Dietary Reconstruction Research Articles

Isotopic equifinality and rethinking the diet of Australopithecus anamensis.

Australopithecus anamensis has comparable δ13 Cenamel values to Ardipithecus ramidus, and both have been characterized as C3 feeders in open woodland habitats similar to "savanna" chimps. Unlike Ar. ramidus and "savanna" chimps, A. anamensis shows a derived dentognathic morphology for tough foods and a dental microwear pattern similar to the C3 -C4 -mixed-feeding A. afarensis. Here I test the hypothesis that changing the variables (ε*enamel-diet , δ13 CC3, δ13 CC4 values) used to calculate the percentage of dietary C4 foods (%C4 diet) by 1-2‰ does not make a substantial difference for hominin diet reconstructions [van der Merwe, Masao, & Bamford, 2008, South African Journal of Science 104:153-155]. I estimate vegetation structures for A. anamensis with pedogenic carbonate and faunal enamel δ13 C values from the Pliocene Omo-Turkana Basin (4.2-3.9 Ma). I recalculate A. anamensis' %C4 diet based on new body size-dependent estimates of the ε*enamel-diet value and alternative δ13 CC3 and δ13 CC4 values. The Pliocene Omo-Turkana Basin shows evidence for dietary resources with a wide range of δ13 C values including canopy-driven 13 C depleted ground C3 foods. Alternative equation variables changed by 1-2‰ yield higher C4 estimates for A. anamensis (15-31%) than previously thought (0-10%). The choice of δ13 CC3 and δ13 CC4 values for estimating %C4 is not a perfunctory task and potentially explains the δ13 C isotopic equifinality of A. anamensis and "savanna" chimps. My integrative diet model reconciles the carbon isotopic data with the dentognathic and microwear evidence of A. anamensis' diet and suggests that "savanna" chimps are not proper dietary analogs of A. anamensis. A foraging strategy across heterogeneous habitats of the Pliocene Omo-Turkana Basin incorporating an array of 13 C-depleted and 13 C-enriched C3 foods and a portion of C4 resources may have served as one of the selective pressures for A. anamensis, the earliest habitual biped [van der Merwe et al., 2008, South African Journal of Science 104:153-155].

Sex- and status-based differences in medieval food preparation and consumption: dental microwear analysis at Trino Vercellese, Italy

Food preparation is of key importance in the medieval period where the manner of preparing ingredients had major sociocultural significance. We examine sex- and status-based differences in dental occlusal microwear from a human skeletal population from medieval Trino Vercellese, Italy, to assess intrapopulation differences in food preparation. We compare microwear results with previously reported stable carbon and nitrogen isotope data to determine the extent to which these two methods for dietary reconstruction correspond. Epoxy casts of second molars from 27 males and females of high- and low-status from medieval Trino Vercellese, Italy, were studied using field emission scanning electron microscopy. Feature tally, pit percentage, pit width, and striation width are compared between subgroups. Whereas previous isotopic data identified low-status males as outliers, dental microwear analysis indicates no differences in diet between the four sex- and status-based subgroups. However, the percentage of pitting is statistically different between males and females when status groups are pooled, with males exhibiting significantly higher values (p = 0.017). When sexes are pooled, low-status individuals are found to have significantly more features compared with high-status individuals (p = 0.030). This study demonstrates the applicability of dental microwear analysis for uncovering intra-group dietary patterns in socially stratified societies.

Middle Holocene menus: dietary reconstruction from coprolites at the Connley Caves, Oregon, USA

Multiproxy data from coprolites at the Connley Caves in central Oregon provide new evidence for diet, seasonal subsistence strategies, and human health during the middle and late Holocene. Macrobotanical, palynological, and faunal components show that plant taxa from wetland and dryland habitats functioned as dietary staples. Repeated and abundant representation of wetland resources coupled with small dryland seeds provide strong evidence for dietary continuity between ~ 5700 and 3200 calendar years ago. Seasonal availability of represented taxa indicates late summer and early fall habitation. Minimal evidence for parasitic infection and unusual constituents such as cordage raise questions regarding health and cultural behavior. As the first coprolite analysis for this time period in the northern Great Basin, this study contributes unique datasets that complement and clarify the regional understanding of hunter-gatherer settlement-subsistence strategies and food economy.

