There is long-standing disagreement among systematists about how to divide biodiversity into species. Over twenty different species concepts are used to group organisms, according to criteria as diverse as morphological or molecular similarity, interbreeding and genealogical relationships. This, combined with the implications of evolutionary biology, raises the worry that either there is no single kind of species, or that species are not real. This book surveys the history of thinking about species from Aristotle to modern systematics in order to understand the origin of the problem, and advocates a solution based on the idea of the division of conceptual labor, whereby species concepts function in different ways - theoretically and operationally. It also considers related topics such as individuality and the metaphysics of evolution, and how scientific terms get their meaning. This important addition to the current debate will be essential for philosophers and historians of science, and for biologists.

Frank E. Zachos offers a comprehensive review of one of today’s most important and contentious issues in biology: the species problem. After setting the stage with key background information on the topic, the book provides a brief history of species concepts from antiquity to the Modern Synthesis, followed by a discussion of the ontological status of species with a focus on the individuality thesis and potential means of reconciling it with other philosophical approaches. More than 30 different species concepts found in the literature are presented in an annotated list, and the most important ones, including the Biological, Genetic, Evolutionary and different versions of the Phylogenetic Species Concept, are discussed in more detail. Specific questions addressed include the problem of asexual and prokaryotic species, intraspecific categories like subspecies and Evolutionarily Significant Units, and a potential solution to the species problem based on a hierarchical approach that distinguishes between ontological and operational species concepts. A full chapter is dedicated to the challenge of delimiting species by means of a discrete taxonomy in a continuous world of inherently fuzzy boundaries. Further, the book outlines the practical ramifications for ecology and evolutionary biology of how we define the species category, highlighting the danger of an apples and oranges problem if what we subsume under the same name (“species”) is in actuality a variety of different entities. A succinct summary chapter, glossary and annotated list of references round out the coverage, making the book essential reading for all biologists looking for an accessible introduction to the historical, philosophical and practical dimensions of the species problem.

Species Problems and Beyond offers a collection of up-to-date essays discussing from an interdisciplinary perspective the many ramifications of the ‘Species Problem.’ The authors represent experts in the philosophy of biology, in species-level evolutionary investigations, and in biodiversity studies and conservation. Some of the topics addressed concern the context sensitivity of the term ‘species’; species as individuals, processes, natural kinds, or as ‘operative concepts’; species delimitation in the age of Big (genomic) Data; and taxonomic inflation and its consequences for conservation strategies. The carefully edited volume will be an invaluable resource for philosophers of biology and evolutionary biologists alike. – Olivier Rieppel, Rowe Family Curator of Evolutionary Biology, Negaunee Integrative Research Center, Field Museum, USA Species, or ‘the Species Problem’, is a topic in science, in the philosophy of science, and in general philosophy. In fact, it encompasses many aspects of the same problem, and these are dealt with in this volume. Species are often thought of as fundamental units of biological matter to be used in ecology, conservation, classification, and biodiversity. The chapters in this book present opposing views on the current philosophical and conceptual issues of the Species Problem in biology. Divided into four sections, Concepts and Theories, Practice and Methods, Ranks and Trees and Names, and Metaphysics and Epistemologies, the book is authored by biologists, philosophers, and historians, many leaders in their fields. Topics include ontology of species, definitions of both species category and units, species rank, speciation issues, nomenclature, ecology, and species conservation. Species Problems and Beyond aims to clarify the contemporary issues of the Species Problem. It is ideal for use in upper-level seminars and courses in Evolutionary Biology, Philosophy of Science, Philosophy of Biology, Systematics and Taxonomy, and Phylogenetics/Cladistics, and for any scholar in these fields.

The book includes collection of theoretical papers dealing with the species problem, which is among most fundamental issues in biology. The principal topics are: consideration of the species problem from the standpoint of modern non-classical science paradigm, with emphasis on its conceptual status presuming its analysis within certain conceptual framework; evolutionary emergence of the species as discrete unit of certain level of generality; epistemological consideration of the species as a particular explanatory hypotheses, with respective revised concepts of biodiversity and conservation; considerations of evolutionary and phylogenomic species concepts as candidates for the universal one; re-appraisal of the biological species concept based on the "friend-foe" recognition system; species delimitation approach using multi-locus coalescent-based method; a re-consideration of the Darwin's species concept.

In Genes, Categories and Species, Jody Hey provides an enlightening new solution to one of biology's most ironic and perplexing puzzles. When Darwin showed that life evolves, and that it does so by natural selection, he transformed our understanding of living things. But the very question Darwin addressed-the nature of species-continues to pose an awkward conundrum for biologists. Despite enormous efforts by a great many scholars, biologists still cannot agree on how to identify species or even how to define the word "species." Genes, Categories, and Species is not like other books on the species problem, for it does not begin by asking, "What is a species?" Instead, it focuses on the very fact that biologists are stumped by species and their curious behavior in coping with that uncertainty. Faced with a persistent conundrum-and no lack of data on the subject-biologists who ponder the species problem have ceased to ask the most essential of scientific questions: "What new information do we need to resolve the problem?" This is the question that motivates this book and leads to the discoveries it reveals. The answer to the species problem lies not with the processes and patterns of biological diversity, Hey contends, but rather in the way the human mind perceives and categorizes that diversity. The promise of this book is twofold. First, it allows biologists to understand the causes of the species problem and to use this knowledge to avoid the major confusions that arise over species. Second, with its explanation of the species problem, it gives scholars and students of human nature a humbling example of how ill-suited the human mind is for certain kinds of scientific questions.

In this comprehensive work, John S. Wilkins traces the history of the idea of "species" from antiquity to today, providing a new perspective on the relationship between philosophical and biological approaches.--[book cover].

No question in theoretical biology has been more perennially controversial or perplexing than "What is a species?" Recent advances in phylogenetic theory have called into question traditional views of species and spawned many concepts that are currently competing for general acceptance. Once the subject of esoteric intellectual exercises, the "species problem" has emerged as a critically important aspect of global environmental concerns. Completion of an inventory of biodiversity, success in conservation, predictive knowledge about life on earth, management of material resources, formulation of scientifically credible public policy and law, and more depend upon our adoption of the "right" species concept. Quentin D. Wheeler and Rudolf Meier present a debate among top systematic biology theorists to consider the strengths and weaknesses of five competing concepts. Debaters include (1) Ernst Mayr (Biological Species Concept), (2) Rudolf Meier and Rainer Willmann (Hennigian species concept), (3) Brent Mishler and Edward Theriot (one version of the Phylogenetic Species Concept), (4) Quentin Wheeler and Norman Platnick (a competing version of the Phylogenetic Species Concept), and (5) E. O. Wiley and Richard Mayden (the Evolutionary Species Concept). Each author or pair of authors contributes three essays to the debate: first, a position paper with an opening argument for their respective concept of species; second, a counterpoint view of the weakness of competing concepts; and, finally, a rebuttal of the attacks made by other authors. This unique and lively debate format makes the comparative advantages and disadvantages of competing species concepts clear and accessible in a single book for the first time, bringing to light numerous controversies in phylogenetic theory, taxonomy, and philosophy of science that are important to a wide audience. Species Concepts and Phylogenetic Theory will meet a need among scientists, conservationists, policy-makers, and students of biology for an explicit, critical evaluation of a large and complex literature on species. An important reference for professionals, the book will prove especially useful in classrooms and discussion groups where students may find a concise, lucid entrée to one of the most complex questions facing science and society.