Multiproxy isotopic analyses of human skeletal material from Rapa Nui: Evaluating the evidence from carbonates, bulk collagen, and amino acids.

OBJECTIVES: Stable isotope ratio analysis of bulk bone collagen dominates research into past diet; however, bone carbonate and compound specific isotope analyses (CSIA) of amino acids provide alternative, yet complementary, lines of evidence toward that same research goal. Together they inform on different aspects of diet, allowing greater certainty in reconstructions. Here we present new data on carbonate isotopes for Rapa Nui and reevaluate prehistoric diet in the context of these new and previously published bulk collagen and CSIA data. MATERIALS AND METHODS: We analyzed carbon isotopes in bone carbonate from 28 prehistoric human teeth from Rapa Nui. These represent a subset of material examined previously for carbon and nitrogen isotope ratios in bulk collagen. We then reevaluate prehistoric diet in light of these and other published data. In addition, we analyzed carbon and nitrogen isotope ratios in 28 modern plant specimens from Rapa Nui to better approximate the isotopic value of the terrestrial endmember. RESULTS: Bulk data suggest a predominantly terrestrial diet, with the amount of marine sources incorporated varying though time. While previously argued to reveal greater amounts of marine consumption, reanalysis of recently published CSIA data suggests this result may relate to the proportion of carbon assimilated rather than consumed. Utilizing models incorporating concentration dependence for estimating dietary proportions results in much lower estimates of marine consumption, in line with findings of the bulk data. DISCUSSION: While these data indicate a larger focus on terrestrial resources, limitations in all forms of analysis make it difficult to determine exact dietary contributions in this mixed system. Better understanding of the complex physiological processes governing isotopic routing and fractionation, and knowledge of appropriate isotopic endmember values are needed to advance this research.

Dorset Pre-Inuit and Beothuk foodways in Newfoundland, ca. AD 500-1829.

Archaeological research on the Canadian island of Newfoundland increasingly demonstrates that the island's subarctic climate and paucity of terrestrial food resources did not restrict past Pre-Inuit (Dorset) and Native American (Beothuk) hunter-gatherer populations to a single subsistence pattern. This study first sought to characterize hunter-gatherer diets over the past 1500 years; and second, to assess the impact of European colonization on Beothuk lifeways by comparing the bone chemistry of Beothuk skeletal remains before and after the intensification of European settlement in the early 18th century. We employed radiocarbon dating and stable carbon and nitrogen isotope ratio analysis of bulk bone collagen from both Dorset (n = 9) and Beothuk (n = 13) cultures, including a naturally mummified 17th century Beothuk individual. Carbon and nitrogen isotope analysis of 108 faunal samples from Dorset and Beothuk archaeological sites around the island were used as a dietary baseline for the humans. We combined our results with previously published isotope data and radiocarbon dates from Dorset (n = 12) and Beothuk (n = 18) individuals and conducted a palaeodietary analysis using Bayesian modelling, cluster analysis and comparative statistical tests. Dorset diets featured more marine protein than those of the Beothuk, and the diets of Beothuk after the 18th century featured less high trophic level marine protein than those of individuals predating the 18th century. Despite inhabiting the same island, Dorset and Beothuk cultures employed markedly different dietary strategies, consistent with interpretations of other archaeological data. Significantly, European colonization had a profound effect on Beothuk lifeways, as in response to the increasing European presence on the coast, the Beothuk relied more extensively on the limited resources of the island's boreal forests and rivers.

Breastfeeding, weaning, and dietary practices during the Western Zhou Dynasty (1122-771 BC) at Boyangcheng, Anhui Province, China.

OBJECTIVES: Here we investigate breastfeeding and weaning practices and adult dietary habits at the Western Zhou Dynasty (1122-771 BC) site of Boyangcheng () located in Anhui Province, China. In addition, we utilize the differences in bone collagen turnover rates between rib and long bones from the same individual to examine past life histories, such as changes in diet or residence. MATERIALS AND METHODS: Bone collagen from both the rib and long bones (either femora or humeri) of 42 individuals was measured for stable isotope ratios of carbon (δ13 C) and nitrogen (δ15 N). In addition, δ13 C and δ15 N values are reported for 35 animals (dogs, cows, horses, pigs, and deer). RESULTS: The human δ13 C values range from -20.7‰ to -12.0‰ with a mean value of -18.8 ± 1.6‰. The human δ15 N values range from 9.1‰ to 13.4‰ with a mean value of 10.9 ± 1.0‰. The animals display a wide range of δ13 C (-21.5‰ to -8.2‰; -15.8 ± 4.5‰) and δ15 N values (4.0‰ to 9.5‰; 6.5 ± 1.8‰). CONCLUSIONS: The adult δ13 C and δ15 N results indicate that mixed C3 (rice) and C4 (millet) terrestrial diets with varying levels of animal protein (mostly pigs and deer) were consumed. The elevated subadult δ15 N results return to adult levels by approximately 3-4 years of age, indicating that the weaning process was completed during this period. Individuals between 2 and 10 years old, with lower δ13 C and δ15 N results than the adult mean, possibly consumed more plant-based diets, and this is consistent with Chinese medical teachings ∼1500 years later during the Tang Dynasty (AD 618-907). The isotopic offsets between the ribs and long bones revealed that five adults experienced dramatic dietary shifts in their later lives, switching from predominately C3 /C4 to C3 diets. This research provides the first isotopic information about ancient Chinese breastfeeding and weaning practices and establishes a foundation for future studies to examine diachronic trends.

