This article illuminates why Nicolás Palacios’s 1904 monograph, Raza chilena:Libro escrito por un Chileno i para los Chilenos [Chilean Race: A Book Written by a Chilean for Chileans], is central to the creation of a myth of Chilean racial homogeneity at the turn of the twentieth century. Placing Palacios in the context of Latin American eugenic discourse, it demonstrates how he selected a specific racial origin story in order to accommodate his belief in racial hierarchy while also depicting race mixing (...) in a positive light. Specifically, the article highlights how the myth of Chilean racial homogeneity elided the difference between the term “mestizo,” which was applied to people of mixed racial heritage, and “white.” I contend that Palacios sought to differentiate Chileans from other Latin Americans by emphasizing their racial distinctiveness. The article therefore highlights that Latin American eugenics was concerned with the creation of national narratives that historicized particular racial mixtures in order to reify and affirm national differences. As such, it connects to literature regarding the history of eugenics, race, nation, and the creation of whiteness. (shrink)

This paper contributes to two debates: the debate about language evolution and the debate about the foundations of human collaboration. While both cooperation and language may give the impression of being adaptations that evolved for the “good of the group,” it is well established that the evolution of complex traits cannot be a direct result of group selection. In this paper I suggest how this tension can be solved: both language and cooperation evolved in a unique two-level evolutionary system which (...) was triggered by a well-documented geological event—the drying out of the climate—in East Africa, which subsequently reduced the intermating between groups and thus made it possible that the mechanism that produced differences between groups could be the target of natural selection on the group level. If a social form of selection produced differences in fitness between groups, the displacement process between groups would indirectly select those forms of social selection that produce groups that would displace all others. The main hypothesis presented in this paper is that, in this situation, a backchannel between the two levels of selection naturally evolves. A backchannel between the two levels would, for example, emerge when sexual selection was sensitive to the individual’s contribution to the group. Examples of systems utilizing a backchannel are nerve cells being better nourished when used more frequently, enabling them to be conducive to the survival of the whole organism, or a law firm in which all employees get paid to the extent that they contribute to the survival and success of the firm. In both cases, the selection on the higher level informs the selection on the lower level. The aim of the paper is to illuminate these rather opaque claims, to which the reader probably has many objections in this abridged form. (shrink)

Of all contemporary social theorists, Luhmann has best understood the centrality of the concept of meaning to social theory and has most extensively worked out the notion's implications. However, despite the power of his theory, the theory suffers from difficulties impeding its reception. This article attempts to remedy this situation with some critical arguments and proposals for revision. First, the theory Luhmann adopted from biology as the basis of his own theory was a poor choice since that theory has no (...) explanatory power, being purely descriptive; furthermore, that theory is fundamentally flawed since it implies that viruses are impossible. Second, Luhmann's theory of meaning cannot coherently make the social domain autonomous as he desires since Luhmann does not take into account the distinction between syntax and semantics. By introducing this distinction, making clear that social systems consist of rules, not just communications, and raising the rule concept to the same prominence in social theory as those of actor and system, autonomy can be maintained while avoiding the counterintuitive aspects of Luhmann's theory. (shrink)

The progress towards mathematization or, in a broader context, towards an increased “objectivity” is one of the main trends in the development of biological systematics in the past century. It is commonplace to start the history of numerical taxonomy with the works of R. R. Sokal and P. H. A. Sneath that in the 1960s laid the foundations of this school of taxonomy. In this article, I discuss the earliest research program in this field, developed in the 1920s by the (...) Russian entomologist and biometrician Eugen (Evgeniy Sergeevich) Smirnov. The theoretical and methodological grounds of this program are considered based on the published works of Smirnov as well as some archival sources. The influence of Smirnov’s evolutionary (mechano-Lamarckian) convictions on the development of this project of “exact systematics” is analyzed as well as the author’s attempts to establish a novel concept of “mathematical essentialism” in animal taxonomy. The probable causes of the failure of Smirnov’s project are viewed from both externalist and internalist perspectives, including the opposition to the use of quantitative methods in biology by some of the Lysenkoist ideologists in the USSR. A brief comparison of Smirnov’s research program with that developed 40 years later by Sokal and Sneath is provided. (shrink)

