Adoption Of Maize Agriculture Research Articles

When does it pay to invest in a patch? The evolution of intentional niche construction

Humans modify their environments in ways that significantly transform the earth's ecosystems. Recent research suggests that such niche-constructing behaviors are not passive human responses to environmental variation, but instead should be seen as active and intentional management of the environment. Although such research is useful in highlighting the interactive dynamics between humans and their natural world, the niche-construction framework, as currently applied, fails to explain why people would decide to modify their environments in the first place. To help resolve this problem, we use a model of technological intensification to analyze the cost-benefit trade-offs associated with niche construction as a form of patch investment. We use this model to assess the costs and benefits of three paradigmatic cases of intentional niche construction in Western North America: the application of fire in acorn groves, the manufacture of fishing weirs, and the adoption of maize agriculture. Intensification models predict that investing in patch modification (niche construction) only provides a net benefit when the amount of resources needed crosses a critical threshold that makes the initial investment worthwhile. From this, it follows that low-cost investments, such as burning in oak groves, should be quite common, while more costly investments, such as maize agriculture, should be less common and depend on the alternatives available in the local environment. We examine how patterns of mobility, risk management, territoriality, and private property also co-evolve with the costs and benefits of niche construction. This approach illustrates that explaining niche-constructing behavior requires understanding the economic trade-offs involved in patch investment. Integrating concepts from niche construction and technological intensification models within a behavioral ecological framework provides insights into the coevolution and active feedback between adaptive behaviors and environmental change across human history.

Evolution of Chilia lobes of the Danube delta: Reorganization of deltaic processes under cultural pressures

The growth of Chilia deltaic lobes reflects a drastic reorganization of the Danube delta that accompanied its rapid expansion in the late Holocene. Using new cores collected at the apices of the two older Chilia lobes, together with historical maps and satellite photos, we find that a partial avulsion since ∼1500 years BP led to a gradual rejuvenation of the Chilia distributary. This process led to the successive infilling of a lake and a lagoon and subsequently to the construction of an open coast lobe at the Black Sea coast. The Chilia branch became the largest Danube distributary, reaching its maximum sediment load in the last 300 years as the southernmost St. George branch lost its previous dominance. Here, we propose that the intensive deforestation of Danube's lower watershed leading to this delta reorganization has historical cultural causes: an increase in sheep and timber demand associated to the Ottoman Empire expansion in Eastern Europe followed by the adoption of maize agriculture as a result of the Columbian Exchange. Rapid industrialization-driven damming during the Communist Era led to the current generalized sediment deficit for the Danube. Under these conditions, the modern Chilia lobe is rapidly remodeled by waves and may join the Sulina coast to impede navigation on the Sulina canal.

Synchronous environmental and cultural change in the prehistory of the northeastern United States

Climatic changes during the late Quaternary have resulted in substantial, often abrupt, rearrangements of terrestrial ecosystems, but the relationship between these environmental changes and prehistoric human culture and population size remains unclear. Using a database of archaeological radiocarbon dates alongside a network of paleoecological records (sedimentary pollen and charcoal) and paleoclimatic reconstructions, we show that periods of cultural and demographic change in the northeastern United States occurred at the same times as the major environmental-climatic transitions of that region. At 11.6, 8.2, 5.4, and 3.0 kyr BP (10(3) calendar years before present), changes in forest composition altered the distribution, availability, and predictability of food resources which triggered technological adjustments manifested in the archaeological record. Human population level has varied in response to these external changes in ecosystems, but the adoption of maize agriculture during the late Holocene also resulted in a substantial population increase. This study demonstrates the long-term interconnectedness of prehistoric human cultures and the ecosystems they inhabited, and provides a consolidated environmental-cultural framework from which more interdisciplinary research and discussion can develop. Moreover, it emphasizes the complex nature of human responses to environmental change in a temperate region.

Regional Variation in the Pattern of Maize Adoption and Use in Florida and Georgia

Dietary reconstruction using carbon and nitrogen stable isotopes from archaeological human bone samples from coastal Georgia and northern and Gulf Coast Florida dating between 400 B.C. and A.D. 1700 serves to illustrate the complexity of the agricultural transition in that region. Isotope analysis of 185 collagen samples drawn from early prehistoric, late prehistoric, and contact-period mortuary sites encompasses two major adaptive shifts in the region, namely the adoption of maize agriculture in late prehistory and the increased emphasis on maize during the mission period. Prior to European contact—and especially before the establishment of Spanish missions among the Guale, Yamasee, Timucua, and Apalachee tribal groups—diet was strongly influenced by local environmental factors. Before contact, coastal and inland populations had different patterns of food consumption, as did populations living in Georgia and Florida. Coastal populations consumed more marine and less terrestrial foods than inland populations. In general, maize was adopted during the eleventh century A.D. by virtually all Georgia populations. However, with the exception of the Lake Jackson site, a major Mississippian center in northern Florida, Florida populations show little use of maize before contact. Following European contact, maize became wide-spread, regardless of location or habitat within the broad region of Spanish Florida. Missionization appears to have been an important factor in the convergence of native diets toward agriculture and away from foraging. This increased emphasis on maize contributed to a decline in quality of life for native populations.

