de Queiroz (1995), Griffiths (1999) and LaPorte (2004) offer a new version of essentialism called "historical essentialism". According to this version of essentialism, relations of common ancestry are essential features of biological taxa. The main type of argument for this essentialism proposed by Griffiths (1999) and LaPorte (2004) is that the dominant school of classification, cladism, defines biological taxa in terms of common ancestry. The goal of this paper is to show that this argument for historical (...) essentialism is unsatisfactory: cladism does not assume that relations of common ancestry are essential attributes of biological taxa. Therefore, historical essentialism is not justified by cladism. (shrink)

The taxa that appear in biological classifications are commonly seen as representing information about the traits of their member organisms. This paper examines in what way taxa feature in the storage and retrieval of such information. I will argue that taxa do not actually store much information about the traits of their member organisms. Rather, I want to suggest, taxa should be understood as functioning to localize organisms in the genealogical network of life on Earth. (...) Taxa store information about where organisms are localized in the network, which is important background information when it comes to establishing knowledge about organismal traits, but it is not itself information about these traits. The view of species and higher taxa that is proposed here follows from examining three problems that occur in contemporary biological systematics and are discussed here: the problem of generalization over taxa, the problem of phylogenetic inference, and the problematic nature of the Tree of Life. (shrink)

The taxa that appear in biological classifications are commonly seen as representing information about the traits of their member organisms. This paper examines in what way taxa feature in the storage and retrieval of such information. I will argue that taxa do not actually store much information about the traits of their member organisms. Rather, I want to suggest, taxa should be understood as functioning to localize organisms in the genealogical network of life on Earth. (...) Taxa store information about where organisms are localized in the network, which is important background information when it comes to establishing knowledge about organismal traits, but it is not itself information about these traits. The view of species and higher taxa that is proposed here follows from examining three problems that occur in contemporary biological systematics and are discussed here: the problem of generalization over taxa, the problem of phylogenetic inference, and the problematic nature of the Tree of Life. (shrink)

The book addresses three main issues. The first concerns the essences (natures, identities) of biological taxa, particularly species. Kripke and other metaphysicians hold that these essences are (at least partly) intrinsic, underlying, probably largely genetic properties. This view, based largely on intuitions, is dismissed by the consensus in the philosophy of biology as being incompatible with Darwinism and reflecting ignorance of biology. The book argues that the demands of biological explanation show that the metaphysicians are right. The (...) positive view of the consensus is that the essences are wholly relational: taxa must have certain histories. The book argues that there is indeed an historical component to the essence, but this component presupposes an intrinsic component. The book’s second issue concerns the essences of biological individuals. Metaphysicians have had much to say about this, again on the basis of intuitions. Many hold that an individual is essentially a member of its species. This has recently been unequivocally rejected by philosophers of biology. The book appeals to biological explanation again to argue for essential membership; furthermore, to argue for the Kripkean view that an organism’s essence is partly intrinsic and partly relational (a matter of origin). Finally, the book addresses the lively contemporary issue of whether race is biologically “real”. From the perspective developed earlier, the book argues that there are indeed racial kinds, in some sense, that are “in the realm of the biological”. These kinds also have partly historical and partly intrinsic underlying essences. (shrink)

