How Many People? Determining the Number of Individuals Represented by Commingled Human Remains

Much of the literature that deals with various quantification techniques comes from faunal analysis. Generally, these techniques have two goals when working with animal remains. The first is to quantify the deposited/recovered faunal assemblage and from this data extrapolate information about past hominid behavior. The results of such studies attempt to draw conclusions concerning human diet, animal procurement strategies, and predator-prey relationships (Lyman 1987). The second goal is directed toward quantifying the recovered faunal assemblage in order to reconstruct the living community of animals. The results of these types of studies attempt to drawconclusions concerning faunal turnover and succession, reconstruction of paleoenvironmental conditions, and geographic faunal patterns (Lyman 1987). When working with commingled human remains, the goal of quantification is obviously to estimate the total number of dead, and many of the techniques developed for faunal analysis are not appropriate. Two exceptions are the Minimum Number of Individuals (MNI) and the Lincoln Index (LI). In paleodemographic studies, estimation of the number of individuals is critical for the interpretation of past cultures, while in the forensic context it is vital for the identification process and for possible criminal trials. With few exceptions, the extent of discussions concerning commingled human remains revolves almost exclusively around the MNI. Certainly, one of the reasons for the popularity of the MNI is due to the ease of its calculation. Another reason is that most physical anthropologists are not familiar with other options. Recent research has shown that the Lincoln Index (LI) is a viable option for dealing with human remains and is not significantly more complicated than the MNI in its calculation (Adams 1996). A more statistically accurate modification of the LI has been presented called the Most Likely Number of Individuals, or MLNI (Adams and Konigsberg 2004). These alternatives to the MNI provide physical anthropologists with more analytical power when dealing with commingled remains. The key difference between the MNI and the LI or MLNI is that both the LI and MLNI estimate the original number of individuals represented by the osteological assemblage, while the MNI only estimates the recovered assemblage. In cases of taphonomic loss, this distinction can be quite important since the values presented by the MNI may provide misleading number estimates. The LI and MLNI, on the other hand, will present a more accurate estimate of the original population size that can be used for paleodemographic or forensic purposes. Furthermore, it is possible to provide confidence intervals with the LI and MLNI, but not with the MNI.