Neolithic cultivation of water chestnuts (Trapa L.) at Tianluoshan (7000-6300 cal BP), Zhejiang Province, China.

Water chestnuts (Trapa) are frequently recovered at Neolithic sites along the Lower Yangtze River Valley and have been important components of the diets of prehistoric people. However, little systematic research has been conducted to determine their cultural and dietary importance. Excavations at the Tianluoshan site produced large quantities of well-preserved specimens, which provide an excellent collection for studying morphological changes with time. Using modern wild and domesticated water chestnuts (n = 447) as a reference, we find Neolithic samples (n = 481) at Tianluoshan are similar in shape but smaller in size compared to the domesticated species Trapa bispinosa. In particular, the Tianluoshan water chestnuts have bigger seeds than the wild species Trapa incisa. Further, water chestnuts diachronically increased in size at the Tianluoshan site with significant differences (one-way, ANOVA) observed for length (p = 7.85E-08), height (p = 3.19E-06), thickness (p = 1.2E-13), top diameter (p = 5.04E-08) and bottom diameter (p = 1.75E-05) between layers 7 (6700-6500 cal BP) and 6 (6500-6300 cal BP). These results suggest that water chestnuts were actively selected based on size (big), shape (full fruit, two round horns, wide base, etc.) and were an important non-cereal crop to the agricultural practices at the Tianluoshan site.

Tracing the locality of prisoners and workers at the Mausoleum of Qin Shi Huang: First Emperor of China (259-210 BC).

The mausoleum complex of the First Emperor of China, Qin Shi Huang (259-210 BC), is one of the most famous and important archaeological sites in China, yet questions remain as to how it was constructed and by whom. Here we present isotopic results of individuals from the Liyi (n = 146) and Shanren sites (n = 14), both associated with the mausoleum complex. Those buried at Liyi represent the local workers/inhabitants of the Qin population, and the δ(13)C (-8.7 ± 1.5%) and δ(15)N (10.3 ± 0.7%) values indicate that they consumed predominately millet and/or domestic animals fed millet. In contrast, the Shanren individuals were prisoners forced to construct the mausoleum (found buried haphazardly in a mass grave and some in iron leg shackles), and their δ(13)C (-15.4 ± 2.9%) and δ(15)N (8.0 ± 0.6%) results indicate a more mixed C3/C4 diet, with possibly less domestic animals and more wild game protein consumed. This pattern of decreased millet consumption is also characteristic of archaeological sites from southern China, and possible evidence the Shanren prisoners originated from this region (possibly the ancient Chu state located in modern day Hubei Province and parts of Hunan and Anhui Provinces). Further, this finding is in agreement with historical sources and is supported by previous ancient DNA evidence that the mausoleum workers had diverse origins, with many genetically related to southern Chinese groups.

Isotopic perspectives (δ(13) C, δ(15) N, δ(34) S) of diet, social complexity, and animal husbandry during the proto-shang period (ca. 2000-1600 BC) of China.

OBJECTIVES: To examine dietary patterns and animal husbandry practices and assess the links between human diet and sex, age, burial direction/position, and social status (as inferred by type of grave goods) during the transformative Proto-Shang (ca. 2000-1600 BC) period of China. MATERIALS AND METHODS: Stable isotope ratios of carbon (δ(13) C), nitrogen (δ(15) N), and sulfur (δ(34) S) were analyzed from human (n = 83) and animal (n = 36) bone collagen at the site of Nancheng in Hebei Province, China. RESULTS: The Proto-Shang population consumed a predominately C4 diet (δ(13) C = -6.8 ± 0.4‰; δ(15) N = 9.4 ± 0.6‰), but a single individual (M70) had a mixed C3 /C4 diet (δ(13) C = -14.9‰; δ(15) N = 10.1‰). The δ(34) S measurement of M70 (8.8‰) is similar to the local animals (8.2 ± 2.6‰) and the other members of the population (7.0 ± 0.8‰) suggesting this individual may not have been a migrant even though the burial direction (north-south) and position (flexed) was different than the majority of the graves in the cemetery. DISCUSSION: From comparison with the faunal bone collagen stable isotope results, the Nancheng population ate millets with varying levels of animal protein consumption focused primarily on pigs and possibly cattle and dogs, but sheep/goats, and deer were not eaten in significant amounts. Analysis of the isotopic results in relation to other contemporary sites such as Liuzhuang and Xinzhai show strikingly similar patterns, suggesting that the sheep/goats were likely raised mainly for their secondary products (e.g., wool). No link between diet and sex was found at the population level, but when the data were sorted by age and sex, the older males (>40 years old) were found to have significantly lower δ(13) C values (-6.6 ± 0.3‰; n = 18) compared to the younger males (<40 years old) (-7.3 ± 0.5‰; n = 8). Further, no significant correlations between diet and burial direction/position or social status (based on the type of grave goods) were found at Nancheng, possibly indicating that the dietary social stratification of the later Shang and Zhou Dynasties had yet to be established in Chinese society at this time. Am J Phys Anthropol 160:433-445, 2016.. © 2016 Wiley Periodicals, Inc.

