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Funck J, Kellam C, Seaton CT, Wooller MJ. Stable isotopic signatures in modern wood bison (Bison bison athabascae) hairs as telltale biomarkers of nutritional stress. CAN J ZOOL 2020. [DOI: 10.1139/cjz-2019-0185] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Assessing the challenges faced by wildlife populations is key to providing effective management but is problematic when dealing with populations in remote locations. Analyses of the stable carbon and nitrogen isotope composition (expressed as δ13C and δ15N values) of sequentially grown tissues, such as hairs, can be used to track changes in the eco-physiology of organisms. We generated δ13C and δ15N values from sequentially sampled (n = 465) hairs taken from wood bison (Bison bison athabascae Rhoads, 1898) (n = 27). Samples were taken from individuals prior to and after their release from captivity into the lower Innoko–Yukon river area of Alaska in 2015. Twenty months after release, individuals had a distinct seasonal pattern in δ13C values. Hairs from individuals that experienced food scarcity or long-distance movement were sampled as case studies. Nutritional stress in these cases lead to a rise in δ15N values and a decrease in δ13C values. Applications of δ13C and δ15N analyses of bison tail hairs could provide wildlife managers a valuable and minimally invasive tool to better understand bison seasonal metabolic status and determine the historical health and behavior of living and dead individuals.
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Affiliation(s)
- Juliette Funck
- Department of Geology and Geoscience, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
- Alaska Stable Isotope Facility, Water and Environmental Research Center, Institute of Northern Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Cade Kellam
- Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - C. Tom Seaton
- Wood Bison Restoration Project, Alaska Department of Fish and Game, Fairbanks, AK 99701, USA
| | - Matthew J. Wooller
- Alaska Stable Isotope Facility, Water and Environmental Research Center, Institute of Northern Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
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Lazzerini N, Coulon A, Simon L, Marchina C, Noost B, Lepetz S, Zazzo A. Grazing high and low: Can we detect horse altitudinal mobility using high-resolution isotope (δ 13 C and δ 15 N values) time series in tail hair? A case study in the Mongolian Altai. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33:1512-1526. [PMID: 31148256 DOI: 10.1002/rcm.8496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/24/2019] [Accepted: 05/25/2019] [Indexed: 06/09/2023]
Abstract
RATIONALE Carbon and nitrogen stable isotope time series performed in continuously growing tissues (hair, tooth enamel) are commonly used to reconstruct the dietary history of modern and ancient animals. Predicting the effects of altitudinal mobility on animal δ13 C and δ15 N values remains difficult as several variables such as temperature, water availability or soil type can contribute to the isotope composition. Modern references adapted to the region of interest are therefore essential. METHODS Between June 2015 and July 2018, six free-ranging domestic horses living in the Mongolian Altaï were fitted with GPS collars. Tail hairs were sampled each year, prepared for sequential C and N isotope analysis using EA-IRMS. Isotopic variations were compared with altitudinal mobility, and Generalized Additive Mixed (GAMMs) models were used to model the effect of geographic and environmental factors on δ13 C and δ15 N values. RESULTS Less than half of the pasture changes were linked with a significant isotopic shift while numerous isotopic shifts did not correspond to any altitudinal mobility. Similar patterns of δ13 C and δ15 N variations were observed between the different horses, despite differences in mobility patterns. We propose that water availability as well as seasonal availability of N2 fixing type plants primarily controlled horse hair δ13 C and δ15 N values, overprinting the influence of altitude. CONCLUSIONS Our study shows that altitudinal mobility is not the main factor that drives the variations in horse tail hair δ13 C and δ15 N values and that seasonal change in the animal dietary preference also plays an important role. It is therefore risky to interpret variations in δ13 C and δ15 N values of animal tissues in terms of altitudinal mobility alone, at least in C3 -dominated environments.
