Niche construction and the role of environment : towards a new logic of natural selection explanations

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Biological systems may move in, feed on, socialize with, and change the world around it. How should we explain how these systems develop, act, think, and evolve? Internalists and externalists urge us to look past the entangled complexities and seek the drivers of life internally (such as genes or the brain, etc.) or externally (in the developmental, informational, social, etc. environment). Of course, everyone is an interactionist in a minimal sense, given that no system is entirely externally controlled or completely self sufficient, but sophisticated internalists and externalists think it fruitful to make intelligent bets about where to look first and how to prioritize the internal and external causes. The focus of this dissertation is externalism in evolutionary biology. Elsewhere in biology and psychology, mounting evidence that organisms maintain life activities through feedback loops with the environment have motivated theories to expand the notion of "organism" or incorporate environment as scaffolds. However, in light of all this change, the theory of natural selection has managed to stay stubbornly externalist. What I study and critique in this dissertation is the firmly held presupposition that natural selection is an environmentally driven phenomena, an assumption that drives research to almost always seek natural selection explanations of complex, plastic, and constructing systems in terms of some complex, fluctuating, challenge in the environment. It doesn't have to be. I lay down the steps that lead towards a new logic of natural selection, a form of evolution that is not necessarily driven by the environment. The first step is to figure out whether and how explanations by natural selection are externalist. Fitness, the core concept of natural selection explanations, is about how good a trait is in dealing with environmental pressures (Chapter 1). Natural selection is seen as an optimizing process that fits organisms to environment; its presence detected from correlations between organism and environment (Chapter 2). Applications of evolutionary theory outside of biology, for instance, in entrepreneurship and organization studies, export what they think are the core, defining features of natural selection, and to them, it explicitly includes an environment that is the locus of control (Chapter 3). The second step is to figure out what it takes to budge this strong externalist stance towards natural selection. Behavior, the ability of organisms to interact with their environments, is a common dividing factor in evolutionary internalist versus externalist debates. The internalist Lamarckian position postulates an "internal will" that drives organism evolution and development toward greater complexity, with the idiosyncratic use-and-disuse of the will resulting in diversity between species. The externalist Darwinian program, at its most extreme, holds that all features of the organism, including behavior, are merely passively selected for by the environment. Post-Darwin, the internalist position questions how powerful and important natural selection is for the evolution of complex traits. The anti-externalists move? To show that internal and interacting causes weaken the power of natural selection, as if natural selection explanations are always externalist. Behaviors stand at the intersection of organism and environment, and thus have been used to adjudicate internalist/externalist positions. I will thus focus on one type of behavior--niche construction: the ability of organisms to change their experienced environments--to question the staunching externalism of natural selection explanations. The last step is to move towards a different move against externalism by incorporating niche construction into natural selection, as a condition of natural selection instead of the latter's product or antagonizing force. I analyze what happens to the notion of fitness when organisms differ in fitness because of their abilities and the individual environments that are constructed, mingled, and responded to (Chapter 1). I examine theories of niche construction (Niche Construction Theory, pioneered by Kevin Laland, John Odling-Smee, and others, Dialectical Biology, by Richard Levins and Richard Lewontin, and Denis Walsh's Situated Adaptationism) to drive a distinction between niche construction as constitutive versus alternative to natural selection (Chapter 2). This last step sets the motivation and foundations for a new theory of natural selection and fitness.