Species

1. Natural philosophy -- 2. Corpuscular pessimism -- 3. Natural history -- 4. Hypothese and analogy -- 5. Vortices, the deluge, and cohesion -- 6. Mathematics -- 7. Demonstration -- 8. Explanation -- 9. Iatrochemistyr -- 10. Generation -- 11. Species.

This article addresses some of the ways in which the development of xenotransplantation, the use of nonhuman animals as organ donors, are presented in media accounts. Although xenotransplantation raises many ethical and philosophical questions, media coverage typically minimizes these. At issue are widespread public concerns about the transgression of species boundaries, particularly those between humans and other animals. We consider how these are constructed in media narratives, and how those narratives, in turn, rely on particular scientific discourses that posit species (...) boundary crossing as unproblematic. (shrink)

Considering the official role species play in evolution, there is surprisingly little agreement among scientists or philosophers about what sort of entities species are. Many of the difficulties originate from wholly unexamined, faulty presuppositions about change and causation that characterize most thinking in modern science and philosophy. Thus, since species are essentially bound up with evolutionary change, a coherent account of their nature will require in turn a metaphysically disciplined understanding of change. This study provides both. ;This study considers the (...) known activities of species and surveys views advanced by biologists such as Mayr, Ghiselin, Simpson, Gould, and Dawkins. While competing definitions abound, all ultimately fall into one of two camps. Species are conceived either as real "individual" beings, or as class concepts. Accordingly, these camps debate species' ontological status. However, the debate is unresolvable because neither position is tenable. Actual evidence indicates species are neither individual beings such as organisms are, nor mere class concepts, such as the higher taxa are. The problem is that, wittingly or not, nearly all parties to the debate share an underlying reductionist ontology and corresponding view of causation that cannot explain the observed facts. These assumptions, which are methodological in their origin, are inadequate to explain the general phenomenon of evolutionary change, much less the role of species in it. Thus does the unique nature of species challenge the implicit metaphysical framework of science. ;Taking bearings from Aristotle's metaphysics, this study supplies a framework from which to explain species' observed nature. Of utmost importance is the principle of change, potentiality . Its recovery as a mode of being casts light on species' role in evolution and likewise on their ontological status. More generally, the principles of actuality and potentiality, together with that of function or final cause , all help portray the ontological and causal complexity of species. Recent work in the science of complexity is beginning to corroborate insights long known to Aristotle and Hegel, namely, that "complexity" and all it entails is evident in all entities when their dynamic as well as their formal natures are brought into consideration. (shrink)

The Endangered Species Act of 1973 (ESA) is America's strongest environmental law. Its citizen-suit provisionany personawards implicit intrinsic value, de facto standing, and operational legal rights (sensu Christopher D. Stone) to listed species. Accordingly, some cases had gone forward in the federal courts in the name of various listed species between 1979 (Palila v. Hawaii Dept. of Land & Natural Resources) and 2004 (Cetacean Community v. Bush), when the Ninth Circuit Court of Appeals ruled that animals could not sue in (...) their own name. Because the Supreme Court has interpreted its habitat destruction as the of a listed species, some have argued that enforcement of the ESA's critical-habitat-protection provision is a of private property without just compensation, contrary to the Fifth Amendment of the Constitution. The courts have not agreed. The ESA citizen-suit provision appears to waive federal-court standing requirements devolved from Article III of the U.S. Constitution, creating much confusion and mutually contradictory rulings. A series of cases (culminating with Bennett v. Spear) reconciles the ESA's citizen-suit provision with the particularized and concrete standing requirements devolved from Article III. (shrink)

Traditionally, species have been treated as classes or kinds in philosophical discussions of systematics and evolutionary biology. Recently a number of biologists and philosophers have proposed a drastic revision of this traditional ontological categorization. They have argued that species ought be viewed as individuals rather than as classes or natural kinds. In this paper an attempt is made to show that (a) the reasons advanced in support of this new view of species are not persuasive, (b) a reasonable explication can (...) be given of the treatment of species as classes that is consistent with current theory and practice in evolutionary biology and systematics, and (c) that once certain confusions concerning the species concept have been clarified, there are good theoretical grounds for maintaining that species are best viewed as classes or kinds. (shrink)

