This paper examines the history of animal behavior studies after the synthesis period. Three episodes are considered: the adoption of the theory of natural selection, the mathematization of ideas, and the spread of molecular methods in behavior studies. In these three episodes, students of behavior adopted practices and standards developed in population ecology and population genetics. While they borrowed tools and methods from these fields, they made distinct uses that set them relatively apart and led them to contribute, (...) in their own way, to evolutionary theory. These episodes also highlight some limitations of “conjunction narratives” centered on the relation between a discipline and the modern synthesis. A trend in conjunction narratives is to interpret any development related to evolution in a discipline as an “extension,” an “integration,” or as a “delayed” synthesis. I here suggest that this can lead to underestimate discontinuities in the history of evolutionary biology. (shrink)

This paper analyses the broad methodological structure of population-biological theorising. In it, I show that the distinction between initial exploratory, hypothesis-generating research and the subsequent process-reconstructing, hypothesis-testing type of research is not being made. Rather, the hypotheses generated in population biology are elaborated in such detail that students confound the initial research phase with the subsequent hypotheses-testing phase of research. In this context, I therefore analyse some testing procedures within the exploration phase and show that, as an (...) extreme form of confusion, statistical null-models are mistakenly given the status of causal population-biological theory. (shrink)

In this essay, I argue for four related claims. First, Richard Levins’ classic “The Strategy of Model Building in Population Biology” was a statement and defense of theoretical population biology growing out of collaborations between Robert MacArthur, Richard Lewontin, E. O. Wilson, and others. Second, I argue that the essay served as a response to the rise of systems ecology especially as pioneered by Kenneth Watt. Third, the arguments offered by Levins against systems ecology and in (...) favor of his own methodological program are best construed as “pragmatic”. Fourth, I consider limitations of Levins’ arguments given contemporary population biology. (shrink)

Ecologist Richard Levins argues population biologists must trade‐off the generality, realism, and precision of their models since biological systems are complex and our limitations are severe. Steven Orzack and Elliott Sober argue that there are cases where these model properties cannot be varied independently of one another. If this is correct, then Levins's thesis that there is a necessary trade‐off between generality, precision, and realism in mathematical models in biology is false. I argue that Orzack and Sober's arguments (...) fail since Levins's thesis concerns the pragmatic features of model building not just the formal properties of models. (shrink)

What is the role (or roles) of mathematical theory in ecology and evolutionary biology? How does the construction of such theory advance our understanding? The lack of clear answers to this pair of questions has been a source of controversy both within the sciences themselves, and in the philosophical discussions of these sciences as well. In an attempt to shed some light on these issues, I look at what some biologists have had to say on the matter and at (...) some particular examples. I then draw some morals about the constraints on a successful philosophical treatment of the problem and on the limitations of current philosophical approaches to this type of theoretical explanation. (shrink)

The scope of this paper can be clarified by means of a well-known phenomenon that is usually called ‘industrial melanism’: the fact that the melanic form of the peppered moth became dominant in industrial areas in England in the second half of the nineteenth century. Such changes in relative phenotype frequencies are important explananda for population biologists. Apart from trying to explain such changes over time, population biologists also often try to explain differences between populations, e.g. why yellow (...) shell colour is dominant in certain colonies of land snails and almost absent in other colonies. The causal explanations that are given to address such explananda are the objects of analysis in this paper. Our primary aim is to explicate their structure: we want to capture the typical ingredients of causal explanations in population biology, and their organisation. Based on this explication, we discuss how natural selection fits into recent mechanical philosophy of science, and engage in the debate on the nature of evolutionary theory. (shrink)

In our 1993 paper, “A Critical Look,‘ Elliott Sober and I concluded that the famous claim about model formulation and constraints made by Richard Levins in his influential 1966 article on model building in population biology is neither true nor normative. Here, I comment upon the claim of Odenbaugh that the conclusions of “A Critical Look‘ are incorrect. My conclusions remain that Levins’ claim about the tradeoff between model properties lacks logical coherence, generates an arbitrary model classification, and (...) lacks normative utility. Accordingly, I view his claim as providing no useful insight into the nature of models and model building in population biology. (shrink)