Incorporating intraspecific variation into dental microwear texture analysis.

Dental microwear texture analysis (DMTA) quantifies microscopic scar or wear patterns left on teeth by different foods or extraneous ingested items such as grit. It can be a powerful tool for deducing the diets of extinct mammals. Here we investigate how intraspecific variation in the dental microwear of macropodids (kangaroos and their close relatives) can be used to maximize the dietary signal inferable from an inherently limited fossil record. We demonstrate significant intraspecific variation for every factor considered here for both scale-sensitive fractal analysis and International Organization for Standardization surface texture analysis variables. Intraspecific factors were then incorporated into interspecific (dietary) analyses through the use of Linear Mixed Effects modelling, incorporating Akaike's Information Criterion to compare models, and testing models through independent cross-validation. This revealed that for each DMTA variable only a small number of intraspecific factors need to be included to improve differentiation between species. Including specimen as a random factor accounted for stochastic inter-individual variation, and facet, incorporated effects of sampling location. Intraspecific effects of ecoregion, microscope, tooth position and wear were often but not universally important. We conclude that models of microwear data that include intraspecific variation can improve the resolution of dietary reconstructions.

Dental microwear textures and dietary preferences of extant rhinoceroses (Perissodactyla, Mammalia)

Rhinoceroses were conspicuous elements in Cenozoic ecosystems, and studying the ecological behavior of extant species might unravel the ecology of their fossil kin. Microwear as a short-term recorder may detect subtle variations in the diet. Dental microwear texture analysis (DMTA) is extensively used to infer paleodiets. Yet, regarding ungulates, most microwear studies have been conducted on artiodactyls, and more particularly on ruminants (i.e., foregut fermenters), which may not be good models for hindgut fermenters, such as rhinoceroses. Moreover, rhinoceroses display a specific enamel ultrastructure with vertical Hunter–Schreger bands and a peculiar mastication cycle likely to impact tooth response to wear. Here, we studied the DMTA of the five extant rhinoceros species (17 specimens of Ceratotherium simum, four of Dicerorhinus sumatrensis, 21 of Diceros bicornis, 14 of Rhinoceros sondaicus, and 5 of Rhinoceros unicornis) and built up the present dataset. In parallel, we also compiled a taxon-based dataset of consumed plants for each rhinoceros species. Accordingly, we propose to reclassify the Indian rhinoceros (Rhinoceros unicornis) from mixed-feeder to variable grazer. Significant discrepancies were found between grinding and shearing facets on molars and between species on a given facet. Plotting the percentage of anisotropic specimens against that of complex specimens for each species discriminated well the different diets on both facets. This unprecedented dataset on rhinoceros texture microwear confronted to detailed diets appears critical for future diet reconstruction of fossil rhinocerotoids.

Oilseeds, spices, fruits and flavour in the Indus Civilisation

The exploitation of plant resources was an important part of the economic and social strategies of the people of the Indus Civilisation (c. 3200–1500 BCE). Research has focused mainly on staples such as cereals and pulses, for understanding these strategies with regards to agricultural systems and reconstructions of diet, with some reference to ‘weeds’ for crop processing models. Other plants that appear less frequently in the archaeobotanical record have often received variable degrees of attention and interpretation. This paper reviews the primary literature and comments on the frequency with which non-staple food plants appear at Indus sites. It argues that this provides an avenue for Indus archaeobotany to continue its ongoing development of models that move beyond agriculture and diet to think about how people considered these plants as part of their daily life, with caveats regarding taphonomy and culturally-contextual notions of function.

Dynamic homeostasis modeling of Zn isotope ratios in the human body.

