Tracy L. Prowse

Isotopic and dental evidence for infant and young child feeding practices in an imperial Roman skeletal sample

This study integrates isotopic, palaeopathological, and historical evidence to investigate infant and young child feeding practices in a Roman period (1st to 3rd centuries AD) skeletal sample from the Isola Sacra necropolis (Rome, Italy). Stable isotope analysis of bone collagen from 37 rib samples indicates that transitional feeding began by the end of the first year and weaning occurred by 2-2.5 years of age. Both delta(15)N and delta(13)C data clearly show the trophic level effect associated with breastfeeding. Childhood diet is investigated using dental pathology data in the deciduous dentitions of 78 individuals aged between 1 and 12 years. The presence of calculus, caries, and tooth wear in young children suggests that individuals were provided complementary foods and other items that impacted their dental health at an early age. The isotopic and dental data are generally consistent with the historical evidence from the Roman period with respect to the general timetable of weaning and the character of complementary foods. This is the first study to integrate isotopic and deciduous dental pathology data to explore infant and young child feeding practices in the Roman world.

Concordance of cranial and dental morphological traits and evidence for endogamy in ancient Egypt

A biological affinities study based on frequencies of cranial nonmetric traits in skeletal samples from three cemeteries at predynastic Naqada, Egypt, confirms the results of a recent nonmetric dental morphological analysis. Both cranial and dental traits analyses indicate that the individuals buried in a cemetery characterized archaeologically as high status are significantly different from individuals buried in two other, apparently nonelite cemeteries and that the nonelite samples are not significantly different from each other. A comparison with neighbouring Nile Valley skeletal samples suggests that the high status cemetery represents an endogamous ruling or elite segment of the local population at Naqada, which is more closely related to populations in northern Nubia than to neighbouring populations in southern Egypt.

You are not what you eat during physiological stress: Isotopic evaluation of human hair

Variation in δ(13) C and δ(15) N values can be assessed to understand not only diet, but also the influence of physiological factors on an individual. The metabolic balance of an individual can impact isotopic signals in tissues that are forming during the periods of metabolic stress. Fluctuating δ(15) N values are associated with physiological stressors that alter an individuals metabolism such as infection, injury, or pregnancy. This study examines variation in δ(13) C and δ(15) N values along sequentially segmented hair in both modern and archaeological individuals. Subjects with an observable skeletal pathology, known chronic illness, or evidence of pregnancy were compared with controls exhibiting no evidence of physiological stress. The results on hair samples from individuals from 19(th) century Belleville, Ontario, four modern cadavers (two with cancer and two sudden deaths), and two living pregnant women indicate that δ(15) N values are approximately 1‰ higher in individuals with a pathological condition (e.g., infection, fracture, or cancer) and are 1‰ lower during pregnancy, whereas δ(13) C values show less variability. Higher nitrogen values may represent the recycling of nitrogen derived from the breakdown of existing proteins in the body (catabolism), whereas lower δ(15) N values are related to increased utilization of dietary and urea nitrogen for tissue synthesis during pregnancy. These findings suggest that short-term fluctuations of δ(15) N values may be the result of changes in an individuals metabolic balance, and that metabolic imbalance poses a confounding factor to ancient dietary studies when using rapidly growing tissues such as hair.

Plasmodium falciparum malaria in 1st–2nd century CE southern Italy

The historical record attests to the devastation malaria exacted on ancient civilizations, particularly the Roman Empire [1]. However, evidence for the presence of malaria during the Imperial period in Italy (1st-5th century CE) is based on indirect sources, such as historical, epigraphic, or skeletal evidence. Although these sources are crucial for revealing the context of this disease, they cannot establish the causative species of Plasmodium. Importantly, definitive evidence for the presence of malaria is now possible through the implementation of ancient DNA technology. As malaria is presumed to have been at its zenith during the Imperial period [1], we selected first or second molars from 58 adults from three cemeteries from this time: Isola Sacra (associated with Portus Romae, 1st-3rd century CE), Velia (1st-2nd century CE), and Vagnari (1st-4th century CE). We performed hybridization capture using baits designed from the mitochondrial (mtDNA) genomes of Plasmodium spp. on a prioritized subset of 11 adults (informed by metagenomic sequencing). The mtDNA sequences generated provided compelling phylogenetic evidence for the presence of P. falciparum in two individuals. This is the first genomic data directly implicating P. falciparum in Imperial period southern Italy in adults.

