INTRODUCTIONINTRODUCTION This study sought to determine a subadult age distribution based on left proximal femora from the Early Bronze Age site of Bab edh-Dhra', Jordan. The site had a permanent settlement from the Early Bronze Age IB (EBIB: beginning in 3050 BCE), through 2000 BCE in the Early Bronze Age IV (EBIV). A large cemetery near this settlement has burials from Early Bronze Age IA (EBIA: 3150-2950 BC) through EBIV (2300-2010 BC). Notably, there were several shifts in mortuary practices, starting with multiple chamber shaft tombs in the EBIA, changing to above-ground charnel houses in the Early Bronze Age II-III (EBII-III; 2800-2300 BC), and returning to subterranean tombs in EBIV (Schaub and Rast 1989).

METHODSMETHODSThe sample was composed of subadult femora from numerous EBIA shaft tombs, as well as from Charnel House A22, a rectangular mudbrick structure dating to EBII-III, housing at least 219 individuals whose remains were commingled and burnt in antiquity. There are at least 102 subadults (based on the femora in this study), but because the remains are commingled it is impossible to assign individual ages using dental development or skeletal maturation.

RESULTSRESULTS The 95% range of femoral lengths were compiled for each sample and age category (Figures 1-3). Different femoral length ranges, based on the highest, lowest, intermediate, and Bab edh-Dhra' EBIA means for each age category, gave age distributions for EBII-III femora as in Figure 4. The age categorizations for the EBII- III femora based on the Bab edh-Dhra' EBIA mean length data gave the best age estimates when compared to those derived from the Bab edh-Dhra' EBII-III mandible dental data (Figure 5, 2=2.14 p=0.54, df =3), though the age categorizations based on the intermediate means gave estimates that were not significantly different from those of the dental data (2=6.32, p=0.097, df=3) as did the categorizations based on the highest means (2=3.47, p=0.18, df=2). These were, however, significantly different from the categorizations based on Bab edh-Dhra' EBIA length means (2=10.49, p=0.015, df=3 for intermediate estimates, 2=15.67, p=0.0013, df=3 for highest mean estimates). Of the comparative data, there were only significant differences between the Bab edh-Dhra' EBII-III age distributions determined from Bab edh-Dhra' EBIA means and age distributions of the Arikara (2=51.06, p<0.001, df=3), the Belleville cemetery (2=30.28, p<0.001, df=2), & the K2 site (p=0.028, Fisher's exact test). When the EBII-III age distribution, based on the EBIA means, was compared to the subadult age distribution of the Bab edh-Dhra' EBIA femora determined using the same methods, there was a statistically significant difference from Bab edh-Dhra' EBII-III (Figure 6, 2=6.65, p=0.036, df=2).

DISCUSSION & CONCLUSIONSDISCUSSION & CONCLUSIONSOur results indicate that the femora represent 10.7% fetal or infant bones, 30.4% young children, 37.5% older children, and 21.4% adolescents in the Bab edh-Dhra' EBII-III A22 charnel house. These results are consistent with those obtained from dental data (DiMucci and McClellan, 2009. There was a significant difference between the Bab edh-Dhra' EBIA and EBII-III periods when using only femoral aging, but in this case it may be that the Bab edh-Dhra' EBII-III proportion of older children was over-

estimated because of the small range of femoral length estimates for this category due to smaller sample size  (Figure 3). However, the femoral results are very different from those reported by Ortner and Frohlich (2008) for the Bab edh-Dhra' EBIA cemetery taking into account all skeletal elements, where the majority of remains were fetal or infant remains. Since the EBIA femoral data provided estimates more similar to those of EBII-III A22, it may be that the determined age distribution for EBII-III is due to a problem with sampling and is not a real age distribution for those who died or were buried. Taphonomic processes may have played a major role in creating the assemblage. This may be especially important in A22, which are fire-burned, broken and commingled.  

Alternatively, it may be that cultural practices led to differential burial practices between time periods (Ortner and Frohlich, 2008), wherein fewer neonates and infants were buried with older children and adults in EBII-III. Finally, there may have been a real difference in mortality between the Bab edh-Dhra' EBIA and EBIII periods, following the shift in settlement and subsistence patterns. This project illustrated that age distributions can be estimated from fragmentary remains, particularly when considered in conjunction with multiple age indicators .

ACKNOWLEDGEMENTSACKNOWLEDGEMENTSThis research was supported by the NSF-REU (SES 0649088) Summer Research in Biological Anthropology program at the University of Notre Dame. We would like to thank: Elizabeth Studer for her work during the first part of this study; Hiba Ahmed, Mary DeAgostino, and Lesley Gregoricka for their time and patient advice; Dr. Brenda Baker for her invaluable expertise in counseling the direction of our project; Dr. Donald Ortner for allowing us to work with the Bab edh-Dhra' EBIA collection under his care; Dr. Robert Hoppa for his timely replies and assistance in developing our methods; and Dr. Janusz Piontek for his kind support and interest in our research, as well as for sending us invaluable data.

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Table 1. Comparative collections (# refers to the x-axis of each graph below)

Figure 1. Femur lengths, infants

Figure 2. Femur lengths, young children

Figure 3. Femur length, old children

Figure 5. Age distribution com-parison of femoral vs. dental data

Figure 6. Age distributions for the Bab edh-Dhra’ EB IA vs IIB femora

Figure 4. Age distribution based on mean femoral length/age category

Fetal Infant Young Child Old Child Adolescent

Fetal/Infant Young Child Old Child Adolescent

Fetal Infant Young Child Old Child

A copy of this poster is available for download at:http://www.nd.edu/~nsfbones/nsfbones/Posters_Presentations.html

Subadult age estimates of an Early Bronze Subadult age estimates of an Early Bronze Age charnel house at Bab edh-Dhra’, JordanAge charnel house at Bab edh-Dhra’, Jordan

Catalina I VillamilCatalina I Villamil11; JM Ullinger, MA; JM Ullinger, MA22; SG Sheridan, PhD; SG Sheridan, PhD33

1Dept. of Anthropology, Univ. of Pennsylvania; 2Dept. of Anthropology, The Ohio State University; 3Dept. of Anthropology, Univ. of Notre Dame