Documenting the Effects of Laboratory Sorting in Zooarchaeology: Lessons Learned from the Čḯx^wicən Project

Abstract Zooarchaeologists routinely analyze assemblages that were initially sorted into major animal type (birds, mammals, fish, invertebrates) by students or lab technicians with varied backgrounds in zooarchaeology. Sorting errors are probably made in this initial phase, which can affect taxonomic representation and understanding of human–animal relationships. Recent study of the immense faunal assemblage (over 1 million NSP [Number of Specimens]) from Čḯx w icən (45CA523), a 2,700-year-old Lower Elwha Klallam village located on the coast of Washington (USA), allows us to systematically analyze trends in sorting errors. For example, 22.6% of the bird bones included in our sample were initially missorted into other taxonomic groups, primarily mammal, but also fish and invertebrate. Fish bones were less frequently missorted, but certain taxa with unusual elements were affected. More than one-fourth (27.3%) of all mammal bone chips (debitage from tool production) were missorted. Failure to recognize and mitigate these errors could lead to significant biases. Lab managers need to recognize the potential for sorting error at the beginning and train lab technicians in the kinds of faunal remains they will be encountering, including distinctive elements. Collaborative researchers need to develop protocols for transferring specimens, and scholars working with “legacy collections” should not assume the collections were sorted correctly.