Ecological-Evolutionary Theory

Principles and Applications

Gerhard Lenski

• Publisher: Routledge
• Year: 2015
• eBook ISBN: 9781317260875
• Topic: Social Sciences
• Subtopic: Sociology
• Index: Social Sciences

For forty years, in a variety of books and articles, Gerhard Lenski has become the most influential proponent of ecological and evolutionary explanations of human societies, their development and transformations, from the Stone Age to the present. In his newest book, Lenski offers a succinct but comprehensive statement of the full body of his theory followed by demonstration of how it can be used to generate new and valuable insights when applied to a set of highly diverse issues. These include debates concerning the origin of ancient Israel and its distinctive culture, the rise of the West in the modern era, the highly varied trajectories of development of Third World nations in recent decades, and the failure of Marxist efforts to transform society in the Soviet Union and elsewhere. In the concluding chapter, Lenski discusses a number of other issues and areas where ecological-evolutionary theory may be fruitfully applied in the future.

Part I
Principles

1
Evolutionary Theory: An Introduction

One of the more surprising developments in the social sciences in recent decades has been the revival of interest in evolutionary theory. After more than half a century of rejection—even ridicule—evolutionism has again become a viable option in both anthropology and sociology while in archaeology it has become the dominant theoretical paradigm.

This is hardly what anyone anticipated in the half-century following World War I. Evolutionism had been tried and found wanting—and, indeed, in the harsh and unsentimental world of science, theories that have been discarded almost never get a second chance. Evolutionism was seen as a matter of interest only to students of the history of social thought and a few surviving proponents, such as V. Gordon Childe, William F. Ogburn, and Leslie White. But even Childe and Ogburn came to express reservations toward the end of their careers. Crane Brinton summed up the prevailing view of the period when he wrote, "Who now reads Spencer?"

Yet, somehow, despite the odds, evolutionary theory is flourishing again, and not only in the social sciences. In biology, its position is stronger now than it has ever been (Mayr, 1978, 1982), and evolutionary theories have even been adopted in the physical sciences (Calvin, 1969; Dickerson, 1978; Holland, 1984; Laszlo, 1987; Novikov, 1983; Strom and Strom, 1979).

Owing to the unusual history and scope of evolutionary theories, several questions need to be addressed before we can proceed to the first major task of this volume—namely examination of the basic principles of the new evolutionary theory in the social sciences. Specifically we need to consider the relation of this theory to other evolutionary theories, past and present.

First, we must ask how this theory is related to evolutionary theories in the biological and physical sciences. Are they linked merely by a dubious metaphor, as Nisbet and others have alleged, or are there more substantial ties? Then, how is this new social science version of evolutionary theory related to the older evolutionary theories of the nineteenth and early twentieth centuries? Is it merely a revival of these older theories, as Nisbet, Peel, Utz, Bock, and others have charged, or are there important differences? And, finally, what has been responsible for the surprising revival of interest in evolutionism in the social sciences? Why has evolutionary theory proved an exception to the general rule that scientific theories are rarely resurrected once they have been abandoned?

The Family of Evolutionary Theories

As the presence of evolutionary theories in all the major branches of science indicates, the new theory of societal evolution, which is the primary concern of this volume, is part of a larger family of related theories. The relationship of these theories is based on two things: (1) They share a common objective, and (2) they provide substantive grounding for one another.

The basic objective of all evolutionary theories is to explain processes of change, and more especially cumulative, macrochronic, and macrostructural change. Cumulative change is a distinctive kind of change associated with systems composed of multiple, interrelated parts. Within these systems, some parts change while others remain unchanged. Thus, cumulative change is a process that combines elements of continuity with elements of change; many parts of the system are preserved for extended periods while new parts are added and other parts are either replaced or transformed. Cumulative change is also a process in which the characteristics of a system at any single point in time have a significant impact on the system and its characteristics at successive times. The classic definition of biological evolution as "descent with modification" illustrates this type of change, but the distinctive nature of cumulative change is best understood when it is compared with noncumulative patterns of change, such as cyclical change (e.g., the annual cycle of seasons) or stochastic change (e.g., successive rolls of a pair of dice).

