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Michael P Richards - One of the best experts on this subject based on the ideXlab platform.
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comparison of two methods of extracting bone collagen for stable carbon and Nitrogen Isotope analysis comparing whole bone demineralization with gelatinization and ultrafiltration
Journal of Archaeological Science, 2014Co-Authors: Judith Sealy, Malia Johnson, Michael P Richards, Olaf NehlichAbstract:We compare two methods of isolating bone collagen for stable carbon and Nitrogen Isotope analysis. The older method (as practised at the University of Cape Town) demineralizes bone ‘chunks’, while the newer method (as practised at the Max Planck Institute for Evolutionary Anthropology in Leipzig) involves demineralization, gelatinization and ultra-filtration to select only higher molecular weight protein fragments for isotopic analysis. The latter method was developed for problematic (i.e. poorly-preserved) samples and while it is more rigorous, it is also significantly more expensive and more labor-intensive. Our aim is to find out whether there is any difference between the δ13C and δ15N of bone collagen isolated from relatively well-preserved bones using the two methods. Our sample set consists of 5 modern and 47 archaeological animal and human bones from the southern and western parts of South Africa. Archaeological specimens range in age from a few hundred to approximately six thousand years old. Collagen was extracted, its quality assessed using %C, %N and C:N, and δ13C and δ15N values measured independently in both laboratories. There are no statistically significant differences between the sets of δ13C and δ15N values from the two laboratories. For relatively well-preserved bones, the ‘chunk’ method of collagen preparation continues to be an acceptable alternative to more sophisticated collagen extraction protocols for C and N Isotope analysis.
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stable Nitrogen Isotope analysis of dentine serial sections elucidate sex differences in weaning patterns of wild chimpanzees pan troglodytes
American Journal of Physical Anthropology, 2014Co-Authors: Geraldine E Fahy, Michael P Richards, Benjamin T Fuller, Tobias Deschner, Jeanjacques Hublin, Christophe BoeschAbstract:Offspring provisioning is one of the most energetically demanding aspects of reproduction for female mammals. Variation in lactation length and wean- ing strategies between chimpanzees (Pan troglodytes), our closest living relative, and modern human societies have been reported. When and why these changes occurred is frequently debated. Our study used stable Nitrogen Isotope data of tooth root dentine from wild Western chimpanzees (Pan troglodytes verus )i n Ta€i National Park, C^ d'Ivoire, to quantify weaning in these chimpanzees and explore if infant sex plays a role in maternal investment. We ana- lyzed serial sections of deciduous lateral incisor root den- tine from four Ta€ chimpanzees to establish the d 15 N signal of nursing infants; we then analyzed serial sections of first permanent mandibular molar root dentine from 12 Ta€i chimpanzees to provide quantitative d 15 Nd ata on weaning in this population. Up to 2 years of age both sexes exhibited dentine d 15 Nv alues2-3& higher than adult female Ta€i chimpanzees, consistent with a nursing signal. Thereafter a steady decrease in d 15 N values con- sistent with the onset, and progression, of weaning, was visible. Sex differences were also evident, where male d 15 N values decreased at a significantly slower rate com- pared to females. Confirmation of sex differences in mater- nal investment among Ta€i chimpanzees, demonstrates the viability of using Isotope analysis to investigate weaning in non-human primates. Additionally, assuming that behaviors observed in the Ta€i chimpanzees are illustrative of the ancestral pattern, our results provide a platform to enable the trajectory of weaning in human evolution to be further explored. Am J Phys Anthropol 153:635-642,
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sulphur Isotope evidence for freshwater fish consumption a case study from the danube gorges se europe
Journal of Archaeological Science, 2010Co-Authors: Olaf Nehlich, Michael P Richards, Dusan Boric, Sofija StefanovicAbstract:Abstract To explore the use of sulphur Isotopes as an indicator of the consumption of freshwater fish, we undertook sulphur Isotope analysis on bone collagen extracted from humans and animals from five archaeological sites from the Danube Gorges region dating from the Mesolithic to the middle Neolithic periods. The results show a difference in the sulphur Isotope values between freshwater and terrestrial ecosystems of 8.7‰. To reconstruct human diets, bone collagen from 24 individuals was analysed for carbon, Nitrogen and sulphur isotopic values. The Nitrogen Isotope ratios ranged from 10.3 to 16.5‰ and the carbon Isotope ratios ranged from −20.8 to −18.3‰. Low Nitrogen Isotope values were found for individuals with low sulphur Isotope ratios reflecting the low sulphur isotopic values of the terrestrial animals. The highest human Nitrogen Isotope values coincided with higher sulphur Isotope ratios, which are related to the higher sulphur Isotope values of the freshwater fish. Intermediate human sulphur isotopic ratios between these two extremes showed mixed diets of both terrestrial and freshwater resources.
