Revisiting traumatic injury risk and agricultural intensification: Postcranial fracture frequency at Cerro Oreja in the Moche Valley of north coastal Peru.

OBJECTIVES: In Lambert and Welker (2017) we explored the association between subsistence economy and postcranial fracture prevalence, finding that low-intensity agriculturalists exhibited significantly lower fracture rates than foragers or high-intensity agriculturalists. Here, we explore the impacts of sampling strategy on fracture rates in a sample of high-intensity agriculturalists from the Moche Valley, Peru, and further test the hypothesis that postcranial fracture risks are higher for intensive agriculture. MATERIALS AND METHODS: The long bones and clavicles of 102 individuals from an Early Intermediate Period cemetery (400 B.C.-A.D. 200) at Cerro Oreja were examined for healed fractures. Sample composition was manipulated in six ways to investigate the effects of age and element completeness on estimates of fracture prevalence. Fracture rates at Cerro Oreja were then compared to those for other high-intensity agriculturalists. RESULTS: Both skeletal element completeness and age composition were found to influence fracture rate estimates, reflecting the greater likelihood of identifying healed fractures on better-preserved bones and the accrual of injuries with age. The fracture rate of 3.4% at Cerro Oreja was the median value among seven high-intensity agriculturalist samples. The fracture distribution at Cerro Oreja was most similar to that observed at Kulubnarti, Sudan (Kilgore et al., 1997). DISCUSSION: Skeletal element completeness and age composition can impact fracture rates estimated for skeletal samples and should be considered when conducting comparative analyses. All rates calculated for Cerro Oreja are within the range of those obtained for other high-intensity agriculturalists and support previous findings that traumatic injury risk is higher for high-intensity agriculturalists. Similarities between Cerro Oreja and Kulubnarti suggest that rugged terrain may exacerbate fracture risk for agriculturalists, illustrating the costs of intensive agriculture in suboptimal environments.

Traumatic injury risk and agricultural transitions: A view from the American Southeast and beyond.

OBJECTIVES: Bioarchaeological research has documented a general decline in health with the transition from foraging to farming, primarily with respect to changing patterns of morbidity. Less is known about changes in injury risk, an aspect of health more obviously tied to particular landscapes and behaviors associated with different subsistence regimes. The purpose of this research is to evaluate several hypotheses emerging from the ideal free distribution model (Fretwell & Lucas, ) that predict injury risk based on subsistence-specific practices and land use patterns. MATERIALS AND METHODS: Postcranial fracture frequencies for long bones and clavicles in human skeletal remains from three Southeast U.S. regions permit examination of variability in injury risk among low-intensity (floodplain) farmers. Published data on six hunter-gatherer samples, four low-intensity agriculturalist samples, and six high-intensity agriculturalist samples comprise a comparative sample for examining variability in injury risk across three distinct subsistence traditions. Differences are evaluated using Z scores and the Fisher Exact test, Chi-Square test, and Mann-Whitney U test. RESULTS: While statistically significant differences are apparent among low-intensity farming groups in the Southeast sample, in the global comparison postcranial fractures are significantly less common in low-intensity agriculturalists than in hunter-gatherers or high-intensity agriculturalists. DISCUSSION: The results of this study support the hypothesis that, with respect to traumatic injury risk, low-intensity farming is a risk-averse subsistence strategy in comparison with full-time foraging or high-intensity agriculture. These data suggest that it is not agriculture per se that predicts an increase in this health risk, but rather the mode and intensity of agricultural production, findings that have important ramifications for our understanding of the health consequences of major subsistence transitions.

Sociopolitical effects of bow and arrow technology in prehistoric coastal California.

Bow and arrow technology spread across California between ∼AD 250 and 1200, first appearing in the intermountain deserts of the Great Basin and later spreading to the coast. We critically evaluate the available data for the initial spread in bow and arrow technology and examine its societal effects on the well-studied Northern Channel Islands off the coast of Southern California. The introduction of this technology to these islands between AD 650 and 900 appears to predate the appearance of hereditary inequality between AD 900 and 1300. We conclude, based on the available data, that this technology did not immediately trigger intergroup warfare. We argue that the introduction of the bow and arrow contributed to sociopolitical instabilities that were on the rise within the context of increasing population levels and unstable climatic conditions, which stimulated intergroup conflict and favored the development of hereditary inequality. Population aggregation and economic intensification did occur with the introduction of the bow and arrow. This observation is consistent with the hypothesis that social coercion via intra-group "law enforcement" contributed to changes in societal scale that ultimately resulted in larger groups that were favored in inter-group conflict. We argue that the interplay between intra-group "law enforcement" and inter-group warfare were both essential for the ultimate emergence of social inequality between AD 900 and 1300.

