Mobility, exchange, and tomb membership in Bronze Age Arabia: A biogeochemical investigation

Major transitions in subsistence, settlement organization, and funerary architecture accompanied the rise and fall of extensive trade complexes between southeastern Arabia and major centers in Mesopotamia, Dilmun, Elam, Central Asia, and the Indus Valley throughout the third and second millennia BC. I address the nature of these transformations, particularly the movements of people accompanying traded goods across this landscape, by analyzing human and faunal skeletal material using stable strontium, oxygen, and carbon isotopes. Stable isotope analysis is a biogeochemical technique utilized to assess patterns of residential mobility and paleodiet in archaeological populations. Individuals interred in monumental communal tombs from the Umm an-Nar (2500-2000 BC) and subsequent Wadi Suq (2000-1300 BC) periods from across the Oman Peninsula were selected, and the enamel of their respective tomb members analyzed to detect (a) how the involvement of this region in burgeoning pan-Gulf exchange networks may have influenced mobility, and (b) how its inhabitants reacted during the succeeding economic collapse of the early second millennium BC.;Due to the commingled and fragmentary nature of these remains, the majority of enamel samples came from a single tooth type for each tomb (e.g., LM 1) to prevent repetitive analysis of the same individual. However, in a few instances, multiple in situ teeth were present and permitted inter-tooth sampling as a means of evaluating temporal shifts in mobility and diet within the lifetime of single individuals.;Stable strontium and oxygen ratios indicate that the Umm an-Nar inhabitants of southeastern Arabia were not highly mobile despite their increasing involvement in regional and interregional trade. However, such patterns do fit with archaeological evidence for an increasingly sedentary lifestyle associated with intensified oasis agriculture and the construction of large, permanent settlements and fortification towers. Non-local immigrants were interred in small numbers within Umm an-Nar tombs alongside local peoples, perhaps suggestive of some form of fictive kinship, a potential by-product of growing interregional commerce. By relaxing the restraints of tomb membership, a more flexible and complex funerary ideology was adopted and reflects the broader appropriation of kinship in the formation of a multi-ethnic society. In addition, stable carbon isotope ratios suggest the consumption of a broad, mixed C3-C4 diet fitting with the employment of a variety of subsistence strategies, although preference was given to C3-based sources of food.;The dramatic changes in the archaeological record associated with the transition to the Wadi Suq period are not mirrored in isotopic indicators of paleomobility. As in the Umm an-Nar, the Wadi Suq population does not appear to have been highly mobile despite a decrease in the number, size, and permanence of settlements. Oxygen isotope values do not differ from the preceding period, and while strontium ratios are significantly different, this is likely a reflection of the exploitation of different geographic areas with correspondingly disparate isotope signatures. Stable carbon isotope values indicate a considerable change in subsistence practices involving a greater reliance on C3-based foodstuffs and a more restricted dietary intake, with an emphasis not on marine resources but on oasis agriculture. These data corroborate the strontium and oxygen isotope results and portray a society that was still relatively sedentary and continued to practice cultivation. Moreover, the continued presence of non-local immigrants interred in local tombs suggests that interregional economic relations did not completely break down during this "Dark Age" of purported cultural isolation.;The findings of this study illustrate continuity between the Umm an-Nar and Wadi Suq periods and call into question how substantial the so-called "collapse" of the early second millennium BC actually was. Furthermore, the presence of non-locals in both Umm an-Nar and Wadi Suq tombs, with no outward expression of foreign identity, reinforces the idea that these immigrants may have readily adopted the practices of their local host community, even in death. It appears that, rather than being subjugated by a hegemonic system controlled by more complex centers like the Indus Valley or Mesopotamia, the inhabitants of southeastern Arabia lived in relative autonomy. Finally, while local communities were undoubtedly affected by a disintegration of external economic relationships with the larger Gulf, this collapse may have also been partially influenced by internal social dynamics; however, isotopic evidence challenges the validity of an ideological conflict between traditional, kinship-based factions and a growing social elite.