What is scientific progress? This paper advances an interpretation of this question, and an account that serves to answer it. Roughly, the question is here understood to concern what type of cognitive change with respect to a topic X constitutes a scientific improvement with respect to X. The answer explored in the paper is that the requisite type of cognitive change occurs when scientific results are made publicly available so as to make it possible for anyone to increase their understanding (...) of X. This account is briefly compared to two rival accounts of scientific progress, based respectively on increasing truthlikeness and accumulating knowledge, and is argued to be preferable to both. (shrink)

We attempt to defend the species-as-individuals hypothesis by examining the logical role played by the binomials (e.g., "Homo sapiens," "Pinus ponderosa") in biological discourse about species. Those who contend that the binomials can be properly understood as functioning in biological theory as singular terms opt for an objectual account of species and view species as individuals. Those who contend that the binomials can in principle be eliminated from biological theory in favor of predicate expressions opt for a predicative account of (...) species and view species as kinds. We contend that biologists' talk about species is talk about species as individuals, and we conclude that the most plausible account of species is an objectual account. (shrink)

Here, I consider the recent application of phylogenetic methods in historical linguistics. After a preliminary survey of one such method, i.e. cladistic parsimony, I respond to two common criticisms of cultural phylogenies: that cultural artifacts cannot be modeled as tree-like because of borrowing across lineages, and that the mechanism of cultural change differs radically from that of biological evolution. I argue that while perhaps remains true for certain cultural artifacts, the nature of language may be such as to side-step this (...) objection. Moreover, I explore the possibility that cladistic parsimony can be justified even if is true by appealing to the inference pattern known among philosophers as ‘Inference to the Best Explanation’. (shrink)

Comparative analysis of the behavior of modern primates, in conjunction with an accurate phylogenetic tree of relatedness, has the power to chart the early history of human cognitive evolution. Adaptive cognitive changes along this path occurred, it is believed, in response to various forms of complexity; to some extent, theories that relate particular challenges to cognitive adaptations can also be tested against comparative data on primate ecology and behavior. This paper explains the procedures by which data are employed, and uses (...) the best currently available evidence to derive a proposal for some of the stages through which human cognition evolved, before the last common ancestor with a nonhuman, and the reasons that cognitive adaptations were favored in primate evolution. (shrink)

There is no question that the constituents of cells and organisms are joined together by the part-whole relation. Genes are part of cells, and cells are part of organisms. Species taxa, however, have traditionally been conceived of, not as wholes with parts, but as classes with members. But why does the relation change abruptly from part-whole to class-membership above the level of organisms? Ghiselin, Hull and others have argued that it doesn't. Cells and organisms are cohesive mereological sums, and since (...) species taxa are like cells and organisms in the relevant respects, they, too, are cohesive mereological sums. I provide further reasons in support of the thesis that species are mereological sums. I argue, moreover, that the advocate of this thesis is committed to a form of pluralism with respect to the species concept. (shrink)

Proponents of two axioms of biological evolutionary theory have attempted to find justification by reference to nonequilibrium thermodynamics. One states that biological systems and their evolutionary diversification are physically improbable states and transitions, resulting from a selective process; the other asserts that there is an historically constrained inherent directionality in evolutionary dynamics, independent of natural selection, which exerts a self-organizing influence. The first, the Axiom of Improbability, is shown to be nonhistorical and thus, for a theory of change through time, (...) acausal. Its perception of the improbability of living states is at least partially an artifact of closed system thinking. The second, the Axiom of Historically Determined Inherent Directionality, is supported evidentially and has an explicit historical component. Historically constrained dynamic populations are inherently nonequilibrium systems. It is argued that living, evolving systems, when considered to be historically constrained nonequilibrium systems, do not appear improbable at all. Thus, the two axioms are not compatible. Instead, the Axiom of Improbability is considered to result from an unjustified attempt to extend the contingent proximal actions of natural selection into the area of historical, causal explanations. It is thus denied axiomatic status, and the effects of natural selection are subsumed as an additional level of constraint in an evolutionary theory derived from the Axiom of Historically Determined Inherent Directionality. (shrink)

Quinn offered seven definitions of “cladist” and discussed the context in which they are used in relation to historical and current debates in systematics. As a member of her study taxon, I offer some contextual color commentary, clarifications on the views of “pattern cladists” regarding monophyly, ancestors, synapomorphy and other concepts, a definition of “syncretist”, and some thoughts on cladistics and philosophy in the twenty first century.

