Taking shape: A new geometric morphometric approach to quantifying dental fluctuating asymmetry and its application to the evaluation of developmental stress

Abstract

Although evaluating developmental stress is challenging, it is critical to understanding phenotypic adaptation and differentials in morbidity and mortality related to spatiotemporal variation in environmental and cultural factors. This paper presents a new, reproducible, and reliable geometric morphometric (GM) protocol through which stress-induced deviations to symmetry, known as fluctuating asymmetry (FA), can be robustly quantified. A case study, in which maternally mediated early-life stress in human skeletal remains is explored through first permanent molar (M1) FA, illustrates the method's effectiveness and wide-ranging potential to revolutionise the investigation of themes such as stress intensity, developmental processes, and buffering mechanisms in past populations.