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Affiliation(s)
- Nicolas Lazzerini
- Archéozoologie, Archéobotanique: sociétés, pratiques et environnements (UMR 7209 AASPE), CNRS, Muséum national d'Histoire naturelle, CP56, 55 rue Buffon, 75005, Paris, France
| | - Aurélie Coulon
- Centre d'Ecologie et des Sciences de la Conservation (UMR 7204 CESCO), CNRS, Muséum national d'Histoire naturelle, CP135, 57 rue Cuvier, 75005, Paris, France
- CEFE, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Laurent Simon
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR 5023 LEHNA, 69622, Villeurbanne, France
| | - Charlotte Marchina
- Institut Français de Recherche sur l'Asie de l'Est (IFRAE), FRE 2025, Inalco/Université de Paris/CNRS, 2 rue de Lille, 75007, Paris, France
| | - Bayarkhuu Noost
- Mongolian Academy of Sciences, Institute of History and Archaeology, Mongolia
| | - Sébastien Lepetz
- Archéozoologie, Archéobotanique: sociétés, pratiques et environnements (UMR 7209 AASPE), CNRS, Muséum national d'Histoire naturelle, CP56, 55 rue Buffon, 75005, Paris, France
| | - Antoine Zazzo
- Archéozoologie, Archéobotanique: sociétés, pratiques et environnements (UMR 7209 AASPE), CNRS, Muséum national d'Histoire naturelle, CP56, 55 rue Buffon, 75005, Paris, France
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Cullen TM, Longstaffe FJ, Wortmann UG, Goodwin MB, Huang L, Evans DC. Stable isotopic characterization of a coastal floodplain forest community: a case study for isotopic reconstruction of Mesozoic vertebrate assemblages. ROYAL SOCIETY OPEN SCIENCE 2019; 6:181210. [PMID: 30891263 PMCID: PMC6408390 DOI: 10.1098/rsos.181210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 01/04/2019] [Indexed: 06/09/2023]
Abstract
Stable isotopes are powerful tools for elucidating ecological trends in extant vertebrate communities, though their application to Mesozoic ecosystems is complicated by a lack of extant isotope data from comparable environments/ecosystems (e.g. coastal floodplain forest environments, lacking significant C4 plant components). We sampled 20 taxa across a broad phylogenetic, body size, and physiological scope from the Atchafalaya River Basin of Louisiana as an environmental analogue to the Late Cretaceous coastal floodplains of North America. Samples were analysed for stable carbon, oxygen and nitrogen isotope compositions from bioapatite and keratin tissues to test the degree of ecological resolution that can be determined in a system with similar environmental conditions, and using similar constraints, as those in many Mesozoic assemblages. Isotopic results suggest a broad overlap in resource use among taxa and considerable terrestrial-aquatic interchange, highlighting the challenges of ecological interpretation in C3 systems, particularly when lacking observational data for comparison. We also propose a modified oxygen isotope-temperature equation that uses mean endotherm and mean ectotherm isotope data to more precisely predict temperature when compared with measured Atchafalaya River water data. These results provide a critical isotopic baseline for coastal floodplain forests, and act as a framework for future studies of Mesozoic palaeoecology.
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Affiliation(s)
- T. M. Cullen
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, CanadaM5S 3B2
- Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, CanadaM5S 2C6
| | - F. J. Longstaffe
- Department of Earth Sciences, The University of Western Ontario, 1151 Richmond Street, London, Ontario, CanadaN6A 5B7
| | - U. G. Wortmann
- Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, Ontario, CanadaM5S 3B1
| | - M. B. Goodwin
- University of California Museum of Paleontology, 1101 Valley Life Sciences, Berkeley, CA 94720-4780, USA
| | - L. Huang
- Department of Earth Sciences, The University of Western Ontario, 1151 Richmond Street, London, Ontario, CanadaN6A 5B7
| | - D. C. Evans
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, CanadaM5S 3B2
- Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, CanadaM5S 2C6
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Wessling EG, Oelze VM, Eshuis H, Pruetz JD, Kühl HS. Stable isotope variation in savanna chimpanzees (Pan troglodytes verus) indicate avoidance of energetic challenges through dietary compensation at the limits of the range. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 168:665-675. [PMID: 30693959 DOI: 10.1002/ajpa.23782] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 12/20/2018] [Accepted: 01/02/2019] [Indexed: 11/08/2022]
Abstract
OBJECTIVES Food scarcity is proposed to be a limitation to chimpanzees at the limits of their range; however, such a constraint has never been investigated in this context. We investigated patterns of δ13 C and δ15 N variation along a latitudinal gradient at the northwestern West African chimpanzee (Pan troglodytes verus) range limit with the expectation that isotope ratios of chimpanzees at the range limit will indicate different dietary strategies or higher physiological constraints than chimpanzees further from the edge. MATERIALS AND METHODS We measured δ13 C and δ15 N values in hair (n = 81) and plant food (n = 342) samples from five chimpanzee communities located along a latitudinal gradient in Southeastern Senegal. RESULTS We found clear grouping patterns in hair δ13 C and δ15 N in the four southern sites compared to the northernmost site. Environmental baseline samples collected from these sites revealed overall higher plant δ15 N values at the northernmost site, but similar δ13 C values across sites. By accounting for environmental baseline, Δ13 C and Δ15 N values were clustered for all five sites relative to total Pan variation, but indicated a 13 C-enriched diet at the range limit. DISCUSSION Clustering in Δ13 C and Δ15 N values supports that strategic shifting between preferred and fallback foods is a likely ubiquitous but necessary strategy employed by these chimpanzees to cope with their environment, potentially allowing chimpanzees at their limits to avoid periods of starvation. These results also underline the necessity of accounting for local isotopic baseline differences during inter-site comparison.