Darwin provided us with a powerful theoretical framework to explain the evolution of living systems. Natural selection alone, however, has sometimes been seen as insufficient to explain the emergence of new levels of selection. The problem is one of “circularity” for evolutionary explanations: how to explain the origins of Darwinian properties without already invoking their presence at the level they emerge. That is, how does evolution by natural selection commence in the first place? Recent results in experimental evolution suggest a (...) way forward: Paul Rainey and his collaborators have shown that Darwinian properties could be exogenously imposed via what they call “ecological scaffolding.” This could solve the “black box” dilemma faced by Darwinian explanations of new levels of organization. Yet, despite “scaffolding” recently becoming a popular term in the study of cognition, culture, and evolution, the concept has suffered from vagueness and ambiguity. This article aims to show that scaffolding can be turned into a proper scientific concept able to do explanatory work within the context of the major evolutionary transitions. Doing so will allow us to once again extend the scope of the Darwinian model of evolution by natural selection. (shrink)

In 1869, Johann Friedrich Miescher discovered a new substance in the nucleus of living cells. The substance, which he called nuclein, is now known as DNA, yet both Miescher’s name and his theoretical ideas about nuclein are all but forgotten. This paper traces the trajectory of Miescher’s reception in the historiography of genetics. To his critics, Miescher was a “contaminator,” whose preparations were impure. Modern historians portrayed him as a “confuser,” whose misunderstandings delayed the development of molecular biology. Each of (...) these portrayals reflects the disciplinary context in which Miescher’s work was evaluated. Using archival sources to unearth Miescher’s unpublished speculations—including an analogy between the hereditary material and language, and a speculation that a series of asymmetric carbon atoms could account for hereditary variation—this paper clarifies the ways in which the past was judged through the lens of contemporary concerns. It also shows how organization, structure, function, and information were already being considered when nuclein was first discovered nearly 150 years ago. (shrink)

Many people who claim that evolution and theism are in tension assume that God, being omnipotent, could create life in different ways. For instance, Paul Draper has argued that the fact that life evolved on earth supports naturalism over theism. However, for there to be a probabilistic tension between naturalism and theism, because of the fact of evolution, a certain background assumption must be true, namely, that God could have made biological organisms and species through an act of Genesis-style special (...) creation, or some combination of evolution and special creation. But that background assumption is potentially faulty. Why? Because special creation presupposes that biological organisms and species are spatiotemporally unrestricted entities, and if the dominant paradigm in biology, and philosophy of biology, on the ontological status of organisms and species is correct, then they are spatiotemporally restricted entities. (shrink)

Industrial melanism, according to the traditional explanation, amounts to niche construction since it involves changes in predation pressure. Indeed, it would be difficult to imagine selection without niche construction. This cannot be what Laland, Odling-Smee & Feldman mean. They offer convincing examples, but they should provide a better definition of “niche construction” to indicate how their view supplements traditional evolutionary biology.

Instances of explanatory reduction are often advocated on metaphysical grounds; given that the only real things in the world are subatomic particles and their interaction, we have to try to explain everything in terms of the laws of physics. In this paper, we show that explanatory reduction cannot be defended on metaphysical grounds. Nevertheless, indispensability arguments for reductive explanations can be developed, taking into account actual scientific practice and the role of epistemic interests. Reductive explanations might be indispensable to address (...) some epistemic interest answering a specific explanation-seeking question in the most accurate, adequate and efficient way. Just like explanatory pluralists often advocate the indispensability of higher levels of explanation pointing at the pragmatic value of the explanatory information obtained on these higher levels, we argue that explanatory reduction—traditionally understood as the contender of pluralism—can be defended in a similar way. The pragmatic value reductionist, lower level explanations might have in the biomedical sciences and the social sciences is illustrated by some case studies. (shrink)

Ernst Mayr argued that the emergence of biology as a special science in the early nineteenth century was possible due to the demise of the mathematical model of science and its insistence on demonstrative knowledge. More recently, John Zammito has claimed that the rise of biology as a special science was due to a distinctive experimental, anti-metaphysical, anti-mathematical, and anti-rationalist strand of thought coming from outside of Germany. In this paper we argue that this narrative neglects the important role played (...) by the mathematical and axiomatic model of science in the emergence of biology as a special science. We show that several major actors involved in the emergence of biology as a science in Germany were working with an axiomatic conception of science that goes back at least to Aristotle and was popular in mid-eighteenth-century German academic circles due to its endorsement by Christian Wolff. More specifically, we show that at least two major contributors to the emergence of biology in Germany—Caspar Friedrich Wolff and Gottfried Reinhold Treviranus—sought to provide a conception of the new science of life that satisfies the criteria of a traditional axiomatic ideal of science. Both C.F. Wolff and Treviranus took over strong commitments to the axiomatic model of science from major philosophers of their time, Christian Wolff and Friedrich Wilhelm Joseph Schelling, respectively. The ideal of biology as an axiomatic science with specific biological fundamental concepts and principles thus played a role in the emergence of biology as a special science. (shrink)

