The historical context of natural selection: The case of Patrick Matthew

Conclusions It should be evident from the foregoing discussion that one man's natural selection is not necessarily the same as another man's. Why should this be so? How can two theories, which both Matthew and Darwin believed to be nearly identical, be so dissimilar? Apparently, neither Matthew nor Darwin understood the other's theory. Each man's viewpoint was colored by his own intellectual background and philosophical assumptions, and each read these into the other's ideas. The words sounded the same, so they assumed the concepts must als be the same.¹²³ As Ghiselin has pointed out, historians attempting to evaluate Darwin's predecessors have been similarly blinded by a preoccupation with words, without regard to their proper context.¹²⁴ In the case of Matthew, the practice of quoting only brief passages from the appendix to Naval Timber and Arboriculture, without relating them to the rest of his work, has suggested a greater resemblance to Darwin's theory than actually exists.It is clear, both from the use which Matthew made of his ideas and from the philosophical roots of his natural world view, that he could not have arrived at the concept of natural selection by the same thought process which Darwin employed. His discussion of natural selection is presented not as an argument, but as an axiom. No theory is proposed, no evidence marshaled to support it. Natural selection is stated as a fact, a Law of Nature, unquestioned, and presumably, unquestionable.Despite his clamor for recognition as the discoverer of natural selection, Matthew recognized and acknowledged this very fundamental difference between Darwin and himself. In a letter to the Gardener's Chronicle of May 12, 1860, he wrote:To me the conception of this law of Nature came intuitively as a self-evident fact, almost without an effort of concentrated thought. Mr. Darwin here seems to have more merit in the discovery than I have had—to me it did not appear a discovery. He seems to have worked it out by inductive reason, slowly and with due caution to have made his way synthetically from fact to fact onwards; while with me it was by a general glance at the scheme of Nature that I estimated this select production of species as an a priori recognisable fact—an axiom, requiring only to be pointed out to be admitted by unprejudiced minds of sufficient grasp.¹²⁵ In the same letter, Matthew maintained that his ideas had not been accepted because the age was not ripe for such ideas.¹²⁶ Nor, he said, was the present age. He considered the inability of most of Darwin's critics to grasp his theory to be incurable. Yet he did not argue that natural selection should be accepted because of the evidence, but rather, that it should be accepted on faith:Belief here requires a certain grasp of mind. No direct proof of phenomena embracing so long a period of time is within the compass of short-lived man. To attempt to satisfy a school of ultra skeptics, who have a wonderfully limited power of perception of means to ends... would be labour in vain.... They could not be brought to conceive the purpose of a handsaw though they saw its action, if the whole individual building it assisted to construct were not presented complete before their eyes... Like a child looking upon the motion of a wheel in an engine they would only perceive and admire... without noticing its agency in... affecting the purposed end.¹²⁷ Here, then, is the final irony. In a passage urging acceptance of Darwin's theory, a theory which was to banish design and purpose from the natural world, we find echoes of Paley and of Providence.Loren Eiseley has lamented the fact that Matthew did not bring his views into the open, because the amount of ground he was able to cover in a few paragraphs suggests that he might have been able to sustain a longer treatise.¹²⁸ Now that the intellectual and historical context of Matthew's ideas are known, this statement is no longer tenable. Matthew was not a scientist, and his books were not written as biological treatises. His discussions of natural selection were not attempts to cover ground in advancing a particular scientific theory, but were simply reflections of his own assumptions about the natural world.Furthermore, despite Matthew's acceptance of evolution and natural selection, his biological thought was basically conservative on points where Darwin's was radical. Where Matthew saw a series of stable worlds interrupted by violent upheavals, Darwin saw a continuous process of change in an ever-fluctuating world. Where Matthew conceived of species in terms of Aristotelian classes and essences, Darwin revolutionized our concept of species by treating them as populations. Where Matthew saw a world of design and beauty functioning according to natural laws laid down by benevolent Providence, Darwin abolished design and Providence from nature and ushered in a world which cycles ever onward according to laws of chance and probability.It is not even particularly useful to point to Matthew as evidence that evolution was in the air prior to 1859.¹²⁹ His ideas did not represent the first wave of a coming revolution, but were the product of his own personal philosophical outlook, as expressed in the context of the biological thought of the 1830's. Matthew is important in the history of ideas, not simply because he accepted the concept of evolution or thought of something resembling natural selection, but because he did so without overthrowing, in his own mind, any of the basic philosophical assumptions which had underlain biological science since Aristotle. In recognizing Matthew's failure to do so, we are in a position to appreciate more fully the significance of the Darwinian Revolution.     

Darwin's use of the analogy between artificial and natural selection

Conclusion 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.⁶² Much 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?⁶³ Another 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 breeding⁶⁵ 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.     

