A life history approach to stature and body proportions in medieval Danes.

Abstract

Developmental plasticity, or the ability of physiological development to change in response to environmental pressures (external and internal), results in permanent physiological changes that can shape the later life health experiences of an individual. The timing of non-specific stress in relation to growth and development is critical to this interaction. Dental enamel provides detailed information on the timing of non-specific stress experiences, which may be considered in relation to growth in other physiological systems developing at the same time to elucidate the impact of one on the other. Examples of parallel developing systems include the immune, nervous, cardiovascular, respiratory, renal, and digestive systems (Chamley et al. 2005; MacGregor 2008; Bee & Boyd 2010). This research investigates these patterns through the consideration markers of enamel growth disruption known as accentuated striae of Retzius (AS) in relation to stature and body proportions in human skeletal remains. Anthropometrics and dental samples were collected from two medieval Danish cemetery samples. Residuals were calculated using linear regression from stature in the grave and all metrics were considered in relation to a total number of AS for each individual. A life course approach was also taken by considering AS at different stages of crown development in relation to each metric. Results indicate potential associations between AS and skeletal metrics (particularly tibial length and stature). These are most apparent in relation to AS rates in enamel developing from approximately 2 to 4.8 years of age. These results point to the utility of taking a life course approach in which enamel development is considered in relation to patterns of skeletal growth. Certain limitations and the need for further developments are highlighted by the nature of the results.