Mateo Peñaherrera-Aguirre

Michael Mann and Societal Aggregation: From Tribe, to Fief, to City-State, to Nation, to Empire

Written over decades, subsuming much of his career as a sociologist, Michael Mann’s four-volume Origins of Social Power pursues one grand theme: Societal aggregation from tribe, to fief, to city-state, to nation, to empire. Mann uses the term, “patterned mess,” in recognition of cultural, historical, and temporal particularities which overlay sociological laws as they have operated through time. Modern theories of gene–culture coevolution work precisely in this way, in that they operate on a fundamental level, even as surface features vary. So when Mann studies internal divisions and external competition as they ebb and flow creating regression and progression along this continuum of aggregation, it is now possible to partially explain this as a function of variation across aggregate life history continua.

Thomas Robert Malthus, Stratification, and Subjugation: Closing the Commons and Opening the Factory

With eminently unpropitious timing, Thomas Robert Malthus wrote of resource competition just as humans were bursting the bonds of organic economies. An Essay on the Principle of Population, in warning of the ills consequent to population density and resultant resource competition, may have, however, underappreciated its evolutionary effects. Although the significance of mortality regime has superseded its overall significance, population density, and the resource competition it brings, was the variable around which life history theory was originally constructed. With the coming of density and accompanying competition, life history theory explains how populations change and stratify as they vie to survive and reproduce. As herein argued, the slowing of life history is a consequence of population density that Malthus could not suspect, but might have appreciated.

Arnold Joseph Toynbee: The Role of Life History in Civilization Cycling

Where Edward Gibbon studied the Decline and Fall of Rome, Arnold Toynbee more generally studied the decline and fall of civilizations. The civilizational challenge is followed by a creative and adaptive response, or otherwise conquest and collapse. Across all studied civilizations, Toynbee returns to the theme of internal cohesion and its relation to external competition. In doing so, Toynbee touched upon some universal truths that underlie the cyclical view of history, though he emphasized the spiritual and circumstantial to the detriment of the geographical and biological. Nevertheless, Toynbee’s insights can be productively reinterpreted with life history evolution, such that his valid universal insights are qualified by particular inter-population variation, which ultimately chains cultural decline to its biological substrates.

Richard Price: The Schedules of Mortality

Two centuries ago, Richard Price assisted in compiling the Northampton Tables, allowing lives to be insured with probabilistic rationality. This was part of a life’s work concerning the measurement of mortality risk. Though such early demographic investigations gained predictive power, explanatory power lagged behind. Herein we reread Price’s work on mortality risk using life history evolution, which, after all, is organized around mortality and longevity, making it an invaluable aid in understanding the actuarial life table. As can only be explained at length, it is apparent that Price, in measuring mortality, was indirectly measuring life history; and in applying his researches to life insurance, was in effect facilitating post-mortem parental care.

Urie Bronfenbrenner: Toward an Evolutionary Ecological Systems Theory

Through his Bioecological Systems Theory, Urie Bronfenbrenner emphasized school, parish, neighborhood, and other aspects of what behavioral geneticists now call the extra-familial environment. Bronfenbrenner incorporated even the economy, government, and culture into his developmental scheme, knowing that these macrostructural realities trickle-down to influence more local systems, if not the child directly. As recounted in this chapter, life history theorists have extended ecological systems theory such that it incorporates natural ecological systems, not limited to temperature, humidity, parasite prevalence, resource availability, and population density. An evolutionary view of Bronfenbrenner’s Ecological Systems Theory then clarifies the extent and direction of influences, while also adding a basement layer of natural ecology that constrains all other levels of influence.

Raymond B. Cattell: Bequeathing a Dual Inheritance to Life History Theory

Raymond Cattell distinguished crystallized intelligence, akin to stored knowledge, from fluid intelligence, akin to raw reasoning abilities. Likewise, he delineated personality into component parts. Though intelligence and personality each qualify as subdisciplines within psychology, both are subsumed, along with other traits, under the meta-theory of life history evolution. The relationship is profound, though not straightforward. As described in this chapter, both intelligence and personality vary along a life history continuum, such that, as life history slows, population mean intelligence increases, as do personality traits like risk aversion, conscientiousness, anxiety, and agreeableness. Nevertheless, this effect occurs on average, and there is strategic variation occurring, which obscures the relationship between population-mean intelligence, personality, and life history. Once understood, these relationships color and clarify Cattell’s life’s work.

The Baron de Montesquieu: Toward a Geography of Political Culture

Montesquieu incorporates what would now be understood as political science and ecology into his eighteenth-century sociological studies. He concluded that sociopolitical systems were outgrowths of ecological conditions, and so cannot be unthinkingly transplanted from locale to locale. Already extant, there are evolutionarily informed studies of Montesquieu’s thesis using variables such as group-mean intelligence, which validates the relation between ecology and the development of monarchies, republics, and despotisms. However, this fourteenth chapter shows that this is but a part of a larger process. Human populations respond to ecological conditions through changes in mean intelligence, but also through changes in other life history traits. Consequently, it is inter-population life history means that were obliquely observed by Montesquieu to give rise to sociopolitical differences.

Marvin Harris: Ecological Anthropology and Cultural Materialism

Marvin Harris has taken the vagaries of culture and grounded them in ecology. From burning witches, to worshiping animals, to proscribing foods, Harris finds religious and cultural idiosyncrasies to proceed from ecological vagaries. More than this, Harris broaches social structure, demographic constraint, race, death, sex, and fertility, all of which are traced back to some knowable ecological determinant from which they probabilistically derive. Yet, like Keeley, Harris pointedly rejects sociobiological explanations. He believed evolutionary explanations of cultural differences to be impossible, insufficient, and unnecessary. As herein explained, these assumptions stem from a misunderstanding of how rapidly populations can evolve, unfamiliarity with life history theory and related sociobiological explanations that explain intraspecific diversity, and overconfidence in phenotypic plasticity and environmental explanation more generally.

William H. McNeill: Epidemiological and Biogeographical Perspectives on Civilization

Like Toynbee, William McNeill is a world historian, but one with a bent toward epidemiology. Most directly in his Plagues and Peoples, McNeill considers the role of disease-induced mortality, infection, and transmission alongside the more traditional historical topics of war and conquest. McNeill studied disease as a primary cause in its own right, rather than as incidental sequelae to climatological catastrophes, famine, war, or resource limitation. McNeill anticipates the emphasis placed by modern evolutionary life history theory upon regimes of extrinsic mortality as being the main drivers shaping life history evolution. After all, from its founding, life history has incorporated population density and mortality rates into its quantitative formulae and qualitative theory, making it an ideal framework from which to reconsider McNeill.

Lawrence H. Keeley: Pre-state Societies in the Hobbesian Trap

Lawrence Keeley was at the forefront of scientifically deciding between Rousseau, who saw civilization as corrupting noble savages and peaceable peoples, and Hobbes, who saw a war of all against all waged between peoples, clans, and tribes except if dominated by a Leviathan capable of monopolizing power and violence. Keeley came down firmly on the side of Hobbes, demonstrating the rampant violence and persistent warfare of pre-state societies. In the absence of life history theory, Keeley, and anyone else studying declining violence through modernity, is reduced to positing a host of explanations piecemeal, and thereafter finding it difficult to explain the positive feedback effect wherein decreasing violence, begets decreasing violence. Keeley explicitly abjures biological explanations of violence; a point directly addressed as this twelfth chapter evolutionarily interprets his findings.