God and natural selection: The Darwinian idea of design

Conclusion If we arrange in chronological order the various statements Darwin made about God, creation, design, plan, law, and so forth, that I have discussed, there emerges a picture of a consistent development in Darwin's religious views from the orthodoxy of his youth to the agnosticism of his later years. Numerous sources attest that at the beginning of the Beagle voyage Darwin was more or less orthodox in religion and science alike.⁷⁸ After he became a transmutationist early in 1837, he concluded that the doctrine of secondary causes must be extented even to the history of life and that after the first forms of life were created, there was no further need for divine intervention, except where man was concerned. Man's body, he thought, was produced by the process of transmutation, but he believed for a time that man's soul was superadded. By mid-1838 he had become convinced that nothing, after the creation of life, was due to miracles. God works only through laws, which are capable of producing every effect of evey kind which surrounds us. The existence of man, the idea of God in man's mind, and the harmony of the whole system were in his eyes prearranged goals of deterministic laws imposed by God. Such a conception excludes the miracles on which Christianity depends; but it is not possible to say whether Darwin's loss of Christian faith, which occurred at about this same time, preceded and made possible his materialism or was rather caused or hastened by it.⁷⁹ In the weeks after his reading of Malthus, Darwin's belief in a plan of creation gave way to the belief that God created matter and life and designed their laws, leaving the details, however, to the workings of chance. This remained his view until the 1860s.There is no exact parallel between this development of Darwin's religious views and the development of his ideas on evolution, but there is a general correspondence. When he believed in a plan of creation, Darwin's theory of transmutation did not depend on struggle or the selection of chance variations. Adaptation was, for him, an automatic response to environmental chance. From late 1838 to 1859 he believed in designed laws and chance, and this belief, too, has its parallel in his theory. The element of chance in natural selection meant that there could be no detailed plan,in which even man's idea of God would be a necessary outcome of nature's laws (man himself is not a necessary outcome of the working of natural selection).⁸⁰ But Darwin still believed nature was programmed to achieve certain general ends. We might say that he believed in a general, though not a special, teleology. Natural selection was for him a law to maximize utility, creating useful organs, retaining vestiges for future use. For many years it was a law designed to produce organisms perfectly adapted to their environments. Only later did Darwin come to doubt even this sort of design in nature.⁸¹ One way of describing the development of Darwin's evolutionary thought is to say that it shows a gradual abandoning of his theistic assumptions, so that by the late 1860s his theory was informed to a slighter extent by notions of purpose and design than it was in 1838 or 1844 or 1859.     

Studies of animal populations from Lamarck to Darwin

Summary and conclusions Darwin's theory of evolution brought to an end the static view of nature. It was no longer possible to think of species as immortal, with secure places in nature. Fluctuation of population could no longer be thought of as occurring within definite limits which had been set at the time of creation. Nor was it any longer possible to generalize from the differential reproductive potentials, or from a few cases of mutualism between species, that everything in nature was fitted to produce general ends, and reciprocal uses. ¹³⁴ The appeal to design could no longer be substituted for answers to questions concerning animal demography. Instead, the dynamics of a population had to be viewed as the outcome of species' struggle against animate and inanimate factors in the environment. Both the members of a species and the environmental factors tend to vary randomly, and therefore neither evolution nor population dynamics could be fully understood alone. For this reason Darwin's linking of the two subjects was inevitable and not merely an historical accident. Since Darwin had shown that no automatic equilibrium existed, he demonstrated the importance of closer study of the causes of population dynamics and extinction. He also indicated that an understanding of population depends upon the development of a broad knowledge in ecology.Viewed from another direction, Darwin's work ended the early modern era of population studies by clarifying three interrelated problems which were important for understanding population: extinction, distribution, and the nature of species. The components of his answer had been discussed in the eighteenth century, but there had not existed enough evidence for the completion of the revolution in thought which had then begun. At the beginning of the nineteenth century, Playfair found the evidence for extinction conclusive, and, in spite of Lamarck, Curvier convinced the scientific world that there could no longer be any doubt about it. This was a step the importance of which, with his limited knowledge of biogeography and population, Cuvier could not have fully realized. Lamarck attempted, with his evolutionary theory, to circumvent the necessity for admitting extinction, but he overestimated the adaptability of organisms and in doing so he underestimated the importance of competition and the whole field of ecology. On the other hand, he was not willing to let questions such as the origin of species remain taboo to science. The origin of species was a biogeographical as well as a paleontological question. Humboldt correlated environment with the distribution of species and conveyed the impression that plant communities are subject to change. De Candolle, following the lead of Linnaeus and Humboldt, emphasized the ecological aspects of biogeography, not only the importance of habitat and range, clearly showing the ecological effects of competition. The entomologists Kirby and Spence took a faltering step toward understanding the relationship between population and ecological role, but they fell short of any significant new conclusions. Neither they nor Swainson could fully comprehend the new perspective of De Candolle.Lyell was able to bring together the evidence from these three lines of investigation and weave them into an important synthesis that almost accomplished that Darwin later did. Although opposing Lamarck's theory of evolution, Lyell had a dynamic view of ecology. He realized that population dynamics offered an important key to the understanding of biogeography. Since he knew that species become extinct, he investigated closely the factors which could either preserve or extinguish species. While explaining these factors, he described the interrelationships of species in greater detail than had ever been done before. Forbes continued to develop Lyell's ecological concepts, and his first-hand field experience enabled him to describe biotic communities more concretely than Lyell had.Having the advantages of Lyell's understanding and his own experience from a global voyage, Darwin could take the final step from the static to the dynamic concept of life. He had seen populations fluctuating and also fossil species in South America, and on the Galapagos Islands he had encountered a biogeographical problem that could not be credibly solved without the idea of evolution. However, the bare idea of evolution did not fully answer his questions. He sought physiological causes of extinction before he read Malthus and realized that De Candolle and Lyell had correctly emphasized the importance of competition. Darwin found that, in order to understand evolution, he needed to improve his understanding of ecology. He wanted to know when populations were most easily decimated, how extensive were competition and cooperation, what effects parasites have upon populations, and what changes occur in biotic communities when a species is either added or subtracted. He contributed to some extent to answering these questions. Though there remained much for others to do, there was now a new and more secure theoretical framework within which later studies could be interpreted. As Ernst Mayr has observed, Darwin's consistent thinking in terms of population has had an impact on biological theory and practice which is second only to his sponsorship of natural selection as the mechanism of evolution. ¹³⁵     