There is, at present, controversy surrounding the role of the mathematical models which typify the more theoretical portions of ecology and evolutionary biology. Within these sciences there has been controversy about the “testability” of these models, both in terms of the ability of the model to make precise enough claims about the world, and in terms of our ability to determine the values of theoretical parameters. There has been concern, particularly in ecology, about the lack of realism characteristic of (...) most models as well. These are, for the most part, issues involving the nature of theoretical explanation. Much of the current debate about null hypothesis testing, the unfalsifiability of theory, and the role of theory is symptomatic, it would seem, of the fact that these sciences have not settled on what to expect from their most mathematical theories. If there is one emerging theme, it is the need, again especially in ecology, for pluralistic theoretical treatments - which suggests that they may have been expecting too much. (shrink)

In this paper, I plan to show that the use of a specific population concept—Millstein’s Causal Interactionist Population Concept (CIPC)—has interesting and counter-intuitive ramifications for discussions of the reality of biological race in human beings. These peculiar ramifications apply to human beings writ large and to individuals. While this in and of itself may not be problematic, I plan to show that the ramifications that follow from applying Millstein’s CIPC to human beings complicates specific biological racial realist accounts—naïve (...) or otherwise. I conclude with the notion that even if biological races do exist—by fulfilling all of the criteria needed for Millstein’s population concept (which, given particular worries raised by Gannett (Synthese 177:363–385, 2010), and Winther and Kaplan (Theoria 60:54–80, 2013) may not)—the lower-bound limit for the scope of biological racial realism is at the level of populations, and as such they cannot say anything about whether or not individual organisms themselves have races. (shrink)

During the past few decades, philosophers of biology have debated the issue of reductionism versus anti-reductionism, with both sides often claiming a ‘pluralist’ position. However, both sides also tend to focus on a single research paradigm, which analyzes living things in terms of certain macromolecular components. I offer a case study where biologists pursue other analytic pathways, in a tradition of quantitative genetics that originates with the initially purely mathematical theories of R. A. Fisher, J. B. S. Haldane, and (...) Sewall Wright in the 1930s. Aster Models offers a class of statistical models designed for studying the fitness of plant and animal populations, by integrating the measurements of separate, sequential, non-normally distributed fitness components in novel ways. Their work generates important theoretical and practical results that do not require elaboration by molecular biology, and thus serves as a counterexample to the claims of philosophers whose ‘pluralism’ still harbors reductionist assumptions. (shrink)

This paper aims to illustrate one of the primary goals of the philosophy of biology⎯namely, the examination of central concepts in biological theory and practice⎯through an analysis of the concepts of population and metapopulation in evolutionary biology and ecology. I will first provide a brief background for my analysis, followed by a characterization of my proposed concepts: the causal interactionist concepts of population and metapopulation. I will then illustrate how the concepts apply to six cases that (...) differ in their population structure; this analysis will also serve to flesh out and defend the concepts a bit more. Finally, I will respond to some possible questions that my analysis may have raised and then conclude briefly. (shrink)

In view of the confusion about the use of the term ‘population’ in biology, an analysis has been made of the use of the concept of population in biology. Origin and development, logic and epistemology of the population-concept have been investigated for that purpose. It appears that several concepts of population coexist in biology. The term ‘population’ is used for all these concepts, so it is not amazing that confusion has arisen. This (...) confusion is the more dangerous, since ‘population’ plays an important part in the theory of evolution. A modus has been suggested to diminish this confusion by defining ‘population’ in a very wide sense of the term and by proposing a ‘deme’—terminology to specify the various special concepts of population. (shrink)

On the one hand, much has been written on Theodosius Dobzhansky’s central role in the development of the field of population genetics and modern evolutionary theory, as well as on his sociopolitical worldview in the middle of the Twentieth Century. On the other hand, much has also been written on Dobzhansky’s role in the institutionalization of genetics in Brazil, where he spent a considerable amount of time. Unfortunately, these literatures developed without any points of intersection or cross-reference. This article (...) places Dobzhansky’s work in Brazil in the broader contexts of the science and politics of its historical period. (shrink)