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Affiliation(s)
- Erin G Wessling
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,German Centre for Integrative Biodiversity Research (iDiv), Leipzig, Germany
| | - Vicky M Oelze
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Department of Anthropology, University of California Santa Cruz, Santa Cruz, California
| | - Henk Eshuis
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Jill D Pruetz
- Department of Anthropology, Texas State University, San Marcos, Texas
| | - Hjalmar S Kühl
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,German Centre for Integrative Biodiversity Research (iDiv), Leipzig, Germany
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5
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Stable isotope ecology of black rhinos (Diceros bicornis) in Kenya. Oecologia 2018; 187:1095-1105. [DOI: 10.1007/s00442-018-4185-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 06/05/2018] [Indexed: 10/28/2022]
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Monahan FJ, Schmidt O, Moloney AP. Meat provenance: Authentication of geographical origin and dietary background of meat. Meat Sci 2018; 144:2-14. [PMID: 29859716 DOI: 10.1016/j.meatsci.2018.05.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/10/2018] [Indexed: 02/07/2023]
Abstract
The authenticity of meat is now an important consideration in the multi-step food chain from production of animals on farm to consumer consumption of the final meat product. A range of techniques, involving analysis of elemental and molecular constituents of meat, fingerprint profiling and multivariate statistical analysis exists and these techniques are evolving in the quest to provide robust methods of establishing the dietary background of animals and the geographical origin of the meat derived from them. The potential application to meat authentication of techniques such as stable isotope ratio analysis applied to different animal tissues, measurement in meat of compounds directly derived from the diet of animals, such as fatty acids and fat soluble vitamins, and spectroscopy is explored. Challenges pertaining to the interpretation of data, as they relate to assignment of dietary background or geographical origin, are discussed.
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Affiliation(s)
- Frank J Monahan
- University College Dublin, School of Agriculture and Food Science, Dublin 4, Ireland.
| | - Olaf Schmidt
- University College Dublin, School of Agriculture and Food Science, Dublin 4, Ireland.
| | - Aidan P Moloney
- Teagasc, Animal & Grassland Research and Innovation Centre, Grange, Co. Meath, Ireland.
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Hammes V, Nüsse O, Isselstein J, Kayser M. Using 13C in cattle hair to trace back the maize level in the feeding regime-A field test. PLoS One 2017; 12:e0188926. [PMID: 29182681 PMCID: PMC5705144 DOI: 10.1371/journal.pone.0188926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 11/15/2017] [Indexed: 11/19/2022] Open
Abstract
Sections from cattle hair serve as an isotopic archive-they contain information on the cattle diet from different time periods. We tested the reliability of 13C signatures (δ13C) in cattle tail switch hair to retrospectively trace back the annual dietary proportion of maize of different production systems without having to sample and analyze the feed. Furthermore, we investigated if differences in dietary proportion of maize during summer and winter feeding can be detected in a single tail switch hair by sampling hair only once a year. We sampled hair and obtained information on management and annual composition of diets on 23 cattle farms in northern Germany. Farms differed in dietary proportions of maize, grass and concentrates as well as in grazing regime (year-round grazing, summer grazing, no grazing). We found that the annual mean δ13C values (δ13CY) of two hair sections that contain the isotopic information of summer and winter feeding is a robust indicator for the annual proportion of maize in cattle diet on a farm. The grazing regimes could clearly be distinguished by analyzing seasonal mean δ13C values (δ13CS). We could also demonstrate short term changes in the diet changes by means of δ13CS. We conclude that the method can be used in different cattle production systems to check on dietary proportions of maize for a period of one year before sampling of hair.
