Titolo della tesi: The Ra’s al-Hamra 5 and Daba al Bayah graveyards (Sultanate of Oman): demographic, paleopathological, and mortuary practice assessments
This Ph.D. dissertation offers an in-depth bioarchaeological study of the skeletal remains of the Omani sites of Ra's al-Harma 5 (Neolithic period) and Daba al Bayah (Late Bronze Age-PIR). From the site of Ra’s al-Hamra 5 (RH5), skeletal remains from the Area 43 were assessed. Two separate tombs were studied from the funerary complex of Daba al Bayah, the Large Collective Grave 1 (LCG-1) and the Large Collective Grave 2 (LCG-2). The main osteological aims of this study were the reconstruction of the paleodemographic profile, the state of health and lifestyle of the ancient communities. Additional goal of the study was to assess the funeral practices adopted at the sites. Osteological, paleopathological and histological analyzes were used together with archaeological and taphonomic observations. The interdisciplinary approach made it possible to reconstruct aspects such as mortality and life expectancy, the state of health related to activities in life and diet, the action of fire and the diagenetic changes on human skeletal remains. The funerary contexts of both sites were also studied with the aim of re-examining the taphonomic terminologies used in archaeological contexts and, specifically, the terms relating to "collective burials".
- Area 43 of Ra’s al-Hamra 5
Area 43 of the RH5 graveyard was first excavated between 1981 and 1985, it immediately appeared different when compared to the rest of the RH5 graveyard. The RH5 graveyard was characterized by primary and secondary depositions. Area 43, on the other hand, appeared as a vast area of dispersion of partially burned, fragmented, and commingled human remains. Several hypotheses were considered to explain this difference, including catastrophic events (epidemics, conflicts between groups), the presence of different groups or differences within the same group, or movements of skeletal remains related to reorganization of spaces. The anthropological analyzes conducted on the skeletal remains allowed to determine the minimum number of individuals (MNI) within Area 43. The determined MNI is 77, specifically 2 fetuses, 29 sub-adults and 46 adults. Where possible, the sex of adult individuals was determined: 20 individuals are male or probably male, 19 individuals are female or probably female. The sex of seven individuals could not be determined.
Despite the state of conservation of the remains, various skeletal lesions were documented such as metabolic lesions, degenerative joint disease, arthrosis, infections, periostitis, antemortem tooth loss. The frequency of lesions was calculated on the number of skeletal elements analyzed and not by individuals. Oral pathologies were also calculated on the number of teeth and alveoli analyzed. In general, from a paleopathological point of view, no differences were found between adults and sub-adults regarding the frequency of skeletal lesions, with the only exception of periostitis which appears in significantly higher percentages in adults. This finding suggests greater survival from these lesions in adults than in sub-adults. In addition, more than 93% of sub-adult burials in Area 43 have no skeletal lesions. Hence, the health problems for the younger individuals of this community appear to be acute in origin.
The demographic and paleopathological comparison between the data relating to the remains from Area 43 and those from the burials of the rest of the graveyard did not show any differences that could explain the formation of this area as the result of a catastrophic event. The absence of clear differences between Area 43 and the rest of the RH5 graveyard both in demography and paleopathology allowed to combine the data to make comparisons with other contemporary populations. Data related to age assessment from all the individuals excavated within the RH5 graveyard were used to reconstruct life expectancy and mortality rates. Considering the underestimation of sub-adults between 0-4 years, the formulas proposed by Bocquet and Masset (1977) were used. A Juvenility Index (JI) of 0.2259 was calculated. Based on the JI the life expectancy at birth (e0 = 22.07 ± 1.503), the mortality rates in the first year of life (1q0 = 0.293 ± 0.016) and in the first 5 years of life (5q0 = 0.470 ± 0.041) were calculated.
The life expectancy value and mortality rates were compared with data from the Neolithic site of Jebel al-Buhais 18 (BHS18). In the BHS18 site too an underrepresentation of sub-adults between 0-4 years of age was highlighted. The application of the formulas proposed by Bocquet and Masset (1977) to the BHS18 site allow to reconstruct a 10-years difference in life expectancy at birth compared to the RH5 graveyard. This difference reflects the difference in percentages of death among the two communities. In Jebel al-Buhais 18 the frequency of adult death between 20 and 34 years of age is higher than RH5. On the contrary, in the RH5 graveyard the number of sub-adults’ death between 5 and 14 years of age is higher compared to BHS18. This data might only reflect numerical variations or can be related to an increase in mortality among sub-adults due to the high frequency of spina bifida found in the RH5 site.
