Historically, one of the most controversial aspects of Darwinian evolution has been the prominent role that randomness and random change play in it. Most biologists agree that mutations in DNA have random effects on fitness. However, fitness is a highly simplified scalar representation of an enormously complex phenotype. Challenges to Darwinian thinking have focused on such complex phenotypes. Whether mutations affect such complex phenotypes randomly is ill understood. Here I discuss three very different classes of well-studied molecular phenotypes in which (...) mutations cause nonrandom changes, based on our current knowledge. What is more, this nonrandomness facilitates evolutionary adaptation. Thus, living beings may translate DNA change into nonrandom phenotypic change that facilitates Darwinian evolution. (shrink)

In this paper, I wish to challenge theory-biased approaches to scientific knowledge, by arguing for a study of theorizing, as a cognitive activity, rather than of theories, as abstract structures independent from the agents’ understanding of them. Such a study implies taking into account scientists’ reasoning processes, and their representational practices. Here, I analyze the representational practices of geneticists in the 1910s, as a means of shedding light on the content of classical genetics. Most philosophical accounts of classical genetics fail (...) to distinguish between the purely genetic, or Mendelian level, and the cytological one. I distinguish between them by characterizing them in terms of their respective associated representational practices. I then present how the two levels were articulated within Morgan’s theory of crossing-over, and I describe the representational technique of linkage mapping, which embodies the “merging” of the Mendelian and cytological levels. I propose an analysis of the mapping scheme, as a means of enlightening the conceptual articulation of Mendelian and cytological hypotheses within classical genetics. Finally, I present the respective views of three opponents to Morgan in the 1910s, who had a different understanding of the articulation of cytology and Mendelism, and entertained different views concerning the role and proper interpretation of maps. I propose to consider these diverging perspectives as instantiating what I call different “versions” of classical genetics. (shrink)

Philosophical theories about reduction and integration in science are at variance with what is happenign in science. A realistic approach to science show that possibilities for reduction and integration are limited. The classical ideal of a unified science has since long been rejected in philosophy. But the current emphasis on interdisciplinary integration in philosophy and in science shows that it survives in a different guise. It is necessary to redress the balance, specifically in biology. Methodological analysis shows that many of (...) the grand interdisciplinary theories involving biology actually represent pseudo-integration covered up by inappropriate, overgeneral concepts. Integrationism is not bad, but it must be kept within reasonable bounds. If the present analysis is appropriate, there will have to be fundamental changes in research strategy both in science and in the philosophy of science. (shrink)

Interdisciplinary integration has fundamental limitations. This is not sufficiently realized in science and in philosophy. Concerning scientific theories there are many examples of pseudo-integration which should be unmasked by elementary philosophical analysis. For example, allegedly over-arching theories of stress which are meant to unite biology and psychology, upon analysis, turn out to represent terminological rather than substantive unity. They should be replaced by more specific, local theories. Theories of animal orientation, likewise, have been formulated in unduly general terms. A natural (...) history approach is more suitable for the study of animal orientation. The tendency to formulate overgeneral theories is also present in evolutionary biology. Philosophy of biology can only deal with these matters if it takes a normative turn. Undue emphasis on interdisciplinary integration is a modern variant of the old unity of science ideal. The replacement of the ideal by a better one is an important challenge for the philosophy of science. (shrink)

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. (shrink)

This thesis aims to propose and defend a new way of analysing and understanding the origin of genetics (from Mendel to Bateson). Traditionally philosophers used to analyse the history of genetics in terms of theories. However, I will argue that this theory-based approach is highly problematic. In Chapter 1, I shall critically review the theory-driven approach to analysisng the history of genetics and diagnose its problems. In Chapter 2, inspired by Kuhn’s concept “exemplar”, I shall make a new interpretation of (...) exemplar and introduce an exemplar-based approach. Before introducing my exemplar-based analysis, I find it necessary to scrutinise the origin of genetics from Mendel to Bateson. In Chapter 3, I shall reinterpret Mendel’s work on Pisum by re-examining Mendel’s paper (1865) and its historical research context. In Chapter 4, by carefully examining the conceptual changes, I argue that the rediscovery event in 1900 should be better characterised as attempts of incorporating Mendel’s work with the work of “rediscoverers” (i.e. de Vries, Correns, Tschermak, and Bateson) rather than a mere reintroduction to Mendel’s work. In Chapter 5, I shall use the exemplar-based approach to analysing and interpreting the origin of genetics from Mendel to Bateson. In Chapter 6, I shall defend my exemplar-based characterisation of the origin of genetics by dismissing the potential responses from the theory-driven one, critically examining a potential mechanism-based analysis, and making the further notes on the implication of taking the exemplar-based approach to investigate scientific practice. (shrink)