The recognition of species proceeds by two fairly distinct phases: (1) the sorting of individuals into groups or basic taxa (‘discovery’) (2) the checking of those taxa as candidates for species-hood (‘justification’). The target here is a rational reconstruction of phase 1, beginning with a discussion of key terms. The transmission of ‘meaning’ is regarded as bimodal: definition states the intension of the term, and diagnosis provides a disjunction of criteria for recognition of its extension. The two are (...) connected by a spectrum, with purely theoretical definition at one pole and purely ‘operational’ diagnosis at the other, with the more operational elements explained by the more theoretical. The current plethora of species concepts provides a good example. Accepting the Ghiselin–Hull thesis, that a species is an individual, a basic taxon is therefore also an individual with organisms as its parts. In a generalised synchronic individual its parts are conceptually integrated by an integrating principle (IP), which consists of a relation applying within a plan or rule. Fully developed, such an IP ensures the maximisation of the information content of the individual. A diachronic individual is then the set of its component synchronic parts, and its IP is provided by near-identity in an appropriate space-time (not necessarily physical). The integration of parts of an individual is illuminated by Gasking's concept of a proper group (in this case a chain-group), whose members are related by the relation serially fitting together with, the IP completed by an appropriate plan or rule. Gasking also applied the term cluster to a proper group persisting over a substantial period of time, individuated by any member acting as focus. A basic taxon is therefore a cluster of individuals, integrated by the relation significantly taxonomically similar and the rule in character-space-time. The nature of those concepts is discussed and defended. A species will inherit certain of the attributes of the preceding basic taxon (taxa). In at least the synchronic version its parts (individuals) will resemble each other significantly, providing the intuitive applicability of ‘members of’ and ‘instances of’ a species. Also, the notion that a species’ name is given by pure ostension, via a name-bearer (holotype) is empirically incoherent: the name cannot be applied in practice without an appropriate set of diagnostic traits. (shrink)

This chapter contains sections titled: Introduction Early Species Concepts—Linnaeus Biological Species Concepts Phylogenetic Species Concepts Species Concepts and Speciation Conclusions Postscript: Counterpoint References.

In a series of articles, Rieppel (2005, Biol. Philos. 20:465–487; 2006a, Cladistics 22:186–197; 2006b, Systematist 26:5–9), Keller et al. (2003, Bot. Rev. 69:93–110), and Nixon and Carpenter (2000, Cladistics 16:298–318) criticize the philosophical foundations of the PhyloCode. They argue that species and higher taxa are not individuals, and they reject the view that taxon names are rigid designators. Furthermore, they charge supporters of the individuality thesis and rigid designator theory with assuming essentialism, committing logical inconsistencies, and offering proposals that (...) render taxonomy untestable. These charges are unsound. Such charges turn on confusions over rigid designator theory and the distinction between kinds and individuals. In addition, Rieppel’s, Keller et al.’s, and Nixon and Carpenter’s proposed alternatives are no better and have their own problems. The individuality thesis and rigid designator theory should not be quickly abandoned. [Individuals; kinds; PhyloCode; rigid designators; species; taxa; taxon names.]. (shrink)

The article defends the doctrine that Linnaean taxa, including species, have essences that are, at least partly, underlying intrinsic, mostly genetic, properties. The consensus among philosophers of biology is that such essentialism is deeply wrong, indeed incompatible with Darwinism. I argue that biological generalizations about the morphology, physiology, and behavior of species require structural explanations that must advert to these essential properties. The objection that, according to current “species concepts,” species are relational is rejected. These concepts are primarily (...) concerned with what it is for a kind to be a species and throw little light on the essentialist issue of what it is for an organism to be a member of a particular kind. Finally, the article argues that this essentialism can accommodate features of Darwinism associated with variation and change. (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)

The vision of natural kinds that is most common in the modern philosophy of biology, particularly with respect to the question whether species and other taxa are natural kinds, is based on a revision of the notion by Mill in A System of Logic. However, there was another conception that Whewell had previously captured well, which taxonomists have always employed, of kinds as being types that need not have necessary and sufficient characters and properties, or essences. These competing views (...) employ different approaches to scientific methodologies: Mill’s class-kinds are not formed by induction but by deduction, while Whewell’s type-kinds are inductive. More recently, phylogenetic kinds (clades, or monophyletic-kinds) are inductively projectible, and escape Mill’s strictures. Mill’s version represents a shift in the notions of kinds from the biological to the physical sciences. (shrink)

Biogeography is a multidisciplinary field with multiple origins in 19th century taxonomic practice. The Origins of Biogeography presents a revised history of early biogeography and investigates the split in taxonomic practice, between the classification of taxa and the classification of vegetation. This book moves beyond the traditional belief that biogeography is born from a synthesis of Darwin and Wallace and focuses on the important pioneering work of earlier practitioners such as Zimmermann, Stromeyer, de Candolle and Humboldt. Tracing the academic (...) history of biogeography over the decades and centuries, this book recounts the early schisms in phyto and zoogeography, the shedding of its bonds to taxonomy, its adoption of an ecological framework, and its beginnings at the dawn of the 20th century. This book assesses the contributions of key figures such as Zimmermann, Humboldt and Wallace, and reminds us of the forgotten influence of plant and animal geographers including Stromeyer, Prichard and de Candolle, whose early attempts at classifying animal and plant geography would inform later progress. The Origins of Biogeography is a science historiography aimed at biogeographers, who have little access to a detailed history of the practices of early plant and animal geographers. This book will also reveal how biological classification has shaped 18th and 19th century plant and animal geography and why it is relevant to the 21st biogeographer. (shrink)

