What Is Biodiversity? is a theoretical and conceptual exploration of the biological world and how diversity is valued. Maclaurin and Sterelny explore not only the origins of the concept of biodiversity, but also how that concept has been shaped by ecology and more recently by conservation biology. They explain the different types of biodiversity important in evolutionary theory, developmental biology, ecology, morphology and taxonomy and conclude that biological heritage is rich in not just one biodiversity but many. Maclaurin and Sterelny (...) also explore the case for the conservation of these biodiversities using option value theory, a tool borrowed from economics. (shrink)

This book explores the epistemological and ethical issues at the foundations of environmental philosophy, emphasising the conservation of biodiversity. Sahota Sarkar criticises attempts to attribute intrinsic value to nature and defends an anthropocentric position on biodiversity conservation based on an untraditional concept of transformative value. Unlike other studies in the field of environmental philosophy, this book is as much concerned with epistemological issues as with environmental ethics. It covers a broad range of topics, including problems of explanation and prediction in (...) traditional ecology and how individual-based models and Geographic Information Systems technology is transforming ecology. Introducing a brief history of conservation biology, Sarkar analyses the consensus framework for conservation planning through adaptive management. He concludes with a discussion of directions for theoretical research in conservation biology and environmental philosophy. (shrink)

This paper examines the species problem in microbiology and its implications for the species problem more generally. Given the different meanings of ‘species’ in microbiology, the use of ‘species’ in biology is more multifarious and problematic than commonly recognized. So much so, that recent work in microbial systematics casts doubt on the existence of a prokaryote species category in nature. It also casts doubt on the existence of a general species category for all of life (one that includes both prokaryotes (...) and eukaryotes). Prokaryote biology also undermines recent attempts to save the species category, such as the suggestion that species are metapopulation lineages and the idea that ‘species’ is a family resemblance concept. (shrink)

Recent work in the philosophy of biology has attempted to clarify and defend the use of the biodiversity concept in conservation science. I argue against these views, and give reasons to think that the biodiversity concept is a poor fit for the role we want it to play in conservation biology on both empirical and conceptual grounds. Against pluralists, who hold that biodiversity consists of distinct but correlated properties of natural systems, I argue that the supposed correlations between these properties (...) are not tight enough to warrant treating and measuring them as a bundle. I additionally argue that deflationary theories of biodiversity don’t go far enough, since a large proportion of what we value in the environment falls outside bounds of what could reasonably be called “diversity”. I suggest that in current scientific practice biodiversity is generally an unnecessary placeholder for biological value of all sorts, and that we are better off eliminating it from conservation biology, or at least drastically reducing its role. (shrink)

Philosophical discussions of species have focused on multicellular, sexual animals and have often neglected to consider unicellular organisms like bacteria. This article begins to fill this gap by considering what species concepts, if any, apply neatly to the bacterial world. First, I argue that the biological species concept cannot be applied to bacteria because of the variable rates of genetic transfer between populations, depending in part on which gene type is prioritized. Second, I present a critique of phylogenetic bacterial species, (...) arguing that phylogenetic bacterial classification requires a questionable metaphysical commitment to the existence of essential genes. I conclude by considering how microbiologists have dealt with these biological complexities by using more pragmatic and not exclusively evolutionary accounts of species. I argue that this pragmatism is not borne of laziness but rather of the substantial conceptual problems in classifying bacteria based on any evolutionary standard. (shrink)

The first comprehensive treatment of environmental philosophy, going beyond ethics to address the philosophical concepts that underlie environmental thinking and policy-making today Encompasses all of environmental philosophy, including conservation biology, restoration ecology, sustainability, environmental justice, and more Offers the first treatment of decision theory in an environmental philosophy text Explores the conceptions of nature and ethical presuppositions that underlie contemporary environmental debates, and, moving from theory to practice, shows how decision theory translates to public policy Addresses both hot-button issues, including (...) population and immigration reform, and such ongoing issues as historical legacies and nations' responsibility and obligation for environmental problems Anchors philosophical concepts to their practical applications, establishing the priority of the discipline's real-world importance. (shrink)

Environmental philosophy is a hybrid discipline drawing extensively from epistemology, ethics, and philosophy of science and analyzing disciplines such as conservation biology, restoration ecology, sustainability studies, and political ecology. The book being discussed both provides an overview of environmental philosophy and develops an anthropocentric framework for it. That framework treats natural values as deep cultural values. Tradeoffs between natural values are analyzed using decision theory to the extent possible, leaving many interesting question for philosophical deliberation. This framework is supposed to (...) be applicable in practical contexts. (shrink)

A quarter of a century ago, a group of scientists and conservationists introduced ‘biodiversity’ as a media buzzword with the explicit intent of galvanizing public and political support for environ...

