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6. To Be or Not To Be: Where Is Self-Preservation in Evolutionary Theory?
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6To Be or Not To Be: Where Is Self-Preservation in Evolutionary Theory? Pamela Lyon Cooperation, it is commonly said, is a puzzle for evolutionary biology because of the intrinsic selfishness of living things (Queller 1997; Sachs et al. 2004). So foundational is selfishness to the contemporary theory of natural selection that the most influential account of the evolution of cooperation and altruism, kin selection, is based on it (Lehmann et al. 2007; Sober and Wilson 1998). Organisms are willing to moderate or even sacrifice their own existential imperatives to be, to grow, and to reproduce for kin, first and foremost, because kin are the closest to self, genetically speaking. In this chapter, I argue that the evolution of selfishness is itself a puzzle, one rarely apprehended much less addressed. I am not concerned here with the psychological implications of the term selfishness, the units of selection debate, or any other battleground of the sociobiology conflict. Rather, I am concerned with the simple idea that at some point, in the history of life on earth, a selfordering , autocatalytic chemical system developed characteristics to which selfishness could be attributed. The various hypotheses of the origin of life and the major transitions of evolution currently on offer, henceforward referred to as origins and transitions narratives—whether replicator-first (Maynard Smith and Szathmáry 1995), metabolism-first (Wächtershäuser 1988), RNA world (Gilbert 1986), lipid world (Segré et al. 2001), peptide world (Nelson et al. 2000), virus world (Koonin et al. 2006), communal, gene-swapping progenotes (Woese 1998), biological big bang (Koonin 2007), or panspermia (Hoyle and Wickramasinghe 2000)—all share the assumption, usually tacit, that somehow selfishness entered the world. Put another way, they assume the emergence of the sort of self-preserving, self-organized complexity that provides a minimal basis for attributing selfishness to a system. So potent was the emergence of this trait that evolutionary theorists still ponder and debate about how it was overcome, because overcome it must have been (so it is said) to produce the routine wonders of evolution that abound today. Selfishness cannot simply be assumed, however. That a chemical system developed the impetus not merely to replicate, like a crystal, but to replicate specific sequences of complex molecules and persist against existential threat, are phenomena that demand explanation . None of the inorganic self-ordering, autocatalytic, dissipative structures known to 106 Pamela Lyon contemporary science does this (Abel and Trevors 2006; Kauffman 2000; Orgel 1992). A crystal, a candle flame, a hurricane, or a Bénard cell does not seek resources when the material conditions for continued catalysis runs out; they cease. Living things do so until all options are exhausted. Some of the simplest organisms engage in surprisingly elaborate behaviors to forestall cessation. In On the Origin of Species, Charles Darwin observed that it is “so easy . . . to think that we give an explanation when we only restate a fact” (1996, 389). Darwin’s admonition was aimed at those who uncritically invoked “such expressions as the ‘plan of creation,’ [and] ‘unity of design,’” to explain the abundant diversity of life and the neat adaptive fit between an organism and its environs. I claim that Darwin’s admonition applies to many current theoretical deployments of selfishness in evolutionary biology. So routinely and uncritically is selfishness invoked that it does seem to pass for explanation. This is a mistake, I believe, for two reasons. First, assuming selfishness as a universal brute trait of prebiotic and biological entities obscures a major transition in the history of life on earth. This is the transition from a selfreplicating , autocatalytic chemical system to what Godfrey-Smith (2009; this volume) calls a “Darwinian individual.” Following Lewontin, Godfrey-Smith sets out three characteristics of a Darwinian individual: it is a member of a population of entities that (a) differ from one another in some character relating to morphology, physiology, or behavior (variation ), in ways that (b) make a difference to the individual’s survival and/or reproductive success (fitness) and (c) can be passed to offspring (heritability). A Darwinian individual, so defined, need not be actively self-preserving and/or selfextending . In biological evolution, however, the characteristics of active self-preservation and self-extension via growth and reproduction are simply facts about whatever biological entity is under consideration. Viruses and prions are exceptions to the growth condition, but the rapid evolvability of the viral protein coat provides evidence of self-preservation. Thus, the characteristics of self-preservation and self-extension are typically...