Health versus fitness: competing themes in the origins and spread of agriculture?

The general picture of human health that has emerged from bioarchaeological studies of the agricultural transition is one of health decline, although the nature and severity of the biological impacts have varied in accordance with worldwide diversity in the timing, duration, and specific characteristics of this economic shift. Conversely and somewhat paradoxically, the emerging picture has also been one of enhanced fertility and population growth. These findings raise challenging questions about the measures bioarchaeologists use to assess the biological costs and benefits of agriculture. It is argued here that these measures fall into two potentially quite distinct categories-physiological fitness (homeostasis) and reproductive (Darwinian) fitness, measures that may assess the costs and benefits of a biocultural system very differently. Both provide valuable insights into questions about our past at levels ranging from the evolution of our species to the unique experiences of individuals and their kin. However, the relative importance of each in larger questions about human adaptation needs to be carefully considered when assessing the biological evidence in questions of causation.

Infectious disease among enslaved African Americans at Eaton's Estate, Warren County, North Carolina, ca. 1830-1850

The skeletal remains of 17 people buried in the Eaton Ferry Cemetery in northern North Carolina provide a means of examining health and infectious disease experience in the XIX century South. The cemetery appears to contain the remains of African Americans enslaved on the Eaton family estate from approximately 1830-1850, and thus offers a window into the biological impacts of North American slavery in the years preceding the Civil War. The sample includes the remains of six infants, one child, and one young and nine mature adults (five men, four women, and one unknown). Skeletal indices used to characterize health and disease in the Eaton Ferry sample include dental caries, antemortem tooth loss, enamel hypoplasia, porotic hyperostosis, periosteal lesions, lytic lesions, and stature. These indicators reveal a cumulative picture of compromised health, including high rates of dental disease, childhood growth disruption, and infectious disease. Specific diseases identified in the sample include tuberculosis and congenital syphilis. Findings support previous research on the health impacts of slavery, which has shown that infants and children were the most negatively impacted segment of the enslaved African American population.

Infectious disease among enslaved African Americans at Eaton's Estate, Warren County, North Carolina, ca. 1830-1850.

The skeletal remains of 17 people buried in the Eaton Ferry Cemetery in northern North Carolina provide a means of examining health and infectious disease experience in the XIX century South. The cemetery appears to contain the remains of African Americans enslaved on the Eaton family estate from approximately 1830-1850, and thus offers a window into the biological impacts of North American slavery in the years preceding the Civil War. The sample includes the remains of six infants, one child, and one young and nine mature adults (five men, four women, and one unknown). Skeletal indices used to characterize health and disease in the Eaton Ferry sample include dental caries, antemortem tooth loss, enamel hypoplasia, porotic hyperostosis, periosteal lesions, lytic lesions, and stature. These indicators reveal a cumulative picture of compromised health, including high rates of dental disease, childhood growth disruption, and infectious disease. Specific diseases identified in the sample include tuberculosis and congenital syphilis. Findings support previous research on the health impacts of slavery, which has shown that infants and children were the most negatively impacted segment of the enslaved African American population.

Rib lesions in a prehistoric Puebloan sample from southwestern Colorado.

An unusually high frequency of periosteal lesions of visceral rib surfaces was observed in a small, prehistoric skeletal series from southwestern Colorado. Lesions of this type have been concordant with pulmonary tuberculosis in three studies of human skeletal collections with known cause of death, and in a recent clinical investigation of rib dimensions in living patients with lung disorders. Diseases such as pneumonia and actinomycosis have also been found to cause these lesions, but in much lower frequencies. Archaeological evidence suggests that Puebloan farmers of Sleeping Ute Mountain's southern piedmont, from which the sample is drawn, endured unusually harsh environmental conditions punctuated by severe drought and exacerbated by escalating warfare. It is argued here that these environmental stressors increased susceptibility to an opportunistic respiratory infection reminiscent of tuberculosis, and possibly also some form of pneumonia, resulting in high rates of active disease previously noted only in historic Puebloan peoples.