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Affiliation(s)
- Verena Hammes
- Georg-August-University of Goettingen, Department of Crop Sciences, Grassland Science, Location Vechta, Vechta, Germany
- * E-mail:
| | - Olaf Nüsse
- Georg-August-University of Goettingen, Department of Crop Sciences, Grassland Science, Location Vechta, Vechta, Germany
| | - Johannes Isselstein
- Georg-August-University of Goettingen, Department of Crop Sciences, Grassland Science, Goettingen, Germany
- Georg-August-University of Goettingen, Centre of Biodiversity and Sustainable Land Use, Goettingen, Germany
| | - Manfred Kayser
- Georg-August-University of Goettingen, Department of Crop Sciences, Grassland Science, Location Vechta, Vechta, Germany
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8
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Hoof Growth Rates of the European Roe Deer (Capreolus capreolus) for Dating the Hoof’s Isotopic Archive. FORESTS 2017. [DOI: 10.3390/f8120462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Isotopic ratio analysis of cattle tail hair: A potential tool in building the database for cow milk geographical traceability. Food Chem 2017; 217:438-444. [DOI: 10.1016/j.foodchem.2016.08.130] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 11/17/2022]
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von Holstein ICC, Makarewicz CA. Geographical variability in northern European sheep wool isotopic composition (δ(13) C, δ(15) N, δ(2) H values). RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:1423-1434. [PMID: 27197035 DOI: 10.1002/rcm.7578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/31/2016] [Accepted: 04/02/2016] [Indexed: 06/05/2023]
Abstract
RATIONALE Light stable isotopic analysis of herbivore proteinaceous tissues (hair, muscle, milk) is critical for authenticating the point of origin of finished agricultural or industrial products in both ancient and modern economies. This study examined the distribution of light stable isotopes in herbivores in northern Europe (Iceland to Finland), which is expected to depend on regional-level environmental inputs (precipitation, temperature) and local variables (vegetation type, fodder type, soil type). METHODS Sheep wool was obtained from animals managed using traditional methods and located across a gradient of northern European environments. Defatted whole-year samples were analysed by isotope ratio mass spectrometry (IRMS) for carbon (δ(13) C values), nitrogen (δ(15) N values) and un-exchangeable hydrogen (δ(2) H values) isotopic composition. RESULTS Wool δ(13) C, δ(15) N and δ(2) H values showed the same correlations to local mean annual precipitation and temperature as were expected for graze plants. Wool δ(2) H values were correlated with local modelled meteoric water δ(2) H values, mediated by plant solid tissue and leaf water fractionations. Cluster analysis distinguished wool from Sweden and the Baltic region from more western material. Local variation in vegetation or soil type did not disrupt dependence on climatic variables but did affect geospatial discrimination. CONCLUSIONS Wool isotopic composition in northern Europe is controlled by the effects of local precipitation and temperature on graze plant inputs, and is only weakly affected by pasture type. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
| | - Cheryl A Makarewicz
- Institut für Ur- und Frühgeschichte, Christian-Albrechts-Universität, D-24098, Kiel, Germany
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Auerswald K, Schäufele R, Bellof G. Routing of Fatty Acids from Fresh Grass to Milk Restricts the Validation of Feeding Information Obtained by Measuring (13)C in Milk. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:10500-10507. [PMID: 26567466 DOI: 10.1021/acs.jafc.5b03646] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Dairy production systems vary widely in their feeding and livestock-keeping regimens. Both are well-known to affect milk quality and consumer perceptions. Stable isotope analysis has been suggested as an easy-to-apply tool to validate a claimed feeding regimen. Although it is unambiguous that feeding influences the carbon isotope composition (δ(13)C) in milk, it is not clear whether a reported feeding regimen can be verified by measuring δ(13)C in milk without sampling and analyzing the feed. We obtained 671 milk samples from 40 farms distributed over Central Europe to measure δ(13)C and fatty acid composition. Feeding protocols by the farmers in combination with a model based on δ(13)C feed values from the literature were used to predict δ(13)C in feed and subsequently in milk. The model considered dietary contributions of C3 and C4 plants, contribution of concentrates, altitude, seasonal variation in (12/13)CO2, Suess's effect, and diet-milk discrimination. Predicted and measured δ(13)C in milk correlated closely (r(2) = 0.93). Analyzing milk for δ(13)C allowed validation of a reported C4 component with an error of <8% in 95% of all cases. This included the error of the method (measurement and prediction) and the error of the feeding information. However, the error was not random but varied seasonally and correlated with the seasonal variation in long-chain fatty acids. This indicated a bypass of long-chain fatty acids from fresh grass to milk.