Recent research performed on volunteers and patients suggested that diet, health, and basal metabolic rates (BMR) are factors controlling the bodily Zn isotope compositions (isotopic homeostasis). However, our poor understanding of the variability of Zn distribution among the different organs and fluids of the human body, and the ensuing isotope fractionation, limits the use of this isotopic system as a typical diagnostic tool for cancers and for past hominin diet reconstructions. Using box model calculations, we investigated the dynamics of Zn isotope variability in blood and other body tissues as well as the consistency of the hypothesis of heavy Zn isotope accumulation through time in the human body. We compare the results of the model with data obtained from control feeding experiments and from archeological samples. Model simulations indicate that the absence of an aging drift in non-circumpolar populations cannot be explained by their lower BMR. We argue that the drift observed in the blood of a circumpolar population results from a differential diet between young and older individuals in this population. When applied to the δ66Zn measured in blood, bones, or teeth, the present box model also offers insight into the isotope composition of the human diet, and therefore into its nature. Applying the model to isotopic observations on the remains of past hominins is a promising tool for diet reconstruction.

Isotopic analysis of the Blick Mead dog: A proxy for the dietary reconstruction and mobility of Mesolithic British hunter-gatherers

A single domestic dog (Canis familiaris) tooth was recovered from the Mesolithic site of Blick Mead in the Stonehenge landscape. As no human remains were recovered from the site, the dog tooth provides a potential proxy for reconstructing human diet. Previous studies have shown that domestic dogs often have similar δ13C and δ15N values to their human companions. Incremental dentine carbon and nitrogen isotope analysis and bulk enamel carbon, oxygen and strontium isotope analysis were obtained from the tooth to produce a life-history profile of the dog's diet and mobility. The δ13C and δ15N values indicate that there was little variation in the dog's diet between c.2 and 6 months of age. δ15N values range between +7.9 to +8.7‰, (mean +8.5‰), whereas δ13C values range between −21.3 and −20.5‰, (mean −20.9‰). These data suggest that the dog was consuming predominantly terrestrial herbivorous protein, with the possible inclusion of freshwater fish. The enamel 87Sr/86Sr ratio of 0.70796 can only be obtained from a chalk landscape, such as is found at Blick Mead and elsewhere in southern and southeastern Britain, or basalt terrains which are rare in southern Britain. The enamel δ18O(SMOW) value of 25.7‰ is not consistent with the dog residing at Blick Mead but appropriate contemporaneous data from dogs is currently lacking. The results are thus consistent with the dog originating in a chalk or possibly basaltic terrain elsewhere in Britain and Ireland or that the dog resided locally at a time when the climate was colder than present.

Seaweed fertilisation impacts the chemical and isotopic composition of barley: Implications for analyses of archaeological skeletal remains

Fertilisation with animal manure has been shown to affect crop chemical and isotopic composition, indicating that if manuring effects are not taken into account, there is a risk of overestimating consumer trophic levels in palaeodietary studies. The effect of fertilisation with seaweed, a common fertiliser in the past in coastal areas, has been the subject of several hypotheses, but until now has not been studied in this particular context.In this study the impact of fertilising bere, an ancient type of Scottish barley (Hordeum vulgare L.), with 25 t/ha and 50 t/ha seaweed, in comparison to a modern commercial mineral fertiliser and to no fertilisation, was investigated in a field trial on the Orkney Islands, Scotland. Stable isotope ratios (δ13C and δ15N) and elemental concentrations (B, Mg, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Mo, Cd and Pb) of grain, husk and straw samples were determined. Significant differences were found between treatment groups, including increases in δ15N values of 0.6 ± 0.5‰ (average ± 1σ for five replicate plots) in grain, and 1.1 ± 0.4‰ in straw due to seaweed fertilisation. Elevated concentrations of Sr in grain and husk samples (factors of 1.2–1.4) indicate the geographic tracer 87Sr/86Sr may also be affected.Fertilisation with seaweed thus needs to be considered for archaeological interpretations of chemical and isotopic compositions of crop and skeletal material for accurate palaeodietary and provenance reconstructions, particularly in coastal areas. Further implications of these results for studies concerning the effects of sea spray, radiocarbon-dating, and for dietary reconstructions using trace elements are also identified.

Resource use by and trophic variability of Armases cinereum (Crustacea, Brachyura) across human-impacted mangrove transition zones.