Integrating concepts of maintenance and of origins is essential to explaining biological diversity. The unified theory of evolution attempts to find a common theme linking production rules inherent in biological systems, explaining the origin of biological order as a manifestation of the flow of energy and the flow of information on various spatial and temporal scales, with the recognition that natural selection is an evolutionarily relevant process. Biological systems persist in space and time by transfor ming energy from one state (...) to another in a manner that generates structures which allows the system to continue to persist. Two classes of energetic transformations allow this; heat-generating transformations, resulting in a net loss of energy from the system, and conservative transformations, changing unusable energy into states that can be stored and used subsequently. All conservative transformations in biological systems are coupled with heat-generating transformations; hence, inherent biological production, or genealogical proesses, is positively entropic. There is a self-organizing phenomenology common to genealogical phenomena, which imparts an arrow of time to biological systems. Natural selection, which by itself is time-reversible, contributes to the organization of the self-organized genealogical trajectories. The interplay of genealogical (diversity-promoting) and selective (diversity-limiting) processes produces biological order to which the primary contribution is genealogical history. Dynamic changes occuring on times scales shorter than speciation rates are microevolutionary; those occuring on time scales longer than speciation rates are macroevolutionary. Macroevolutionary processes are neither redicible to, nor autonomous from, microevolutionary processes. (shrink)

Several species concepts are generally discussed and evaluated. Then the new definition, the pheno-genetic species concept, is developed; it reads: a species is the largest possible, regional evolutionary unit of pheno-genetically equal (in the typical, specific characters), identically reproducing demes. It is separated from sympatric species by a reproductive isolation that guarantees a unique evolution, an evolution different from that of other species and sufficiently uninfluenced, and that is accompanied by another distinctive pheno-genetic gap. It is separated from allopatric species (...) by a distinctive pheno-genetic gap that - in the case of missing reproductive isolation in bisexual forms — allows the conclusion that such an isolation would have developed, if the species had been sympatric with the allopatric species. This definition is applied to several situations of evolution. The effects of the concepts on the classification of lizards are demonstrated by examples. (shrink)

Homology is a natural kind term and a precise account of what homology is has to come out of theories about the role of homologues in evolution and development. Definitions of homology are discussed with respect to the question as to whether they are able to give a non-circular account of the correspondence or sameness referred to by homology. It is argued that standard accounts tie homology to operational criteria or specific research projects, but are not yet able to offer (...) a concept of homology that does not presuppose a version of homology or a comparable notion of sameness. This is the case for phylogenetic definitions that trace structures back to the common ancestor as well as for developmental approaches such as Wagner's biological homology concept. In contrast, molecular homology is able to offer a definition of homology in genes and proteins that explicates homology by reference to more basic notions. Molecular correspondence originates by means of specific features of causal processes. It is speculated that further understanding of morphogenesis might enable biologists to give a theoretically deeper definition of homology along similar lines: an account which makes reference to the concrete mechanisms that operate in organisms. (shrink)

Several authors have argued that higher taxa are monophyletic homeostatic property cluster natural kinds. On the traditional definition of monophyly, this will not work: the emergence of taxon-defining homeostatic property clusters would not always correspond to unique speciation events. An alternative conception of monophyly is developed and advocated, which can accommodate the homeostatic property cluster proposal. Recent work in philosophy of science shows that it meets appropriate standards of objectivity and precision.