Traditionally, species have been treated as classes or kinds in philosophical discussions of systematics and evolutionary biology. Recently a number of biologists and philosophers have proposed a drastic revision of this traditional ontological categorization. They have argued that species ought be viewed as individuals rather than as classes or natural kinds. In this paper an attempt is made to show that (a) the reasons advanced in support of this new view of species are not persuasive, (b) a reasonable explication can (...) be given of the treatment of species as classes that is consistent with current theory and practice in evolutionary biology and systematics, and (c) that once certain confusions concerning the species concept have been clarified, there are good theoretical grounds for maintaining that species are best viewed as classes or kinds. (shrink)

John Locke intervened in two major debates in which the issue of species featured: the question of whether species designations are based on real essences or only nominal essences , and the debate over the recoinage of English currency in the 1690s, in which Locke argued for a restoration of silver depleted by widescale clipping . This article investigates Locke's position on the recoinage and considers alternative proposals in the period, including those which advocated the introduction of a ‘new species’ (...) of money in the form of credit, based on land. Locke opened the space, philosophically, for innovations in defining money, but endorsed a narrower conception of money as silver by weight alone . His rationale for doing so exposes his attachment to shared systems of measurement, intersubjective agreement and ways of stabilizing meaning by reference to external criteria . This suggests a pattern of attempting to constrain the nominalism that his system otherwise foregrounded. (shrink)

The presence of parasites in a population has an impact on mate choice and has substantial evolutionary significance. A relatively unexplored aspect of this dynamic is whether or not the presence of parasites increases the likelihood of hybridization events, which also have a significant role in ecological adaptation. One explanation of increased hybridization in some areas and not others is that stress from parasites results in selection for an increase of novel genotypes. Two swordtail species Xiphophorus birchmanni and Xiphophorus malinche (...) maintain an active hybrid zone. The patterns of hybridization are unique in that they do not match up directly with expectations. We set out to test whether or not individuals can sense, using chemical cues, whether conspecifics in their immediate vicinity have high parasite loads and also whether this has an effect on mating and association behavior toward both conspecific and hybrid mates. Our hypothesis being that females will have greater association times with hybrid/heterospecific mates if conscpecifics are heavily parasitized. We found that females exposed to parasitized males had a weaker preference for conspecific odor than those exposed to unparasitized males, both relative to a water control and relative to hybrids. The empirical investigation described above is coupled with a historical and philosophical discussion of some of the issues surrounding the acceptance and understanding of the concept of hybridization. This discussion takes as its major themes: an analysis of the role that social views have on the formation of scientific hypothesis; the lag between epochal change in the scientific community and the assimilation of the consequences into social beliefs; the survival of hierarchical and teleological thinking in our concept of species and purity; and the failures of contemporary evolutionary theory to provide satisfactory explanations about the meaning and upshot of hybridization. Two specific misconceptions about hybridization are addressed. First, that hybridization clashes with the belief in kinds/types/species having separate and pure identities. Secondly, the teleological view that reads purpose into nature and places all instances of variation on a hierarchical scale; the top and bottom of which are determined by estimated closeness to the predetermined perfection of a type. < <. (shrink)

In the philosophical works of both Ludwig Feuerback and Karl Marx , reference is made to an important technical concept usually rendered in English as 'species being' . That is, in the context of the analysis of human life and activity, both philosophers periodically speak of 'man's species being', and/or just claim that 'man' is a 'species being'. The primary objectives of the present study have been: to carry out a comprehensive analysis and elucidation of this concept of 'species being', (...) and to determine the degree of explanatory power that this concept has, both within the specific theoretical perspectives of Feuerbach and Marx, and, more generally, with reference to an adequate 'philosophical anthropology'. ;The study is divided into two general parts, plus a shorter concluding section. In Part One, the focus is on Feuerbach and his understanding of 'species being'. Included here are discussions of the influence of G. W. F. Hegel on Feuerbach, the notion of 'species being' viewed as 'human essence', the human phenomena of individuation and commonality, and the process of the 'alienation' of species being and its 'de-alienation'. Part Two centers around Marx and his understanding of 'species being'. An important part of the investigation here involves an analysis of the Hegelian and Feuerbachian influences on Marx, in terms of the extent of both his appropriation and rejection of them. Also, careful attention is paid to the ways in which the notion of 'species being' is used in Marx's earlier works, in comparison with the role that that concept plays in his later works. It is argued that there is a basic continuity between Marx's earlier and later writings, even though 'species being' was for the most part not explicity referred to in the later writings. In the Conclusion, it is argued that 'species being' is a useful theoretical construct, and that Marx's utilization of the concept is ultimately more fruitful, and less abstract, than Feuerbach's. (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)