In Florida, resource use patterns by Armases cinereum (Armases), a highly abundant crab in coastal habitats, may serve as important indicators of habitat condition. Here we investigated feeding patterns of Armases in coastal palm scrub forest to intertidal mangrove forest transition zones (transitions) as well as the relationship between habitat disturbance and Armases’ trophic position across three pairs of geographically separated populations in Tampa FL, USA. Each pair of sites represented an unmodified “natural” location as well as a “disturbed” location lacking upland terrestrial palm scrub forested habitat. Laboratory experiments established a baseline understanding of feeding preference of Armases offered strictly mangrove material as well as sources abundant at the transition. In-situ feeding behavior was examined using MixSIAR mixing models with δ13C and δ15N stable isotope tracers. Armases showed a strong preference for consuming partially-decomposed mangrove material from Avicennia germinans and an equally strong preference for Iva frutescens. Armases also displayed predatory behavior under laboratory conditions, confirming omnivory in the presence of mangrove material. Stable isotopes revealed a pattern of elevated trophic position of Armases in disturbed habitats over paired natural locations. Diet reconstruction provided coarse resolution of in-situ feeding and results show high spatial variation: in natural habitats, Armases appears to rely heavily upon upland plant material compared to disturbed habitats where it may consume more animal prey. Combined, these findings support that Armases trophic position and diet may indicate habitat quality in mangrove transitions in the southeastern United States.

Eneolithic subsistence economy in Central Italy: first dietary reconstructions through stable isotopes

The paper aims to point out the subsistence in Eneolithic Central Italian communities by Stable Isotope Analysis. This period marked a tipping point in the food strategies because it was characterized by economic changes and several technological improvements leading to enhance land exploitation and livestock breeding. Carbon and nitrogen stable isotope analysis has been used to analyze the food consumption of 54 people belonging to 5 Eneolithic communities scattered throughout Central Italy, where no data have yet been published. The estimation of the main protein intake has been achieved in order to quantify the differences among these communities. The results are consistent with a diet mainly based on terrestrial resources, with no exclusive marine sources consumption, although their occasional usage cannot be ruled out, especially for selected funerary contexts. The data suggest an overall subsistence based on greater local resource procurement, supported by regional productivity maximization. A roughly homogeneous landscape could be outlined in Tuscany and Marche communities witnessing a shared diet preference that could be modified by local preferences. The fully developed trade routes between the two sides of the Apennines could address the overall dietary homogeneity of the studied communities, especially between Fontenoce di Recanati and the southern Tuscan human groups such as Grotta del Fontino and Buca di Spaccasasso, with lesser influence for Le Lellere and Podere Cucule that seem to suggest a more locally based subsistence, even though the funerary affinities do not match this overall diet homogeneity.

Dietary habits in the Early Bronze Age (3rd millennium BC) of Anatolia: A multi-isotopic approach

This paper presents the results of isotopic analysis for dietary reconstruction of humans and animal remains from several prehistoric (3500–2000 BCE) populations in Anatolia. The investigated sites are İkiztepe (north Anatolia, Samsun region, on the Black Sea coast), Titriş Höyük (south east Anatolia, Urfa region), Bademağacı (south Anatolia, Antalya region), and Bakla Tepe (south west Anatolia, in the İzmir region). This research utilises the results of stable isotope analyses of carbon (δ13C), nitrogen (δ15N), and sulphur (δ34S) in bone collagen from over 200 human and animal samples in conjunction with published archaeological, archaeobotanical, and archaeozoological data (where present) to address this issue. This study, for the first time, has permitted a wider observation of Early Bronze Age dietary habits and subsistence strategies across the region, as well as examining the nature of dietary habits on an intra- and inter-site level, and temporally across the 3rd millennium BC. The results show that during the EBA in Anatolia there was a general degree of homogeneity in dietary habits at an intra- and inter-site and regional level and across the millennium of the EBA with diets being predominantly terrestrial C3 based.