Paleopathological data from the RH5 site were also compared with those from other Neolithic sites, distinguishing the different subsistence economies (fisherman-gatherer communities, pastoral communities, agricultural communities). Comparison of oral defects between the RH5 skeletal remains and those of other Omani Neolithic fisherman-gatherer communities highlights similar patterns. None of the teeth on the sites have caries, reflecting a low-sugar and low-carbohydrate diet. The comparison with paleopathological data from the pastoral site of Jebel al-Buhais 18 does not show any differences in oral pathologies. This reflects types of low-sugar diets. Compared to RH5, however, the Jebel al-Buhais 18 site shows significantly higher rates of degenerative pathologies of the spine and joints of the ankle and elbow. This difference between the two communities could be associated with physical stress associated with herding activities and traveling on uneven land to which the individuals from Jebel al-Buhais 18 were subjected. The comparison of paleopathological data from RH5 with those from different Neolithic agricultural communities highlights significantly higher rates of skeletal lesions in agricultural communities. Dental and skeletal lesion frequencies suggest that fishing and gathering as a lifestyle caused individuals of RH5 lower frequencies of chronic conditions than those observed among Neolithic farmers.
The interdisciplinary analysis conducted on the human remains from Area 43 allowed also to reconstruct various funeral practices used by this community. Histological analyzes conducted on rib samples from Area 43 highlighted different percentages of bioerosion in both burned and unburned samples. Considering that the action of fire reduces and interrupts the action of microorganisms that feed on the organic component of the bone, the presence of high percentages of bioerosion even in burnt samples allowed to hypothesize periods of exposure of variable duration before the burning of some of the remains from Area 43. This data confirms what is documented by the observation of the surface of the skeletal remains. Of the total skeletal remains analyzed (917), 20.5% show signs of surface alteration related to the exposure of fresh bones in the open air. Based on anthropological and histological data, it was therefore possible to reconstruct a variety of funerary practices. Some remains were exposed to the open air before deposition although the absence of marks related to animal activity (rodents and carnivores) suggests that the exposition happened in places protected from animal attacks. Other remains were immediately buried. Furthermore, some individuals were burned before deposition. The almost total absence of traces of manipulation allows to exclude that the remains in secondary deposition were previously de-fleshed. Additionally, the study of the archaeological data combined with the analysis of the remains with known location within the excavation area allowed to identify specific sectors of Area 43 in which burnt human remains were found.
In general, anthropological and archaeological data allowed to reconstruct that the formation of Area 43 is not the result of a single event but of a series of actions and practices that happened in the area and contributed to the fragmented and highly commingled state of the human remains.
- The Daba al Bayah funerary complex
The second site analyzed was the funerary complex of Daba al Bayah. The complex, still under excavation, currently consists of two large rectangular tombs containing the remains of multiple individuals. The two tombs are dated differently, based on grave goods found. The LCG-1 tomb is dated between the Late Bronze Age and the Early Iron Age. The LCG-2 tomb was used for a longer period from the beginning of the Iron Age to the Pre-Islamic period. The pandemic situation connected to Covid19 allowed to conduct only a preliminary analysis of the human skeletal remains from the burial site.
From the LCG-1 tomb, mandibles and maxillary bones were analyzed. The analysis allowed to determine a minimum number of adult individuals of 79 and a minimum number of sub-adult individuals of 15. The skeletal elements were analyzed for oral pathologies (periapical lesions and antemortem tooth loss). Frequencies were determined based on the number of alveoli available for the study. The comparison between maxillary and mandibular alveoli revealed higher percentages of antemortem tooth loss on almost all lower sockets. Additionally, several permanent teeth (81) were analyzed for dental caries. Twelve teeth exhibit at least one caries each. The paleopathological data collected were compared with those from other Bronze Age sites. The comparison documented similar frequencies of oral defects between Daba LCG-1 and the sites of Bahrain and Shimal, reflecting a diet rich in sugars and carbohydrates, typical of the agricultural subsistence of the Arabian Gulf. Sub-adult skeletal elements and deciduous teeth were also analyzed. Of the deciduous teeth, 5 show caries. Antemortem tooth loss are found on the maxillary bones and mandibles of two sub-adult individuals (15-18 years). These data suggest a high-sugar diet, which involved tooth decay and tooth loss at a young age.
