At least 22 concepts of species are in use today and many of these are notably incompatible in their accounts of biological diversity. Much of the traditional turmoil embodied in the species problem ultimately derives from the packaging of inappropriate criteria for species into a single concept. This results from a traditional conflation of function of concepts with their applications, definitions with concepts, taxonomic categories with groups, and the ontological status of real species with teleological approaches to recover them. Analogous (...) to classifications of supraspecific taxa, our forging inappropriate and ambiguous information relating to theoretical and operational discussions of species ultimately results in a trade-off between convenience, accuracy, precision, and the successful recovery of natural biological diversity. Hence, none of these expectations or intentions of species or classifications is attainable through composite, and possibly discordant, concepts of biological diversity or its descent. Reviewing and evaluating the concepts of species for their theoretical and operational qualities illustrates that a monistic, primary concept of species, applicable to the various entities believed to be species, is essential. This evaluation reveals only one theoretical concept as appropriate for species, the Evolutionary Species Concept. This conceptualization functions as a primary concept and is essential in structuring our ideas and perceptions of real species in the natural world. The remaining concepts are secondary, forming a hierarchy of definitional guidelines subordinate to the primary concept, and are essential to the study of species in practice. Secondary concepts should be used as operational tools, where appropriate, across the variance in natural diversity to discover entities in accord with the primary concept. Without this theoretical and empirical structuring of concepts of species our mission to achieve reconciliation and understanding of pattern and process of the natural world will fail. (shrink)

Ideas about the natural world are intertwined with the personalities, practices, and the workplaces of scientists. The relationships between these categories are explored in the life of the taxonomist William Steel Creighton. Creighton studied taxonomy under William Morton Wheeler at Harvard University. He took the rules he learned from Wheeler out of the museum and into the field. In testing the rules against a new situation, Creighton found them wanting. He sought a new set of taxonomic principles, one he eventually (...) found in Ernst Mayr's "Systematics and the Origin of Species". Mayr's ideas tied together a number of themes running through Creighton's life: the need for a revised taxonomy, the emphasis on fieldwork, and the search for a new power center for ant taxonomy after Wheeler died. Creighton's adoption of Mayr's ideas as part of his professional identity also had very real implications for his career path: field studies required long and intensive studies, and Creighton would always be a slow worker. His method of taxonomy contrasted sharply not only with Wheeler's but also with two of his younger colleagues, William L. Brown and E. O. Wilson, who took over Wheeler's spot at Harvard in 1950. The disputes between these men over ant taxonomy involved, in addition to questions of technical interest, questions about where and how best to do taxonomy and who could speak with the most authority. Creighton's story reveals how these questions are interrelated. The story also reveals the importance of Mayr's book for changes occurring in taxonomy in the middle of the twentieth century. (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)

Despite its lack of influence in analytical philosophy, and independently of its content as a process philosophy, Whitehead's system in Process and Reality affords a valuable lesson on how to pursue revisionary systematic metaphysics. This paper argues the case generally for metaphysical revision and system, describes the structure of Whitehead's categorial scheme, endorses his idea of an ultimate which is not an entity, and outlines an alternative, “digital” ultimate or basis composed of several analytical factors. [I]n the absence of a (...) well-defined categoreal scheme of entities, issuing in a satisfactory metaphysical system, every premise in a philosophical argument is under suspicion. (shrink)