The medieval population of Leopoli-Cencelle (Viterbo, Latium): Dietary reconstruction through stable isotope analysis from bone proteins

The Medieval period in Europe was a time of unprecedented social complexity and significant social and political change that had an impact on human diets. The present study aims to use stable isotope analysis from bone proteins to explore the diets of humans (n = 76) and fauna (n = 5) from the Medieval town of Leopoli-Cencelle (VT, Italy). The town was occupied between the 9th–15th centuries CE, however, the analysed remains date to the Late Medieval period (12th–15th centuries CE). Historical sources provide some information about the inhabitants of this community: the majority of the population was represented by craftsmen and traders, but farmers and shepherds were also present. To date, no biomolecular data regarding this community have been published.The results indicated an increase of 3–5‰ in δ15N values of humans compared to animals, reflecting a high trophic-level. The δ13C results indicated that animal and human diet was mainly based on C3 terrestrial resources, although three humans possessed an isotopic signature indicative of C4 plant consumption. No statistically significant differences between sexes or age groups (adults vs juveniles) were detected. The isotopic results were further placed in their regional and chronological context, adding valuable data to our understanding of diet and food distribution during the Medieval period in Italy.

Forage silica and water content control dental surface texture in guinea pigs and provide implications for dietary reconstruction

Recent studies have shown that phytoliths are softer than dental enamel but still act as abrasive agents. Thus, phytolith content should be reflected in dental wear. Because native phytoliths show lower indentation hardness than phytoliths extracted by dry ashing, we propose that the hydration state of plant tissue will also affect dental abrasion. To assess this, we performed a controlled feeding experiment with 36 adult guinea pigs, fed exclusively with three different natural forages: lucerne, timothy grass, and bamboo with distinct phytolith/silica contents (lucerne < grass < bamboo). Each forage was fed in fresh or dried state for 3 weeks. We then performed 3D surface texture analysis (3DST) on the upper fourth premolar. Generally, enamel surface roughness increased with higher forage phytolith/silica content. Additionally, fresh and dry grass feeders displayed differences in wear patterns, with those of fresh grass feeders being similar to fresh and dry lucerne (phytolith-poor) feeders, supporting previous reports that "fresh grass grazers" show less abrasion than unspecialized grazers. Our results demonstrate that not only phytolith content but also properties such as water content can significantly affect plant abrasiveness, even to such an extent that wear patterns characteristic for dietary traits (browser-grazer differences) become indistinguishable.

Carbon, nitrogen, and sulfur stable isotopic reconstruction of human diet in a mountainous woodland village in Sendaiji in premodern Japan

Carbon, nitrogen, and sulfur stable isotopic reconstruction of human diet in a mountainous woodland village in Sendaiji in premodern Japan

Тhe Reconstruction of the Traditional Peasant Diet of the Russian North according to Linguistic Data (with Reference to Oatmeal Dishes Names)

Тhe Reconstruction of the Traditional Peasant Diet of the Russian North according to Linguistic Data (with Reference to Oatmeal Dishes Names)

Does the native predator Trophon geversianus exert top-down control on the invasive barnacle Balanus glandula on Patagonian rocky shores?

Trophic interactions between the native gastropod predator Trophon geversianus and the invasive barnacle Balanus glandula may have facilitated the successful expansion of the barnacle along rocky intertidal coastlines in Argentina. In this study, through field observations and a stable isotope reconstruction of the diet of T. geversianus, we assessed whether and how frequently this drilling muricid gastropod consumes the invasive B. glandula on a Patagonian rocky shore. Field observations indicated that B. glandula and T. geversianus co-occur in the middle intertidal. Feeding observations and stable carbon and nitrogen isotope dietary reconstructions showed that T. geversianus readily and successfully consumes B. glandula, but at low rates (4% of diet) relative to native mussel prey, which compete with B. glandula for space. This study shows that T. geversianus exerts little top-down control on this invasive barnacle on Patagonian rocky shores. The success of B. glandula on these shores is plausibly enhanced directly by this weak interaction and indirectly by the preference of T. geversianus for native prey rather than the absence of predators or invader immunity from predation. The results of this study complement previous studies that have shown that tolerance to extreme desiccation stress in harsh intertidal environments is crucial for the establishment of B. glandula.