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Affiliation(s)
- Karl Auerswald
- Lehrstuhl für Grünlandlehre, Technische Universität München , D-85350 Freising, Germany
| | - Rudi Schäufele
- Lehrstuhl für Grünlandlehre, Technische Universität München , D-85350 Freising, Germany
| | - Gerhard Bellof
- Fachgebiet Tierernährung, Hochschule Weihenstephan-Triesdorf , D-85350 Freising, Germany
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Pietersen DW, Symes CT, Woodborne S, McKechnie AE, Jansen R. Diet and prey selectivity of the specialist myrmecophage, Temminck's ground pangolin. J Zool (1987) 2015. [DOI: 10.1111/jzo.12302] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- D. W. Pietersen
- Mammal Research Institute; Department of Zoology and Entomology; University of Pretoria; Hatfield South Africa
- African Pangolin Working Group; Pretoria South Africa
| | - C. T. Symes
- School of Animal, Plant and Environmental Sciences; University of the Witwatersrand; Johannesburg South Africa
| | - S. Woodborne
- Mammal Research Institute; Department of Zoology and Entomology; University of Pretoria; Hatfield South Africa
- iThemba LABS; Johannesburg South Africa
| | - A. E. McKechnie
- Mammal Research Institute; Department of Zoology and Entomology; University of Pretoria; Hatfield South Africa
| | - R. Jansen
- African Pangolin Working Group; Pretoria South Africa
- Department of Environmental; Water and Earth Sciences; Tshwane University of Technology; Pretoria South Africa
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Zazzo A, Cerling TE, Ehleringer JR, Moloney AP, Monahan FJ, Schmidt O. Isotopic composition of sheep wool records seasonality of climate and diet. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:1357-1369. [PMID: 26147475 DOI: 10.1002/rcm.7228] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 05/11/2015] [Accepted: 05/11/2015] [Indexed: 06/04/2023]
Abstract
RATIONALE Hair keratin is a very important material in ecological and archaeological studies because it grows continuously, can be obtained non-invasively, does not require extensive processing prior to analysis and can be found in archaeological sites. Only a few studies have examined seasonal variations in hair isotope values, and there is no published dataset examining the isotope variability recorded in the keratinous tissues of stationary (i.e., non-migrating) domestic mammals. METHODS Thirty-six Irish sheep were sampled in eight farms every three months between September 2006 and June 2007. A shearing strategy was adopted to sample only the most recently grown wool in order to represent an average of the summer, autumn, winter and spring conditions. The stable isotope ratios of the ground samples were measured using two different stable isotope mass spectrometers operated in dual-inlet (C, N) and continuous-flow (O, H) mode. RESULTS Wool O isotope ratios are a good proxy for seasonal variability in climate and can be used to anchor a chronology independently of other isotope records (C, N) that are influenced by diet or physiology. By contrast, interpretation of seasonal variations in hair H isotope composition in terms of climate is more complex probably due to the influence of dietary H. The C and N isotope values of grass-fed animals varied seasonally, probably reflecting the annual cycle of seasonal variation in grass isotope values. The highest δ(13) C values were measured in summer-grown wool, while the highest δ(15) N values were measured in winter-grown wool. Supplementation of the sheep diet with concentrates was detected easily and was marked by an increase in δ(13) C values and a decrease in δ(15) N values in winter-grown wool. CONCLUSIONS The present study demonstrates that time-resolved sampling and stable isotope ratio analysis of sheep wool can be used to identify short-term changes in diet and climate and therefore offer a tool to examine a wide variety of present and past husbandry practices.