Darwin,Wallace, and Huxley,and Vestiges of the Natural History of Creation

Conclusion Publication of the Vestiges and the rather primitive theory of evolution it expounded thus played a significant role in the careers of Darwin and Wallace. In addition, in spite of his poor opinion of the Vestiges, it presented Huxley with a convenient topic for critical discussion and the opportunity to focus more attention on the subject of evolution. The dynamic interactions among these leading figures of nineteenth-century natural science helped spur the development of more sophisticated models of evolution.Darwin had a proper appreciation of Chambers's contribution to evolutionary thought, although he fully recognized the shortcomings of this work. He understood the importance of allowing fresh ideas about organic change to be ventilated. However, he was primarily concerned with his own theory and viewed all developments in evolutionary biology from this perspective. If he did not give full consideration to Chambers and his book early on, it was due mainly to his feeling that the concepts in the Vestiges were very different from his own; he was therefore reluctant to embrace them as the forerunners of his own theory. As a scholar, he was also troubled by the scientific errors in the book. However, the record demonstrates that he attempted to make amends for any oversight on his part. His generous letter to Chambers's daughter, and his gracious treatment of Chambers during the brief time the latter lived in London, are ample proof of that.The attacks of Huxley, Sedgwick, and other prominent natural historians and geologists at the time, the problems inherent in Chambers's evolutionary theory, and the publication of the Origin, are the major reasons why the Vestiges became a neglected work. Nevertheless, Chambers's contribution will always stand out because, together with those of other late eighteenth- and early nineteenth-century predecessors of Darwin, it laid the foundations of modern evolutionary thought and, more importantly, helped prepare the scientific community for the more fully developed ideas of Darwin and Wallace.     

Darwin’s two theories, 1844 and 1859

Darwin’s first two, relatively complete, explicit articulations of his theorizing on evolution were his Essay of 1844 and On the Origin of Species published in 1859. A comparative analysis concludes that they espoused radically different theories despite exhibiting a continuity of strategy, much common structure and the same key idea. Both were theories of evolution by means of natural selection. In 1844, organic adaptation was confined to occasional intervals initiated and controlled by de-stabilization events. The modified descendants rebalanced the particular “plant and animal forms … unsettled by some alteration in their circumstances.” But by 1859, organic adaptation occurred continuously, potentially modifying the descendants of all organisms. Even natural selection, the persistent core of Darwin’s theorizing, does not prove to be a significant basis for theory similarity. Consequently, Darwin’s Origin theory cannot reasonably be considered as a mature version of the Essay. It is not a modification based on adjustments, further justifications and the integration of a Principle of Divergence. The Origin announced a new “scientific paradigm” while the Essay did little more than seemingly misconfigure the operation of a novel mechanism to extend varieties beyond their accepted bounds, and into the realm of possible new species. Two other collections of Darwin’s theorizing are briefly considered: his extensive notes of the late 1830s and his contributions to the famous meeting of 1 July 1858. For very different reasons, neither constitutes a challenge to the basis for this comparative study. It is concluded that, in addition to the much-debated social pressures, an unacknowledged further reason why Darwin did not publish his theorizing until 1859, could have been down to his perceptive technical judgement: wisely, he held back from rushing to publish demonstrably flawed theorizing.     

