Intensive Agriculture and Socio-Political Development in the Lake Patzcuaro Basin, Michoacan, Mexico

Article excerpt


Intensive agriculture played a pivotal role in the development of archaic states, but there is considerable debate concerning its relationship to population growth, climatic variability, and centralization. One important example is that of the Tarascan State (Lake Patzcuaro Basin, Michoacan, Mexico (Pollard 1997) [ILLUSTRATION FOR FIGURE 1 OMITTED].

Newly discovered intensive wetland features, in the form of canals and associated agricultural fields, allow the intensification question to be assessed in this region for the first time. This new research examines the relationship between intensification, demography, environmental variability, and the emergence of social complexity for the pre-Tarascan period. Relict agricultural features are an amalgam of socio-economic process and landscape manipulation requiring multiple lines of archaeological and environmental data to decode. This synthesis is best accomplished through a landscape approach.

Intensification in perspective

Two types of intensification approaches can be defined based on core assumptions [ILLUSTRATION FOR FIGURE 2 OMITTED]. The first, the top down and the bottom up type of approach (Chambers 1980; Erickson 1993a; Scarborough 1991) debates who, and with what resources, was able to construct water-management features. The more traditional and most often applied top down approach, following the hydraulic hypothesis (Wittfogel 1957), suggests that the complexity, large scale, technological sophistication and massive labour requirements of intensive agriculture require co-ordination, planning, management and possibly coercion, most often by the state (Kolata 1996; Matheny & Garr 1983; Sanders et al. 1979; Stanish 1994). In this view, only state-level societies are capable of absorbing the presupposed high labour, capital, and administrative costs.

Recent archaeological research has come to re-examine the top down approach. Excavation and survey within the Lake Titicaca Basin (Erickson 1993a; Graffam 1992) has identified extensive tracts of raised fields and associated settlements that can be securely dated to periods that precede and post-date regional integration by the Tiwanaku state. These systems also initially evolved and persisted in the absence of population or other stresses. Raised-field and canal systems have also been located prior to regional integration contexts in other areas of Latin America (Doolittle 1990; Sluyter 1994). This has led Erickson to argue that raised-field farming was organized locally, producing, over time, a totally human-made landscape (1993a: 371).

The second type of approach is composed of explanations emphasizing differing evolutionary mechanisms for the adoption of agricultural intensification. Either a prime mover (push) or political economy (pull) based approach provides the impetus for intensification. The push-based mode assumes that prehistoric farmers participate in a labour-intensive mode of subsistence as a response to some sort of resource imbalance, most often demographic. Thus, in this prime-mover-orientated approach, population pressure (Boserup 1981; Sanders et al. 1979; Turner et al. 1977), becomes an evolutionary mechanism that is seen as a prerequisite for intensive agricultural systems. In recent literature the systemic relationship between population growth and agricultural intensification first proposed by Boserup (1965) has been critically examined. As a result there is a growing body of archaeological literature that suggests the lack of a causal link between demographic stress and agricultural intensification (e.g. Blanton et al. 1982; Brumfiel 1976; Feinman et al. 1985; Kowalewski et al. 1989).

Political-economy-based explanations assert that intensification is a response to socio-economic systems promoting predictable surplus to facilitate kin-based exchange, risk management, craft specialization and lineage-based demands for tribute (Brumfiel & Earle 1987; D'Altroy & Earle 1985; Price & Feinman 1995; Wright 1984). …