For over a century it has been believed that Alfred Russel Wallace and Henry Walter Bates set out for the Amazon in 1848 with the aim of “solving the problem of the origin of species”. Yet this enticing story is based on only one sentence. Bates claimed in the preface to his 1863 book that Wallace stated this was the aim of their expedition in an 1847 letter. Bates gave a quotation from the letter. But Wallace himself never endorsed or (...) repeated this story. Many writers have acknowledged that this letter still survives. Yet the wording is different from that quoted by Bates and the letter says nothing of an expedition. It is argued that the sentence given by Bates is not a genuine quotation from this or any other Wallace letter but was modified by Bates to promote his own reputation. More significantly, this leads to the conclusion that there was a very sudden and dramatic shift in the way species were thought of and discussed after Darwin’s Origin of species appeared. Something called “the problem of the origin of species” never occurred before Darwin’s book but exploded in frequency immediately after it. A profound change in how species origins were discussed happened which no one seemed to notice. (shrink)

The theoretical status of ‘niche construction’ in evolution is intensely debated. Here we substantiate the reasons for different interpretations. We consider two concepts of niche construction brought to bear on evolutionary theory; one that emphasizes how niche construction contributes to selection and another that emphasizes how it contributes to development and inheritance. We explain the rationale for claims that selective and developmental niche construction motivate conceptual change in evolutionary biology and the logic of those who reject these claims. Our analysis (...) shows how the contention arises from alternative assumptions regarding the causal independence of the processes that generate variation, differential fitness and inheritance. (shrink)

Se ha impuesto la imagen del código de barras para hacer referencia a una secuencia de ADN mitocondrial que es utilizada para medir la distancia genética entre poblaciones animales. Según la interpretación esencialista de esta analogía, este método de medición serviría, por sí mismo, no solo para la rápida identificación de ejemplares, o muestras fragmentarias, de especies previamente clasificadas, sino también para el descubrimiento de nuevas especies. Los taxónomos integrativos han rechazado este último uso del método del código de barras (...) de ADN, dado que la complejidad biológica impide aplicarlo con precisión en eventos de especiación recientes. Argumentaré, sin embargo, que el método falla por razones conceptuales y no meramente empíricas. Aunque no existiera ese impedimento empírico, el código de barras de ADN no podría ser un método de descubrimiento de especies. (shrink)

In a macroevolutionary timescale, evolvability itself evolves. Lineages are sorted based on their ability to generate adaptive novelties, which leads to the optimization of their genotype-phenotype map. The system of translation of genetic or epigenetic changes to the phenotype may reach significant horizontal and vertical complexity, and may even exhibit certain aspects of learning behaviour. This continuously evolving semiotic system probably enables the origin of complex yet functional and internally compatible adaptations. However, it also has a second, “darker”, side. As (...) was pointed out by several authors, the same process gradually reduces the probability of the origination of significant evolutionary novelties. In a similar way to the evolution of societies, teachings, or languages, in which the growing number of internal linkages gradually solidifies their overall structure and the structure or interpretation of their constitutive elements, the evolutionary potential of lineages decreases during biological evolution. Possible adaptations become limited to small “peripheral” modifications. According to the Frozen Evolution theory, some of the proximate causes of this “macroevolutionary freezing” are more pronounced or present exclusively in sexual lineages. Sorting based on the highest evolvability probably leads to the establishment of certain structural features of complex organisms, e.g. the modular character of their development and morphology. However, modules also “macroevolutionary freeze” whereas the hypothetical “thawing” of modules or their novel adaptive combinations becomes rarer and rarer. Some possible ways out of this dead end include the rearrangement of individual development, e.g. neoteny, radical simplification, i.e. sacculinization, and transition to a higher level of organization, e.g. symbiosis or symbiogenesis. The evolution of evolvability is essentially a biosemiotic process situated at the intersection of the genocentric modern synthesis and the evo-devo-centric extended synthesis. Therefore, evolvability may eventually connect these three not necessarily contradictory approaches. (shrink)

