An anthropologist has been researching how Native Americans in California were impacted by Spanish missionization from 1776 to 1830. The researcher is particularly interested in how Native Californians may have negotiated their identity and balanced traditional practices with colonial influences. Therefore, the anthropologist excavates material remains from areas where the Native Californians may have gone when they fled the Spanish missions. The materials include things such as stone tools, shell beads, and historic bottle glass. These materials are analyzed and used in conjunction with historical documents to help the researcher better understand what life was like for Native Californians at that time. What is the primary field of anthropology addressed in this research?