Among biological kinds, the most important are species. But species, however defined, have vague boundaries, both synchronically owing to hybridization and ongoing speciation, and diachronically owing to genetic drift and genealogical continuity despite speciation. It is argued that the solution to the problems of species and their vague boundaries is to adopt a thoroughgoing nominalism in regard to all biological taxa, from species to domains. The base entities are individual organisms: populations of these compose species and higher (...) taxa. This accommodates all the important biological facts while avoiding the legacy problems of pre-evolutionary typological taxonomy, which saw species and other taxa as prior to their members. Species are however not individuals: they are spatiotemporally bounded collections, which are plural particulars. (shrink)

The foundations of systematics lie in ontology, not in subjective epistemology. Systems and their elements should be distinguished from classes; only the latter are constructed from similarities. The term classification should be restricted to ordering into classes; ordering according to systematic relations may be called systematization.The theory of organization levels portrays the real world as a hierarchy of open systems, from energy quanta to ecosystems; followingHartmann these systems as extended in time are considered the primary units of reality. Organization levels (...) should be distinguished from levels of differentiation within each organization level.Certain biological systems, such as species, continue to be misinterpreted as classes, particularly by logicians unfamiliar with modern biological theory. Replacement of Aristotelian definitions of species by “polytypic” definitions achieves nothing, because species are individual systems which can be defined from an ontological viewpoint only as wholes. The dispute whether classes are real per se or only in individuals is of no scientific importance; irrespective of which view is taken, any ordering of physical objects into classes constitutes an hypothesis about the structure of the real world.The distinction between essential and contingent characters is relevant only to classification. There are no universal rules for evaluating characters for purposes of systematization. Character statements do not form separate linear sequences. The search for “unit characters” in an absolute sense is futile. All real characters are reducible to relations and are in principle measurable, although there are limitations on the extent to which this can be presently achieved.The concept of the sexual species is fundamental to theories of biosystematics. Sexual species may be defined as lineages consisting at any given time of series of populations between which genetic exchange can occur and delimited in time by two successive processes of speciation. Linnaean nomenclature needs modification; in its traditional form it is appropriate only to non-truncated hierarchies, whereas real phylogenies form truncated hierarchies. In consequence of the distinction between systematization and classification it is concluded that, while taxa may be classified into age classes or evolutionary grades, their limits as taxa can be no different in either case. Classification into evolutionary grades remains an imprecise endeavour, since no general measure of evolutionary differentiation has been devised.The spatial and temporal extent of ecosystems, the postulated basic units of ecosystematics, remains unclarified. Nevertheless there are grounds for expecting progress in this field as the energetic relations between organisms become better understood. Biotic communities are not “abstract” classes, but systematic units. Physiognomic classification should not be confused with systematization of plant communities; both approaches contribute to an understanding of vegetational structure. (shrink)

A few philosophers of biology have recently explicitly rejected Essential Membership, the doctrine that if an individual organism belongs to a taxon, particularly a species, it does so essentially. But philosophers of biology have not addressed the broader issue, much discussed by metaphysicians on the basis of modal intuitions, of what is essential to the organism. In this paper, I address that issue from a biological basis, arguing for the Kripkean view that an organism has a partly intrinsic, partly (...) historical, essence. The arguments appeal to the demands of biological explanation and are analogous to arguments that I have given elsewhere that a taxon has a partly intrinsic, partly historical, essence. These conclusions about the essences of individuals and taxa yield an argument for Essential Membership. Finally, I cast doubt on LaPorte’s objection to that doctrine arising from the view that a species cannot survive having a daughter. (shrink)