Exploring Dietary Variability in a War of 1812 Skeletal Collection from Stoney Creek, Ontario, Using Stable Carbon and Nitrogen Isotopes

The stable isotope composition of human bones was analyzed to investigate the diet of 19th-century soldiers who died during the Battle of Stoney Creek, Ontario, on 6 June 1813. Eighteen bones were selected from the skeletal remains recovered from the Smith’s Knoll Monument to identify the diets of these soldiers in the years prior to their deaths on the battlefield. The carbon and nitrogen isotopic data suggest a high degree of dietary variability within the Smith’s Knoll sample. The δ13C and δ15N values obtained from bone collagen and δ13C values from bone carbonate indicate that, throughout both their civilian and military lives, the Smith’s Knoll soldiers consumed carbohydrates (e.g., wheat and maize) with protein derived primarily from terrestrial sources in the form of domestic livestock. Our results suggest that most of these individuals consumed staple foods characteristic of diets in 19th-century North America and the United Kingdom, with a small number of individuals (n=2) supplementing its diet with freshwater fish.

Mapping the origins of Imperial Roman workers (1st-4th century CE) at Vagnari, Southern Italy, using 87Sr/86Sr and δ18O variability

OBJECTIVES We obtained the oxygen and strontium isotope composition of teeth from Roman period (1st to 4th century CE) inhabitants buried in the Vagnari cemetery (Southern Italy), and present the first strontium isotope variation map of the Italian peninsula using previously published data sets and new strontium data. We test the hypothesis that the Vagnari population was predominantly composed of local individuals, instead of migrants originating from abroad. MATERIALS AND METHODS We analyzed the oxygen (18 O/16 O) and strontium (87 Sr/86 Sr) isotope composition of 43 teeth. We also report the 87 Sr/86 Sr composition of an additional 13 molars, 87 Sr/86 Sr values from fauna (n = 10), and soil (n = 5) samples local to the area around Vagnari. The 87 Sr/86 Sr variation map of Italy uses 87 Sr/86 Sr values obtained from previously published data sources from across Italy (n = 199). RESULTS Converted tooth carbonate (δ18 ODW ) and 87 Sr/86 Sr data indicate that the majority of individuals buried at Vagnari were local to the region. ArcGIS bounded Inverse Distance Weighting (IDW) interpolation of the pan-Italian 87 Sr/86 Sr data set approximates the expected 87 Sr/86 Sr range of Italys geological substratum, producing the first strontium map of the Italian peninsula. DISCUSSION Results suggest that only 7% of individuals buried at Vagnari were born elsewhere and migrated to Vagnari, while the remaining individuals were either local to Vagnari (58%), or from the southern Italian peninsula (34%). Our results are consistent with the suggestion that Roman Imperial lower-class populations in southern Italy sustained their numbers through local reproduction measures, and not through large-scale immigration from outside the Italian peninsula.

Age estimation in older adults: Use of pulp/tooth ratios calculated from tooth sections

OBJECTIVES Accurate age estimates are foundational for bioarchaeological research, yet the ability to accurately age older adult skeletons remains elusive. This study uses a new version of pulp/tooth area calculations to investigate chronological age of older archaeological individuals. MATERIALS AND METHODS Pulp/tooth area ratios were calculated on modern control teeth (n = 10) that were first radiographed and then sectioned for comparative analysis. Pulp/tooth area ratios were determined on sectioned teeth using ImageJ software for: (a) modern individuals of known age (n = 26); (b) individuals from Belleville, Ontario, Canada (1821-1874) with documented age (n = 50); and (c) Belleville individuals with skeletally estimated age (n = 122). RESULTS Calculations from tooth sections on modern teeth (n = 10) resulted in a mean absolute error (MAE) of ±3.9 years, whereas the radiographic method for the same teeth had an MAE of ±14.45 years. Results indicate that sectioned pulp/tooth area ratios are a significant predictor of chronological age (p < .005), with MAEs of ±4.53 years for Belleville and ±3.77 years for modern individuals. There were no statistically significant differences in age estimations between modern and archaeological individuals, or with respect to tooth type, sex, or intra/inter-observer estimations. DISCUSSION This study provides a new more accurate method for estimating age-at-death, particularly for individuals in the 50+ age category. Sectioning the teeth and directly measuring exposed pulp chambers results in age estimations that were within ±4.15 years for both modern and archaeological individuals, thus presenting a method that will enhance the ability to age older individuals.