The experimental method is designed to secure the reliable attribution of causal relationships by means of controlled comparison across conditions. Doing so, however, depends upon the reduction of uncertainties and inconsistencies in the process of comparison; and this poses particularly significant challenges for the behavioral and social sciences because they work with human subjects, whose malleability and complexity often interact in unexpected ways with experimental manipulations, thus resulting in unpredictable behavior. Drawing on the Science and Technology Studies perspective and one (...) of our authors’ experiences in experimental work, this paper examines how experimental social scientists manage to establish objectivity and standardization in the face of vagaries arising from working with human subjects. In identifying experimental researchers’ solutions to this challenge, we draw on methodological discussions among applied social scientists as naturally occurring data, through which we show how some seemingly mundane practices play essential roles in extracting patterns out of otherwise unpredictable behaviors in the lab. Closely examining such strategies, we reveal the inherent instabilities in the experimental method when adopted in the social sciences and discuss their methodological implications. In conclusion, we make tentative suggestions for escaping the kinds of methodological impasses which we have identified. (shrink)

Modern evolutionary theory is both a central theory and an integrative framework of the life sciences. This is reflected in the common references to evolution in modern science education curricula and contexts. In fact, evolution is a core idea that is supposed to support biology learning by facilitating the organization of relevant knowledge. In addition, evolution can function as a pivotal link between concepts and highlight similarities in the complexity of biological concepts. However, empirical studies in many countries have for (...) decades identified deficiencies in students’ scientific understanding of evolution mainly focusing on natural selection. Clearly, there are major obstacles to learning natural selection, and we argue that to overcome them, it is essential to address explicitly the general abstract concepts that underlie the biological processes, e.g., randomness or probability. Hence, we propose a two-dimensional framework for analyzing and structuring teaching of natural selection. The first—purely biological—dimension embraces the three main principles variation, heredity, and selection structured in nine key concepts that form the core idea of natural selection. The second dimension encompasses four so-called thresholds, i.e., general abstract and/or non-perceptual concepts: randomness, probability, spatial scales, and temporal scales. We claim that both of these dimensions must be continuously considered, in tandem, when teaching evolution in order to allow development of a meaningful understanding of the process. Further, we suggest that making the thresholds tangible with the aid of appropriate kinds of visualizations will facilitate grasping of the threshold concepts, and thus, help learners to overcome the difficulties in understanding the central theory of life. (shrink)

Evolutionary theory predicts that humans should avoid incest because of the negative effects incest has on individual reproduction: production of defective offspring. Selection for the avoidance of close-kin mating has apparently resulted in a psychological mechanism that promotes voluntary incest avoidance. Most human societies are thought to have rules regulating incest. If incest is avoided, why are social rules constructed to regulate it? This target article suggests that incest rules do not exist primarily to regulate close-kin mating but to regulate (...) inbreeding between more distant kin and sexual relations between affinal relatives. Three evolutionary hypotheses about cousin marriage and affinal kin mating follow from this suggestion: Rules regulating mating between affinal kin are means of paternity protection. Cousin marriage is regulated because, if it occurs, it can concentrate wealth and power within families to the detriment of the powerful positions of rulers in stratified societies and the relatively equal social statuses of most men in egalitarian societies. Tests using the comparative method on a worldwide sample of 129 societies supported the three hypotheses. Two alternative anthropological hypotheses failed to be supported. (shrink)

Model organisms are a living form of scientific models. Despite the widespread use of model organisms in scientific research, the actual representational relationship between model organisms and their target species is often poorly characterized in the context of cross-species research. Many model organisms do not represent the target species adequately, let alone accurately. This is partly due to the complex and emergent life phenomena in the organism, and partly due to the fact that a model organism is always taken to (...) represent a broad range of diverse organisms. More often than not, model organisms are taken as a reference point for an extrapolation to be made to the unknown characteristics of other species. I propose to view model organisms as analogue simulators which represent the emergent phenomenon in the context of cross-species research. A model organism represents a wide range of species by simulating their molecular microstates which underlie various emergent phenomena. I show that although model organisms represent the target species inadequately at many levels of complexity, they have epistemic values as a simulator in virtue of which the emergent phenomenon can be modeled dynamically, a virtue that is hardly attainable by non-dynamic models. (shrink)