Essentialism in philosophy is the position that things, especially kinds of things, have essences, or sets of properties, that all members of the kind must have, and the combination of which only members of the kind do, in fact, have. It is usually thought to derive from classical Greek philosophy and in particular from Aristotle’s notion of “what it is to be” something. In biology, it has been claimed that pre-evolutionary views of living kinds, or as they are sometimes called, (...) “natu-ral kinds”, are essentialist. This static view of living things presumes that no tran-sition is possible in time or form between kinds, and that variation is regarded as accidental or inessential noise rather than important information about taxa. In contrast it is held that Darwinian, and post-Darwinian, biology relies upon varia-tion as important and inevitable properties of taxa, and that taxa are not, therefore, kinds but historical individuals. Recent attempts have been made to undercut this account, and to reinstitute essentialism in biological kind terms. Others argue that essentialism has not ever been a historical reality in biology and its predecessors. In this chapter, I shall outline the many meanings of the notion of essentialism in psychology and social science as well as science, and discuss pro- and anti-essentialist views, and some recent historical revisionism. It turns out that nobody was essentialist to speak of in the sense that is antievolutionary in biology, and that much confusion rests on treating the one word, “essence” as meaning a single notion when in fact there are many. I shall also discuss the philosophical implica-tions of essentialism, and what that means one way or the other for evolutionary biology. Teaching about evolution relies upon narratives of change in the ways the living world is conceived by biologists. This is a core narrative issue. (shrink)

In the life sciences, biologists and philosophers lack a unifying concept of species—one that will reconcile intuitive demarcations of taxa with the fluidity of phenotypes found in nature. One such attempt at solving this “species problem” is known as Homeostatic Property Cluster theory (HPC), which suggests that species are not defined by singular essences, but by clusters of properties that a species tends to possess. I contend that the arbitrary nature of HPC’s kind criteria would permit a biological (...) brand of functionalism to inform species boundaries, thereby validating synthetic organisms as members of a species that do not belong. (shrink)

In the life sciences, biologists and philosophers lack a unifying concept of species—one that will reconcile intuitive demarcations of taxa with the fluidity of phenotypes found in nature. One such attempt at solving this “species problem” is known as Homeostatic Property Cluster theory, which suggests that species are not defined by singular essences, but by clusters of properties that a species tends to possess. I contend that the arbitrary nature of HPC’s kind criteria would permit a biological brand (...) of functionalism to inform species boundaries, thereby validating synthetic organisms as members of a species that do not belong. (shrink)

The received view in the philosophy of biology is that biological taxa (species and higher taxa) do not have essences. Recently, some philosophers (Boyd, Devitt, Griffiths, LaPorte, Okasha, and Wilson) have suggested new forms of biological essentialism. They argue that according to these new forms of essentialism, biological taxa do have essences. This article critically evaluates the new biological essentialism. This article’s thesis is that the costs of adopting the new biological essentialism (...) are many, yet the benefits are none, so there is no compelling reason to resurrect essentialism concerning biological taxa. (shrink)

To cite this Article: Ereshefsky, Marc , 'Foundational Issues Concerning Taxa and Taxon Names', Systematic Biology, 56:2, 295 - 301 To link to this article: DOI: 10.1080/10635150701317401 URL: http://dx.doi.org/10.1080/10635150701317401..