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)

There are a number of different species concepts currently in use. The variety results from differing desiderata and practices of taxonomists, ecologists and evolutionary theorists. Recently, arguments have been presented for pluralism about species. I believe this is unsatisfactory, however, because of the central role of species in biological theory. Taking the line that species are individuals, I ask what might individuate them. In other work I have argued that dynamical systems are individuated by their cohesion. I present here a (...) version of a cohesion concept of species that accounts for the advantages of other species concepts, and is open-ended enough to accommodate additions to or changes in biological theory. On my account biological forces combine like Newtonian forces, to work on a common locus. Just as we might have an electromagnetic system, we might have an ecological species, if the dominant source of cohesion is ecology, but there is no certainty that biological species will divide up into elegant single principle types anymore than there is for physical systems. (shrink)

This chapter defends a pluralist understanding of species on which a normative species concept is viable and can support natural goodness evaluations. The central question here is thus: Since organisms are to be evaluated as members of their species, how does a proper understanding of species affect the feasibility of natural goodness evaluations? Philippa Foot has argued for a form of natural goodness evaluation in which living things are evaluated by how well fitted they are for flourishing as members of (...) their species, in ways characteristic of their species. She has further argued that assessments of moral goodness in humans are of the same evaluative form. However, natural goodness evaluations and, by extension, the natural goodness approach, do not garner justification in virtue of employing a scientifically privileged conception of species. The natural goodness approach is only justified given particular metaethical and normative commitments that are independent of naturalism, since the approach does not depend upon naturalism alone. (shrink)

Can we be realists about a general category but pluralists about concepts relating to that category? I argue that paleobiological methods of delineating species are not affected by differing species concepts, and that this underwrites an argument that species concept pluralists should be species category realists. First, the criteria by which paleobiologists delineate species are ‘indifferent’ to the species category. That is, their method for identifying species applies equally to any species concept. To identify a new species, paleobiologists show that (...) interspecies processes, such as phenotypic plasticity, sexual dimorphism, or ontogenetic diversity, are a worse explanation of the variance between specimens than intraspecies processes. As opposed to operating under a single or plurality of species concepts, then, paleobiologists use abductive inferences, which would be required regardless of any particular species concept. Second, paleobiologists are frequently interested in large-scale, long-term morphological patterns in the fossil record, and resolving the fine-grained differences which result from different species concepts is irrelevant at those scales. I argue that this claim about paleobiological practice supports what I call ‘indifference realism’ about the species category. The indifference realist argues that when legitimate investigation is indifferent to a plurality of concepts, we should be realists about the category those concepts pertain to. (shrink)

I should like to add one new motif to our discussion. But to do so I must begin with an old question, exceedingly simple-minded for so learned an audience: "Why art?" However, in accordance with the limited task I set myself, it is best to frame it in less general form:"Why has art been needed by humanity as a biological species?".

Ideias: formas, rationes e species. A Quaestio de ideis de Tomás de Aquino.