Stable carbon and nitrogen isotope inter- and intra-individual dietary reconstruction from the late 14th to early 18th century site of Alytus, Lithuania.

The Baltic region, particularly Lithuania, was a politically vibrant area of Eastern Europe during the medieval and early modern period. To better understand the diet of Lithuanians during the late 14th to early 18th century, we examine stable carbon and nitrogen isotope ratios from bone and dentin samples from the site of Alytus. We investigate possible dietary differences based on sex, age, and religious practice, as well as dietary changes throughout an individual's lifetime, within the broader European milieu. Stable carbon and nitrogen isotope analysis was conducted on bone (n = 35) and dentin (n = 38) collagen samples from a total of 39 individuals buried in the cemetery at Alytus (late 14th to early 18th centuries). Results indicate individuals at Alytus consumed a C3 terrestrial based diet. The δ13 C and δ15 N values are not significantly different between bone and dentin, and did not vary by sex. The diet at Alytus was homogeneous between males and females and between tissue types. The lack of evidence indicating substantial consumption of fish is unexpected given widespread Catholic fasting practices and marine resource trade throughout Europe. Comparisons with other populations indicate that individuals from Alytus differ in diet from contemporaneous Polish-Lithuanian Commonwealth elites. Comparison of the diets of non-elite individuals in the Eastern Baltic region also reveals dietary variability.

Coastal complexity: Ancient human diets inferred from Bayesian stable isotope mixing models and a primate analogue.

An extensive ecological literature applies stable isotope mixing models to derive quantitative dietary reconstructions from isotope ratios of consumer tissues. While this approach works well for some organisms, it is challenging for consumers with complex, varied diets, including humans; indeed, many archaeologists have avoided the use of mixing models because uncertainties in model outputs are sufficiently large that the findings are not helpful in understanding ancient lifeways. Here, we exploit an unparalleled opportunity to evaluate the feasibility of dietary quantification in a nutritionally and isotopically complex context on the Cape Peninsula, South Africa. Delta values (δ13C and δ15N) of 213 indigenous food samples enable us to characterise four food groups: terrestrial plants, terrestrial vertebrates, marine invertebrates and marine vertebrates. A recent study of baboons that consumed marine and terrestrial foods provides insight into the relationship between such foods and consumer tissue isotopes. We use this information to refine our interpretation of δ15N and especially δ13C in bone collagen from 35 archaeological hunter-gatherers, achieving better estimates of the relative importance of marine and terrestrial foods in the diet than has hitherto been possible. Based on Bayesian stable isotope mixing model (SIMM) outputs, we infer that the trophic enrichment factor (TEF) for δ13Cbone collagen in these coastal humans is closer to +3 than +5‰. In the most 13C- and 15N-rich individuals, 65–98% of bone collagen (95% credible intervals) derived from marine foods. Conversely, in 13C and 15N-poor individuals, 7–44% of bone collagen derived from marine foods. The uncertainties discussed here highlight the need for caution when implementing SIMMs in studies of consumers with complex diets. To our knowledge, this work constitutes the most detailed and most tightly constrained study of this problem to date.

A time of change: dietary reconstruction of the Merovingian cemetery of Norroy-le-Veneur, France.

The aim of this work was to analyse the diet of a Merovingian population sample of 80 individuals buried at Norroy-le-Veneur, France, with regard to their social status and chronology. A carbon and nitrogen stable isotope analysis of human adult bone collagen and related fauna from the same cemetery showed a diet based primarily on C3 plants, supplemented with animal protein in a range comparable to other contemporary sites. No significant contribution of C4 plants (e.g. millet) or marine-derived protein was detected. In terms of socio-economic stratification, individuals buried with rich grave good assemblages formed a narrow group with a significantly higher mean of δ13C than low-ranking individuals. We argue that this may represent a step in the gradual formation of the dietary exclusivity of Frankish elites, following a progressive rise in power of the Merovingian nobility. Also, during the timespan of the cemetery there was a population-wide decrease of 0.3 ‰ in the mean value of δ13C. The role of the Christian conversion of the population is questioned, but another factor influencing diet might have played a role.