Biological type specimens are a particular kind of voucher specimen stored in natural history collections. Their special status and practical use are discussed in relation to the description and naming of taxonomic zoological diversity. Our current system, known as Linnaean nomenclature, is governed by the International Code of Zoological Nomenclature. The name of a species is fixed by its name-bearing type specimen, linking the scientific name of a species to the type specimen first designated for that species. The name-bearing (...) type specimen is not necessarily a typical example of the species, while establishment of the boundaries of a species requires empirical taxonomic studies. The International Code of Zoological Nomenclature allows for the naming of new species in the absence of preserved specimens. However, photos and DNA sequences should not function as primary type material, while new species should not be described and named without deposition of at least one type specimen in a collection. Philosophically, species are individuals, spatiotemporally restricted entities. Therefore, Linnaean species names are proper names, which do not define the taxon but serve as a label, providing an ostensive definition of a species. Paratypes have no name-bearing function but, nevertheless, are highly valued specimens in natural history collections. Paratypes should be restricted to those specimens originating from the same sample as the holotype. Diagnosis of a species taxon involves establishment of a connection between a Linnaean name and determination of the boundaries of the species. A first step in this process is the choice of an appropriate species concept. It is not the examination of holotypes and paratypes that necessarily provides the best estimate of the taxonomic boundaries of a species, but this is facilitated by a set of voucher specimens known as the hypodigm. Dissatisfaction with the present nomenclatural code led some researchers to propose emendations. Other taxonomists suggested abandoning Linnaean nomenclature and proposed the alternative PhyloCode, albeit that it relegates the naming of species taxa to the traditional nomenclatural codes. (shrink)

The architects of the modern synthesis banned essentialism from evolutionary theory. This rejection of essentialism was motivated by Darwin’s theory of natural selection, and the continuity of evolutionary transformation. Contemporary evolutionary biology witnesses a renaissance of essentialism in three contexts: “origin essentialism” with respect to species and supraspecific taxa, the bar coding of species on the basis of discontinuities of DNA variation between populations, and the search for laws of evolutionary developmental biology. Such “new essentialism” in contemporary biology must (...) be of a new kind that accommodates relational (extrinsic) properties as historical essences and cluster concepts of natural kinds. (shrink)

In a world of massive extinctions where not all taxa can be saved, how ought biologists to decide their preservation priorities? When biologists make recommendations regarding conservation, should their analyses be based on scientific criteria, on public or lay criteria, on economic or some other criteria? As a first step in answering this question, we examine the issue of whether biologists ought to try to save the endangered Florida panther, a well known glamour taxon. To evaluate the merits of (...) panther preservation, we examine three important arguments of biologists who are skeptical about the desirability of panther preservation. These arguments are (1) that conservation dollars ought to be spent in more efficient ways than panther preservation; (2) that biologists and conservationists ought to work to preserve species before subspecies; and (3) that biologists and conservationists ought to work to save habitats before species or subspecies. We conclude that, although all three arguments are persuasive, none of them provides convincing grounds for foregoing panther preservation in favor of other, more scientifically significant conservation efforts. Our conclusion is based, in part, on the argument that biologists ought to employ ethical, as well as scientific, rationality in setting conservation priorities and that ethical rationality may provide persuasive grounds for preserving taxa that often are not viewed by biologists as of great importance. (shrink)

Intrinsic biological essentialism (INBE) is the view that biological taxa have fixed identity conditions, conditions which consist at least in part of intrinsic properties. After a long period of near universal rejection within both philosophy of biology and theoretical biology, INBE is making a comeback. Here I attempt to support this revival by clarifying the nature of INBE, developing a new argument on its behalf, and addressing an important anti-essentialist critique.

Aristotle insists that the organic matter composing an organism depends for its being and becoming upon the living organism whose organic matter it is. An evolutionary context may at first seem to secure autonomy for an organism’s organic matter: after all, in such a context not only can organisms in divergent taxa have the same trait, but a trait can remain the same through thoroughgoing changes in its form, function, composition, and organismic context over evolutionary time. The biological (...) homology concept attempts to capture this mysterious relationship of trait sameness. However, accounts of biological homology that have dominated the contemporary scene face compelling problems—these problems, I will argue, arise from their exclusion of the organism as an explanatory locus for the being and becoming of biological traits. An evolutionary framework in fact supports an account of homology that retains these two aspects of Aristotle’s views on organic matter. (shrink)

Aristotle insists that the organic matter composing an organism depends for its being and becoming upon the living organism whose organic matter it is. An evolutionary context may at first seem to secure autonomy for an organism’s organic matter: after all, in such a context not only can organisms in divergent taxa have the same trait, but a trait can remain the same through thoroughgoing changes in its form, function, composition, and organismic context over evolutionary time. The biological (...) homology concept attempts to capture this mysterious relationship of trait sameness. However, accounts of biological homology that have dominated the contemporary scene face compelling problems—these problems, I will argue, arise from their exclusion of the organism as an explanatory locus for the being and becoming of biological traits. An evolutionary framework in fact supports an account of homology that retains these two aspects of Aristotle’s views on organic matter. (shrink)