Biologists studying ecology and evolution use the term “population” in many different ways. Yet little philosophical analysis of the concept has been done, either by biologists or philosophers, in contrast to the voluminous literature on the concept of “species.” This is in spite of the fact that “population” is arguably a far more central concept in ecological and evolutionary studies than “species” is. The fact that such a central concept has been employed in so many different ways is (...) potentially problematic for the reason that inconsistent usages (especially when the usage has not been made explicit) might lead to false controversies in which disputants are simply talking past one another. However, the inconsistent usages are not the only, or even the most important reason to examine the concept. If any set of organisms is legitimately called a “population,” selection and drift processes become purely arbitrary, too. Moreover, key ecological variables, such as abundance and distribution, depend on a nonarbitrary way of identifying populations. I sketch the beginnings of a population concept, drawing inspiration from the Ghiselin-Hull individuality thesis, and show why some alternative approaches are nonstarters. (shrink)

This chapter contains section titled: Historical Overview Population Genetics Models The Tautology Problem The Wright‐Fisher Debate Classical/Balance Hypothesis Debate The Neutralism Controversy Saltationism vs. Gradualism Conclusions Acknowledgments References Further Reading.

This chapter contains section titled: Introduction Laws in Ecology Mathematical Models What is the Reason for Population Cycles? The Balance of Nature Debate Socio‐Political Aspects of Population Ecology Ecology and Evolution Acknowledgments References Further Reading.

Contemporary biology has inherited two key assumptions from the Modern Synthesis about the nature of population lineages: sexual reproduction is the exemplar for how individuals in population lineages inherit traits from their parents, and random mating is the exemplar for reproductive interaction. While these assumptions have been extremely fruitful for a number of fields, such as population genetics and phylogenetics, they are increasingly unviable for studying the full diversity and evolution of life. I introduce the “mixture” (...) account of population lineages that escapes these assumptions by dissolving the Modern Synthesis’s sharp line separating reproduction and development and characterizing reproductive integration in population lineages by the ephemerality of isolated subgroups rather than random mating. The mixture account provides a single criterion for reproductive integration that accommodates both sexual and asexual reproduction, unifying their treatment under Kevin de Queiroz’s generalized lineage concept of species. The account also provides a new basis for empirically assessing the effect of random mating as an idealization on the empirical adequacy of population genetic models. (shrink)

I defend a radical interpretation of biological populations—what I call population pluralism—which holds that there are many ways that a particular grouping of individuals can be related such that the grouping satisfies the conditions necessary for those individuals to evolve together. More constraining accounts of biological populations face empirical counter-examples and conceptual difficulties. One of the most intuitive and frequently employed conditions, causal connectivity—itself beset with numerous difficulties—is best construed by considering the relevant causal relations as ‘thick’ causal concepts. (...) I argue that the fine-grained causal relations that could constitute membership in a biological population are huge in number and many are manifested by degree, and thus we can construe population membership as being defined by massively multidimensional constructs, the differences between which are largely arbitrary. I end by showing that positions in two recent debates in theoretical biology depend on a view of biological populations at odds with the pluralism defended here. (shrink)

I defend a radical interpretation of biological populations—what I call population pluralism—which holds that there are many ways that a particular grouping of individuals can be related such that the grouping satisfies the conditions necessary for those individuals to evolve together. More constraining accounts of biological populations face empirical counter-examples and conceptual difficulties. One of the most intuitive and frequently employed conditions, causal connectivity—itself beset with numerous difficulties—is best construed by considering the relevant causal relations as ‘thick’ causal concepts. (...) I argue that the fine-grained causal relations that could constitute membership in a biological population are huge in number and many are manifested by degree, and thus we can construe population membership as being defined by massively multidimensional constructs, the differences between which are largely arbitrary. I end by showing that positions in two recent debates in theoretical biology depend on a view of biological populations at odds with the pluralism defended here. 1 Introduction2 Biological Population, Broad and Narrow3 Difficulties with Narrow Biological Population Conditions3.1 Against the genealogical condition3.2 Against the conspecificity condition3.3 Against the proximity condition3.4 Against the typology condition4 Causal Connectivity5 Massively Multidimensional Population Constructs6 Population Uniqueness and Natural Selection6.1 Statisticalism and its discontents6.2 Price at what price?7 Conclusion. (shrink)

The book presents a new way of understanding Darwinism and evolution by natural selection, combining work in biology, philosophy, and other fields.