Charles Lyell's Antiquity of Man and its critics

Conclusion: Toward a reassessment It should be clear that Lyell's scientific contemporaries would hardly have agreed with Robert Munro's remark that Antiquity of Man created a full-fledged discipline. Only later historians have judged the work a synthesis; those closer to the discoveries and events saw it as a compilation — perhaps a capital compilation,⁹⁵ but a compilation none the less. Its heterogeneity made it difficult to judge as a unity, and most reviewers, like Forbes, concentrated on the first part of Lyell's trilogy. The chapters on glaciation were admired by Lyell's friends but had relatively little appeal to more general readers. His discussion of the species question hedged far too much to please those who accepted the cogency of Darwin's evidence and arguments. This last section of the book blatantly lacks originality or commitment and certainly has no claim to classical status in anthropology.We are left, then, with the first twelve chapters, for it was this portion that dictated the book's title and that amassed the available evidence favoring the antiquity of the human species. Did it do anything more than marshall the evidence that others had discovered? I think not. Lyell could write with style and verve. Principles of Geology is a remarkably readable book. But Antiquity is the work of a geologist, not of a systematic student of man. Despite its occasional touches of power, it never captures the freshness and immediacy of Lubbock's Pre-historic Times nor the theoretical brilliance of E. B. Tylor's Researches into the Early History of Mankind (1865).⁹⁶ Antiquity utilizes little of the comparative method whereby Lyell's contemporaries used data from modern savagery to elaborate the possible social functions of the prehistoric remains being uncovered. It contains little social theory and has virtually no integrated framework. Even the first twelve chapters do not really hang together. As Hooker, commenting to Darwin on Lubbock's review, sadly wrote: Lubbock in [the] N[atural] H[istory] Review, had in a note called attention to Lyell's ... doing injustice to Prestwich & Falconer. I modified this expression injustice in Lubbock's paper (which was friendly and apologetic). I am deeply sorry for it, but what can one do? I do think Lyell's first XII chapters a complete mess.⁹⁷ In another letter to Darwin, Hooker described this first portion of Antiquity as confused and confusing.⁹⁸ Part of the problem, of course, lay in the subject's novelty for Lyell and for most of his contemporaries. At a deeper level, however, I believe that the book accurately reflects Lyell's uncertainties about Darwin's work and its implications for man.⁹⁹ Leonard Wilson's edition of Lyell's Scientific Journals provides a unique insight into Lyell's mind during the years just before he began to write Antiquity.¹⁰⁰ Preoccupied with the human implications of evolutionary biology, Lyell was not clear how many of those implications were compatible with his deep convictions about the dignity of man's place in the cosmos. With a certain naiveté, Lyell complained in 1873 that many of his readers had failed to see the natural connections among the three portions of Antiquity.¹⁰¹ Connections could indeed be drawn between man's antiquity and his evolutionary origins; Lyell's private Scientific Journals movingly demonstrate that he was well aware of this fact. But he never fully made the connections in his published writings. Antiquity of Man is more appropriately seen as the last gasp of the heroic period in British geology than as the opening salvo in a new, post-Darwinian anthropological synthesis. Between the founding of the Geological Society of London in 1807 and the middle of the nineteenth century, geology was recognized as one of the most exciting and innovative scientific fields in Britain.¹⁰² Lyell himself had contributed much to that drama, and by the 1860's he was a public figure of venerable proportions. More then any other man he represented a geology that had extended the boundaries of process, time, and life. The fundamental achievements of Lyell and his colleagues had been assimilated into the wider Victorian consciousness, yet the earlier public debates about genesis and geology had left untouched in its essentials the concept of Man as a moral, responsible, created being.¹⁰³ Lyell never abandoned this view of his own species, and in 1863 it was a completely responsible creature which, under the weight of empirical evidence, Lyell admitted had lived on earth far longer than had previously been thought. Certainly this more generous allowance for human existence was constitutive to what Burrow calls the evolutionary social theory of midcentury Britain.¹⁰⁴ Unlike Lyell, the younger representatives of this anthropology quietly accepted both man's antiquity and his aboriginal animality. Herbert Spencer's Principles of Psychology (1855), as well as the other volumes of his grand Synthetic Philosophy, presented as part of the cosmic process the development of human from prehuman beings.¹⁰⁵ Tylor's discussion of what in his Researches (1865) he called the gesture-language presupposed the gradual and de novo origin of language in early human populations.¹⁰⁶ Lubbock's young and polished mind was untroubled by the human implications of Darwin's work, and he cast his Prehistoric Times into such a perfect mold that it and its companionpiece (On the Origin of Civilization, 1870) went through seven editions each between 1865 and World War I, with their original theoretical structures intact. In a way that Lyell could not grasp, Lubbock was intrigued by questions concerning the origins of moral and religious beliefs and did not flinch at the thought of an amoral, atheistic creature as an ancestor.¹⁰⁷ Indeed, as the German naturalist Carl Vogt pointed out in his Lectures on Man, translated into English the year after Antiquity, both Darwin's theories and the primitive flint knives of the Stone Age bore witness to a time beyond that imaginable from the condition of the lowest present-day savage:From such a low condition [little better than anthropomorphous apes], compared to which that of the so-called savages of the old and new world is a refined civilisation, has the human species gradually extricated itself, in a bitter struggle for existence, which it was well able to maintain, by being gifted with a larger amount of brain and intelligence than that possessed by the surrounding animal world.¹⁰⁸ The easy integration of biological and social themes was perhaps the distinguishing hallmark of Victorian anthropology of the 1850's and 1860's. After his fashion, Lyell got both themes into Antiquity, but he carefully separated them with a seven-chapter wall of glacial ice. Lyell's anthropology was not that of a thoroughgoing evolutionist like Lubbock, Tylor, or Spencer. For Lyell prehistoric man was not a product of biological evolution. Rude and superstitious he may have been, but he possessed ritual and a belief in a future state, and thus deserved the epithet of noble, which Dryden gave to what he seems to have pictured to himself as the primitive condition of our race: as Nature first made man/when wild in woods the noble savage ran.¹⁰⁹ As a systematic argument, Lyell's book was at best a significant failure. As a popularization, it was a success — largely because of the personal stature of its author and the particular moment of its appearance. It helped establish the fact of man's antiquity with a wider Victorian audience, in itself no mean achievement. But Lyell was unable to exploit the fuller implications of his material in the service of a secular science of man. Ironically, he exploited only his colleagues' discoveries. Though the aging Lyell, with failing eyesight but unfailing mental powers, can still be seen as a man of considerable importance, his Antiquity belongs to the carefully circumscribed world of British geology rather than to the less disciplined world of Victorian anthropology.     

