With National Science Foundation support Drs. Joan Brenner Coltrain and Shawn Carlyle will analyze the bone chemistry of a human burial collection from the American Southwest. The burials under study make up the "Basketmaker Collection" and are housed at the Peabody Museum of Archaeology and Ethnology at Harvard. Basketmaker people are thought to represent the earliest farmers in the Four Corners region, predating the Anasazi, lived in pit houses rather than adobe structures and used basketry rather than pottery. The Peabody Basketmaker collection was assembled early in the twentieth century and is not as well documented as later collections recovered using systematic excavation and recording methods. Firmly establishing the timeframe in which they lived, their reliance on maize as a dietary staple and their genetic ancestry will add measurably to our understanding of this important period in Southwest prehistory. We will use three techniques in this study. The first is radiocarbon dating. This is accomplished by isolating and purifying a protein called collagen from a small piece of bone. Collagen makes up the supporting framework of bone and is comprised of amino acids that contain carbon. A small fraction of this carbon is the radioactive isotope of carbon, 14C, allowing us to obtain a radiocarbon date from bone collagen. The second technique is a two-part analysis of Basketmaker diets. The first is based on two stable isotopes of carbon found in bone collagen, 13C and 12C. The ratio of 13C to 12C covaries with the amount of maize in the diet of sampled individuals and will be measured on the same isolated and purified proteins that are used in radiocarbon dating. The second assay will measure the ratio of two stable isotopes of nitrogen in bone collagen, 15N and 14N, to estimate how much animal protein our study population consumed. It is very possible that as Basketmaker people became more sedentary and began to rely more heavily on maize, they consumed less animal protein, perhaps as a consequence of reduced animal prey densities. Finally, we will extract mitochondrial DNA from small pieces of bone to determine the genetic relationship between Basketmaker people and the Mimbres who lived to the south, the Fremont who lived to the north, the Anasazi who followed the Basketmaker in time and modern American Indian groups. This will be accomplished by identifying specific maternal lineages evident in the mitochondrial genome and by sequencing DNA in specific regions of that genome. The data from these procedures will improve our understanding of who the Basketmaker people were, when they arrived in the Four Corners region and how reliant they were on maize agriculture over time. In addition and of equal importance, these data will allow the Peabody Museum to comply with federal legislation (NAGPRA) that requires them, and all American institutions curating Native American remains, to return or repatriate these remains to descendent tribal groups if requested. Currently, several tribes have requested the Basketmaker collection. To equitably repatriate this collection is contingent upon the genetic relationships and temporal framework under study.