The status of population genetics has become hotly debated among biologists and philosophers of biology. Many seem to view population genetics as relatively unchanged since the Modern Synthesis and have argued that subjects such as development were left out of the Synthesis. Some have called for an extended evolutionary synthesis or for recognizing the insignificance of population genetics. Yet others such as Michael Lynch have defended population genetics, declaring "nothing in evolution makes sense except in (...) the light of population genetics" (a twist on Dobzhansky's famous slogan that "nothing in biology makes sense except in the light of evolution"). Missing from this discussion is the use of population genetics to shed light on ecology and vice versa, beginning in the 1940s and continuing until the present day. I highlight some of that history through an overview of traditions such as ecological genetics and population biology, followed by a slightly more in-depth look at a contemporary study of the endangered California Tiger Salamander. I argue that population genetics is a powerful and useful tool that continues to be used and modified, even if it isn't required for all evolutionary explanations or doesn't incorporate all the causal factors of evolution. (shrink)

Two new modes of thinking have spread through systematics in the twentieth century. Both have deep historical roots, but they have been widely accepted only during this century. Population thinking overtook the field in the early part of the century, culminating in the full development of population systematics in the 1930s and 1940s, and the subsequent growth of the entire field of population biology. Population thinking rejects the idea that each species has a natural type (...) (as the earlier essentialist view had assumed), and instead sees every species as a varying population of interbreeding individuals. Tree thinking has spread through the field since the 1960s with the development of phylogenetic systematics. Tree thinking recognizes that species are not independent replicates within a class (as earlier group thinkers had tended to see them), but are instead interconnected parts of an evolutionary tree. It lays emphasis on the explanation of evolutionary events in the context of a tree, rather than on the states exhibited by collections of species, and it sees evolutionary history as a story of divergence rather than a story of development. Just as population thinking gave rise to the new field of population biology, so tree thinking is giving rise to the new field of phylogenetic biology. (shrink)

Ernst Mayr has argued that Darwinian theory discredited essentialist modes of thought and replaced them with what he has called "population thinking". In this paper, I characterize essentialism as embodying a certain conception of how variation in nature is to be explained, and show how this conception was undermined by evolutionary theory. The Darwinian doctrine of evolutionary gradualism makes it impossible to say exactly where one species ends and another begins; such line-drawing problems are often taken to be the (...) decisive reason for thinking that essentialism is untenable. However, according to the view of essentialism I suggest, this familiar objection is not fatal to essentialism. It is rather the essentialist's use of what I call the natural state model for explaining variation which clashes with evolutionary theory. This model implemented the essentialist's requirement that properties of populations be defined in terms of properties of member organisms. Requiring such constituent definitions is reductionistic in spirit; additionally, evolutionary theory shows that such definitions are not available, and, moreover, that they are not needed to legitimize population-level concepts. Population thinking involves the thesis that population concepts may be legitimized by showing their connections with each other, even when they are not reducible to concepts applying at lower levels of organization. In the paper, I develop these points by describing Aristotle's ideas on the origins of biological variation; they are a classic formulation of the natural state model. I also describe how the development of statistical ideas in the 19th century involved an abandoning of the natural state model. (shrink)

In the Preface of Animal Species and Evolution (1963), I wrote that it was "an attempt to summarize and review critically what we know about the biology and genetics of animal species and their role in evolution." The result was a volume of XIV ...

The concept of population thinking was introduced by Ernst Mayr as the right way of thinking about the biological domain, but it is difficult to find an interpretation of this notion that is both unproblematic and does the theoretical work it was intended to do. I argue that, properly conceived, Mayr’s population thinking is a version of trope nominalism: the view that biological property-types do not exist or at least they play no explanatory role. Further, although population (...) thinking has been traditionally used to argue against essentialism about biological kinds, recently it has been suggested that it may be consistent with at least some forms of essentialism—ones that construe essential properties as relational. I argue that if population thinking is a version of trope nominalism, then, as Mayr originally claimed, it rules out any version of essentialism about biological kinds. (shrink)