This thematic issue addresses questions of constraints on the evolution of form—physical, biological, and technical. Here, form is defined as an embodiment of a specific structure, which can be hierarchically different yet emerge from the same processes. The focus of this contribution is about how developmental biology and paleontology can be better integrated and compared in order to produce hypotheses about the evolution of form. The constraints on current EvoDevo research stem from the disconnect in the focus of study for (...) developmental geneticists and evolutionary morphologists; the former being interested in early developmental events at a molecular level in a model animal, the latter in late developmental events or comparison between adult forms, at a structural level in non-model animals. In order to truly integrate information from both fields in our understanding of evolutionary processes, morphology needs to be reintegrated in the study of gene expression, and its time frame needs to be extended beyond early developmental stages. Gene expression in non-model organisms also needs to be studied in order to gain perspective into primitive patterning at evolutionary nodes. Hypotheses formed by the comparison of expression patterns and morphologies seen in extant species can then be tested against forms found in the fossil record, coming closer to understanding the mechanisms underlying evolution. (shrink)

-/- Because species names play an important role in scientific communication, it is more important that species be understood to be taxa than that they be equated with functional ecological or evolutionary entities. Although most biologists would agree that taxa are composed of organisms that share a unique common history, 2 major challenges remain in developing a species-as-taxa concept. First, grouping: in the face of genealogical discordance at all levels in the taxonomic hierarchy, how can we understand the nature of (...) taxa? Second, ranking: what criteria should be used to designate certain taxa in a nested series as being species? The grouping problem can be solved by viewing taxa as exclusive groups of organisms— sets of organisms that form a clade for a plurality of the genome (more than any conflicting set). However, no single objective criterion of species rank can be proposed. Instead, the species rank should be assigned by practitioners based on the semisubjective application of a set of species-ranking criteria. Although these criteria can be designed to yield species taxa that approximately match the ecological, evolutionary, and morphological entities that taxonomists have traditionally associated with the species rank, such a correspondence cannot be enforced without undermining the assumption that species are taxa. The challenge and art of monography is to use genealogical and other kinds of data to assign all organisms to one and only one species-ranked taxon. Various implications of the species-as-ranked-taxa view are discussed, including the synchronic nature of taxa, fossil species, the treatment of hybrids, and species nomenclature. I conclude that, although challenges remain, adopting the view that species are ranked taxa will facilitate a much-needed revolution in taxonomy that will allow it to better serve the biodiversity informatic needs of the 21st century. (shrink)

The authors analyze Takhtajan's system of classification of the Angiosperms in relation to the principles of evolutionary and cladistic systematics. It is shown that Takhtajan belongs to the evolutionary school: he identifies the ancestors of some taxa, he accepts polytomous branching and he groups taxa on the basis of primitive as well as derived character states. Takhtajan's notion of weighted similarity does not appear to be based on objective criteria, when determining the weight and evolutionary status of characters.After a summary (...) of the modifications brought out by Takhtajan in his 1980 version, the weak and strong points of evolutionary systems as a whole are emphasized. In these, the delimitation of taxa and their filiation are difficult to refute since they do not rely on precise criteria, which would ensure continuity and uniformity within a given system. However, these systems have some flexibility, which allows them to incorporate readily new information, a feature unfortunately missing in cladistic classifications. In fact, while it does have weaknesses from a theoretical point of view, the system of Takhtajan gives us an idea of flowering plants phylogeny that appears to be one of the most complete at the present time from both analytical and synthetic standpoints. (shrink)

The circumscription of taxa and classification of organisms are fundamental tasks in the systematization of biological diversity. Their success depends on a unified idea concerning the species concept, evolution, and taxonomy; paradoxically, however, it requires a complete distinction between taxa and evolutionary units. To justify this view, I discuss these three topics of systematics. Species concepts are examined, and I propose a redefinition for the Taxonomic Species Concept based on nomenclatural properties, in which species are classes conventionally represented by a (...) binomial. Speciation is subsequently discussed, to demonstrate that concepts on the evolutionary process are damaged when species are considered as evolutionary units. Speciation should be considered a transition among patterns of a population and, consequently, always a sympatric process. This view contrasts with the majority of speciation models, which analyze cladogeneses and classify speciation geographically, usually considering allopatry the essential condition for the differentiation process. Finally, taxonomy is considered, to show that the equivalence between evolutionary and taxonomic units may also damage the practice of biological systematization. Principles and rules of nomenclature and classification should offer freedom to accommodate divergent opinions about systematics and to incorporate the evolution of knowledge; therefore, they should remain independent of biological theories. (shrink)