Amy Bogaard - One of the best experts on this subject based on the ideXlab platform.
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Nitrogen Isotope values of Pennisetum glaucum (pearl millet) grains: towards a reconstruction of past cultivation conditions in the Sahel, West Africa
Vegetation History and Archaeobotany, 2019Co-Authors: Amy K. Styring, Amy Bogaard, Amadou M. Diop, Louis Champion, Dorian Q. Fuller, Nikolas Gestrich, Kevin C. Macdonald, Katharina NeumannAbstract:The Nitrogen Isotope compositions of charred wheat and barley grains reflect manuring intensity and have been used to reconstruct past manuring practices at archaeological sites across Europe and western Asia. To assess whether this analytical method can be applied to a staple crop in the West African Sahel, the Nitrogen Isotope values of Pennisetum glaucum grains in this region were determined and the effect of charring ascertained. Pennisetum glaucum ears were collected from fields in northeast Senegal, where the fertilisation histories of the plots (manure and/or household waste) were known. The Nitrogen Isotope values of these millet grains provide an insight into the values to expect for P. glaucum grains grown with low to moderate addition of manure/household waste in a semi-arid climate. Charring of P. glaucum grains by heating at 215–260 °C for 4–24 h increases their Nitrogen Isotope values by a maximum of 0.34‰. In light of these modern data, the Nitrogen Isotope values of millet grains recovered from the archaeological settlement mound of Tongo Maaré Diabal, Mali, can be interpreted as evidence for modest levels of manure/household waste input throughout the occupation of the site from cal ad 500–1150. This study demonstrates the potential for Nitrogen Isotope values of P. glaucum grains to shed light on past farming practices in West Africa.
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Nitrogen Isotope values of Pennisetum glaucum (pearl millet) grains: towards a reconstruction of past cultivation conditions in the Sahel, West Africa
Vegetation History and Archaeobotany, 2019Co-Authors: Amy K. Styring, Amy Bogaard, Amadou M. Diop, Louis Champion, Dorian Q. Fuller, Nikolas Gestrich, Kevin C. Macdonald, Katharina NeumannAbstract:The Nitrogen Isotope compositions of charred wheat and barley grains reflect manuring intensity and have been used to reconstruct past manuring practices at archaeological sites across Europe and western Asia. To assess whether this analytical method can be applied to a staple crop in the West African Sahel, the Nitrogen Isotope values of Pennisetum glaucum grains in this region were determined and the effect of charring ascertained. Pennisetum glaucum ears were collected from fields in northeast Senegal, where the fertilisation histories of the plots (manure and/or household waste) were known. The Nitrogen Isotope values of these millet grains provide an insight into the values to expect for P. glaucum grains grown with low to moderate addition of manure/household waste in a semi-arid climate. Charring of P. glaucum grains by heating at 215–260 °C for 4–24 h increases their Nitrogen Isotope values by a maximum of 0.34‰. In light of these modern data, the Nitrogen Isotope values of millet grains recovered from the archaeological settlement mound of Tongo Maare Diabal, Mali, can be interpreted as evidence for modest levels of manure/household waste input throughout the occupation of the site from cal ad 500–1150. This study demonstrates the potential for Nitrogen Isotope values of P. glaucum grains to shed light on past farming practices in West Africa.
