Department of Sociology and Anththropology

Stable oxygen isotopic studies of migration and mobility using human tissue are based on the premise that δ 18 O values of potable water sources are relatively stable over time and vary predictably across the landscape. Local variability of δ 18 O is generally assumed to be negligible and negated by an averaging effect as oxygen is consumed primarily as imbibed liquid and incorporated into tissue. This study tests the assumption that variability of δ 18 O ratios of water from within a region are insufficient to impact the reconstruction of ancient mobility using isotopic measures of human tooth and bone. This case study focuses on the Maya area of Guatemala and Mexico, a region where many analyses of oxygen isotopic ratios in ancient human tissue has been conducted. 71 water samples were obtained over the course of five years, from precipitation, streams, rivers, lakes, aguadas (watering holes), civals (perennial wetlands), and caves. Unlike most baseline studies, the objective here was the repeated testing of a diversity of sources from the same location. δ 18 O VSMOW values from surface and meteoric water range from −16.0 to +3.6‰. The precipitation range is −16.0 to 1.58‰ (n = 22) with the highest and lowest values measured at the same location (El Zotz, Guatemala). The surface water range is − 9.2 to 3.6 (n = 48), the lowest value is the Usumacinta River at Yaxchilan and the highest value is from a lake located 65 kilometers away. The δ 18 O values of local streams were remarkably stable over time. Major rivers, such as the Usumacinta River, have relatively constant values. Closed water basins (lakes, aguadas, and civals) demonstrated an evaporative effect and δ 18 O was variable both between basins and in individual basins over time. In the Petén region, mean δ 18 O of precipitation is statistically different than that of lake and aguada water. Local δ 18 O differences in consumed water likely explain the variability observed in human tooth enamel at Tikal and other Petén region sites. This case study demonstrates that local isotopic values may be more diverse than is generally assumed in studies of human mobility that rely on little to no baseline data. Future studies of mobility based on oxygen isotopic measures of ancient human tooth and bone should include measures of both meteoric water and a diverse range of surface and groundwater to develop more robust interpretations of oxygen isotopic values in ancient human tissue.

In 1876, Charles Warren described his method of tunneling excavations in Jerusalem as follows: "We mined in this case down to the rock, and then run along its surface until we reached the great wall, and there we commenced our work, examining the masonry" (Warren 1876:149). Warren headed underground because he had angered a local sheik in his search for Herod's Temple, which lay beneath the Haram ai-Sharif. While the ethics of this somewhat secretive approach have been rightfully questioned, the tunneling methodology stands as a meaningful contribution to archaeological ABSTRACT Archaeological tunneling is a standard excavation strategy in Mesoamerica. The ancient Maya built new structures atop older ones that were no longer deemed usable, whether for logistical or ideological reasons. This means that as archaeologists excavate horizontal tunnels into ancient Maya structures, they are essentially moving back in time. As earlier constructions are encountered, these tunnels may deviate in many directions in order to document architectural remains. The resultant excavations often become intricate labyrinths, extending dozens of meters. Traditional forms of archaeological documentation, such as photographs, plan views, and profile drawings, are limited in their ability to convey the complexity of tunnel excavations. Terrestrial Lidar (light detection and ranging) instruments are able to generate precise 3D models of tunnel excavations. This article presents the results of a model created with a Faro™ Focus 3D 120 Scanner of tunneling excavations at the site of EI Zotz, Guatemala. The lidar data document the excavations inside a large mortuary pyramid, including intricately decorated architecture from an Early Classic (A.D. 300-600) platform buried within the present form of the structure. Increased collaboration between archaeologists and scholars with technical expertise maximizes the effectiveness of 3D models, as does presenting digital results in tandem with traditional forms of documentation.

Excavations within the S-Sector at Piedras Negras in 2016 yielded an assemblage of lithic and bone artifacts consistent with evidence of craft production. The Proyecto Paisaje Piedras Negras – Yaxchilan returned to the S-Sector during the 2017 field season to conduct more extensive excavations in an attempt to understand production and exchange at this Maya polity capital. Between the 2016 and 2017 seasons, over 4,300 fragments of worked and unworked bone, both human and animal, were excavated from the S-Sector. Here we present the preliminary results of an integrated bioarchaeological and zooarchaeological analysis of the materials. The significance of this assemblage lies in its composition, consisting of both human and animal bone, including finished tools, ornaments, and production debris. Especially notable are large quantities of bone objects used in the working of textiles. Among the human remains are a sizable quantity of isolated, pathological teeth that we believe may be the remains of tooth extractions.