Race was once thought to be a real biological kind. Today the dominant view is that objective biological races don't exist. I challenge the trend to reject the biological reality of race by arguing that cladism (a school of classification that individuates taxa by appeal to common ancestry) provides a new way to define race biologically. I also reconcile the proposed biological conception with constructivist theories about race. Most constructivists assume that biological realism and social constructivism are incompatible views about (...) race; I argue that the two conceptions can be compatible. (shrink)

These preprints were automatically compiled into a PDF from the collection of papers deposited in PhilSci-Archive in conjunction with the PSA 2018.

A number of authors argue that while species are evolutionary units, individuals and real entities, higher taxa are not. I argue that drawing the divide between species and higher taxa along such lines has not been successful. Common conceptions of evolutionary units either include or exclude both types of taxa. Most species, like all higher taxa, are not individuals, but historical entities. Furthermore, higher taxa are neither more nor less real than species. None of this implies that there is no (...) distinction between species and higher taxa; the point is that such a distinction is more subtle than many authors have claimed. (shrink)

Some plausibly necessary a posteriori theoretical claims include ‘water is H 2 O’, ‘gold is the element with atomic number 79’, and ‘cats are animals’. In this paper I challenge the necessity of the third claim. I argue that there are possible worlds in which cats exist, but are not animals. Under any of the species concepts currently accepted in biology, organisms do not belong essentially to their species. This is equally true of their ancestors. In phylogenetic systematics, monophyletic clades (...) such as the animal kingdom are composed of an ancestral stem species and all of its descendants. If the stem species had not existed, neither would the clade. Thus it could have been the case that all the organisms which actually belong to the animal kingdom might have existed yet not have been animals. (shrink)

The allegedly alternative theories of Phyletic Gradualism and Punctuated Equilibria are examined as regards the nature of their differences. The explanatory value of both models is determined by establishing their actual connection with reality. It is concluded that they are to be considered complementary rather than mutually exclusive at all levels of infraspecific, specific, and supraspecific evolution. So, in order to be described comprehensively, the pathways of evolution require at least two distinct models, each based on a discrete range of (...) real phenomena. [Phyletic Gradualism; Punctuated Equilibria; evolutionary theories; divergence models; additive speciation; microevolution; macroevolution; anagenesis.]. (shrink)

Classifying is a fundamental operation in the acquisition of knowledge. Taxonomic theory can help students of cognition, evolutionary psychology, ethology, anatomy, and sociobiology to avoid serious mistakes, both practical and theoretical. More positively, it helps in generating hypotheses useful to a wide range of disciplines. Composite wholes, such as species and societies, are “individuals” in the logical sense, and should not be treated as if they were classes. A group of analogous features is a natural kind, but a group of (...) homologous features is not. Imposing hypotheses justified only on the basis of nominalist, realist, phenomenalist, or conceptualist metaphysics upon the neurophysiology of organisms or upon the causes of behavior exemplifies the “psychologist's fallacy” of William James. Levels should be distinguished from their members and from classes of levels, and the ontological status of entities ranked at levels should be made clear. It is important not to confuse such categories as substance and process with one another. Several genetical terms, such as “gene” and chromosome,” are even more equivocal than has been realized. Discussions about units of selection, behavior, and thinking suffer from the ambiguity of a “unit of” an entity. An important source of misunderstanding about natural selection is the habit of treating it as an “agent”: in an important sense, natural selection does not “act” at all. (shrink)

I defend a view of the species category, pluralistic realism, which is designed to do justice to the insights of many different groups of systematists. After arguing that species are sets and not individuals, I proceed to outline briefly some defects of the biological species concept. I draw the general moral that similar shortcomings arise for other popular views of the nature of species. These shortcomings arise because the legitimate interests of biology are diverse, and these diverse interests are reflected (...) in different legitimate approaches to the classification of organisms. In the final section, I show briefly how the pluralistic approach can help to illuminate some areas of biological and philosophical dispute. (shrink)

