Evolution in Domestic Politics and the Development of Rivalry: The Bolivia-Paraguay Case

This chapter describes an evolutionary approach to interstate conflict and rivalry, adapting evolutionary concepts from the natural sciences. The evolutionary model of rivalry focuses on evolution in the political leadership within nation-states, focusing on evolutionary challenges from a changing international and domestic political environment. The model identifies factors that contribute to the evolution of leaders and policies within adversary states, and suggests consequences of this evolution for relations between the states. The model is examined through a brief case study of the BoliviaParaguay rivalry and a review of recent quantitative evidence on rivalry, which together suggest a great deal of support. The chapter concludes by discussing the implications of this approach for future research on rivalry and on world politics more generally. An earlier version of this chapter was presented at the Conference on Evolutionary Perspectives on International Relations, Bloomington, Indiana, December 1998. The author wishes to thank the other conference participants for their valuable comments and suggestions. Evolution in Domestic Politics and the Development of Rivalry: The Bolivia-Paraguay Case Evolutionary approaches have long been important in the study of biological and anthropological phenomena, but evolution and related concepts have generally been ignored in the social sciences. Possible explanations for this lack of attention include the controversial status of evolution in popular society, the rejection of biological or genetic factors as sources of human behavior, and the belief that the biological sciences are not an appropriate source of ideas for social scientific research. Social scientists are finally beginning to proclaim the merits of evolutionary approaches in studying social phenomena, though, as suggested by a 1996 special issue of International Studies Quarterly. This chapter uses evolutionary concepts to develop a model of militarized interstate rivalry, focusing on evolution with the domestic political systems of two adversary nation-states. Militarized interstate rivalry refers to a longstanding, competitive relationship between two adversaries who engage in numerous militarized confrontations (Goertz and Diehl 1993; Hensel 1996). Although there have been relatively few rivalries in the modern era, enduring rival adversaries account for one-fourth of all interstate wars and territorial changes since 1816, roughly forty percent of all militarized interstate disputes and violent territorial changes, and approximately half of all international crises (Goertz and Diehl 1992; Hensel 1998a). Relations between rivals have been argued to be more conflictual than relations between other types of states, largely because of the distrust and hostility that are said to characterize rivalry. Despite the apparent importance of the rivalry concept, though, little systematic research has addressed the origins of rivalries, with most research focusing on the dynamics of established rivalries or on the termination of rivalry (including the Thompson and Rasler contributions to this volume). Perhaps the most prominent explanation of interstate rivalry suggests that most rivalries can be explained by preexisting structural or environmental factors or by "shocks" in the external environment (e.g., Goertz and Diehl 1995). Despite the emphasis on preexisting factors in the current rivalry literature, the central elements of a traditional biological approach to evolution offer important insights into the development of conflictual relationships between nation-states. In particular, the notions of fitness, adaptation, and selection offer useful insights into the identity of state leaders and the foreign policies that they implement. After describing the basic elements of an evolutionary approach, this chapter uses these elements to develop a model to account for the evolution of conflictual relationships between nationstates. It then examines the utility of this model with a brief case study of the rivalry between Bolivia and Paraguay, and with an examination of recent quantitative evidence on the origins and dynamics of 1 rivalry. This chapter concludes by discussing the implications of the evolutionary approach for future research in international relations. Evolutionary Approaches The concept of evolution has been used most widely in the natural sciences. Evolutionary approaches are commonly used to study such phenomena as adaptive change within established species (sometimes termed vertical evolution), the increasing diversity of populations and development of new species (horizontal evolution), and the development of societal behaviors or means of organization (social or cultural evolution). The next section of this chapter identifies the central themes of such evolutionary approaches from the natural sciences, with the goal of developing an evolutionary approach that is relevant to the social sciences in general and the study of interstate rivalry more specifically. One important characteristic of evolutionary approaches is the rejection of determinism as an explanation for observed phenomena, in favor of evolutionary processes reflecting unfolding, cumulative processes of change over time. Systems or populations in evolutionary theory are seen as changing over time in response to environmental challenges, reaching their particular state or condition at any given point in time through a series of changes. The study of evolution, then, involves replacing such static questions as "what is it" or "how does it work? " (whether this refers to a species' bodily structure, a domestic political system, or a competitive international relationship) with more dynamic, process-oriented questions like "how did it come to work that way and not some other way? " A second characteristic of most evolutionary approaches -despite the emphasis on cumulative processes of change -is the absence of teleological ends, or the rejection of progressor perfectiondirected change. Thus, while a given evolutionary adaptation may improve an organism's fitness and improve its ability to survive in its current environment, there is no guarantee that the adaptation represents ultimate "progress," movement toward "perfection," or fulfillment of any grand cosmic design. Indeed, the same adaptation that improves fitness in one set of environmental conditions may actually reduce fitness in a subsequent set of conditions. Beyond these two central assumptions, explanations of evolutionary change typically revolve around the notions of the organism, the environment, variation, fitness, adaptation, and natural selection. The organism in evolutionary stories -the entity facing an evolutionary challenge -is generally a species, a specific individual, or a social grouping. The "environment" refers to the setting in which this organism lives and works, and typically includes such elements as food, shelter, climate, and predators. 1 Useful natural-science sources on evolution that were consulted include Darwin (1859/1968), Eldredge (1985), Keller and Lloyd (1992), Mayr (1988), and Minkoff (1983). 2 Changes in this environment produce the need for evolution, by making it difficult for the organism to survive in its current form. Typical evolutionary challenges from the environment include the introduction of a new predator, a shortage in the supply of food or shelter, or changes in the climate. When such environmental challenges arise, survival becomes a contest between different individuals or species. "Variation" refers to the traits or behaviors that distinguish between individuals or species; it is this variation that allows certain individuals or species to deal with evolutionary challenges better than others. "Fitness" generally refers to the ability to survive and reproduce in a particular environment or the probabilistic expected time to extinction for an organism or species given a particular time and environment (Beatty 1992); the relative fitness of organisms is influenced by their variation in relevant traits and behaviors. A serious environmental challenge to an organism or species may culminate in several different outcomes. The first, evolutionary "adaptation," refers to alterations in the traits or capacities of the organism that enable it to solve (or to improve on previous solutions for) problems posed by the environment, in such a way as to increase its relative fitness or likelihood of survival (Burian 1992; West-Eberhard 1992). Examples might include the development of a new physical attribute or a behavior modification, which would allow the organism to avoid or defend against predators or to obtain scarce food or shelter. An organism that fails to adapt to environmental challenges, though, may fall victim to "natural selection. " Originally articulated by Darwin in The Origin of Species, the selection process begins with competing organisms that differ from each other in one or more ways (i.e., there must be some type of variation in traits). Natural selection refers to a process by which organisms with better fitness are more likely to survive and reproduce successfully than other organisms, generally leading to the preservation of organisms with favorable variations and the rejection of organisms with less favorable variations -essentially, a process of the "survival of the fittest" (Darwin 1859/1968: 130-131; Endler 1992; Hodge 1992). An organism that does not adapt to deal with the changes in the environment, then, may be "selected out" in favor of competitors that are better able to deal with the environment. Although each of these evolutionary concepts was originally developed in the natural sciences, many of them also offer useful insights for the social sciences. The next section of this chapter develops an evolutionary approach to interstate rivalry, focusing on domestic politics in two potential rival nationstates. Despit