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Stable carbon and Nitrogen Isotope analysis at Neolithic Çatalhöyük: evidence for human and animal diet and their relationship to households
Journal of Archaeological Science, 2015Co-Authors: Jessica Pearson, Simon Hillson, Amy Bogaard, Nerissa Russell, Clark Spencer Larsen, Michael Charles, Katheryn C. TwissAbstract:The long-term excavations at Catalhoyuk, a Neolithic site in central Turkey, have uncovered over 100 houses, which have been associated with at least 400 human skeletons and one million recorded animal bones. This large assemblage has enabled an extensive programme of stable carbon and Nitrogen Isotope analysis, which was designed to explore animal hunting and herding practices and how human diet varied according to age, sex, burial practice, location and over time. The Isotope values for sheep and cattle show how both were herded in a range of locations which consisted of pure C3 and also mixed C3/C4 plant locations. We sampled animals from middens adjacent to the buildings where people were buried to provide house-by-house diet reconstruction. However, very few of the people buried in the houses demonstrate a clear dietary relationship to these associated middens. Similarly, people buried in the same house seem to have had different diets to one another. We argue that these data suggest diet at Neolithic Catalhoyuk was a carefully structured, long-lived and repetitious process and that houses may not have functioned as the simple domestic units that they are often assumed to be.
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the impact of manuring on Nitrogen Isotope ratios in cereals archaeological implications for reconstruction of diet and crop management practices
Journal of Archaeological Science, 2007Co-Authors: Amy Bogaard, Tim H E Heaton, P R Poulton, Ines MerbachAbstract:Abstract Recent archaeological studies of human diet have used stable Nitrogen Isotope ratios ( δ 15 N) from human bone collagen to infer the relative importance of terrestrial plant and animal foods. This approach is based on widely observed enrichment of δ 15 N up the food chain, plants having distinctly lower values than the herbivores that consume them. Studies of early farming diets in Britain, Denmark and Germany have tended to detect relatively high δ 15 N values (e.g. c. +9‰), interpreted as evidence of a diet largely based on animal products, though archaeobotanical evidence for crop cultivation (e.g. carbonised cereal grain and chaff) is widespread. This paper investigates the impact of manuring on δ 15 N values in modern cereals, and of charring on these cereal values. The results from two long-term experiments demonstrate that manuring significantly raises δ 15 N in cereal grain and chaff. Depending on manuring levels and frequency, it appears that human diets with a major component of such grain would conventionally be interpreted as indicating a largely animal-based diet or a mixed plant/animal diet. Moreover, preliminary analyses of experimentally charred grain and chaff from manured and unmanured conditions are promising for the extraction of reliable ancient δ 15 N values from archaeobotanical cereal remains. The wider implications of these results, and the need for further work, are discussed.
Katharina Neumann - One of the best experts on this subject based on the ideXlab platform.
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Nitrogen Isotope values of Pennisetum glaucum (pearl millet) grains: towards a reconstruction of past cultivation conditions in the Sahel, West Africa
Vegetation History and Archaeobotany, 2019Co-Authors: Amy K. Styring, Amy Bogaard, Amadou M. Diop, Louis Champion, Dorian Q. Fuller, Nikolas Gestrich, Kevin C. Macdonald, Katharina NeumannAbstract:The Nitrogen Isotope compositions of charred wheat and barley grains reflect manuring intensity and have been used to reconstruct past manuring practices at archaeological sites across Europe and western Asia. To assess whether this analytical method can be applied to a staple crop in the West African Sahel, the Nitrogen Isotope values of Pennisetum glaucum grains in this region were determined and the effect of charring ascertained. Pennisetum glaucum ears were collected from fields in northeast Senegal, where the fertilisation histories of the plots (manure and/or household waste) were known. The Nitrogen Isotope values of these millet grains provide an insight into the values to expect for P. glaucum grains grown with low to moderate addition of manure/household waste in a semi-arid climate. Charring of P. glaucum grains by heating at 215–260 °C for 4–24 h increases their Nitrogen Isotope values by a maximum of 0.34‰. In light of these modern data, the Nitrogen Isotope values of millet grains recovered from the archaeological settlement mound of Tongo Maaré Diabal, Mali, can be interpreted as evidence for modest levels of manure/household waste input throughout the occupation of the site from cal ad 500–1150. This study demonstrates the potential for Nitrogen Isotope values of P. glaucum grains to shed light on past farming practices in West Africa.