The longstanding species problem in biology has a history that suggests a solution, and that history is not the received history found in many texts written by biologists or philosophers. The notion of species as the division into subordinate groups of any generic predicate was the staple of logic from Aristotle through the middle ages until quite recently. However, the biological species concept during the same period was at first subtly and then overtly different. Unlike the logic sense, which relied (...) on definitions of the essence of both genus and species, biological species from the time of Epicurus were consistently considered to involve a reproductive element: in short, living species relied not on essential definitions, but on the generative cause, which might not be definable. I term this the generative conception of species: species were the generation by reproduction of form. This undercuts the claim that species before Darwin were essentialist, and divorces the notion of a type from that of essence. In fact, as late as the end of the nineteenth century, logicians explicitly treated biological “species” as a homonym only of logical essentialist species, and permitted considerable deviation from the type or form. At every point, species in logic were thought to be a subset, in effect, of some more general notion. I sketch a history of both philosophical and biological traditions of the species concept, before turning to the current conceptions. These are reconsidered in the light of this history, and in particular Mayr’s changing views are shown to be somewhat Whiggish, historiographically. Of the many touted biological species concepts, only one of which (Mayr’s) is called _the_ Biological Species Concept, none appears to capture all the relevant facts, intuitions, and operational requirements of biology. Cladistic conceptions, however, have much in common with the older philosophical literature, in that the natural group of cladism is the clade, or monophyletic group. After considering the Individuality Thesis, and the metaphysics of species, we see that species are the most particular terminal taxa in a clade, and that they are “defined” in terms of the particular synapomorphies, or evolved characters, that are causally responsible for keeping the lineages that organisms form distinct from one another. In this way, we can remain within the generative conception of species that has been in play for over two millennia, and yet avoid the pitfalls of prior attempts to find a universal conception of species. (shrink)

Racial constructionists, anti-naturalists, and anti-realists have challenged users of the biological race concept to provide and defend, from the perspective of biology, biological philosophy, and ethics, a biologically informed concept of race. In this paper, an ontoepistemology of biology is developed. What it is, by this, to be "biological real" and "biologically meaningful" and to represent a "biological natural division" is explained. Early 18th century race concepts are discussed in detail and are shown to be both sensible and not greatly (...) dissimilar to modern concepts. A general biological race concept (GBRC) is developed. It is explained what the GBRC does and does not entail and how this concept unifies the plethora of specific ones, past and present. Other race concepts as developed in the philosophical literature are discussed in relation to the GBRC. The sense in which races are both real and natural is explained. Racial essentialism of the relational sort is shown to be coherent. Next, the GBRC is discussed in relation to anthropological discourse. Traditional human racial classifications are defended from common criticisms: historical incoherence, arbitrariness, cluster discordance, etc. Whether or not these traditional human races could qualify as taxa subspecies – or even species – is considered. It is argued that they could qualify as taxa subspecies by liberal readings of conventional standards. Further, it is pointed out that some species concepts potentially allow certain human populations to be designated as species. It is explained why, by conventional population genetic and statistical standards, genetic differences between major human racial groups are at least moderate. Behavioral genetic differences associated with human races are discussed in general and in specific. The matter of race differences in cognitive ability is briefly considered. Finally, the race concept is defended from various criticisms. First, logical and empirical critiques are dissected. These include: biological scientific, sociological, ontological, onto-epistemological, semantic, and teleological arguments. None are found to have any merit. Second, moral-based arguments are investigated in context to a general ethical frame and are counter-critiqued. Racial inequality, racial nepotism, and the “Racial Worldview" are discussed. What is dubbed the Anti-Racial Worldview is rejected on both empirical and moral grounds. Finally, an area of future investigation – the politics of the destruction of the race concept – is pointed to. (shrink)

The genealogy-based classificatory programs of Kant and Darwin are briefly discussed for context. It is detailed how in biology there is no unambiguous term to reference infraspecific-level descent-based divisions. The term lineage population is introduced and defined for analytic purposes as one of a set of inter-fertile divisions of organisms into which members are arranged by propinquity of descent. It is argued that the lineage population concept avoids the ambiguities associated with related biological and anthropological concepts and polysemes such as (...) population, ethnicity, and race. Other terms and concepts, such as form, cline, cluster, geographic population, breeding population, genetic population, breed, species, subspecies, ancestry, geographic ancestry, biogeographic ancestry, ancestral population, ancestry population, natural division, and population lineage, are discussed in relation to this concept. It is concluded that the lineage population concept is a useful analytic tool which describes, in line with the Kantian/Darwinian perspective, an interesting class of biological variation. (shrink)