Discussions of the theory and practice of systematics and evolutionary biology have heretofore revolved around the views of philosophers of science. I reexamine these issues from the different perspective of the philosophy of history. Just as philosophers of history distinguish between chronicle (non-interpretive or non-explanatory writing) and narrative history (interpretive or explanatory writing), I distinguish between evolutionary chronicle (cladograms, broadly construed) and narrative evolutionary history. Systematics is the discipline which estimates the evolutionary chronicle. ¶ Explanations of the events described in (...) the evolutionary chronicle are not of the covering-law type described by philosophers of science, but rather of the how-possibly, continuous series, and integrating types described by philosophers of history. Pre-evolutionary explanations of states (in contrast to chroniclar events) are still widespread in "evolutionary" biology, however, because evolutionary chronicles are in general poorly known. To the extent that chronicles are known, the narrative evolutionary histories based on them are structured like conventional historical narratives, in that they treat their central subjects as ontological individuals. This conventional treatment is incorrect. The central subjects of evolutionary narratives are clades, branched entities which have some of the properties of individuals and some of the properties of classes. Our unconscious treatment of the subjects of evolutionary narratives as individuals has been the cause of erroneous notions of progress in evolution, and of views that taxa "develop" ontogenetically in ways analogous to individual organisms. We must rewrite our narrative evolutionary histories so that they properly represent the branching nature of evolution, and we must reframe our evolutionary philosophies so that they properly reflect the historical nature of our subject. (shrink)

The value of biodiversity is usually confused with the value of biological resources, both actual and potential. A sharp distinction between biological resources and biodiversity offers a clearer insight into the value of biodiversity itself and therefore the need to preserve it. Biodiversity can be defined abstractly as the differences among biological entities. Using this definition, biodiversity can be seen more appropriately as: (a) a necessary precondition for the long term maintenance of biological resources, and therefore, (...) (b) an essential environmental condition. Three values of biodiversity are identified and arranged in a hierarchy: (1) the self-augmenting phenomenon of biodiversity maintains (2) the conditions necessary for the adaptive evolution of species and higher taxa, which in turn is necessary for providing humans with (3) a range of biological resources in the long term. Two broad policy implications emerge: increments of biodiversity should not be traded off against biological resources as if they were the same, and the conservation of biodiversity should be a constraint on the public interest, not a goal in service of the public interest. (shrink)

Talk of higher categories (ranks) like Genus and Family is ubiquitous in biology. Yet there is widespread skepticism about these categories. We can locate the source of this skepticism in the lack of “robust concepts” for these categories, robust theories of what it is to be in a certain category. A common defense of category talk is that its virtues are “just pragmatic and not theoretic”. But this strains credulity. We should suppose rather that talk of the higher categories does (...) theoretical work. What work? The paper proposes a “minimal concept” for a category, according to which the category is at least explanatory in marking out, in a rough and ready way, a level in the hierarchy of explanatory taxa. The skepticism is exaggerated. (shrink)

Defining and measuring biodiversity is an important research area in biology, with very interesting theoretical and applied aspects. Numerous definitions have been proposed, and these definitions of biodiversity influence how it is measured. From the still commonly used measure of species diversity, through higher taxon diversity, molecular measures, ecological measures and indicator taxa, these measures have as their fundamental shortcoming the lack of an explicit consideration of the evolutionary context represented by phylogenies. Attempts have been made to incorporate phylogenetic (...) considerations into measuring biodiversity, but more hypothesis‐driven research needs to be done. A specific case study is presented of how this added emphasis on phylogeny‐based biodiversity measurement can influence the way in which research is directed and hypotheses are generated. The elucidation of the relationship of biodiversity to ecosystem functioning is a very timely concern with the unarguable loss of biodiversity this planet is experiencing, whichever way biodiversity is measured. (shrink)