This paper addresses the general problem of how to rationally choose an algorithm for phylogenetic inference. Specifically, the controversy between maximum likelihood (ML) and maximum parsimony (MP) perspectives is reframed within the philosophical issue of theory choice. A Kuhnian approach in which rationality is bounded and value-laden is offered and construed through the notion of a Style of Modeling. A Style is divided into four stages: collecting remnant models, constructing models of taxonomical identity, implementing modeling algorithms, and finally inferring and (...) confirming evolutionary trees or cladograms. The identification and investigation of styles is useful for exploring sociological and epistemological issues such as individuating scientific communities and assessing the rationality of algorithm choice. Regarding the last point, this paper suggests that the values motivating ML and MP perspectives are justified but only contextually; these algorithms also have normative force because they can be therapeutic by allowing us to rationally choose among several competing trees, nonetheless this force is limited and cannot be used in order to decide the controversy tout court. (shrink)

This paper addresses the general problem of how to rationally choose an algorithm for phylogenetic inference. Specifically, the controversy between maximum likelihood (ML) and maximum parsimony (MP) perspectives is reframed within the philosophical issue of theory choice. A Kuhnian approach in which rationality is bounded and value-laden is offered and construed through the notion of a Style of Modeling. A Style is divided into four stages: collecting remnant models, constructing models of taxonomical identity, implementing modeling algorithms, and finally inferring and (...) confirming evolutionary trees or cladograms. The identification and investigation of styles is useful for exploring sociological and epistemological issues such as individuating scientific communities and assessing the rationality of algorithm choice. Regarding the last point, this paper suggests that the values motivating ML and MP perspectives are justified but only contextually; these algorithms also have normative force because they can be therapeutic by allowing us to rationally choose among several competing trees, nonetheless this force is limited and cannot be used in order to decide the controversy tout court. (shrink)

The formal definition of species as explanatory hypotheses presented by Fitzhugh is emended. A species is an explanatory account of the occurrences of the same character among gonochoristic or cross-fertilizing hermaphroditic individuals by way of character origin and subsequent fixation during tokogeny. In addition to species, biological systematics also employs hypotheses that are ontogenetic, tokogenetic, intraspecific, and phylogenetic, each of which provides explanatory hypotheses for distinctly different classes of causal questions. It is suggested that species hypotheses can not be applied (...) to organisms with obligate asexual, parthenogenetic, and self-fertilizing modes of reproduction. Hypotheses explaining shared characters among such organisms are, instead, strictly phylogenetic. Several implications of this emended definition are examined, especially the relations between species, intraspecific, and phylogenetic hypotheses, as well as the limitations of species names to be applied to temporally different characters within populations. (shrink)

Much philosophical progress has been made in elucidating the idea of evolutionary contingency in a recent re-burgeoning of the debate. However, additional progress has been impaired on three fronts. The first relates to its characterisation: the under-specification of various contingency claims has made it difficult to conceptually pinpoint the scope to which ‘contingency’ allegedly extends, as well as which biological forms are in contention. That is—there appears to be no systematic means with which to fully specify contingency claims which has (...) led to a tendency for authors to talk past each other. Secondly, on the matter of evidence, recent research has focused on the evidential import of convergent evolution which is taken to disconfirm the evolutionary contingency thesis. However, there has been a neglect of convergent evolution’s converse: ‘evolutionary idiosyncrasies’ or the singular evolution of certain forms, which I argue is evidentially supportive of evolutionary contingency. Thirdly, evolutionary contingency has often been claimed to vary in degrees and that the debate, itself, is a matter of ‘relative significance’. However, there has been no formal method of evaluating the strength of contingency and its relative significance in a particular domain. In this paper, I address all three issues by proposing a systematic means of fully specifying contingency theses with the concept of the modal range. Secondly, I propose an account of evolutionary idiosyncrasies, investigate the explanations for their occurrences, and, subsequently, spell out their significance with respect to the evolutionary contingency thesis. Finally, having been equipped with the evidential counterpart to convergent evolution, I shall sketch a likelihood framework for evaluating, precisely on the basis of a sequence of opposing data, the strength and relative significance of evolutionary contingency in a particular domain. With this in hand, the relative observations of idiosyncrasies and convergences can be informative of the strength and relative significance of contingency in any particular domain. (shrink)