From the LCG-2 tomb of Daba the human remains from primary depositions excavated (73 individuals) were analyzed. Dividing the individuals by general age groupings, 4 individuals are fetal/perinatal individuals, 26 are infants (0-3 years of age), 5 are children (4-8 years), 2 are juvenile (9-12 years), 2 are adolescents (13-19 years) and the remaining 34 individuals are adults. Of the adults, 12 are male or probably male and 19 are female or probably female. It was not possible to determine the sex of 3 adult individuals. Given the continuity of use of the tomb, the remains were then chronologically divided into the three periods of use (Early Iron Age, Late Iron Age and PIR period). The paucity of the sample datable to the PIR period meant that the study focused on the remains of the Iron Age period, although a demographic and paleopathological study was also performed on the PIR burials. The comparison of demographic data between Early Iron Age and Late Iron Age shows higher percentages of infants (0-3 years) compared to the other sub-adult age groups. Based on the ages determined for the Iron Age burials a life table was created. A life expectancy value of about 20 years was calculated. Compared to the Neolithic sites of Ra’s al-Hamra 5 and Jebel al-Buhais 18, it appears that the 0-4 age group is not underrepresented. Taphonomic data, burial practices, and the sedentary lifestyle compared to the seasonality of the Neolithic site were considered as explanation for the high number of 0-4 individuals recovered in the Daba LCG-2 tomb.
The analysis of skeletal lesions from the Iron Age burials revealed a general lack of indicators of chronic stressors in sub-adults compared to adult individuals. The difference is high in both periods (Early Iron Age and Late Iron Age). These data allow to hypothesize acute pathologies that participate in the high mortality rate among sub-adults. Statistically higher differences between adults and sub-adults are found for infections and periostitic lesions. Adults have higher percentages compared to sub-adults. The adult skeletal remains from both periods (Early Iron Age and Late Iron Age) show skeletal lesions (OA and DJD) that reflect age and daily work efforts. No statistically relevant differences are found comparing skeletal lesions by sex. The analysis of oral defects (antemortem tooth loss, periapical lytic lesions, and caries) shows higher frequencies of antemortem tooth loss in mandibular sockets compared to maxillary sockets. The analysis of oral lesions by sex shows significant differences for antemortem tooth loss. Females from EIA period showed higher frequencies of oral defects than males. The difference might be the result of a different diet characterized by more cariogenic foods or might reflect a different use of teeth related to life activities.
Paleopathological data related to oral pathologies were then compared with data from other Iron Age sites. In general, data reported for oral and dental pathologies from the Daba LCG-2 burials allowed to reconstruct a subsistence economy for this community based on the consumption of foods high in fermentable carbohydrates since young age. This data is in line with what reported by Littleton and Frohlich (1993) and by Nelson and colleagues (1999) for several sites of the Arabian Gulf and in the Arabian Peninsula.
The archaeological data from the two tombs were studied with the aim of reconstructing funerary actions and practices used by these communities. Data related to archeological and anthropological field excavation and data from previous studies of human skeletal remains were considered. Based on the anthropological data recovered by the anthropologists A. Todero and L. Fattore and based on the number count determined using maxillary and mandibles, a bias in number count was highlighted. High difference between the MNI count and the skeletal element count (hand/foot small bones, maxillary, and mandibles) is found. The limited data related to LCG-1 field excavation makes it difficult to accurately reconstruct the funerary practices and to clearly explain this bias.
As far as the Daba LCG-2 tomb concern, the continuity of use of the tomb is documented both by the archaeological materials found and by the funerary practices recognized by the anthropologists during field excavations. Different actions occurred at different times. These actions appear in the form of accumulations of bones and archaeological materials (Bone Clusters), burial depositions of individuals and creation of new spaces within the structure (Chambers).
- The terminological problem of “collective burials”
Different and non-standardized terms are used in literature to describe the burial depositions of several individuals. Some terms focus more on the archaeological aspects of the deposition and this makes it difficult to search for comparison unless you are dealing with the same culture. Different terms are also used in the anthropological field. Some are simply descriptive while others involve an interpretation of funeral actions and ideologies. The most debated term is the one concerning the so-called “collective burials”. This definition is generally used in Archeothanatology and describes the burial depositions, staggered over time, of several individuals within a single structure. The analysis of the two Omani sites of Ra’s al-Hamra 5 and Daba al Bayah has demonstrated that in the study of a funerary deposit several data need to be considered. Archaeological, anthropological, taphonomic, historic and sociocultural data need to be evaluated together to reconstruct all the information that a funerary context can provide. In this perspective, the term "collective" used in Archeothanatology must be considered as one of the pieces of a more extensive and complex analysis that can provide important information about the society and its organization and funerary behavior.