This paper uses two case studies to explore an interest-relative view of taxonomy and how it complements kind pluralism in biology. First, I consider the ABC island bear, which can be correctly classified into more than one species. I argue that this classificatory pluralism can be explained by reference to the range of alternative explanatory interests in biology. In the second half of the paper, I pursue an interest-relative view of classification more generally. I then apply the resultant view to (...) a second case study: whether whales are fish. I argue that this question is not one about scientific vs folk usage, as has been assumed. I also develop a new view: that Fish should be rejected as a category, both from the point of view of biological science, and from the point of view of folk taxonomy. Along the way, I use the interest-relative view to shed light on the circumstances under which higher taxa should be accepted as legitimate categories for biological science. (shrink)

In this paper I explore how the discussion about the existence of laws in biology, more specifically laws about species taxa, bears on the issue of whether species are kinds or individuals. One of the main arguments offered in favor of the view that species are individuals is that it explains the lack of laws about species taxa, since laws cannot refer to individuals. My aim in this paper is to question the premise that there are no laws (...) about species axa and consequently to show that the proposed argument fails. I will argue that even if there are no strict scientific laws about species taxa, still, scientifically interesting, law-like generalizations are made which are used for explaining phenomena and predicting properties of species members. The existence of these law-like generalizations, in turn, suggests that species are, at least prima facie, best conceived of as kinds. (shrink)

Many of the current comparisons of taxic phylogenetic and biological homology in the context of morphology focus on what are seen as categorical distinctions between the two concepts. The first, it is claimed, identifies historical patterns of conservation and variation relating taxa; the second provides a causal framework for the explanation of this conservation and variation. This leads to the conclusion that the two need not be placed in conflict and are in fact compatible, having non-competing epistemic purposes (...) or mapping the same extensions in the form of monophyletic groupings (see Roth, The biological basis of homology 1–26, 1988; Sluys, J Zool Syst Evol Res 34:145–152, 1996; Abouheif, Trends Ecol Evol 12:405–408, 1997; Brigandt, J Exp Zool 299:9–17, 2003, Biol Philos 22:709–725, 2007; Assis and Brigandt, Evol Biol 36:248–255, 2009). This article argues that moves in this direction miss the essential disagreement between these concepts as they have been developed in the context of the debate concerning the best concept for evolutionary investigation. We should rather see these concepts employing a common fundamental methodological approach to homology, but disagreeing about how to apply the methodology effectively. Both concepts employ class reasoning, which pursues homologies as units of generalization—more precisely, as sources of reliable and relevant group-bound information in the form of shared underlying causes. The dispute can be better understood by two poles that structure such reasoning: the need for a reliable basis for projections about the causal history of shared structures, and the desire to identify homologous characters with more informative and specific causal information relevant to generalizing about evolutionary processes. Judgments in favor of one or the other in turn have affected the scope or extension of these competing homology concepts. (shrink)

A standard norm of reaction (NoR) is a graphical depiction of the phenotypic value of some trait of an individual genotype in a population as a function of an environmental parameter. NoRs thus depict the phenotypic plasticity of a trait. The topological properties of NoRs for sets of different genotypes can be used to infer the presence of (non-linear) genotype-environment interactions. While it is clear that many NoRs are adaptive, it is not yet settled whether their evolutionary etiology should be (...) explained by selection on the mean phenotypic trait values in different environments or whether there are specific genes conferring plasticity. If the second alternative is true the NoR is itself an object of selection. Generalized NoRs depict plasticity at the level of populations or subspecies within a species, species within a genus, or taxa at higher levels. Historically, generalized NoRs have routinely been drawn though rarely explicitly recognized as such. Such generalized NoRs can be used to make evolutionary inferences at higher taxonomic levels in a way analagous to how standard NoRs are used for microevolutionary inferences. (shrink)

Many authors, including paleobiologists, cladists and so on, adopt a nested hierarchical viewpoint to examine the relationships among different levels of biological organization. Furthermore, species are often considered to be unique entities in functioning evolutionary processes and one of the individuals forming a nested hierarchy.I have attempted to show that such a hierarchical view is inadequate in evolutionary biology. We should define units depending on what we are trying to explain. Units that play an important role in evolution and (...) ecology do not necessarily form a nested hierarchy. Also the relationships among genealogies at different levels are not simply nested. I have attempted to distinguish the different characteristics of passages when they are used for different purposes of explanation. In my analysis, species and monophyletic taxa cannot be uniquely defined as single units that function in ecological and evolutionary processes. (shrink)