Experimenting with Transmutation: Darwin, the Beagle, and Evolution

Detailed analysis of Darwin’s scientific notes and other writings from the Beagle voyage reveals a focus on endemism and replacement of allied taxa in time and in space that began early in the journey. Though it is impossible to determine exactly when Darwin became a transmutationist, the evidence suggests that he was conversant with the transmutational ideas of Lamarck and others and testing (“experimenting” with) them—before he received a copy of Lyell’s Principles of Geology, vol. 2, in November 1832, in which Lyell describes and disputes Lamarck’s theory. To the two rhea species of Patagonia and the four mockingbird species of the Galapagos, we can now add the living Patagonian cavy (rodent) species, and its extinct putatively related species that Darwin collected at Monte Hermoso (Bahia Blanca) in the Fall of 1832, as a replacement pattern absolutely critical to the development of Darwin’s transmutational thinking. Darwin developed his first transmutational theory by adopting “Brocchi’s analogy” (Rudwick 2008)—i.e. that births and deaths of species are analogous to the births and deaths of individuals. Births and deaths of species, as of individuals, are thus explicable in terms of natural causes. Darwin explored these themes and the replacement of the extinct cavy by the modern species explicitly in his February 1835 essay (Darwin 1835a).

Trigonia and the origin of species

Conclusion While the Trigonia story is a microcosmic representation of nineteenth-century evolutionary debates, it also serves as a model for assessing the impact of new empirical material upon a controversial issue potentially explained by several internally consistent but contradictory theories; for there can be no fact quite so pristine as a discovery anticipated by no one. The reaction to modern trigonians was, I suspect, completely typical; all parties to the dispute managed to incorporate the new datum into their systems. Evolutionists emphasized the morphological differences between Mesozoic and modern forms and assumed that the disjunct distribution was an artifact of an imperfect record. Agassiz cited the known distribution in support of special creation, but announced that the discovery of a Tertiary species would discredit none of his ideas. Parkinson could not readily encompass the difference without evident improvement in his progressionist synthesis, but invoked almighty wisdom in his ignorance.I do not doublt that all these naturalists proceeded properly in refusing to yield to the anomalies of a single fact which destroyed no deductive sequence in any of their theories. When one considers the stupendous amount of misinformation current in early nineteenth-century scientific circles,⁴⁹ it is easy to appreciate the salutary aspects of stubbornness in the face of inevitable contradictory citations.De Beer⁵⁰ has marveled at Darwin's ability, in the 1844 sketch, to work his way through a mire of misinformation: It is a matter for wonder that with the meagre materials at his disposal he was able to steer a straight course across a largely uncharted ocean of ignorance, with rocks of falsehood right across his path. Yet Darwin approached these rocks with the idea of natural selection already firmly in mind. Any pure empiricist would have surrendered to confusion long before 1859.     

Historical Development of Origins Research

Following the publication of the Origin of Species in 1859, many naturalists adopted the idea that living organisms were the historical outcome of gradual transformation of lifeless matter. These views soon merged with the developments of biochemistry and cell biology and led to proposals in which the origin of protoplasm was equated with the origin of life. The heterotrophic origin of life proposed by Oparin and Haldane in the 1920s was part of this tradition, which Oparin enriched by transforming the discussion of the emergence of the first cells into a workable multidisciplinary research program.On the other hand, the scientific trend toward understanding biological phenomena at the molecular level led authors like Troland, Muller, and others to propose that single molecules or viruses represented primordial living systems. The contrast between these opposing views on the origin of life represents not only contrasting views of the nature of life itself, but also major ideological discussions that reached a surprising intensity in the years following Stanley Miller’s seminal result which showed the ease with which organic compounds of biochemical significance could be synthesized under putative primitive conditions. In fact, during the years following the Miller experiment, attempts to understand the origin of life were strongly influenced by research on DNA replication and protein biosynthesis, and, in socio-political terms, by the atmosphere created by Cold War tensions.The catalytic versatility of RNA molecules clearly merits a critical reappraisal of Muller’s viewpoint. However, the discovery of ribozymes does not imply that autocatalytic nucleic acid molecules ready to be used as primordial genes were floating in the primitive oceans, or that the RNA world emerged completely assembled from simple precursors present in the prebiotic soup. The evidence supporting the presence of a wide range of organic molecules on the primitive Earth, including membrane-forming compounds, suggests that the evolution of membrane-bounded molecular systems preceded cellular life on our planet, and that life is the evolutionary outcome of a process, not of a single, fortuitous event.It is generally assumed that early philosophers and naturalists appealed to spontaneous generation to explain the origin of life, but in fact, the possibility of life emerging directly from nonliving matter was seen at first as a nonsexual reproductive mechanism. This changed with the transformist views developed by Erasmus Darwin, Georges Louis Leclerc de Buffon, and, most importantly, by Jean-Baptiste de Lamarck, all of whom invoked spontaneous generation as the mechanism that led to the emergence of life, and not just its reproduction. “Nature, by means of of heat, light, electricity and moisture”, wrote Lamarck in 1809, “forms direct or spontaneous generation at that extremity of each kingdom of living bodies, where the simplest of these bodies are found”.Like his predecessors, Charles Darwin surmised that plants and animals arose naturally from some primordial nonliving matter. As early as 1837 he wrote in his Second Notebook that “the intimate relation of Life with laws of chemical combination, & the universality of latter render spontaneous generation not improbable.” However, Darwin included few statements about the origin of life in his books. He avoided the issue in the Origin of Species, in which he only wrote “… I should infer from analogy that probably all organic beings which have ever lived on this Earth have descended from some one primordial form, into which life was first breathed” (Peretó et al. 2009).Darwin added few remarks on the origin of life his book, and his reluctance surprised many of his friends and followers. In his monograph on the radiolaria, Haeckel wrote “The chief defect of the Darwinian theory is that it throws no light on the origin of the primitive organism—probably a simple cell—from which all the others have descended. When Darwin assumes a special creative act for this first species, he is not consistent, and, I think, not quite sincere …” (Haeckel 1862).Twelve years after the first publication of the Origin of Species, Darwin wrote the now famous letter to his friend Hooker in which the idea of a “warm little pond” was included. Mailed on February 1st, 1871, it stated that “It is often said that all the conditions for the first production of a living organism are now present, which could ever have been present. But if (and Oh! what a big if!) we could conceive in some warm little pond with all sorts of ammonia and phosphoric salts—light, heat, electricity &c. present, that a proteine compound was chemically formed, ready to undergo still more complex changes, at the present day such matter w^d be instantly devoured, or absorbed, which would not have been the case before living creatures were formed.” Although Darwin refrained from any further public statements on how life may have appeared, his views established the framework that would lead to a number of attempts to explain the origin of life by introducing principles of historical explanation (Peretó et al. 2009). Here I will describe this history, and how it is guiding current research into the question of life’s origins.     