An examination of the post-Darwinian history of biological taxonomy reveals an implicit assumption that the definitions of taxon names consist of lists of organismal traits. That assumption represents a failure to grant the concept of evolution a central role in taxonomy, and it causes conflicts between traditional methods of defining taxon names and evolutionary concepts of taxa. Phylogenetic definitions of taxon names (de Queiroz and Gauthier 1990) grant the concept of common ancestry a central role in the definitions of taxon (...) names and thus constitute an important step in the development of phylogenetic taxonomy. By treating phylogenetic relationships rather than organismal traits as necessary and sufficient properties, phylogenetic definitions remove conflicts between the definitions of taxon names and evolutionary concepts of taxa. The general method of definition represented by phylogenetic definitions of clade names can be applied to the names of other kinds of composite wholes, including populations and biological species. That the names of individuals (composite wholes) can be defined in terms of necessary and sufficient properties provides the foundation for a synthesis of seemingly incompatible positions held by contemporary individualists and essentialists concerning the nature of taxa and the definitions of taxon names. (shrink)

The issue of species delimitation has long been confused with that of species conceptualization, leading to a half century of controversy concerning both the definition of the species category and methods for inferring the boundaries and numbers of species. Alternative species concepts agree in treating existence as a separately evolving metapopulation lineage as the primary defining property of the species category, but they disagree in adopting different properties acquired by lineages during the course of divergence (e.g., intrinsic reproductive isolation, diagnosability, (...) monophyly) as secondary defining properties (secondary species criteria). A unified species concept can be achieved by treating existence as a separately evolving metapopulation lineage as the only necessary property of species and the former secondary species criteria as different lines of evidence (operational criteria) relevant to assessing lineage separation. This unified concept of species has several consequences for species delimitation, including the following: First, the issues of species conceptualization and species delimitation are clearly separated; the former secondary species criteria are no longer considered relevant to species conceptualization but only to species delimitation. Second, all of the properties formerly treated as secondary species criteria are relevant to species delimitation to the extent that they provide evidence of lineage separation. Third, the presence of any one of the properties (if appropriately interpreted) is evidence for the existence of a species, though more properties and thus more lines of evidence are associated with a higher degree of corroboration. Fourth, and perhaps most significantly, a unified species concept shifts emphasis away from the traditional species criteria, encouraging biologists to develop new methods of species delimitation that are not tied to those properties. (shrink)

Advocates of cladistic parsimony methods have invoked the philosophy of Karl Popper in an attempt to argue for the superiority of those methods over phylogenetic methods based on Ronald Fisher's statistical principle of likelihood. We argue that the concept of likelihood in general, and its application to problems of phylogenetic inference in particular, are highly compatible with Popper's philosophy. Examination of Popper's writings reveals that his concept of corroboration is, in fact, based on likelihood. Moreover, because probabilistic assumptions are necessary (...) for calculating the probabilities that define Popper's corroboration, likelihood methods of phylogenetic inference—with their explicit probabilistic basis—are easily reconciled with his concept. In contrast, cladistic parsimony methods, at least as described by certain advocates of those methods, are less easily reconciled with Popper's concept of corroboration. If those methods are interpreted as lacking probabilistic assumptions, then they are incompatible with corroboration. Conversely, if parsimony methods are to be considered compatible with corroboration, then they must be interpreted as carrying implicit probabilistic assumptions. Thus, the non-probabilistic interpretation of cladistic parsimony favored by some advocates of those methods is contradicted by an attempt by the same authors to justify parsimony methods in terms of Popper's concept of corroboration. In addition to being compatible with Popperian corroboration, the likelihood approach to phylogenetic inference permits researchers to test the assumptions of their analytical methods (models) in a way that is consistent with Popper's ideas about the provisional nature of background knowledge. (shrink)

A comparison is made between the scientific receptions of three proposed new members of the hominin phylogenetic tree: the first finds of Neanderthal Man, those of Homo erectus, and those of Homo floresiensis. In each case, the leading scientists of the moment of discovery heavily debated the finds and neglected the meaning of those finds. At least it took/will take one generation before the meaning of those finds were/will be accepted.

The aptationist program includes attempts at sorting adaptations from exaptations, and therefore requires knowledge of historical changes in biological character states (traits) and their effects or functions, particularly for nonoptimal aptations. Phylogenetic inference is a key approach for historical aspects of evolutionary hypotheses, particularly testing evolutionary scenarios, and such “tree-thinking” investigation is directly relevant to the aptationist program.