Health in late prehistoric Thailand

Abstract

The aim of this research was to provide a synthesis of the variations in health among prehistoric Thai communities, and to show that the health of these people was differentially affected by both their natural and cultural environment. Four skeletal samples comprising a total of 500 skeletons provided the material for this research. There were two coastal southeastern skeletal samples, Khok Phanom Di (2000-1500 BC, early agriculture) and Nong Nor (1100-700 BC, Bronze Age) and two inland northeastern samples, Ban Lum Khao (1400 BC, Bronze Age) and Ban Na Di (600-400 BC, Iron Age). It was hypothesised that the health profile of samples from within the same natural environment would be similar and, conversely, that the health status of the northeast would be in contrast to the southeast. Additionally, it was hypothesised that changes in the cultural environment through time, including the intensification of rice agriculture, would see an improvement in general health.

Health, morbidity, and mortality were investigated through the analysis of a selection of parameters that included measures of mortality, growth and its disturbances, joint disease, trauma, and dental health. This selection, although not exhaustive, enabled a representation of the health status of the four samples to be obtained and compared. Using a biocultural approach this information has been integrated with archaeological and ethnographic evidence for nutrition, pathogen load, and culture, to determine the effect each natural and cultural environment had on community health.

Within the southeast region there were marked differences between the health profiles of the Khok Phanom Di and Nong Nor samples. Nong Nor had lower subadult mortality, taller adult statures and lower prevalences of dental pathologies. However, skeletal preservation was poor at Nong Nor and not all parameters were able to be observed. Within the northeastern samples health profiles were similar in overall prevalences of joint disease and dental health, but childhood morbidity and mortality were different. The latter, measured through observations of infant mortality, enamel hypoplasia and adult stature, were higher at Ban Lum Khao than at Ban Na Di. The natural environment had a significant influence on the health status of the people studied but not in the manner hypothesised. Comparisons within and between regions were complicated by time differences that may have affected the people's ability to cope with their environment. The comparatively poorer health suffered by the Khok Phanom Di and Ban Lum Khao communities may have been related to their settlement and adjustment to potentially new environments. In contrast, it is likely that both the Nong Nor and Ban Na Di communities were familiar with their natural environments as they were not the first settlers in their respective regions.

With respect to the cultural hypothesis, results indicated that a general improvement in health had occurred through the time periods studied. The earliest sample, the people of Khok Phanom Di, were the least healthy. They had comparatively high prevalences of dental pathologies and joint disease, and high subadult mortality and morbidity, the latter reducing the attained adult stature. Health improved into the Bronze Age, particularly so in the Nong Nor sample, the people of which had low subadult mortality and tall statures compared with the Ban Lum Khao sample. However, poor preservation of the Nong Nor skeletal material places a caveat over any interpretation. The people of the early Iron Age at Ban Na Di continued the trend for improving health. They had moderate subadult mortality and morbidity, although as they reached tall statures these had limited effects. In addition, dental health improved and osteoarthritis decreased with time. Post-Iron Age, Thai people underwent an expansion of society led by the establishment of the centralised political regime of the Angkorian civilisation. From this selective view of skeletal health it appears the people were healthy enough to withstand the effects of such a transition. Further integration with other prehistoric Southeast Asian skeletal samples is now required to support this statement.