Maintaining mobility after fracture: A biomechanical analysis of fracture consequences at the Roman Sites of Ancaster (UK) and Vagnari (Italy)

OBJECTIVE This study uses biomechanical data from tibiae to investigate the functional consequences of lower limb fractures. Adults with malunited fractures are hypothesized to have experienced altered mobility, indicated by asymmetric tibial cross-sectional geometries (CSG). MATERIALS Ninety-three adults from Roman (1st to 4th centuries CE) Ancaster, UK and Vagnari, Italy (Ancaster n = 16 adults with lower limb fracture:53 without fracture; Vagnari n = 5:19) METHODS: Biplanar radiographs were used to quantify and compare tibial CSG properties and asymmetries between individuals with and without fractures to femora, tibiae, and/or fibulae. The amount of angulation, rotation, and overlap, indicative of linear deformity, were measured for each fracture. Individuals who loaded their fractured leg differently than their opposite, uninjured leg were identified using outlying amounts of CSG asymmetry. RESULTS Two Ancaster individuals had poorly aligned fractures. None of the Ancaster or Vagnari individuals with lower limb fractures had CSG properties or asymmetries outside the calculated normal ranges. CONCLUSIONS Regardless of how a fracture healed, individuals at Ancaster and Vagnari generally resumed mobility after trauma whenever possible. SIGNIFICANCE This research contributes information about injury recovery and suggests that resilient behaviors and persistent mobility may have been valued or required responses to fracture in the study communities. This work advises that impairment should not be inferred based solely on the appearance of lesions. LIMITATIONS Site, sex, and age patterns in injury recovery are not evaluated due to sample size limitations. SUGGESTIONS FOR FURTHER RESEARCH Biomechanical assessments of post-traumatic function in varied cultural contexts are advised in order to further characterize the impact that physical and social factors have on injury recovery.

Analysis of patterning in the occurrence of skeletal lesions used as indicators of vitamin D deficiency in subadult and adult skeletal remains

Paleopathological investigations of conditions linked to vitamin D deficiency have increased in the last twenty years, and a suite of skeletal lesions has been established to aid in the diagnosis of vitamin D deficiency disease in subadults and adults. This paper analyzes the occurrence of these lesions in a large skeletal series comprising 3541 Roman period individuals (1st-6th century AD). Sixteen lesions reported in rickets in subadults, and 13 associated with residual rickets and osteomalacia in adults, were analyzed. Among subadults, there were clear associations among post-cranial lesions. Porotic cranial changes were associated with each other, but not with post-cranial lesions. A range of conditions could have produced the cranial lesions. There was a general paucity of correlations between indicators found in adults, and the difficulty in recording bending deformities was clear. Pseudofractures appear to provide a useful means of investigating osteomalacia in adults. In general, a simple algorithmic approach using presence or absence of lesions is unlikely to provide an adequate means of diagnosing vitamin D deficiency in paleopathology. Knowledge and consideration of the underlying physiological mechanisms involved in lesion formation, combined with individual judgement, will be required to differentially diagnose cases.

Latitude, urbanization, age, and sex as risk factors for vitamin D deficiency disease in the Roman Empire

OBJECTIVES The aims of the study are to investigate the effects of latitude, settlement type, age, and sex on the prevalence of vitamin D deficiency disease in the Roman Empire using human skeletal remains from cemetery sites (1st to 6th cent. AD). MATERIALS AND METHODS Data from 2,787 individuals (1,143 subadults, 1,644 adults) from 18 cemeteries associated with 15 different settlements in the Mediterranean and north-western Europe were analyzed. Vitamin D deficiency disease (rickets, osteomalacia) was identified using standard paleopathological criteria. Multivariate statistical analysis was used analyze the effects of the variables of interest on the prevalence of vitamin D deficiency. RESULTS The overall prevalence of rickets in subadults (<20 years) was 5.7%, and 3.2% of adults showed osteomalacia and/or residual rickets. There was a positive association between rickets in subadults and latitude, with numerous cases of rickets among infants. There was no general association with sex or settlement type, although an elevated prevalence of rickets was observed at a cemetery associated with a settlement (Ostia, Italy), which had multi-storey buildings. DISCUSSION The association of rickets with latitude may reflect care practices that, in more northerly locations where solar radiation is less intense, placed infants at increased risk of insufficient sunlight exposure to permit adequate vitamin D biosynthesis. The elevated level of vitamin D deficiency at Ostia may reflect, at least in part, the lack of sunlight due to dense occupation of multi-storey blocks that prevented direct sunlight from reaching living quarters and the streets between these closely spaced buildings.