed from 1920 to 1960. This rich and wide-ranging study will appeal to philosophers and historians of science and to evolutionary biologists. (shrink)

The naturalist and geologist Charles Darwin ranks as one of the most influential scientific thinkers of all time. In the nineteenth century his ideas about the history and diversity of life - including the evolutionary origin of humankind - contributed to major changes in the sciences, philosophy, social thought and religious belief. This volume provides the reader with clear, lively and balanced introductions to the most recent scholarship on Darwin and his intellectual legacies. A distinguished team of contributors examines Darwin's (...) main scientific ideas and their development; Darwin's science in the context of its times; the influence of Darwinian thought in recent philosophical, social and religious debate; and the importance of Darwinian thought for the future of naturalist philosophy. New readers will find this a most convenient and accessible guide to Darwin. Advanced students and specialists will find a conspectus of recent developments in the interpretation of Darwin. (shrink)

Although Henry Drummond's Natural Law in the Spiritual World is frequently cited by historians in relation to the impact of evolutionary theories on the Victorian churches, attention has not been paid to the audiences of working-class men in Glasgow for whom the papers were originally constructed. By drawing upon the notebook in which the author sketched out the series of addresses, in addition to materials relating to the interpretative habits of these audiences; I am able to consider the text as (...) a work of practical apologetics rather than as a contribution to elite intellectual debate. This paper promises to open up new lines of enquiry with regard to the materials with which working-class audiences attempted to construct their own interpretations of contemporary scientific and religious issues. It also highlights Drummond's hitherto unrecognized use of specific practices of biblical exegesis and his debt to the work of the anatomist Richard Owen which, by keeping different forms of life distinct, and explaining organization as the effect of life already present, allowed the author to visualize the process of descent in terms of an inherent tendency to change in line with the unfolding of a pre-existing plan. (shrink)

While Wallace disagreed with Darwin that domesticates provided a great deal of useful information on wild populations,71 Darwin continued to draw on his domesticated animals and plants to inform him on the workings of his theory. Unlike Wallace, his exposure to natural populations was extremely limited after his return from the Beagle voyage. By the 1850s, he had settled into a life at Down House and was becoming more and more withdrawn from London scientific circles. He turned to his network (...) of informants, visits from colleagues such as Hooker and T. H. Huxley, subscriptions to various journals, and his own experimental studies at Down.This work on domesticates was clearly related to other natural history studies conducted by Darwin and others during the same period. For example, during the 1850s when Darwin worked on domesticates, he was also engaged in questions of geographic distribution. To study the dispersal and subsequent viability of introduced seeds, he soaked various seeds in a tub filled with seawater and counted which of the seeds floated after a given period; later he planted the seeds in the yard at Down to look for potential viability. There was no attempt at controlled, replicated experiments in these studies, or in his work with domesticates, nor should there have been. To Darwin the results of one experiment represented a potential truth of nature, and he was quick to seize upon these results as supporting evidence for his theory.I have suggested in this paper that his work on domesticates was not simply meant to provide an analogy for natural selection but rather became a research program to investigate other aspects of his natural selection theory, especially inheritance and variability; these subjects were integral parts of his theory of natural selection, but by 1859 he had not found a mechanism to account for them. The experiments brought home the difficult problems of inheritance, and Darwin specifically formulated pangenesis to account for these problems. Pangenesis was not an afterthought but an integration of several decades of thinking on inheritance. It was a unified theory to explain the complicated results he witnessed in his own experiments.Much of the Darwin scholarship has focused on Darwin's path toward the discovery of natural selection. Natural selection per se was a major interest, but not the only area of interest to Darwin. Inheritance was an area of serious concern for him both before and after he had formulated natural selection. His experimentation with domesticates was an attempt to look beyond natural selection and to concentrate on the difficult subject of inheritance. He found inheritance especially troublesome, requiring a “provisional hypothesis” to account for it. To see domesticates, as they are described in the Origin, as merely an analogy for natural selection, does not account for the importance Darwin placed on them. For him they were not man's monstrous productions, but worthy experimental subjects providing him with crucial information on inheritance. (shrink)

Summary In The Origin of Species, Charles Darwin famously accounted for the lack of fossil evidence in support of species evolution on the grounds that the fossil record is naturally incomplete. This essay examines a similar argument that Darwin applied to his analogy between natural and artificial selection: the scarcity of data about the historical backgrounds of domestic breeds was the natural by-product of an extremely gradual change process. The point was to enhance the ability of the artificial selection analogy (...) to suggest that nature's species had undergone a similar transformation. Darwin did not depend on this negative inference alone, however, for in his writings he included whatever information he could find about the actual histories of particular breeds. A comparison with Darwin's treatment of the fossil record suggests the reasonableness of this combined use of opposite kinds of evidence to establish a single point. The comparison also suggests the unique qualities of negative inference as applied to the breeding analogy. (shrink)

In Darwinism's Struggle for Survival Jean Gayon offers a philosophical interpretation of the history of theoretical Darwinism. He begins by examining the different forms taken by the hypothesis of natural selection in the nineteenth century and the major difficulties which it encountered, particularly with regard to its compatibility with the theory of heredity. He then shows how these difficulties were overcome during the seventy years which followed the publication of Darwin's Origin of Species, and he concludes by analysing the major (...) features of the genetic theory of natural selection, as it developed from 1920 to 1960. This rich and wide-ranging study will appeal to philosophers and historians of science and to evolutionary biologists. (shrink)