As noted, evolutionary theories are also concerned primarily with macrochronic and macrostructural change, which is to say that they are efforts to explain the more basic long-term transformations that have been observed within a particular field of study Thus, evolutionary theories in astronomy, for example, seek to explain the major structural changes that stars and star systems have undergone since the beginning of the universe (Novikov, 1983). In chemistry, evolutionary theories are designed to explain the basic changes that have occurred in the chemical composition of the earth and its atmosphere since their formation, especially the emergence of organic molecules from inorganic materials and the emergence of simple one-celled organisms from organic molecules (Calvin, 1969). In the biological sciences, evolutionary theories are concerned with the processes of reproduction, variation, and selection and their consequences for the changing patterns of plant and animal life from the time when life first appeared on our planet (Mayr, 1978), And in the social sciences, evolutionary theories seek to explain the various transformations that have occurred in our own species' way of life from earliest Paleolithic times to the present. Where other theories are content to deal with structural and functional relationships and with limited sequences of change, evolutionary theories insist on the necessity of explaining the most basic developments that have occurred over the total span of the history of various phenomena, be they star systems, chemical systems, life systems, or the social and cultural systems that humans have created.

This is not to say that evolutionary theories and theorists are uninterested in shorter and more limited sequences of change. On the contrary these are often matters of great concern, as will become evident later in this volume, for they provide some of the best opportunities for testing evolutionary theories. However, when analyzing these more limited patterns of change, evolutionists seek to establish the larger evolutionary context within which such developments occur and to utilize this information as an important aspect of their analysis.

Two other concepts that are shared by all the members of the family of evolutionary theories are divergence and emergence. Divergence is the process by which phenomena become increasingly dissimilar over extended periods, as in the case of the Indo-European languages or of Darwin's finches. Biologists refer to this tendency as "adaptive radiation." The fantastic diversity of both the world of nature and the world that humans have created are ever-present reminders of the process of divergence, as well as a measure of its importance.

The concept of emergence is essentially a special case of the more general concept of divergence. Emergence is the process by which significantly new structures and new processes evolve out of older structures and older processes, as when the first amphibians evolved from marine animals. Although the boundary separating emergence from other forms of divergence is fuzzy and difficult to specify, it is clear that some forms of divergence have had vastly more important consequences than others. Thus, the evolution of the first amphibians was far more significant for the subsequent development of life on this planet than was the evolution of the umpteenth species of Darwin's finches.

Of all the instances of emergence, the most important are those that underlie the distinctions we make between physical, chemical, biological, and sociocultural evolution. In each instance, an important threshold was crossed and an entirely new mode of evolution was set in motion. Thus, stellar evolution laid the foundation for chemical evolution, which, in turn, laid the foundation for biological evolution, which, eventually, led to the evolution of human societies. In other words, one of the basic principles of modern evolutionary theory is that the evolutionary process itself evolves (Boulding, 1970; Lenski and Lenski, 1974).

It follows that the various evolutionary theories are not only linked by similar objectives, principles, and concepts, but more importantly they are linked substantively in a causal process in which each new mode of evolutionary change has laid a foundation for the next mode of such change. For students of human social and cultural evolution, this means that they cannot ignore the biological foundations on which societal evolution rests; in short, theories of societal evolution must be grounded in, and compatible with, theories of biological evolution. This does not mean, however, that a reductionist approach to this relationship is justified, as sociobiologists have sometimes assumed. The concept of emergence is an important reminder of the fundamental error involved in such an approach.

A final feature shared by all of the newer theories of evolution is a commitment to probabilism (Lenski, 1970; Mayr, 1978). In this connection, bear in mind that deterministic models of change and development are universally rejected. As a result, the study of evolution, whether in astronomy, chemistry, biology, or the social sciences, is destined to remain an inexact science, since exact sciences require that processes have deterministic outcomes (Boulding, 1970). Sometimes, of course, the probabilities associated with specific evolutionary processes are so high that the distinction between probabilism and determinism has little meaning, but these are exceptions to the more general pattern.

In addition to the elements that all evolutionary theories share, there are others that are shared by some of them. The best example of this is the concept of transmittable systems of coded information, which are records of prior experience (i.e., DNA and symbol-based cultural information). These systems are essential components of evolutionary theories in the biological and social sciences, but they are absent in the physical sciences. Because of this important distinction, and because societal evolution is a direct outgrowth of biological evolution but only an indirect outgrowth of chemical and physical evolution, theories of societal evolution resemble theories of biological evolution much more closely than they do theories of chemical or stellar evolution. Thus, while social scientists may safely ignore the latter, they cannot ignore many aspects of the theory of biological evolution.