Humboldt,Darwin, and population

Conclusions I have attempted to clarify some of the pathways in the development of Darwin's thinking. The foregoing examples of influence by no means include all that can be found by comparing Darwin's writings with Humboldt's. However, the above examples seem adequate to show the nature and extent of this influence. It now seems clear that Humboldt not only, as had been previously known, inspired Darwin to make a voyage of exploration, but also provided him with his basic orientation concerning how and what to observe and how to write about it. An important part of what Darwin assimilated from Humboldt was an appreciation of population analysis as a tool for assessing the state of societies and of the benefits and hardships which these societies can expect to receive from the living world around them.Darwin exhibited in his Journal of Researches a casual interest in the economic and political conditions of the countries he visited, but these considerations were much less important to him than to Humboldt. Instead, Darwin, with the assistance of Lyell's Principles of Geology, shifted from Humboldt's largely economic framework to a biological one built around the species question. This shift led Darwin away from a consideration of how the population biology of animals was related to man's economy to focus instead upon how population biology fitted into the economy of nature.Humboldt's Personal Narrative served very well as a model for Darwin's Journal of Researches, thereby helping Darwin gain scientific eminence. The Journal of Researches, like virtually all of Humboldt's writings, was a contribution to scientific orthodoxy. But Darwin had, along the way, acquired an urge to do more than just add his building blocks to the orthodox scientific edifice. He decided to rearrange those blocks of knowledge into a different structure, and for that task neither Humboldt's Personal Narrative nor any other of his works could serve as a model. Humboldt had lacked the confidence which Darwin needed that biogeography and the origin of species could be understood. Humboldt had not explored very far the possible connections between biology and geology. Nor had he provided a general synthetic account of population biology. Had he done so, he might have been more explicit about the extent of his endorsement of Malthus. But even if he had, Humboldt's strong orientation toward cooperation would probably have inhibited his recognition of the importance of competition in nature.Lyell, who had also benefited from reading Humboldt, gave Darwin insights that were lacking in Humboldt's Personal Narrative. Lyell admirably demonstrated how stratigraphy, paleontology, biogeography, and population biology could be interrelated, and his reasons for doing so were essentially the same as Darwin's. Lyell's understanding of biogeography and ecology came from the writings of Augustin-Pyramus de Candolle as much as from Humboldt's, and from the former Lyell derived an appreciation for the importance of competition and also a confidence that the mysteries of biogeography could be explained.¹¹⁷ Furthermore, Lyell's discussion of all these subjects and also of evolution in his Principles of Geology is a good synthetic argument that was the ideal model for Darwin's greatest book.Darwin, having become convinced that species change through time, was able to synthesize in his mind the contributions which he had derived from the writings of Humboldt and Lyell as they applied to the species question. When Darwin wrote his Journal of Researches there were two large gaps in his thinking about evolution that bothered him—the mechanism of evolution and the causes of extinction. It was only after reading Malthus in 1838 that he realized, as Lyell had more or less pointed out, how important was competition in nature. He now had the general outlines for his theory, and in the 1845 abridged edition of his Journal, now retitled The Voyage of the Beagle, he inserted a fuller discussion of competition in nature which showed his awareness of its importance as an ecological factor.¹¹⁸ An abridged version of this paper was presented at the meeting of the History of Science Society in Washington, D.C., on 29 December 1969.     