Comparing alternative scientific theories obviously is relevant to theory assessment, but are comparativists (like Laudan) correct when they also make it necessary? This paper argues that they are not. Defining rationality solely in terms of theories' comparative problem-solving strengths, comparativist philosophers of science like Laudan subscribe to what I call the irrelevance claim (IC) and the necessity claim (NC). According to IC, a scientific theory's being well or poorly confirmed is "irrelevant" to its acceptance; NC is the claim that "all (...) evaluations of research traditions and theories must be made within a comparative context," how any theory "compares with its competitors" (Laudan 1977, 21, 120). Using current competing theories (T1 and T2) of population viability assessment (PVA) for the Florida panther, the paper investigates IC/NC. In part because dominant T2 panther biologists accept IC/NC (which T1 theorists reject), the paper argues that they appear both to have accepted flawed T2 and to have contributed to flawed panther science and policy. Correcting Laudan's Comparativist Philosophy of Science (LCPS), underlying the T1-versus-T2 debate, thus may hold promise for helping resolve both the scientific and policy controversy over panther PVA. (shrink)

This book is a collection of English articles by Pan Guangdan, one of China's most distinguished sociologists and eugenicists and also a renowned expert in education. Pan is a prolific scholar, whose collected works number some fourteen volumes. Pan's daughters Pan Naigu, Pan Naimu and Pan Naihe-all scholars of anthropology and sociology-began editing their father's published works and surviving manuscripts around 1978. The collected articles, written between 1923 and 1945, are representative of Pan's insights on sociobiology, ethnology and eugenics, covering (...) topics such as Christianity, opium, domestic war and China-Japan relations. The title of the book is taken from the fascinating two-part article "Socio-biological Implications in Confucianism", which essentially reworks Confucius as a kind of "forefather" of socio-biological and eugenic thinking, showing Pan's promotion of "traditional" values. These articles, mostly published in Chinese Students' Monthly and The China Critic, offer an excellent point of entry into Pan's ideas on population and eugenics, his polemics on family and marriage, and his intellectual positioning and self-fashioning. This collection is of great reference value, allowing readers to gain an overall and in-depth understanding of the development of Pan's academic thought, and to explore the spiritual world of the scholars brought together by The China Critic who were dedicated to rebuilding the Chinese culture and bridging the West and the East. (shrink)

Tissues contain complex populations of cells. Like countries, which are comprised of mixed populations of people, tissues are not homogeneous. Gene expression studies that analyze entire populations of cells from tissues as a mixture are blind to this diversity. Thus, critical information is lost when studying samples rich in specialized but diverse cells such as tumors, iPS colonies, or brain tissue. High throughput methods are needed to address, model and understand the constitutive and stochastic differences between individual cells. Here, we (...) describe microfluidics technologies that utilize a combination of molecular biology and miniaturized labs on chips to study gene expression at the single cell level. We discuss how the characterization of the transcriptome of each cell in a sample will open a new field in gene expression analysis, population transcriptomics, that will change the academic and biomedical analysis of complex samples by defining them as quantified populations of single cells. (shrink)

Darwinian evolution is a population-level phenomenon. This paper deals with a structural population concept within the framework of generalized Darwinism, resp. within a generalized theory of evolution. According to some skeptical authors, GD is in need of a valid population concept in order to become a practicable research program. Populations are crucial and basic elements of any evolutionary explanation—biological or cultural—and have to be defined as clearly as possible. I suggest the “causal interactionist population concept”, by (...) R. Millstein for this purpose, and I will try to embed the approach into a generalized evolutionary perspective by mathematically formalizing its key definitions. Using graph-theory, populations as described in the CIPC can serve as proper clusters of evolutionary classification based on the rates of interactions between their elements. I will introduce the concept of a cohesion index as a measurement of possible population candidates within a distribution of elements. The strength of this approach lies in its applicability and interactions are relatively easy to observe. Furthermore, problems of clustering tokens via typicality, e.g. their similarity in intrinsic key characteristics, can be avoided, because CIPC is a external approach. However, some formal problems and conceptual ambiguities occur within a simple version of this CI, which will be addressed in this paper as well as some possible applications. (shrink)