Older and Newer Evolutionary Theories Compared

The newer evolutionism of recent decades owes an enormous debt to scholars of the eighteenth and nineteenth centuries who pioneered in the formulation of evolutionary theory—scholars such as Turgot, Ferguson, Millar, Robertson, Spencer, Tylor, Morgan, Lamarck, and Darwin. These, and others like them, laid a foundation on which modern theories of evolution build. Above all, they established the cumulative nature of change and identified the basic processes of divergence and emergence. They also discovered many of the more specific mechanisms governing evolutionary processes.

Yet, having acknowledged our debt to these scholars, we need to recognize that the newer evolutionism differs from the older in significant ways. In the biological sciences, for example, the rise of the new science of genetics has had profound consequences for evolutionary theory One reason evolutionism went into eclipse in Darwin's later years and for many years thereafter was because he and other evolutionists of his day had no adequate explanation for the process of variation. Darwin's theory of natural selection could explain the elimination of various forms of life, but how and why did new forms arise? The new science of genetics, with its discovery of the processes of mutation, recombination, and genetic drift, provided answers to these questions.

While there has been no development in the social sciences with as profound an impact as this, more recent evolutionism in sociology, anthropology, and archaeology differ in several fundamental respects from their nineteenth- and early-twentieth-century predecessors. Above all, the older evolutionism generally lacked a satisfactory explanation of the causes of societal development and growth. As Marvin Harris (1968) has noted, early evolutionary theory in the social sciences tended to be either eclectic or racialist in its explanations. Modern evolutionary theory, in contrast, explains the most basic patterns and trends in human societies and their cultures in terms of some combination of the following: (1) humanity's common genetic heritage, (2) the various technologies our species has fashioned to enhance this heritage, (3) the resources and constraints of the biophysical environment, (4) the resources and constraints of the sociocultural environment, and (5) the impact of the process of intersocietal selection. This newer emphasis is the result of a number of significant developments in the social sciences, most notably the striking advances in archaeology, the growing appreciation of the explanatory power of ecological perspectives, and, not least of all, the experience of societies themselves in the last hundred years.

A second important difference between the older and newer evolutionary theories in the social sciences involves the concept of progress. In the older evolutionism there was a pervasive tendency to see progress in almost every sphere of life, from the technological to the moral. Contemporary evolutionists do not share this view. Over many extended periods, societal evolution seems to have resulted in a deterioration in the quality of life for the great majority of people, and lowered standards of morality as well. These trends are especially evident in the period from the end of the hunting and gathering era (ca. 7,000 B.C.) to the modern era (Lenski, 1970: 468-477). Furthermore, some contemporary evolutionists regard a catastrophic end to human history (e.g., via a nuclear holocaust) as a distinct possibility. Thus, when the term "progress" is used by evolutionists today, it refers to certain specific developments with a clear directional component (e.g., an increase in the division of labor) rather than to an improvement in the quality of life, as most nineteenth-century evolutionists would have meant the term. The closest today's evolutionists come to the older view is when some of us assert that the basic trend in sociocultural evolution has been a progressive expansion of the store of information available to the human societies viewed as a whole. This assertion, however, contains no assumptions about moral progress or any other form of human betterment.

Third, the newer evolutionary theory rejects the determinism that was often present in the older evolutionary theory. This change is largely a result of the tremendous impact that statistical theory has had on the social sciences since World War II. Even in situations where reliable quantitative data are lacking, contemporary evolutionists formulate their theoretical models in probabilistic terms.

Finally, compared with the work of Spencer, Tylor, Morgan, Sumner, and other nineteenth-century evolutionists, the newer evolutionism rests on a firmer and richer foundation of archaeological, ethnographic, and historical data. These data have greatly enhanced our understanding of the limits that various subsistence technologies set on development in other aspects of life, and of the varying probabilities that apply to the social and cultural options that fall within those limits.

In view of these changes, it is a serious mistake to suppose that contemporary evolutionary theory is simply a revival of earlier theory While the new evolutionary theory incorporates many ideas developed in the past, the basic theoretical framework differs in fundamental ways from the theories of Spencer, Tylor, and others of the past.

Why the Revival of Evolutionary Theory?

This brings us to the last of our preliminary questions: Why the revival of evolutionary theory? What makes it more attractive today than in the recent past?

A number of factors, it see...

Table of contents

• Cover Page
• Half Title page
• Title Page
• Copyright Page
• Contents
• List of Figures and Tables
• Preface
• Part I Principles
• Part II Applications
• 8 The Origins and Early Development of Ancient Israel
• 9 The Rise of the West
• 10 Trajectories of Development among Societies
• 11 An Experiment That Failed
• Part III Epilogue
• References
• Index
• List of Contributors