Biology is seen not merely as a privileged oppressor of women but as a co-victim of masculinist social assumptions. We see feminist critique as one of the normative controls that any scientist must perform whenever analyzing data, and we seek to demonstrate what has happened when this control has not been utilized. Narratives of fertilization and sex determination traditionally have been modeled on the cultural patterns of male/female interaction, leading to gender associations being placed on cells and their components. We (...) also find that when gender biases are controlled, new perceptions of these intracellular and extracellular relationships emerge. (shrink)

Ecologists typically invoke "law-like" generalizations, ranging over "structural" and/or "functional" kinds, in order to explain generalizations about "historical" kinds (such as biological taxa)rather than vice versa. This practice is justified, since structural and functional kinds tend to correlate better with important ecological phenomena than do historical kinds. I support these contentions with three recent case studies. In one sense, therefore, ecology is, and should be, more nomothetic, or law-oriented, than idiographic, or historically oriented. This conclusion challenges several recent (...) philosophical claims about the nature of ecological science. (shrink)

The aim of this article is to illustrate how a belief in the existence of kinds may be justified for the particular case of natural kinds: particularly noteworthy in this respect is the weight borne by scientific natural kinds (e.g., physical, chemical, and biological kinds) in (i) inductive arguments; (ii) the laws of nature; and (iii) causal explanations. It is argued that biological taxa are properly viewed as kinds as well, despite the fact that they have been (...) by some alleged to be individuals. Since it turns out that the arguments associated with the standard Kripke/Putnam semantics for natural kind terms only establish the non-descriptiveness of natural kind terms and not their rigidity, the door is open to analyze these terms as denoting traditional predicate-extensions. Finally, special issues raised by physical and chemical kinds are considered briefly, in particular impurities, isotopes and the threat of incommensurability. (shrink)

This article examines the nature of affective states across biological taxa. It argues that affect constitutes a primary form of consciousness. Creatures capable of affect are sentient of their bodily states and can behave in ways intended to maintain or restore them to a homeostatic range. After reviewing and critiquing neurobiological and philosophical theories of the evolution of consciousness, this article argues that some possible creatures are limited to self‐directed affective states, even if those creatures are capable of (...) exteroception. Such creatures enjoy solipsistic sentience: awareness of their own selves and bodily demands, but unawareness of their exogenous environments. (shrink)

Using samples from three diverse populations, we test evolutionary hypotheses regarding how people reason about the inheritance of various traits. First, we provide a framework for differentiat-ing the outputs of mechanisms that evolved for reasoning about variation within and between biological taxa and culturally evolved ethnic categories from a broader set of beliefs and categories that are the outputs of structured learning mechanisms. Second, we describe the results of a modified “switched-at-birth” vignette study that we administered among children (...) and adults in Puno, Yasawa, and adults in the United States. This protocol permits us to study perceptions of prenatal and social transmission pathways for various traits and to differentiate the latter into vertical versus horizontal cultural influence. These lines of evidence suggest that people use all three mechanisms to reason about the distribution of traits in the population. Participants at all three sites develop expectations that morphological traits are under prenatal influence, and that belief traits are more culturally influenced. On the other hand, each population holds culturally specific beliefs about the degree of social influence on non-morphological traits and about the degree of vertical transmission—with only participants in the United States expecting parents to have much social influence over their children. We reinterpret people's differentiation of trait transmission pathways in light of humans' evolutionary history as a cultural species. (shrink)

In this paper I take issue with the doctrine that organisms belong of their very essence to the natural kinds (or biological taxa, if these are not kinds) to which they belong. This view holds that any human essentially belongs to the species Homo sapiens, any feline essentially belongs to the cat family, and so on. I survey the various competing views in biological systematics. These offer different explanations for what it is that makes a member of (...) one species, family, etc. a member of that taxon. Unfortunately, none of them offers an explanation that is compatible with the essentialism in question. (shrink)