Analytical categories of scientific cultures have typically been used both exclusively and universally. For instance, when styles of scientific research are employed in attempts to understand and narrate science, styles alone are usually employed. This article is a thought experiment in interweaving categories. What would happen if rather than employ a single category, we instead investigated several categories simultaneously? What would we learn about the practices and theories, the agents and materials, and the political-technological impact of science if we analyzed (...) and applied styles, paradigms, and models simultaneously? I address these questions in general and for a specific case study: a brief history of systematics. (shrink)

The dangers of character reification for cladistic inference are explored. The identification and analysis of characters always involves theory-laden abstraction—there is no theory-free “view from nowhere.” Given theory-ladenness, and given a real world with actual objects and processes, how can we separate robustly real biological characters from uncritically reified characters? One way to avoid reification is through the employment of objectivity criteria that give us good methods for identifying robust primary homology statements. I identify six such criteria and explore each (...) with examples. Ultimately, it is important to minimize character reification, because poor character analysis leads to dismal cladograms, even when proper phylogenetic analysis is employed. Given the deep and systemic problems associated with character reification, it is ironic that philosophers have focused almost entirely on phylogenetic analysis and neglected character analysis. (shrink)

The development of comparative biology has been of interest to philosophers and historians. Particular attention has been placed on the ‘war’ of the 1970s and 1980s, the apparent dispute among those who preferred this or that methodology. In this contribution we examine the history of comparative biology from the perspective of fundamentals rather than methodologies. Our examination is framed within the artificial—natural classification dichotomy, a viewpoint currently lost from view but worth resurrecting.

Cladistic analyses are based on the distinction between primitive and derived character states (hypotheses of the polarity of evolutionary transformations) and a complete reliance on only derived character state distributions as bona fide evidence of holophyletic assemblages of taxa. The cladistic premise that only derived character state distributions provide evidence of holophyly is reconsidered and shown to be both unjustified and inconsistent with the desire or methodological prescription of using all the available evidence. Cladistic techniques are here viewed primarily as (...) methods for the ordering of character states so that they may be differentially weighted. The problem of assigning realistic differential weight to primitive and derived character state distributions is briefly discussed. One possible use of primitive character state distributions as evidence of holophyly that is largely free of the problem of weight is proposed. This application is illustrated with an example from the caecilian amphibians (Amphibia: Gymnophiona). (shrink)

The biological species (biospecies) concept applies only to sexually reproducing species, which means that until sexual reproduction evolved, there were no biospecies. On the universal tree of life, biospecies concepts therefore apply only to a relatively small number of clades, notably plants andanimals. I argue that it is useful to treat the various ways of being a species (species modes) as traits of clades. By extension from biospecies to the other concepts intended to capture the natural realities of what keeps (...) taxa distinct, we can treat other modes as traits also, and so come to understand that theplurality of species concepts reflects the biological realities of monophyletic groups.We should expect that specialists in different organisms will tend to favour those concepts that best represent the intrinsic mechanisms that keep taxa distinct in their clades. I will address the question whether modes ofreproduction such as asexual and sexual reproduction are natural classes, given that they are paraphyletic in most clades. (shrink)

Wilkinson (1991) suggests that the problems of polarity decisions and homoplasy in a cladistic analysis may be solved if cladists simply accept plesiomorphy as a reliable indicator of monophyly. Here we argue that: (1) Wilkinson's argument is based on misapprehension of synapomorphy and the problem of homoplasy; (2) His proposed methodology fails to consider the full ramifications of rooting, polarity, and parsimony; and (3) His method does not solve the problems he raises. We demonstrate the limitations of this methodology by (...) using Wilkinson's practical example. We find no justification for the assertion that plesiomorphy may reliably delimit monophyly and recommend against Wilkinson's suggested methodological revisions. (shrink)