The genetic revolution is well underway, with genetic research and knowledge expanding at an exponential rate. Much of the new genetics research is focused on population groups, and proponents of “population genomics” argue that such studies are necessary since genetic “variation” among human populations holds the most promise for technological innovations that can improve human health and lead to increased understanding of the origin of human populations. Population genomic research thus targets specific groups to discover variation that (...) could lead to knowledge about genetic disorders, possible cures, and the origin and migration patterns of distinctive peoples. Research on genetic differences among groups or populations, however, raises many pressing ethical and legal questions. For example, focus on biological differences of racial and ethnic groups has in the past lead to assumptions about superiority and inferiority between groups, and in practice resulted in stigmatization and discrimination. Consequently, attention on groups should raise legal and moral red flags and compel us to move cautiously in this area. Pragmatically, targeting population groups as the object of study requires the determination of the nature and scope of “population groups” for purposes of genetics research. (shrink)

At least below the level of species, biological populations are not mind‐independent objects that scientists discover. Rather, biological populations are pragmatically constructed as objects of investigation according to the aims, interests, and values that inform particular research contexts. The relations among organisms that are constitutive of population‐level phenomena (e.g., mating propensity, genealogy, and competition) occur as matters of degree and so give rise to statistically defined open‐ended biological systems. These systems are rendered discrete units to satisfy practical needs and (...) theoretical preferences associated with specific contexts of investigation. While it may be possible to defend a realist position regarding biological relations among organisms, biological populations are “made” when contextual features determine which kinds and degrees of relations to privilege over others, and so how to bound genes in space and time. Consequently, the objectivity of population‐based approaches to species genome diversity cannot rest in the mind‐independence of populations themselves. (shrink)

A consensus view appears to prevail among academics from diverse disciplines that biological races do not exist, at least in humans, and that race -concepts and race -objects are socially constructed. The consensus view has been challenged recently by Robin O. Andreasen's cladistic account of biological race. This paper argues that from a scientific viewpoint there are methodological, empirical, and conceptual problems with Andreasen's position, and that from a philosophical perspective Andreasen's adherence to rigid dichotomies between science and society, facts (...) and values, nature and culture, and the biological and the social needs to be relinquished. DNA forensics is just one field of research that reveals how race remains both idea and object for human population biologists, an indication that it is premature to accept the existence of a no- race consensus across the disciplines. DNA forensics research also demonstrates ways in which race is reified by scientists by the representation of what is cultural or social as natural or biological, and of what is dynamic, relative, and continuous as static, absolute, and discrete. The philosophical analysis of foundational concepts of human population biology such as population, race, and ethnic group is best served by foregoing traditional objectivist approaches for a critical stance that recognises the inextricability of the biological and the social. Introduction Consensus view: biological races do not exist Andreasen's defence of the biological reality of races as clades Biological permutations of race Conclusion. (shrink)

Two or more independent species lineages can fuse through an evolutionary transition to form a single lineage, such as in the case of eukaryotic cells, lichens, and coral. The fusion of two or more independent lineages requires intermediary steps of increasing selective interdependence between these lineages. We argue a precursory selective regime of such a transition can be Multilevel Selection 1 (MLS1). We propose that intraspecies MLS1 can be extended to ecological multispecies arrangements. We develop a trait group selection (MLS1) (...) model applicable to multispecies mutualistic interactions. We then explore conditions under which such a model could apply to mutualistic relationships between pollinators and plants. We propose that MLS1 could drive transitions towards higher interdependency between mutualists and stabilise obligate mutualisms in the face of invasion by cheater variants. This represents a radical extension of multilevel selection theory, applying it to the evolution of multispecies populations, and indicating new avenues for researching ecological community evolution. (shrink)

This fine collection of essays by a leading philosopher of science presents a defence of integrative pluralism as the best description for the complexity of scientific inquiry today. The tendency of some scientists to unify science by reducing all theories to a few fundamental laws of the most basic particles that populate our universe is ill-suited to the biological sciences, which study multi-component, multi-level, evolved complex systems. This integrative pluralism is the most efficient way to understand the different and complex (...) processes - historical and interactive - that generate biological phenomena. This book will be of interest to students and professionals in the philosophy of science. (shrink)