Welch :263–279, 2017) has recently proposed two possible explanations for why the field of evolutionary biology is plagued by a steady stream of claims that it needs urgent reform. It is either seriously deficient and incapable of incorporating ideas that are new, relevant and plausible or it is not seriously deficient at all but is prone to attracting discontent and to the championing of ideas that are not very relevant, plausible and/or not really new. He argues for the second explanation. (...) This paper presents a twofold critique of his analysis: firstly, the main calls for reform do not concern the field of evolutionary biology in general but rather, or more specifically, the modern evolutionary synthesis. Secondly, and most importantly, these calls are not only inspired by the factors, enumerated by Welch, but are also, and even primarily, motivated by four problematic characteristics of the modern synthesis. This point is illustrated through a short analysis of the latest reform challenge to the modern synthesis, the so-called extended evolutionary synthesis. We conclude with the suggestion that the modern synthesis should be amended, rather than replaced. (shrink)

Traditionally, Thomas S. Kuhn’s The Structure of Scientific Revolutions (1962) is largely identified with his analysis of the structure of scientific revolutions. Here, we contribute to a minority tradition in the Kuhn literature by interpreting the history of evolutionary biology through the prism of the entire historical developmental model of sciences that he elaborates in The Structure. This research not only reveals a certain match between this model and the history of evolutionary biology but, more importantly, also sheds new light (...) on several episodes in that history, and particularly on the publication of Charles Darwin’s On the Origin of Species (1859), the construction of the modern evolutionary synthesis, the chronic discontent with it, and the latest expression of that discontent, called the extended evolutionary synthesis. Lastly, we also explain why this kind of analysis hasn’t been done before. (shrink)

For the last 50 years the dominant stance in experimental biology has been reductionism in general, and genetic reductionism in particular. Philosophers were the first to realize that the belief that the Mendelian genes were reduced to DNA molecules was questionable. Soon, experimental data confirmed these misgivings. The optimism of molecular biologists, fueled by early success in tackling relatively simple problems has now been tempered by the difficulties encountered when applying the same simple ideas to complex problems. We analyze three (...) examples taken from experimental data that illustrate the shortcomings of this sort of reductionism. In the first, alterations in the expression of a large number of genes coexist with normal phenotypes at supra-cellular levels of organization; in the second, the supposed intrinsic specificity of hormonal signals is negated; in the third, the notion that cancer is a cellular problem caused by mutated genes is challenged by data gathered both from the reductionist viewpoint and the alternative view proposing that carcinogenesis is development gone awry. As an alternative to reductionism, we propose that the organicist view is a good starting point from which to explore these phenomena. However, new theoretical concepts are needed to grapple with the apparent circular causality of complex biological phenomena. (shrink)

We explore the evidential relationships that connect two standard claims of modern evolutionary biology. The hypothesis of common ancestry (which says that all organisms now on earth trace back to a single progenitor) and the hypothesis of natural selection (which says that natural selection has been an important influence on the traits exhibited by organisms) are logically independent; however, this leaves open whether testing one requires assumptions about the status of the other. Darwin noted that an extreme version of adaptationism (...) would undercut the possibility of making inferences about common ancestry. Here we develop a converse claim—hypotheses that assert that natural selection has been an important influence on trait values are untestable unless supplemented by suitable background assumptions. The fact of common ancestry and a claim about quantitative genetics together suffice to render such hypotheses testable. Furthermore, we see no plausible alternative to these assumptions; we hypothesize that they are necessary as well as sufficient for adaptive hypotheses to be tested. This point has important implications for biological practice, since biologists standardly assume that adaptive hypotheses predict trait associations among tip species. Another consequence is that adaptive hypotheses cannot be confirmed or disconfirmed by a trait value that is universal within a single species, if that trait value deviates even slightly from the optimum. 1 Two Darwinian hypotheses 2 Logical independence 3 How adaptive hypotheses bear on the tree of life hypothesis 4 How the tree of life hypothesis bears on adaptive hypotheses 5 What do adaptive hypotheses predict? 6 Common ancestry and quantitative genetics to the rescue 7 Conclusion. (shrink)

