S. K. Sarkar

Since the late 1990s, the characterization of complete DNA sequences for a large and taxonomically diverse set of species has continued to gain in speed and accuracy. Sequence analyses have indicated a strikingly baroque structure for most eukaryotic genomes, with multiple repeats of DNA sequences and with very little of the DNA specifying proteins. Much of the DNA in these genomes has no known function. These results have generated strong interest in the factors that govern the evolution of genome architecture. While adaptationist ‘just so’ stories have been offered, recent theoretical analyses based on mathematical population genetics strongly suggest that non-adaptive processes dominate genome architecture evolution. This article critically synthesizes and develops these arguments, explicating a core argument along with several variants. It provides a critical assessment of the evidence that supports these arguments’ premises. It also analyses adaptationist responses to these arguments and notes potential problems with the core argument. These theoretical analyses continue the molecular reinterpretation of evolution initiated by the neutral theory in 1968. The article ends by noting that some of these arguments can also be extended to evolution at higher levels of organization which raises questions about adaptationism in general. This remains a puzzle because there is probably little reason to doubt that many organismic features are genuine adaptations. 1 Introduction2 Preliminaries: Senses of Adaptationism3 Genome Architecture3.1 Surprises of early eukaryotic genetics3.2 Genome structure, post-20014 The Case against Adaptationism4.1 Just so stories versus population genetics4.2 The core argument4.3 Three variants of the core argument4.4 Examples: Non-adaptive features of the genome5 Adaptationist Responses6 Concluding Remarks

This paper analyzes the interaction between science, philosophy and politics (including ideology) in the early work of J. B. S. Haldane (from 1922 to 1937). This period is particularly important, not only because it is the period of Haldane's most significant biological work (both in biochemistry and genetics), but also because it is during this period that his philosophical and political views underwent their most significant transformation. His philosophical stance first changed from a radical organicism to a position far more compatible with mechanical materialism. The primary intellectual influence that was responsible for this shift was that of F. G. Hopkins. Later, Haldane came to accept Marxism and its official metaphysics, dialectical materialism, a move that let him accept the materialist conception of the world while still maintaining a resolute distance from mechanism. Throughout all these changes, what is most obvious is the influence of science on Haldane's philosophical views. An influence in the opposite direction is far less apparent.

This response to Sober's (2008) Evidence and Evolution draws out and criticizes some consequences of his analysis because of its reliance on a likelihood framework for adjucating the dispute between (Intelligent Design) creationism and evolution. In particular, Sober's analysis does not allow it to be formally claimed that evolutionary theory better explains living phenomena than Intelligent Design and makes irrelevant the contribution of the theory of evolution by natural selection to assessments of the status of the argument from design. Finally, a rudimentary alternative framework for theory confirmation is presented here which avoids these conclusions by rejecting likelihoodism and deploying multiple criteria to the problem of scientific theory choice

It is shown that complex adaptations are best modelled as discrete processes represented on directed weighted graphs. Such a representation captures the idea that problems of adaptation in evolutionary biology are problems in a discrete space, something that the conventional representations using continuous adaptive landscapes does not. Further, this representation allows the utilization of well-known algorithms for the computation of several biologically interesting results such as the accessibility of one allele from another by a specified number of point mutations, the accessibility of alleles at a local maximum of fitness, the accessibility of the allele with the globally maximum fitness, etc. A reduction of a model due to Kauffman and Levin to such a representation is explicitly carried out and it is shown how this reduction clarifies the biological questions that are of interest.

This paper attempts a critical reappraisal of Nagel's (1961, 1970) model of reduction taking into account both traditional criticisms and recent defenses. This model treats reduction as a type of explanation in which a reduced theory is explained by a reducing theory after their relevant representational items have been suitably connected. In accordance with the deductive-nomological model, the explanation is supposed to consist of a logical deduction. Nagel was a pluralist about both the logical form of the connections between the reduced and reducing theories (which could be conditionals or biconditionals) and their epistemological status (as analytic connections, conventions, or synthetic claims). This paper defends Nagel's pluralism on both counts and, in the process, argues that the multiple realizability objection to reductionism is misplaced. It also argues that the Nagel model correctly characterizes reduction as a type of explanation. However, it notes that logical deduction must be replaced by a broader class of inferential techniques that allow for different types of approximation. Whereas Nagel (1970), in contrast to his earlier position (1961), recognized the relevance of approximation, he did not realize its full import for the model. Throughout the paper two case studies are used to illustrate the arguments: the putative reduction of classical thermodynamics to the kinetic theory of matter and that of classical genetics to molecular biology.