Song in two cryptic species: comparative analysis of Large-billed Reed Warblers Acrocephalus orinus and Blyth’s Reed Warblers Acrocephalus dumetorum

Capsule: Songs of Large-billed Reed Warblers Acrocephalus orinus and Blyth’s Reed Warblers Acrocephalus dumetorum differed in quantitative parameters. Blyth’s Reed Warbler used different modes of singing on breeding grounds and migration stopovers.

Aims: To compare the songs of two cryptic species of reed warblers. To compare Blyth’s Reed Warbler songs in different parts of the breeding range and on migration stopovers in central Asia. To investigate the status of Blyth’s Reed Warblers in central Asia.

Methods: We analysed song recordings of individual singing males and conducted field observations of singing behaviour at migration stopover and breeding sites. The status of Blyth’s Reed Warblers in central Asia was reviewed from the historical Russian literature and other sources.

Results: We found differences between six out of eight variables in songs of Large-billed and Blyth’s Reed Warblers on breeding sites. Blyth’s Reed Warbler songs recorded on migration stopovers showed differences in five variables from Large-billed Reed Warblers and in six variables from breeding Blyth’s Reed Warblers. On migration stopovers, Blyth’s Reed Warblers sang actively but did not stay more than 1–2 days. The evidence suggests that Blyth’s Reed Warbler does not breed in central Asia.

Conclusion: Songs of Large-billed and Blyth’s Reed Warblers could be distinguished by quantitative analysis. Blyth’s Reed Warblers used different modes of singing on breeding sites and migration stopovers. We believe vocalizations of Blyth’s Reed Warblers on migration to be plastic song.     

Monkeys into Men and Men into Monkeys: Chance and Contingency in the Evolution of Man, Mind and Morals in Charles Kingsley’s Water Babies

The nineteenth century theologian, author and poet Charles Kingsley was a notable populariser of Darwinian evolution. He championed Darwin’s cause and that of honesty in science for more than a decade from 1859 to 1871. Kingsley’s interpretation of evolution shaped his theology, his politics and his views on race. The relationship between men and apes set the context for Kingsley’s consideration of these issues. Having defended Darwin for a decade in 1871 Kingsley was dismayed to read Darwin’s account of the evolution of morals in Descent of Man. He subsequently distanced himself from Darwin’s conclusions even though he remained an ardent evolutionist until his death in 1875.     

Charles Darwin’s bird collection and ornithological knowledge during the voyage of H.M.S. “Beagle”, 1831–1836

This paper analyses Charles Darwins bird collection and the ornithological knowledge he derived from it during the voyage of H.M.S. Beagle. Darwin collected 468 bird skins, 10 detached parts of the lesser rhea, and the nests and eggs of 16 different taxa as well as 14 whole birds and 4 parts of birds which he preserved in spirit. He labelled these specimens with a number tag only, cross-referring the number to a notebook entry. Partly because of his limited ornithological knowledge and partly because he was confronted at times with entirely unknown birds, Darwin was often unable to apply the correct generic designations and gave his South American specimens English and Spanish names from literature and the local tongues, as well as the scientific generic names of European birds. Back home, it was John Gould, the prominent ornithologist of the Zoological Society of London, who made sense of Darwins collection, among his many other scientific achievements correctly identifying the Galápagos finches as a group of closely related birds. Darwins bird collection did not receive much attention in the latter part of the 19th century. Most of the specimens had their original labels removed and replaced by ones of the custodian institution. Today, original Darwin specimens stemming from the Beagle voyage are to be found in at least eight different institutions, but almost half of the bird specimens Darwin collected on the Beagle voyage are not accounted for. The appendix to this paper lists for the first time all the birds which Darwin collected during the voyage. Darwins famous book On the origin of species hardly draws upon any ornithological examples from his voyage on the Beagle. Nevertheless, Darwin contributed much to ornithology. His collection contained 39 new species and subspecies of birds, mainly described by Gould, and some birds from populations now extinct, and he also made a few very good field observations, published in the sections of The Zoology of the Voyage of H.M.S. Beagle dedicated to birds.

Gene Flow Happens

Debate over what is a species was already considered old hat when Darwin wrote his seminal abstract (as he called it) more than 150 years ago.¹ Endless papers, workshops, and symposia have been presented in an effort to "solve" the species problem. Yet, here we are, at it again. Has there been any progress? I believe that there has been, and that among the many advances enabled by the genomics revolution, progress on species concepts and species recognition is among them. To quote Feder and colleagues,² we are on the brink of a “unified theory of speciation genomics.”     