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Nitrogen Isotope values of Pennisetum glaucum (pearl millet) grains: towards a reconstruction of past cultivation conditions in the Sahel, West Africa
Vegetation History and Archaeobotany, 2019Co-Authors: Amy K. Styring, Amy Bogaard, Amadou M. Diop, Louis Champion, Dorian Q. Fuller, Nikolas Gestrich, Kevin C. Macdonald, Katharina NeumannAbstract:The Nitrogen Isotope compositions of charred wheat and barley grains reflect manuring intensity and have been used to reconstruct past manuring practices at archaeological sites across Europe and western Asia. To assess whether this analytical method can be applied to a staple crop in the West African Sahel, the Nitrogen Isotope values of Pennisetum glaucum grains in this region were determined and the effect of charring ascertained. Pennisetum glaucum ears were collected from fields in northeast Senegal, where the fertilisation histories of the plots (manure and/or household waste) were known. The Nitrogen Isotope values of these millet grains provide an insight into the values to expect for P. glaucum grains grown with low to moderate addition of manure/household waste in a semi-arid climate. Charring of P. glaucum grains by heating at 215–260 °C for 4–24 h increases their Nitrogen Isotope values by a maximum of 0.34‰. In light of these modern data, the Nitrogen Isotope values of millet grains recovered from the archaeological settlement mound of Tongo Maare Diabal, Mali, can be interpreted as evidence for modest levels of manure/household waste input throughout the occupation of the site from cal ad 500–1150. This study demonstrates the potential for Nitrogen Isotope values of P. glaucum grains to shed light on past farming practices in West Africa.
Minoru Yoneda - One of the best experts on this subject based on the ideXlab platform.
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quantitative reconstruction of weaning ages in archaeological human populations using bone collagen Nitrogen Isotope ratios and approximate bayesian computation
PLOS ONE, 2013Co-Authors: Takumi Tsutaya, Minoru YonedaAbstract:Background Nitrogen Isotope analysis of bone collagen has been used to reconstruct the breastfeeding practices of archaeological human populations. However, weaning ages have been estimated subjectively because of a lack of both information on subadult bone collagen turnover rates and appropriate analytical models. Methodology Temporal changes in human subadult bone collagen turnover rates were estimated from data on tissue-level bone metabolism reported in previous studies. A model for reconstructing precise weaning ages was then developed using a framework of approximate Bayesian computation and incorporating the estimated turnover rates. The model is presented as a new open source R package, WARN (Weaning Age Reconstruction with Nitrogen Isotope analysis), which computes the age at the start and end of weaning, 15N-enrichment through maternal to infant tissue, and value of collagen synthesized entirely from weaning foods with their posterior probabilities. The model was applied to 39 previously reported Holocene skeletal populations from around the world, and the results were compared with weaning ages observed in ethnographic studies. Conclusions There were no significant differences in the age at the end of weaning between the archaeological (2.80±1.32 years) and ethnographic populations. By comparing archaeological populations, it appears that weaning ages did not differ with the type of subsistence practiced (i.e., hunting–gathering or not). Most of -enrichment (2.44±0.90‰) was consistent with biologically valid values. The Nitrogen Isotope ratios of subadults after the weaning process were lower than those of adults in most of the archaeological populations (−0.48±0.61‰), and this depletion was greater in non-hunter–gatherer populations. Our results suggest that the breastfeeding period in humans had already been shortened by the early Holocene compared with those in extant great apes.
