The Ecological-Evolutionary Typology of Human Societies and the Evolution of Social Inequality

The Ecological-Evolutionary Typology of Human Societies and the Evolution of Social Inequality

François Nielsen

Department of Sociology

University of North Carolina

Chapel Hill

June 2002

Address all correspondence to François Nielsen, Department of Sociology, University of North Carolina, Chapel Hill NC 27599-3210. Phone [phone]. Fax [phone]. Email [e-mail]. Web site at www.unc.edu/~nielsen/. This paper is submitted as a possible chapter in a collection of essays in honor of Gerhard Lenski edited by Bernice McNair Barnett.

1Introduction

The purpose of this paper is to investigate the usefulness of Gerhard Lenski's influential typology of human societies in tracking the evolution of various dimensions of social inequality. Themes developed in this paper include the following.

First, Lenski's ecological-evolutionary typology of human societies is a powerful empirical predictor of evolutionary patterns in a number of dimensions of social inequality.

Second, despite its explanatory power it is a truly exogenous typology, i.e., it is based entirely on variables describing the infrastructure of a society (i.e., the level of technology and the nature of the physical environment), rather than on variables describing the superstructure (e.g., the type of political organization) as are the traditional typologies of Service (1962, 1975) and Fried (1967). Put another way, Lenski's typology is constructed from independent variables and thereby differs from traditional typologies constructed from dependent variables. Thus the ecological-evolutionary typology is inherently causal, rather than purely descriptive.

Third, even though the best comparative data sets measure a number of dimensions of stratification systems, it is surprisingly difficult to find a measure that represents a quantitative summary of the overall degree of inequality, or unequal access to resources, power, and privilege in a society; one measure that comes close to that requirement and that has been overlooked in previous research is the degree of sexual and reproductive inequality among men, as it may be measured by the extent to which powerful men monopolize women as wives for themselves. This measure of inequality also constitutes a direct link between human social inequality and dominance hierarchies elsewhere in the animal world.

Fourth, comparative analyses of available measures of the development of stratification systems provide clues suggesting that Lenski's summary view of the evolution of social inequality may have to be somewhat modified. I will show that for some dimensions of social inequality the nadir of human freedom may be associated with the advanced horticultural type of society, rather than with the advanced agrarian type as Lenski had conjectured. Such "agrarian reversals" in monotonic inequality trends have important empirical and theoretical implications for understanding the evolution of social inequality.

2Gerhard Lenski's Typology of Human Societies

2.1Historical

The motivation for constructing the ecological-evolutionary typology of human societies is outlined in Power and Privilege (Lenski 1966:90-93). In the earlier part of the work Lenski develops a general theory of stratification based on the premise that the level and mode of technology are a major influence on stratification systems. Thus, he argues, to examine distributive systems across societies it is natural to use a typology of societies based on technological criteria: "Since it is predicted that technological variation is the primary determinant of variations among distributive systems, societies should be classified in technological terms, and this scheme of classification should be used to order the presentation of data" (p. 90). He goes on to trace the origins of the typology he is about to propose to early anthropologist Lewis Henry Morgan (1877) and archaeologist V. Gordon Childe (1936), among others, but the most immediate influence is the typology proposed by Goldschmidt (1959). Goldschmidt's scheme, in which societies are classified according to level of technological advance, is a close forerunner of Lenski's (compare Figure 3 and Figure 4 in Lenski 1966:92). Lenski modifies Goldschmidt's typology by subdividing horticultural societies into a simple and an advanced type, adding categories for fishing and maritime societies, and merging together into a single type hunting and gathering societies, that Goldschmidt had subdivided into nomadic and settled. While Lenski is well aware of the early work of Elman Service (1962), he does not mention Service's classificatory work as an influence; Fried (1967) and Service (1975) were published after Power and Privilege (1966) and could not have influenced the latter. Thus Lenski's typology was proposed independently of some of the most popular classificatory schemes in use today (see also Diamond 1998:268-269). Revised versions of the ecological-evolutionary typology were published in successive editions of Human Societies (Lenski 1970; Nolan and Lenski 1999).

2.2Ecological-Evolutionary Typology

While the term ecological-evolutionary may sound at first like the creation of a slick promoter trying to combine two fashionable terms into an irresistible package, it in fact describes closely the principle of the typology. Lenski's typology is indeed based on the combination of an evolutionary dimension of technological advance and an ecological dimension of environmental variation.

2.2.1Evolutionary Dimension

The evolutionary dimension refers to the level of technological advance. Each technological level is linked to one crucial technological innovation. Thus Lenski postulates what is in effect a Gutman scale of technological innovations, such that each new innovation marking the passage to a more advanced level presupposes all the earlier innovations. Each innovation marks the advent of a more advanced type of society in the "normal environment" (i.e., parts of the world where farming is feasible), forming what may be called the "main sequence" of socio-cultural evolution (although Lenski himself does not use this terminology). The main sequence consists of the following types:

• 
  hunting and gathering societies (primordial type)
  

• 
  simple horticultural societies, characterized by farming using simple tools (hoe and digging stick) – appear about 8,000 BCE
  
• 
  advanced horticultural societies, characterized by metallurgy of copper and bronze
  
• 
  simple agrarian societies, characterized by the use of the plow – appear about 3,000 BCE
  
• 
  advanced agrarian societies, characterized by iron metallurgy
  
• 
  industrial societies, characterized by the use of machines powered by inanimate forms of energy – appear about 1750 CE
  

It is clear that Lenski considers the level of technology the primary dimension of the typology. For example in Power and Privilege he writes:

The present typology is predicated on the assumption that there is an underlying continuum, in terms of which all societies can be ranked. This continuum is a measure of a society's overall technological efficiency, i.e., the value of a society's gross product in international markets divided by the human energy expended in its production. Unfortunately, this concept is not easily operationalized, and we are forced to rely on simpler and more obvious criteria for classificatory purposes. This is the reason for classifying societies in terms of their basic techniques of subsistence. Such data are readily available and seem highly correlated with overall technological efficiency. (Lenski 1966, p. 93)

We will see later that in Lenski's thinking technological efficiency does not "exhausts" the effects of a particular mode of subsistence on systems of stratification. The mode of subsistence can affect distributive system through paths others than efficiency of production.

2.2.2Ecological Dimension

The main sequence is limited to environments in which plow cultivation is feasible. Environments too arid for plow-based farming, or that present alternative subsistence opportunities because of proximity to large bodies of water, will support societies based on different subsistence strategies.

• 
  herding societies subsist by herding livestock in arid environments where plant cultivation is not practical
  
• 
  fishing societies subsist by fishing in environment with easy access to suitable bodies of water
  
• 
  maritime societies use their proximity to large bodies of water to derive their subsistence from maritime trade
  

2.2.3Combining Ecological and Evolutionary Dimensions

Combining the two dimensions yields the typology, which can be represented as in Figure 2.1 (modified from a figure in earlier edition of Human Societies).
------ Figure 2.1 about here ------
The figure shows the main sequence toward the center, with the specialized societies symbolically situated to the left and right of the horizontal axis at corresponding levels of technological development.