A comparison of subadult skeletal and dental development based on living and deceased samples

Abstract

Objectives A fundamental assumption in biological anthropology is that living individuals will present with different growth than non‐survivors of the same population. The aim is to address the question of whether growth and development data of non‐survivors are reflective of the biological consequences of selective mortality and/or stress. Materials and Methods The study compares dental development and skeletal growth collected from radiographic images of contemporary samples of living and deceased individuals from the United States (birth to 20 years) and South Africa (birth to 12 years). Further evaluation of deceased individuals is used to explore differential patterns among manners of death (MOD). Results Results do not show any significant differences in skeletal growth or dental development between living and deceased individuals. However, in the South African deceased sample the youngest individuals exhibited substantially smaller diaphyseal lengths than the living sample, but by 2 years of age the differences were negligible. In the US sample, neither significant nor substantial differences were found in dental development or diaphyseal length according to MOD and age (>2 years of age), though some long bones in individuals <2 years of age did show significant differences. No significant differences were noted in diaphyseal length according to MOD and age in the SA sample. Discussion The current findings refute the idea that contemporary deceased and living individuals would present with differential growth and development patterns through all of ontogeny as well as the assumptions linking short stature, poor environments, and MOD.

The Subadult Virtual Anthropology Database (SVAD): An Accessible Repository of Contemporary Subadult Reference Data

“…The differing contexts of origin for the SVAD samples and the fact that it is comprised of data from deceased and living individuals do not seem to influence the range of values for indicators in each population. A recent study showed no differences in long bone lengths and dental development between the deceased (medical examiner's office context) and living (hospital/clinical context) individuals from the U.S. and South African samples [10]. Although these findings should be verified on the other SVAD samples, they suggest there is no bias in skeletal and dental indicators that is related to the type of collaborating institution, the context of origin of the individuals (forensic or clinical), or the type of medical image (CT scan or radiograph), and that these indicators could be compared across samples for anthropological research [28].…”

“…These include one or several of the following limitations: relatively small samples [3,4], uneven age distributions [1], anatomically incomplete or taphonomically damaged skeletons, historic samples that do not accurately reflect contemporary growth and development or health [5,6], samples truncated to one type of indicator [7], and/or incomplete or inaccurate information on demographics, population affinity, or socio-economic status [1,6,8,9]. Therefore, the subadult material to use as reference material in forensic anthropology or for ontogenetic studies of modern populations is limited, if not questionable [10]. As evident with the Granada Collection [1] where infants younger than the age of one year old make up 80% of the subadult sample, available skeletal collections also often have unequal age distributions because of differential mortality risks in subadults.…”

“…As evident with the Granada Collection [1] where infants younger than the age of one year old make up 80% of the subadult sample, available skeletal collections also often have unequal age distributions because of differential mortality risks in subadults. Very young individuals, such as infants and perinates, are often over-represented compared to children and juveniles; mortality increases again with age and therefore adolescents are also usually over-represented compared to children and juveniles [10][11][12]. Unbalanced age groups can potentially bias results built with these samples, such as the negative impacts of age mimicry in regression models [13,14].…”

A growth area

“…Children in the Maresh study were noted to be larger and heavier than children from other North American growth studies [ 99 ]. Other datasets of long bone measurements are available that do encompass different socioeconomic and geographic contexts [ 106 ], and have been used in anthropological studies [ 107 ]. However, they do not necessarily encompass the full ontogenetic range, include all long bones, or incorporate as much detail regarding lifestyles.…”

“…These studies are informative but building on them using tools such as DXA to investigate skeletal linear dimensions and proportions would allow for deep time comparisons of growth variability. Researchers are working to include a greater range of childhood experiences in modern skeletal studies [ 74 , 107 ]; however, there is room to grow in this research area.…”