Investigating intentional cranial modification: A hybridized two-dimensional/three-dimensional study of the Hirota site, Tanegashima, Japan.

Intentional cranial modification has a long history, being a ubiquitous practice in many cultures around the world for millennia. The crania excavated at the Hirota site on Tanegashima Island, Kagoshima Prefecture, Japan, has been previously noted to have a marked tendency toward a short head and a flattened occipital bone, which has been suggested to be the result of artificial cranial deformation. However, whether this deformation was intentional or caused by unintentional habits remains unclear. This study aimed to investigate the characteristics of the cranial shape of the Hirota site to clarify whether the crania were intentionally modified. In the examination of Hirota crania, Kyushu Island Jomon and Doigahama Yayoi crania were added as comparative data and contrasted with three-dimensional (3D) surface scan imaging and two-dimensional outline-based geometric morphometric analysis, combined with objective assessments of potential cranial modification. The results showcased Hirota's short and flattened cranial morphology, indicating clear alignment with our hypothesis that Hirota samples are morphologically different from Doigahama and Jomon samples. No sex-based differences were found. Morphological abnormalities in cranial sutures were visually assessed utilizing novel 3D visualization methods of cranial outer surfaces. Based on a comprehensive review of the results, we concluded that Hirota site crania were intentionally modified. Although the motivation of the practice is unclear, the Hirota people may have deformed their crania to preserve group identity and possibly aid in the long-distance trade of shellfish, as seen archaeologically.

A paleopathological approach to early human adaptation for wet-rice agriculture: The first case of Neolithic spinal tuberculosis at the Yangtze River Delta of China.

The earliest evidence of human tuberculosis can be traced to at least the early dynastic periods, when full-scaled wet-rice agriculture began or entered its early developmental stages, in circum-China countries (Japan, Korea, and Thailand). Early studies indicated that the initial spread of tuberculosis coincided with the development of wet-rice agriculture. It has been proposed that the adaptation to agriculture changed human social/living environments, coincidentally favoring survival and spread of pathogenic Mycobacterial strains that cause tuberculosis. Here we present a possible case of spinal tuberculosis evident in the remains of a young female (M191) found among 184 skeletal individuals who were Neolithic wet-rice agriculturalists from the Yangtze River Delta of China, associated with Songze culture (3900-3200 B.C.). This early evidence of tuberculosis in East Asia serves as an example of early human morbidity following the adoption of the wet-rice agriculture.

An assessment of postcranial indices, ratios, and body mass versus eco-geographical variables of prehistoric Jomon, Yayoi agriculturalists, and Kumejima Islanders of Japan.

OBJECTIVES: We explore variations in body and limb proportions of the Jomon hunter-gatherers (14,000-2500 BP), the Yayoi agriculturalists (2500-1700 BP) of Japan, and the Kumejima Islanders of the Ryukyus (1600-1800 AD) with 11 geographically diverse skeletal postcranial samples from Africa, Europe, Asia, Australia, and North America using brachial-crural indices, femur head-breadth-to-femur length ratio, femur head-breadth-to-lower-limb-length ratio, and body mass as indicators of phenotypic climatic adaptation. Specifically, we test the hypothesis that variation in limb proportions seen in Jomon, Yayoi, and Kumejima is a complex interaction of genetic adaptation; development and allometric constraints; selection, gene flow and genetic drift with changing cultural factors (i.e., nutrition) and climate. METHODS: The skeletal data (1127 individuals) were subjected to principle components analysis, Manly's permutation multiple regression tests, and Relethford-Blangero analysis. RESULTS: The results of Manly's tests indicate that body proportions and body mass are significantly correlated with latitude, and minimum and maximum temperatures while limb proportions were not significantly correlated with these climatic variables. Principal components plots separated "climatic zones:" tropical, temperate, and arctic populations. The indigenous Jomon showed cold-adapted body proportions and warm-adapted limb proportions. Kumejima showed cold-adapted body proportions and limbs. The Yayoi adhered to the Allen-Bergmann expectation of cold-adapted body and limb proportions. Relethford-Blangero analysis showed that Kumejima experienced gene flow indicated by high observed variances while Jomon experienced genetic drift indicated by low observed variances. CONCLUSIONS: The complex interaction of evolutionary forces and development/nutritional constraints are implicated in the mismatch of limb and body proportions.

Differences in the effects of age on the development of entheseal changes among historical Japanese populations.

OBJECTIVE: This study aims to determine the impacts of both age and physical activity on entheseal changes at sites of muscle and ligament attachment, and proposes that the influence of age on entheseal changes may depend on specific social systems. METHODS: Entheseal markers of 193 individuals excavated from archaeological sites in Japan were examined, and archaeological evidence from those sites was used to determine the subsistence activities that those individuals engaged in. Fifteenth-century samples were either fishermen or Agehamashiki salt manufacturers, while samples from between the late 17(th) century and the 19(th) century were peasants, townspeople, or samurai. Nineteen entheses were examined using the scoring method of Hawkey and Merbs (1995) to clarify the degree to which age influenced entheseal severity of a given sample as well as the differences in the degree to which age influenced entheseal changes among samples. RESULTS: Results indicated that age influenced entheseal changes; however, the degree to which age influenced entheseal development was dependent on the characteristic physical activities associated with an individual's class and occupation. Furthermore, in certain groups, aging did not significantly impact entheseal changes. DISCUSSION: The degree to which age influenced entheseal changes was dependent on characteristic physical activities associated with an individual's class and occupation. This indicated that physical activities and lifestyle, along with age, were major factors that contributed to entheseal changes. Based on these results, it was concluded that entheseal changes could serve as a useful tool in the reconstruction of physical activities of past populations.