The genetic prehistory of the New World Arctic.

The New World Arctic, the last region of the Americas to be populated by humans, has a relatively well-researched archaeology, but an understanding of its genetic history is lacking. We present genome-wide sequence data from ancient and present-day humans from Greenland, Arctic Canada, Alaska, Aleutian Islands, and Siberia. We show that Paleo-Eskimos (~3000 BCE to 1300 CE) represent a migration pulse into the Americas independent of both Native American and Inuit expansions. Furthermore, the genetic continuity characterizing the Paleo-Eskimo period was interrupted by the arrival of a new population, representing the ancestors of present-day Inuit, with evidence of past gene flow between these lineages. Despite periodic abandonment of major Arctic regions, a single Paleo-Eskimo metapopulation likely survived in near-isolation for more than 4000 years, only to vanish around 700 years ago.

Investigation of diachronic dietary patterns on the islands of Ibiza and Formentera, Spain: evidence from sulfur stable isotope ratio analysis.

We present sulfur isotope ratio measurements of bone collagen from animals (n = 75) and humans (n = 120) from five sites dating to four chronological periods (Chalcolithic, Punic, Late Antiquity-Early Byzantine, and Islamic) from the Balearic Islands of Ibiza and Formentera, Spain. This study is a follow up to previously published δ(13)C and δ(15)N values by [Fuller et al.: Am J Phys Anthropol 143 (2010) 512-522] and focuses on using δ(34)S values to better understand the dietary patterns of these populations through time and to possibly identify immigrants to these islands. The range of δ(34)S values (10.5-17.8‰) observed for the animals was relatively broad, which suggests that a significant sea spray effect has added marine sulfates to the soils of Formentera and Ibiza. The mean δ(34)S values of the different human populations were found to be: Chalcolithic (16.5 ± 1.4‰), Punic rural (13.6 ± 1.7‰), Punic urban (12.9 ± 1.8‰), Late Antiquity-Early Byzantine (12.3 ± 2.1‰), and Islamic (9.1 ± 2.7‰). These human δ(34)S results are similar to the animal data, a finding that supports the notion that there was little marine protein consumption by these societies and that the diet was mainly based on terrestrial resources. During the Punic and Late Antiquity-Early Byzantine periods the δ(34)S values were used to identify individuals in the population who likely were not born or raised on the islands. In addition, 18 of the 20 individuals analyzed from the Islamic period have δ(34)S values that indicate that they were immigrants to Ibiza who died before acquiring the new local sulfur isotopic signature.

Investigation of diachronic dietary patterns on the islands of Ibiza and formentera, Spain: Evidence from carbon and nitrogen stable isotope ratio analysis.

To examine how dietary patterns may have changed in the western Mediterranean through time, stable carbon and nitrogen isotope ratios were measured on extracted bone collagen from fauna (n = 75) and humans (n = 135) spanning four distinct chronological periods: Chalcolithic (c.2100-1600 BC), Punic (6th-2nd/1st century BC), Late Antiquity-Early Byzantine (4th-7th century AD), and Islamic (c.10th-13th century AD) on the islands of Ibiza and Formentera, Spain. The Chalcolithic, Punic, and Late Antiquity-Byzantine societies all showed evidence of a predominately C(3) terrestrial-based diet with a possible input of a small amount of marine and/or C(4) dietary resources. In contrast, the Islamic population on Ibiza had a subsistence strategy that was reliant on a significant amount of C(4) plants and/or animals fed a C(4) diet, likely millet. These results indicate a fairly constant C(3) terrestrial-based diet on the islands of Ibiza and Formentera through time, with a shift to C(4) dietary resources during the Islamic Period. Further research is needed from other Islamic populations in and around the Mediterranean to better understand this unique dietary adaptation. Am J Phys Anthropol 143:512-522, 2010. © 2010 Wiley-Liss, Inc.