Despite the amount of work that has been produced on the subject over the years, the ‘transformation of cladistics’ is still a misunderstood episode in the history of comparative biology. Here, I analyze two outstanding, highly contrasting historiographic accounts on the matter, under the perspective of an influential dichotomy in the philosophy of science: the opposition between Scientific Realism and Empiricism. Placing special emphasis on the notion of ‘causal grounding’ of morphological characters in modern developmental biology’s theories, I arrive at (...) the conclusion that a ‘new transformation of cladistics’ is philosophically plausible. This ‘reformed’ understanding of ‘pattern cladistics’ entails retaining the interpretation of cladograms as ‘schemes of synapomorphies’, but in association to construing cladogram nodes as ‘developmental-genetic taxic homologies’, instead of ‘standard Darwinian ancestors’. The reinterpretation of pattern cladistics presented here additionally proposes to take Bas Van Fraassen’s ‘constructive empiricism’ as a philosophical stance that could properly support such analysis of developmental-genetic data for systematic purposes. The latter suggestion is justified through a reappraisal of previous ideas developed by prominent pattern cladists , which concerned a scientifically efficient ‘observable/non-observable distinction’ linked to the conceptual pair ‘ontogeny and phylogeny’. Finally, I argue that a robust articulation of Antirealist alternatives in systematics may provide a rational basis for its disciplinary separation from evolutionary biology, as well as for a critical reconsideration of the proper role of certain Scientific Realist positions, currently popular in comparative biology. (shrink)

A natural starting place for developing a phylogenetic species concept is to examine monophyletic groups of organisms. Proponents of “the” Phylogenetic Species Concept fall into one of two camps. The first camp denies that species even could be monophyletic and groups organisms using character traits. The second groups organisms using common ancestry and requires that species must be monophyletic. I argue that neither view is entirely correct. While monophyletic groups of organisms exist, they should not be equated with species. Instead, (...) species must meet the more restrictive criterion of being genealogically exclusive groups where the members are more closely related to each other than to anything outside the group. I carefully spell out different versions of what this might mean and arrive at a working definition of exclusivity that forms groups that can function within phylogenetic theory. I conclude by arguing that while a phylogenetic species concept must use exclusivity as a grouping criterion, a variety of ranking criteria are consistent with the requirement that species can be placed on phylogenetic trees. (shrink)

The concept of biological mimicry is viewed as a ‘process of life’ theory rather than a ‘process of change’ theory—regardless of the historical interest and heuristic value of the subject for the study of evolution. Mimicry is a dynamic ecological system reflecting the possibilities for mutualism and parasitism created by a pre-established bipartite signal-based relationship between two organisms – a potential model and its signal receiver (potential operator). In a mimicry system agency and perception play essential, interconnected roles. Mimicry thus (...) describes emergent biologically meaningful relationships based on synergy, and is not an object-based theory. Biosemiotics offers a particularly valuable discipline for analysing the dynamics and nuances of mimicry systems, and can thus pave the way for a better and more complete understanding of how mimicry has evolved in the past, and how it might evolve in the future—presented here with special reference to the need for an integrated, ‘third way of evolution’ approach to biological relativity. A revised definition of mimicry is proposed. (shrink)

Pluralist and eliminativist positions have proliferated within both science and philosophy of science in recent decades. This paper asks the question why this shift of thinking has occurred, and where it is leading us. We provide an explanation which, if correct, entails that we should expect pluralism and eliminativism to transform other debates currently unaffected, and for good reasons. We then consider the question under what circumstances eliminativism will be appropriate, arguing that it depends not only on the term in (...) question, but also on the context of discussion and details of the debate at hand. The resultant selective eliminativism is an appealing compromise for various ‘pluralists’ and ‘eliminativists’ who are currently locking horns. (shrink)