A Philosophical Examination of the Processes of Evolution
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RADAR Research Archive and Digital Asset Repository Natural Selection and Natural Processes: a philosophical examination of the processes of evolution Colin Beckley (2012) https://radar.brookes.ac.uk/radar/items/76e8697b-c2b8-4d91-8790-08b637fcbc79/1/ Note if anything has been removed from thesis: Copyright © and Moral Rights for this thesis are retained by the author and/or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder(s). The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders. When referring to this work, the full bibliographic details must be given as follows: Beckley, C, (2012), Natural Selection and Natural Processes: a philosophical examination of the processes of evolution, PhD, Oxford Brookes University WWW.BROOKES.AC.UK/GO/RADAR Natural Selection and Natural Processes: A Philosophical Examination of the Processes of Evolution Colin Beckley June 2012 This thesis is submitted in partial fulfilment of the requirements of the award of Doctor of Philosophy awarded by Oxford Brookes University 1 Acknowledgements From the earliest stages, I have been grateful to Stephen Boulter and Mark Cain from the Philosophy department at Oxford Brookes University, who invited me to take on the PhD under their supervision. In particular, Stephen’s deep questioning of some of the fundamentals proved invaluable as the thesis progressed. I am also very grateful to Andrew Lack from the Biology department at Brookes, who took on the role of biology supervisor. Without Andrew’s insights, support and encouragement, this thesis may never have been completed. Also from the biology department, I thank Casper Breuker for the provision of many pertinent papers concerning evolutionary theory. Thanks also to Simon Baker for giving his time and illustrating the strange and curious world of the prokaryotes. I wish also to thank the following staff at Brookes for their help and cooperation: Beverley Clack, David Evans, Martin Groves, Catherine Joyejob, Marlene Morrison, Jill Organ and Stephen Rayner. External to Brookes, I thank Noam Chomsky, who kindly went through my initial proposals and prevented me from committing a philosophical faux pas. I am particularly grateful to Trevor Hussey who over many years has shown such friendship whilst maintaining a very healthy constructive criticism. This has proved priceless. To Antonio Lima-de-Faria I also give special thanks for providing many scientific papers and references that enabled me to a wider and necessary appreciation of the issues. I also thank Antonio and his wife Helene for the kind reception at their home in Lund and the discussion and clarification of Antonio’s ideas. Thanks also to Philip Ball and Robert M Hazen for sending and sharing important scientific papers. I am also grateful to Mike Arnautov, who kindly took time to read through and comment wisely on the parts of my thesis that I was preparing for a series of lectures for the Wycombe Philosophy Association. I am very grateful to both Judith Payne and Elaine Rogers for taking on the onerous task as proof readers and calmly revealing my many oversights and omissions. Finally, I wish to thank Maryam, whose love and support have been so valuable to me. 2 Contents Page Abstract 4 Introduction 5 Natural Selection Chapter 1: The Historical Exposition 13 Chapter 2: Problems with the Concept of Fitness 21 Chapter 3: The Ontological Question 31 Chapter 4: A Critical Analysis 37 Chapter 5: The Further Extended Principle of Natural Selection 50 Demarcation Chapter 6: Seeking Boundaries 55 Chapter 7: Genetic Exchange 61 Form, Function and Order Chapter 8: The Constraints: Symmetry, Asymmetry and Patterns in Nature 72 Chapter 9: D’Arcy Thompson and Lima-de-Faria 88 Chapter 10: Constraints or Determinants: Gravity, Temperature, Nutrition and Size 101 Explanation and Evolutionary Pluralism Chapter 11: Explanation in Evolutionary Biology 118 Chapter 12: Explanation, Teleology and Anthropomorphic Language 135 Chapter 13: Evolutionary Pluralism 142 Chapter 14: Conclusions 154 Appendix 1 165 Appendix 2 167 Appendix 3 169 Appendix 4 171 Appendix 5 175 References 176 3 Abstract This thesis concerns evolution and how it is explained. The ambition here is to identify clearly the many aspects of evolution, and to evaluate past and present explanations of evolution for their coherence and validity. Historically natural selection has been taken to be the central and main explanans, with other explanations playing lesser roles. Here it will be argued that the sheer complexity and diversity within nature cannot be accounted for by any single explanatory mechanism and that a plurality of explanatory mechanisms is required. Loading natural selection with the main weight of explanation is an overburden which, far from strengthening its explanatory powers, actually renders it vacuous. A critical historical and philosophical examination of the concept of natural selection reveals that it has never received a formal scientific definition that commands universal respect. This has created a problem of demarcation between that which natural selection can legitimately be said to explain and that which it cannot. In fact, the ontology of natural selection is equivocal, giving rise to the many controversies that have plagued evolutionary biology. The disambiguation of the concept of natural selection is the principle aim of this thesis and guidelines on how this should be accomplished are provided. However, should these reforming guidelines fail to achieve a consensus then a more radical alternative is proposed. It is recommended that the selective terminology is replaced with the less anomalous and demanding principle of ‘meeting the conditions of existence’. Moreover, talk of the evolution and origins by means of natural selection is to be replaced by talk of evolution and origins by means of natural processes. Finally, drawing from a ‘Structuralist’ alternative, it will be demonstrated that biological evolution should not be divorced from general or cosmological evolution. Rather, elucidation should be drawn more deeply from the fields of physics, chemistry, mathematics and topology, without the use of selection-tinted spectacles. 4 Introduction Within evolutionary biology and the accompanying theoretical and philosophical literature, there are several unresolved and contentious issues, none more so than those that arise from the use of the concept of natural selection. The main issue here is that the term covers too many different relationships and that little, if anything, is ruled out. Natural Selection was seen originally as an important distinction to theological explanation but it is identified here that we have outgrown the early concept. There are today so many uses ranging from early ‘Malthusian natural selection’, to ‘positive selection’, to ‘negative selection’ to ‘balancing selection’ and, far from least but most anomalously, to ‘lifted or relaxed selection’. With such wide contrariness one must question the heuristic value of the concept and whether the application of natural selection or ‘selection’ is little more than a linguistic tick. Boundaries and parameters do matter and not exclusively for scientific purposes. During the 1920s, 1930s and 1940s natural selection was inappropriately applied to justify some obnoxious eugenic and socially racialist politics. It is justifiable and easy to condemn these applications as they transcended the intended usage. Unfortunately it is far less easy to provide clear barriers to indicate the proper application of natural selection. I will argue here, in the context of science, that if the concept of natural selection cannot be clearly defined with appropriate parameters then it is advisable to talk directly and more specifically of natural processes. The purpose of this thesis is to demonstrate that these issues can be resolved by some fairly simple changes to both the terminology currently employed and the expectations of the theorist. These changes will enable evolutionary theory to be perceived with more clarity, avoiding many of the philosophical pitfalls. To achieve this, the issues will be identified and examined critically but with a view to resolution that does not compromise evolutionary theory. Arguably, natural selection has been perceived as the classical explanation of evolutionary change, with other explanations playing lesser roles. However, this is not without problem. My original ambition was to provide natural selection with a definition that was clear and precise, thus avoiding many of the controversies, paradoxes and problems that have afflicted evolutionary theory. This has proved elusive. The main problem is that if one tightens the definition of natural selection then one loses a great deal of explanatory power. On the other hand, if one generalises the definition then one has the spectre of tautology, untestability and vacuity, with natural selection looking synonymous with evolution. And yet, all is not lost. There is a solution to the dilemma: there are many underlying naturalistic processes that can explain why evolution occurs. These will be explored and argued for. Furthermore, it will be demonstrated that this approach is easy to articulate and follow in principle, avoiding many of the