Demythologizing environmentalism

Conclusion In the early 1950s Grant McConnell, Jr., called for a political adjudication of our environmental and political visions. He pointed out the arbitrary nature of Gifford Pinchot's noble-sounding formula (The greatest good for the greatest number over the longest time), noting that such a determination depended on whom you asked. No technocrat can determine the greatest good on the basis of some secret expertise or privileged knowledge. We need to resolve our disparate visions of the uses of nature and human beings politically, without recourse to privileged knowledge.But does such a political adjudication imply the unimpeded domination of the will of the majority? Not necessarily, because there is no overall majority for a total bundle of policies and programs — these must be horse-traded and haggled over on the basis of shifting coalitions. Yet, can it not be argued that even so, some very deeply held values of minorities will be trounced and trampled? It would be dishonest not to admit to such a danger. What we must do is try to define and develop a workable conception of baseline human rights that will be inviolable by the will of temporary majorities, and this itself is a tenuous political process which we have only just embarked on in recent times.The danger of Valentin Rasputins, Vernadskii cultists, and Deep Ecologists everywhere is that they are arguing from privileged knowledge. We know what is really best for you, what will cure you, they assert. They alone know the distinction between natural harmony and disorder, social health and corruption, pollution and purity, alienation and unity. They do not recognize the social construction of their ethical beliefs and political visions; they absolutize their individual truths. They may be right, but what if they are not...?It is therefore all the more important for those of us who wish to preserve a maximum of biotic and human diversity for our-selves and for future humans (and nonhumans) to be explicit about the moral and political agendas we embrace. The soundest way for us to prevail is to persuade our neighbors on this planet that our visions have something of value for them, too. We must keep in mind the fact that in a world where there exists more than one fanaticism, peaceful coexistence is in principle impossible.And if fanaticisms, including ecological ones, are the products of the fear or the fact of material, cultural, or spiritual dispossession, then we must work harder to make a world in which each of us and our interests are treated with equal respect. We cannot get there through the tainted means of absolutizing individual truths.Aldo Leopold, in his testament Sand County Almanac, as much as called for a new myth, for us to think like a mountain.⁵⁷ He called for a new myth because he believed that humans were dangerous (to ourselves, first of all, and to the planet), and that inculcating a myth was the only way to effect a deep behavioral change on a massive enough scale to save the situation.⁵⁸ It is my belief that myths are often more dangerous than the situations they seek to remedy. We need to cultivate a taste of de-mythologizing, of making our lives more self-aware. We need to become aware of our needs and our value preferences and to take responsibility for them as individual preferences. Then we will be in a good position indeed to respect and compromise with the preferences of our neighbors all around this planet, just as we would have them respect and compromise with ours. *** DIRECT SUPPORT *** A8402064 00005 *** DIRECT SUPPORT *** A8402064 00006 *** DIRECT SUPPORT *** A8402064 00007     

The “Domestication Syndrome” in Mammals: A Unified Explanation Based on Neural Crest Cell Behavior and Genetics

Charles Darwin, while trying to devise a general theory of heredity from the observations of animal and plant breeders, discovered that domesticated mammals possess a distinctive and unusual suite of heritable traits not seen in their wild progenitors. Some of these traits also appear in domesticated birds and fish. The origin of Darwin’s “domestication syndrome” has remained a conundrum for more than 140 years. Most explanations focus on particular traits, while neglecting others, or on the possible selective factors involved in domestication rather than the underlying developmental and genetic causes of these traits. Here, we propose that the domestication syndrome results predominantly from mild neural crest cell deficits during embryonic development. Most of the modified traits, both morphological and physiological, can be readily explained as direct consequences of such deficiencies, while other traits are explicable as indirect consequences. We first show how the hypothesis can account for the multiple, apparently unrelated traits of the syndrome and then explore its genetic dimensions and predictions, reviewing the available genetic evidence. The article concludes with a brief discussion of some genetic and developmental questions raised by the idea, along with specific predictions and experimental tests.A major gap in Charles Darwin’s theory of evolution, as presented in the first edition of The Origin of Species (Darwin 1859), was the absence of a theory of heredity. As Darwin knew, his theory of evolution required a distinct idea of how biological heredity worked, but in 1859 he was not prepared to offer one. His attempt to fill this gap came subsequently, in his massive, detailed study of inheritance, The Variation of Plants and Animals under Domestication (Darwin 1868). Written decades before there was a science of genetics, it relied primarily on the data produced by animal and plant breeders, hence on observations of domesticated animals and plants.Darwin’s encyclopedic investigation of domesticated species revealed an intriguing phenomenon. From his survey of the animal breeding work, he found that domesticated mammals in general exhibit a suite of behavioral, physiological, and morphological traits not observed in their wild forebears. Today, the full set of these characteristics is known to include: increased docility and tameness, coat color changes, reductions in tooth size, changes in craniofacial morphology, alterations in ear and tail form (e.g., floppy ears), more frequent and nonseasonal estrus cycles, alterations in adrenocorticotropic hormone levels, changed concentrations of several neurotransmitters, prolongations in juvenile behavior, and reductions in both total brain size and of particular brain regions. The consistency of this extremely diverse set of phenotypic changes in domesticated mammals presents a major puzzle, as Darwin recognized. The suite seems to reflect something about the process of domestication per se, a conclusion strengthened by the finding that domesticated birds and even fish share some components of this spectrum of traits. Because Darwin published these findings just a few years after Mendel published his work, the hereditary basis of this phenomenon constitutes one of the oldest problems in genetics.The general combination of traits in domesticated mammals is an ensemble that we will refer to as the “domestication syndrome” (DS) (adopting a term used for domesticated crop plants, e.g., Brown et al. 2008). We list its core components in Table 1List of traits modified in the “domestication syndrome” in mammals^*