Maynard Smith’s defenses of adaptationism and of the value of optimization theory in evolutionary biology are both criticized. His defense does not adequately respond to the criticism of adaptationism by Gould and Lewontin. It is also argued here that natural selection cannot be interpreted as an optimization process if the objective function to be optimized is either (i) interpretable as a fitness, or (ii) correlated with the mean population fitness. This result holds even if fitnesses are frequency-independent; the problem is further exacerbated in the frequency-dependent context modeled by evolutionary game theory. However, Eshel and Feldman’s new results on “long-term” evolution may provide some hope for the continuing relevance of the game-theoretic framework. These arguments also demonstrate the irrelevance of attempts by Intelligent Design creationists to use computational limits on optimization algorithms as evidence against evolutionary theory. It is pointed out that adaptation, natural selection, and optimization are not equivalent processes in the context of biological evolution.

  A classification of models of reduction into three categories — theory reductionism, explanatory reductionism, and constitutive reductionism — is presented. It is shown that this classification helps clarify the relations between various explications of reduction that have been offered in the past, especially if a distinction is maintained between the various epistemological and ontological issues that arise. A relatively new model of explanatory reduction, one that emphasizes that reduction is the explanation of a whole in terms of its parts is also presented in detail. Finally, the classification is used to clarify the debate over reductionism in molecular biology. It is argued there that while no model from the category of theory reduction might be applicable in that case, models of explanatory reduction might yet capture the structure of the relevant explanations

Joshua Lederberg was one of the pioneers of molecular genetics perhaps best known for his discovery of genetic recombination in bacteria which earned him a Nobel Prize in 1958. Lederberg’s interests were broad including the origin of life, exobiology and emerging diseases and artificial intelligence in his later years. This article contains the transcription of an interview in excerpts, documenting the interactions between Lederberg and fellow biologist J.B.S. Haldane which lasted from 1946 until Haldane’s death in Kolkata in 1964.

Maynard Smith notes that he provides a natural history and not a philosophical analysis of the use of concepts of information in contemporary biology. Just a natural history, however rich, would do little to resolve the ongoing controversy about the role of these concepts in biology. None of the disputants deny that the biological use of these concepts is pervasive. The dispute is about whether these concepts—and the framework in which they are embedded—continue to be of explanatory value in contemporary biology. Fortunately, Maynard Smith does much more than provide a natural history: his contribution is also a sustained attempt to justify many of the uses of information in biology.

Two questions are raised for Grafen’s formal darwinism project of aligning evolutionary dynamics under natural selection with the optimization of phenotypes for individuals of a population. The first question concerns mean fitness maximization during frequency-dependent selection; in such selection regimes, not only is mean fitness typically not maximized but it is implausible that any parameter closely related to fitness is being maximized. The second question concerns whether natural selection on inclusive fitness differences can be regarded as individual selection or whether it leads to a departure from the central motivation that led to the formal darwinism project, viz., to show that “Darwinian” evolution through individual selection leads to “good design” or phenotypic adaptation through trait optimization

This paper analyzes the development of evolutionary theory in the period from 1918 to 1932. It argues that: (i) Fisher's work in 1918 constituted a not fully satisfactory reduction of biometry to Mendelism; (ii) there was a synthesis in the 1920s but that this synthesis was mainly one of classical genetics with population genetics, with Haldane's The Causes of Evolution being its founding document; (iii) the most important achievement of the models of theoretical population genetics was to show that natural selection sufficed as a mechanism for evolution; and (iv) Haldane formulated a prospective evolutionary theory in the 1920s whereas Fisher and Wright formulated retrospective theories of evolutionary history.

The following piece is a response to the critiques from Frank, Garson, and Odenbaugh. The issues at stake are: the definition of biodiversity and its normativity, historical fidelity in ecological restoration, naturalism in environmental ethics, and the role of decision theory. The normativity of the concept of biodiversity in conservation biology is defended. Historical fidelity is criticized as an operative goal for ecological restoration. It is pointed out that the analysis requires only minimal assumptions about ethics. Decision theory is presented as a tool, not a domain-limiting necessary requirement for environmental philosophy

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

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