Oxygen Isotopic Analysis of Archaeological Shells to Detect Seasonal Use of Wetlands on the Southern Pacific Coast of Mexico

Oxygen isotopic ratios in modern and archaeological marsh clam shells ( Polymesoda radiata) from the Acapetahua Estuary in southwestern Mexico record large scale salinity fluctuations caused by alternating wet and dry seasons. Thus, prehistoric patterns of rainfall can be reconstructed and the season of molluscan death can be estimated. Changes in the oxygen isotopic patterns preserved in marsh clam shells from late Archaic period ( c. 3000–1800 bc) archaeological deposits indicate that the season of shellfish harvesting changed dynamically through time in this region. Based on this study, and other lines of archaeological evidence, we argue that hunter–gatherers during the early stages of the late Archaic period visited locations in the littoral zone throughout the year with a focus during dry season months. Through the late Archaic period a general trend occurred toward wet season use of these locations. This culminated at the end of the late Archaic period with the exclusive use of the littoral zone during wet season months. These data indicate a fundamental shift in the way these estuarine locations were being used. We argue that people living in this region altered their overall subsistence strategy during the late Archaic period due to scheduling conflicts that occurred with the adoption of maize agriculture.

Dental Paleopathologies in the Sanders Site ( 41LR2) Population from Lamar County, Texas

Dental health, like skeletal health, reflects the natural and social environment, as well as genetics. This paper focuses on the results of stress on the teeth once they have erupted; stresses include chemical, mechanical, and pathogenic forces. These forces are primarily the result of dietary factors. The specific aspects of dental health examined in this paper are cariogenesis, dental attrition, antemortem tooth loss, and abscessing. These dental paleopathologies primarily reflect diet and food processing strategies. Throughout the Americas, dental disorders have increased with the adoption of maize agriculture. Reliance on maize provides a sticky, carbohydraterich dietary staple that is favorable to microbial attack. Maize cultivation has been ... correlated with an increase in caries and abscess frequency. Poor dental health also may directly impact general physical health. Periodontal disease often results in gingival inflammation, abscessing, and tooth loss. Lesions in the mouth can be the port of entry for pathogens, such as staphylococci and streptococci, that may then travel to other parts of the body. Dental attrition is not considered a disorder in this paper, but the natural result of a diet high in unprocessed vegetal materials and grit. Grit is introduced into the diet from a variety of means, but I will focus on the introduction of grit through stone grinding implements. Sand particles can also result in a considerable amount of attrition. Dental attrition can, however, lead to pathologies if the pulp cavity is exposed. In this case, the pulp cavity may serve as the focus of infection, resulting in abscessing and eventual tooth loss. Dental health is thus largely dependent on dietary factors. The examination of dental health is useful in reconstructing nutritional behaviors. It will be seen in this examination of the teeth that the maize agriculturalists at the Sanders site were primarily affected by a high frequency of caries. Other factors examined (moderate dental enamel attrition, slight antemortem tooth loss, and slight abscessing) suggest that dietary behaviors were not as detrimental to the Sanders population as has been noted for other maize-dependent agricultural groups. If nutrition was related to status among Caddoan groups, this may be the result of the assumed high status of the individuals interred at the Sanders site, since all the individuals were interred in a mound context.

Histological enamel indicator of childhood stress in prehistoric skeletal samples

Although previous paleopathological studies have used disturbances in enamel formation as indicators of childhood stress, the full potential of this technique has not been realized. This paper presents a test case which demonstrates that the frequency of disturbed enamel formation (i.e., Wilson bands) is associated with other stress indicators (i.e., probability of dying and infectious lesions) in three prehistoric skeletal samples representing the Middle Woodland (10.3%), Mississippian Acculturated Late Woodland (21.4%), and the Middle Mississippian (40.0%). Additionally, the mean ages at death of individuals with at least one Wilson band are lower than those without bands. These results suggest that Wilson bands are an indicator of the relative proportion of individuals who are high susceptibles in prehistoric populations. The data also corroborate the hypothesis that the adoption of maize agriculture in the prehistoric American Midwest is associated with increased stress.