The survival enhancing propensity (SEP) account has a crucial role to play in the analysis of proper function. However, a central feature of the account, its specification of the proper environment to which functions are relativized, is seriously underdeveloped. In this paper, I argue that existent accounts of proper environment fail because they either allow too many or too few characters to count as proper functions. While SEP accounts retain their promise, they are unworkable because of their inability to specify (...) this important feature. However, I suggest that this problem can be overcome by the application of a new strategy for specifying proper environment that is grounded in the operation of natural selection and I conclude by offering a first approximation of such an account. (shrink)

Ernst Mayr''s scientific career continues strongly 70 years after he published his first scientific paper in 1923. He is primarily a naturalist and ornithologist which has influenced his basic approach in science and later in philosophy and history of science. Mayr studied at the Natural History Museum in Berlin with Professor E. Stresemann, a leader in the most progressive school of avian systematics of the time. The contracts gained through Stresemann were central to Mayr''s participation in a three year expedition (...) to New Guinea and The Solomons, and the offer of a position in the Department of Ornithology, American Museum of Natural History, beginning in 1931. At the AMNH, Mayr was able to blend the best of the academic traditions of Europe with those of North America in developing a unified research program in biodiversity embracing systematics, biogeography and nomenclature. His tasks at the AMNH were to curate and study the huge collections amassed by the Whitney South Sea Expedition plus the just purchased Rothschild collection of birds. These studies provided Mayr with the empirical foundation essential for his 1942Systematics and the Origin of Species and his subsequent theoretical work in evolutionary biology as well as all his later work in the philosophy and history of science. Without a detailed understanding of Mayr''s empirical systematic and biogeographic work, one cannot possibly comprehend fully his immense contributions to evolutionary biology and his later analyses in the philosophy and history of science. (shrink)

Four ordering systems have been used most frequently in taxonomy: (1) special purpose classifications, (2) downward classifications (identification schemes), (3) upward or grouping classifications (traditional), and (4) Hennigian phylogenetic systems. The special properties of these four systems are critically evaluated. Grouping classifications and phylogenetic systems have very different objectives: the former the documentation of similarity and closeness of relationship, the latter of phylogeny. Both are legitimate ordering systems.

A given explanatory theory T falls into circular reasoning if the only way to determine its explanandum is through the application of T. To find an underlying theory T′ that determines T′s explanandum helps us save T from this accusation of circularity. We follow the structuralist view of theories in presenting and dealing with this issue, by applying it to particular theories. More specifically, we focus on the relationship between the Darwinian theory of common ancestry and the determination of homologies.

Numerous concepts exist for biological species. This diversity of ideas derives from a number of sources ranging from investigative study of particular taxa and character sets to philosophical aptitude and world view to operationalism and nomenclatorial rules. While usually viewed as counterproductive, in reality these varied concepts can greatly enhance our efforts to discover and understand biological diversity. Moreover, this continued "turf war" and dilemma over species can be resolved if the various concepts are viewed in a hierarchical system and (...) each evaluated for its inherent level of consilience. Under this paradigm a theoretically appropriate, highly consilient concept of species capable of colligating the abundant types of species diversity offers the best guidance for developing and employing secondary operational concepts for identifying diversity. Of all the concepts currently recognized, only the non-operational Evolutionary Species Concept corresponds to the requisite parameters and, therefore, should serve as the theoretical concept appropriate for the category Species. As operational concepts, the remaining ideas have been incompatible with one another in their ability to encompass species diversity because each has restrictive criteria as to what qualifies as a species. However, the operational concepts can complement one another and do serve a vital role under the Evolutionary Species Concept as fundamental tools necessary for discovering diversity compatible with the primary theoretical concept. Thus, the proposed hierarchical system of primary and secondary concepts promises both the most productive framework for mutual respect for varied concepts and the most efficient and effective means for revealing species diversity. (shrink)