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quantitative evaluation of marine protein contribution in ancient diets based on Nitrogen Isotope ratios of individual amino acids in bone collagen an investigation at the kitakogane jomon site
American Journal of Physical Anthropology, 2010Co-Authors: Yuichi I Naito, Naohiko Ohkouchi, Yoshito Chikaraishi, Noah V Honch, Minoru YonedaAbstract:Nitrogen stable Isotopes analysis of indi- vidual bone collagen amino acids was applied to archeo- logical samples as a new tool for assessing the composi- tion of ancient human diets and calibrating radiocarbon dates. We used this technique to investigate human and faunal samples from the Kitakogane shell midden in Hokkaido, Japan (5,300-6,000 cal BP). Using compound- specific Nitrogen Isotope analysis of individual amino acids, we aimed to estimate i) the quantitative contribu- tion of marine and terrestrial protein to the human diet, and ii) the mean trophic level (TL) from which dietary protein was derived from marine ecosystems. Data were interpreted with reference to the amino acid trophic level (TLAA) model, which uses empirical amino acid d 15 N from modern marine fauna to construct mathemati- cal equations that predict the trophic position of organ- isms. The TLAA model produced realistic TL estimates for the Kitakogane marine animals. However, this model was not appropriate for the interpretation of human amino acid d 15 N, as dietary protein is derived from both marine and terrestrial environments. Hence, we devel- oped a series of relevant equations that considered the consumption of dietary resources from both ecosystems. Using these equations, the mean percentage of marine protein in the Kitakogane human diet was estimated to be 74%. Although this study is one of the first system- atic investigations of amino acid d 15 N in archeological bone collagen, we believe that this technique is ex- tremely useful for TL reconstruction, palaeodietary interpretation, and the correction of marine reservoir effects for radiocarbon dating. Am J Phys Anthropol 143:31-40, 2010. V
Olaf Nehlich - One of the best experts on this subject based on the ideXlab platform.
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comparison of two methods of extracting bone collagen for stable carbon and Nitrogen Isotope analysis comparing whole bone demineralization with gelatinization and ultrafiltration
Journal of Archaeological Science, 2014Co-Authors: Judith Sealy, Malia Johnson, Michael P Richards, Olaf NehlichAbstract:We compare two methods of isolating bone collagen for stable carbon and Nitrogen Isotope analysis. The older method (as practised at the University of Cape Town) demineralizes bone ‘chunks’, while the newer method (as practised at the Max Planck Institute for Evolutionary Anthropology in Leipzig) involves demineralization, gelatinization and ultra-filtration to select only higher molecular weight protein fragments for isotopic analysis. The latter method was developed for problematic (i.e. poorly-preserved) samples and while it is more rigorous, it is also significantly more expensive and more labor-intensive. Our aim is to find out whether there is any difference between the δ13C and δ15N of bone collagen isolated from relatively well-preserved bones using the two methods. Our sample set consists of 5 modern and 47 archaeological animal and human bones from the southern and western parts of South Africa. Archaeological specimens range in age from a few hundred to approximately six thousand years old. Collagen was extracted, its quality assessed using %C, %N and C:N, and δ13C and δ15N values measured independently in both laboratories. There are no statistically significant differences between the sets of δ13C and δ15N values from the two laboratories. For relatively well-preserved bones, the ‘chunk’ method of collagen preparation continues to be an acceptable alternative to more sophisticated collagen extraction protocols for C and N Isotope analysis.
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sulphur Isotope evidence for freshwater fish consumption a case study from the danube gorges se europe
Journal of Archaeological Science, 2010Co-Authors: Olaf Nehlich, Michael P Richards, Dusan Boric, Sofija StefanovicAbstract:Abstract To explore the use of sulphur Isotopes as an indicator of the consumption of freshwater fish, we undertook sulphur Isotope analysis on bone collagen extracted from humans and animals from five archaeological sites from the Danube Gorges region dating from the Mesolithic to the middle Neolithic periods. The results show a difference in the sulphur Isotope values between freshwater and terrestrial ecosystems of 8.7‰. To reconstruct human diets, bone collagen from 24 individuals was analysed for carbon, Nitrogen and sulphur isotopic values. The Nitrogen Isotope ratios ranged from 10.3 to 16.5‰ and the carbon Isotope ratios ranged from −20.8 to −18.3‰. Low Nitrogen Isotope values were found for individuals with low sulphur Isotope ratios reflecting the low sulphur isotopic values of the terrestrial animals. The highest human Nitrogen Isotope values coincided with higher sulphur Isotope ratios, which are related to the higher sulphur Isotope values of the freshwater fish. Intermediate human sulphur isotopic ratios between these two extremes showed mixed diets of both terrestrial and freshwater resources.