This paper attempts a critical examination of scholarly understanding of the historical event referred to as "the Darwinian Revolution." In particular, it concentrates on some of the major scholarly works that have appeared since the publication in 1979 of Michael Ruse's "The Darwinian Revolution: Nature Red in Tooth and Claw." The paper closes by arguing that fruitful critical perspectives on what counts as this event can be gained by locating it in a range of historiographic and disciplinary contexts that include (...) the emergence of the discipline of evolutionary biology (following the "evolutionary synthesis"), the 1959 Darwin centenary, and the maturation of the discipline of the history of science. Broader perspectives on something called the "Darwinian Revolution" are called for that include recognizing that it does not map a one-to-one correspondence with the history of evolution, broadly construed. (shrink)

This article re-contextualizes Sigmund Freud's interest in the idea of the inheritance of acquired characteristics in terms of the socio-political connotations of Lamarckism and Darwinism in the 1930s and 1950s. Many scholars have speculated as to why Freud continued to insist on a supposedly outmoded theory of evolution in the 1930s even as he was aware that it was no longer tenable. While Freud's initial interest in the inheritance of phylogenetic memory was not necessarily politically motivated, his refusal to abandon (...) this theory in the 1930s must be understood in terms of wider debates, especially regarding the position of the Jewish people in Germany and Austria. Freud became uneasy about the inheritance of memory not because it was scientifically disproven, but because it had become politically charged and suspiciously regarded by the Nazis as Bolshevik and Jewish. Where Freud seemed to use the idea of inherited memory as a way of universalizing his theory beyond the individual cultural milieu of his mostly Jewish patients, such a notion of universal science itself became politically charged and identified as particularly Jewish. The vexed and speculative interpretations of Freud's Lamarckism are situated as part of a larger post-War cultural reaction against Communism on the one hand (particularly in the 1950s when Lamarckism was associated with the failures of Lysenko), and on the other hand, against any scientific concepts of race in the wake of World War II. (shrink)

This article re-contextualizes Sigmund Freud's interest in the idea of the inheritance of acquired characteristics in terms of the socio-political connotations of Lamarckism and Darwinism in the 1930s and 1950s. Many scholars have speculated as to why Freud continued to insist on a supposedly outmoded theory of evolution in the 1930s even as he was aware that it was no longer tenable. While Freud's initial interest in the inheritance of phylogenetic memory was not necessarily politically motivated, his refusal to abandon (...) this theory in the 1930s must be understood in terms of wider debates, especially regarding the position of the Jewish people in Germany and Austria. Freud became uneasy about the inheritance of memory not because it was scientifically disproven, but because it had become politically charged and suspiciously regarded by the Nazis as Bolshevik and Jewish. Where Freud seemed to use the idea of inherited memory as a way of universalizing his theory beyond the individual cultural milieu of his mostly Jewish patients, such a notion of universal science itself became politically charged and identified as particularly Jewish. The vexed and speculative interpretations of Freud's Lamarckism are situated as part of a larger post-War cultural reaction against Communism on the one hand, and on the other hand, against any scientific concepts of race in the wake of World War II. (shrink)

The Greenough stereomicroscope, or “Stemi” as it is colloquially known among microscopists, is a stereoscopic binocular instrument yielding three-dimensional depth perception when working with larger microscopic specimens. It has become ubiquitous in laboratory practice since its introduction by the unknown scientist Horatio Saltonstall Greenough in 1892. However, because it enabled new experimental practices rather than new knowledge, it has largely eluded historical and epistemological investigation, even though its design, production, and reception in the scientific community was inextricably connected to the (...) new epistemological ideals of the life sciences caught between natural history and modern science. The development of the microscope will be contextualized within the scientific and technological landscape, showing how Greenough navigated his way through this terrain, and what led him to sow the seeds for the stereoscopic microscope. The historical controversy over the optical mechanism, through which the instrument would generate the desired depth perception, and how this quality was embedded into laboratory practice, will be examined. Subsequently, it will become evident that the specific image of nature produced by the stereoscopic microscope corresponded to the new ideals of the life sciences and their representation. (shrink)

Because of the problems associated with ecological concepts, generalizations, and proposed general theories, applied ecology may require a new "logic" of explanation characterized neither by the traditional accounts of confirmation nor by the logic of discovery. Building on the works of Grunbaum, Kuhn, and Wittgenstein, we use detailed descriptions from research on conserving the Northern Spotted Owl, a case typical of problem solving in applied ecology, to (1) characterize the method of case studies; (2) survey its strengths; (3) summarize and (...) respond to its shortcomings; and (4) investigate and defend its underlying "logic". (shrink)