Science is now studying biodiversity on a massive scale. These studies are occurring not just at the scale of larger plants and animals, but also at the scale of minute entities such as bacteria and viruses. This expansion has led to the development of a specific sub-field of “microbial diversity”. In this paper, I investigate how microbial diversity faces two of the classical issues encountered by the concept of “ biodiversity ”: the issues of defining the units of biodiversity and (...) of choosing a mathematical measure of diversity. I also show that the extension of the scope of biodiversity to microbial entities such as viruses and many other not-clearly-alive entities raises yet another foundational issue: that of defining a “lower-limit” of biodiversity. (shrink)

This chapter explores the idea that phylogenetic diversity plays a unique role in underpinning conservation endeavour. The conservation of biodiversity is suffering from a rapid, unguided proliferation of metrics. Confusion is caused by the wide variety of contexts in which we make use of the idea of biodiversity. Characterisations of biodiversity range from all-variety-at-all-levels down to variety with respect to single variables relevant to very specific conservation contexts. Accepting biodiversity as the sum of a large number of individual measures results (...) in an empirically intractable framework. However, large-scale decisions cannot be based on biodiversity variables inferred from local conservation imperatives because the variables relevant to the many systems being compared would be incommensurate with one another. We therefore need some general conception of biodiversity that would make tractable such large-scale environmental decision-marking. We categorise the large array of strategies for the measurement of biodiversity into four broad groups for consideration as general measures of biodiversity. We compare common moral justifications for the conservation of biodiversity and conclude that some form of instrumental value is the most plausible justification for biodiversity conservation. Although this is often interpreted as a reliance on option value, we opt for a broadly consequentialist characterisation of biodiversity conservation. We conclude that the best justified general measure of biodiversity will be some form of phylogenetic diversity. (shrink)

At least three different issues are commonly referred to by the term “the species problem”: one concerns the necessary properties of species, a second the processes responsible for the existence of species, and a third methods for inferring species limits. Solutions have recently been proposed to the first two problems, which are conceptual in nature (the third is methodological). The first equates species with metapopulation lineages and proposes that existence as a separately evolving metapopulation lineage be considered the only necessary (...) property of species. The second views the species category as a cluster concept and proposes that no single process or set of processes be considered necessary for the existence of species. Although these two solutions have been portrayed as being in conflict, they are, in fact, highly compatible. Moreover, the proposals in question clarify the problem concerning methods for inferring the limits of species, which has for a long time been confused with the problem concerning the necessary properties of species. Together these proposals provide the opportunity for biology to move beyond debates about the definition of the species category and focus on estimating the boundaries and numbers of species as well as studying the diverse processes involved in their origin and persistence. BioEssays 27:1263–1269, 2005. © 2005 Wiley Periodicals, Inc. (shrink)

This chapter contains sections titled: Historical and Current Views of Species Return to a Darwinian View of Species Practical Implications Postscript: Counterpoint References.

The project of this paper is to understand what a phylogenetic tree represents and to discuss some of the implications that this has for the practice of systematics. At least the first part of this task, if not both parts, might appear trivial—or perhaps better suited for a single page in a textbook rather than a scholarly research paper. But this would be a mistake. While the task of interpreting phylogenetic trees is often treated in a trivial way, their interpretation (...) is tied to foundational conceptual questions at the heart of systematics—questions whose answers are hotly disputed. I have previously argued that widely shared ideas about the meaning and interpretation of phylogenetic trees are inconsistent with species concepts other than some genealogical version of a phylogenetic species concept (Velasco 2008). Here I rely on a similar approach and concentrate on the implications of the necessary conditions underlying the inferences that we make using phylogenetic trees. I argue that common practices for the interpretation and use of trees are in conflict and that unacceptable principles about species as units of phylogeny must be given up. According to the view that I will develop, all phylogenetic trees depict the history of populations. The branches on trees represent collections of population lineages through time and the splits represent population lineage splits. This is true regardless of whether the tips of the trees are themselves populations, or are species or higher taxa. Although this conclusion might be paired naturally with a view that species must be monophyletic groups, this population-centric view of trees is independent of that view of species. If we still want to have species that are paraphyletic groups of populations, this is permissible as long as we also do not treat species as the units of phylogeny. This population-centric view opposes a species-centric view of phylogeny and might be called a “rank-free” approach since it entails that we do not need to determine which groups are species (which is partly a ranking question) in order to build a tree. This conclusion and the argument for it are meant to be consistent with, but not require, acceptance of the conclusions of Velasco (2008) regarding species. (shrink)

The recent conception of biodiversity proposed by James Maclaurin and Sterelny was developed mostly with macrobiological life in mind. They suggest that we measure biodiversity by dividing life into natural units (typically species) and quantifying the differences among units using phenetic rather than phylogenetic measures of distance. They identify problems in implementing quantitative phylogenetic notions of difference for non-prokaryotic species. I suggest that if we focus on microbiological life forms that engage in frequent, promiscuous lateral gene transfer (LGT), and their (...) associated reticulated phylogenies, we need to rethink the notion of species as the natural unit, and we discover additional problems with phylogenetic notions of distance. These problems suggest that a phenetic approach based on morphospaces has just as much appeal, if not more, for microbes as they do for multi-cellular life. Facts about LGT, however, offer no new insight into the additional challenge of reconciling units and differences into a single measure of biodiversity. (shrink)