The signal and the noise: inherent challenges for isotopic studies in bioarchaeology

Abstract

Isotopic analysis as a method of assessing diet or geographical origin is now ubiquitous in archaeology, to the point where seemingly no project is complete without it. Yet despite its prevalence, it is not a straightforward technique that provides a simple answer. I argue that many researchers overlook the fact that the situation is rarely clear-cut, with many contributing factors, that each situation is usually complex and can vary depending on the nature of each study or sample. This can lead to interpretations that are overly simple or at a higher degree of precision than are warranted by the data.

In this paper I outline some of the issues that confront us as we try to unravel the tangled web that is isotopic patterning in consumer data, in particular the factors that determine the limits of the technique’s resolution, and therefore our interpretations. I identify some points for best practice, and then discuss in more detail areas that I think need overt attention at the level of each and every study: confidence in specimen and data integrity; considerations of analytical scope and scale; data interrogation.