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Affiliation(s)
- A Zazzo
- CNRS UMR 7209, Muséum National d'Histoire Naturelle, "Archéozoologie, Archéobotanique: Sociétés, Pratiques et Environnements", Département "Ecologie et Gestion de la Biodiversité", CP 56, 55 rue Buffon, F-75005, Paris, France
| | - T E Cerling
- Department of Geology and Geophysics, Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| | - J R Ehleringer
- Global Change and Sustainability Center and Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| | - A P Moloney
- Teagasc, Animal and Grassland Research and Innovation Centre, Dunsany, Co. Meath, Ireland
| | - F J Monahan
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - O Schmidt
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland
- UCD Earth Institute, University College Dublin, Belfield, Dublin 4, Ireland
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Holá M, Ježek M, Kušta T, Košatová M. Trophic discrimination factors of stable carbon and nitrogen isotopes in hair of corn fed wild boar. PLoS One 2015; 10:e0125042. [PMID: 25915400 PMCID: PMC4411150 DOI: 10.1371/journal.pone.0125042] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 03/09/2015] [Indexed: 11/24/2022] Open
Abstract
Stable isotope measurements are increasingly being used to gain insights into the nutritional ecology of many wildlife species and their role in ecosystem structure and function. Such studies require estimations of trophic discrimination factors (i.e. differences in the isotopic ratio between the consumer and its diet). Although trophic discrimination factors are tissue- and species- specific, researchers often rely on generalized, and fixed trophic discrimination factors that have not been experimentally derived. In this experimental study, captive wild boar (Sus scrofa) were fed a controlled diet of corn (Zea mays), a popular and increasingly dominant food source for wild boar in the Czech Republic and elsewhere in Europe, and trophic discrimination factors for stable carbon (Δ13C) and nitrogen (Δ15N) isotopes were determined from hair samples. The mean Δ13C and Δ15N in wild boar hair were –2.3 ‰ and +3.5 ‰, respectively. Also, in order to facilitate future derivations of isotopic measurements along wild boar hair, we calculated the average hair growth rate to be 1.1 mm d-1. Our results serve as a baseline for interpreting isotopic patterns of free-ranging wild boar in current European agricultural landscapes. However, future research is needed in order to provide a broader understanding of the processes underlying the variation in trophic discrimination factors of carbon and nitrogen across of variety of diet types.
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Affiliation(s)
- Michaela Holá
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
- * E-mail:
| | - Miloš Ježek
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Tomáš Kušta
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Michaela Košatová
- Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
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Inácio CT, Chalk PM. Principles and limitations of stable isotopes in differentiating organic and conventional foodstuffs: 2. Animal products. Crit Rev Food Sci Nutr 2015; 57:181-196. [DOI: 10.1080/10408398.2014.887056] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Bahar B, Harrison SM, Moloney AP, Monahan FJ, Schmidt O. Isotopic turnover of carbon and nitrogen in bovine blood fractions and inner organs. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:1011-1018. [PMID: 24677522 DOI: 10.1002/rcm.6872] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 02/14/2014] [Accepted: 02/15/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Isotope ratio analysis of bovine tissues is a tool for inferring aspects of the dietary history of cattle. The objective of this experiment was to quantify the carbon (C) and nitrogen (N) isotopic turnover in blood (serum and residue) and inner organs (liver, kidney, heart and brain) of beef cattle. METHODS Growing beef cattle (n = 70 in total) were either switched from a control diet containing barley and urea to an experimental diet containing maize and (15)N-enriched urea, for various intervals prior to slaughter or maintained on the control diet for 168 days pre-slaughter. Samples of blood, liver, kidney, heart and brain were collected at 0, 14, 28, 56, 112 and 168 days and analysed using Isotope Ratio Mass Spectrometry. RESULTS After 168 days, C- and N-isotopic equilibrium was reached in the blood serum, liver and kidney, approached in the heart and brain, but not reached in the non-serum component of blood. The estimated C and N half-lives were 16.5 and 20.7 days for liver, 19.2 and 25.5 days for kidney, 29.2 and 35.6 days for blood serum, 37.6 and 49.9 days for heart, 53.3 and 52.2 days for brain and 113.3 and 115.0 days for the non-serum blood residue, respectively. Modelling the C and N turnover in the different tissue combinations revealed that a combined analysis of liver and heart as well as brain and kidney can provide the most accurate estimation of the timing of the diet switch. CONCLUSIONS Based on the difference in turnover rates, bovine soft tissues can provide isotopic information on short- and long-term dietary changes, which in turn may be linked to the geographic or production origin of beef cattle. This study also provides basic biological data on organ C and N turnover in a large herbivorous mammal.
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Affiliation(s)
- Bojlul Bahar
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland
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17
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Macharia AN, Cerling TE, Jorgensen MJ, Kaplan JR. The Hair-Diet13C and15N Fractionation inChlorocebus aethiops sabaeusBased on a Control Diet Study. ANN ZOOL FENN 2014. [DOI: 10.5735/086.051.0208] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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18
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Medieval horse stable; the results of multi proxy interdisciplinary research. PLoS One 2014; 9:e89273. [PMID: 24670874 PMCID: PMC3966733 DOI: 10.1371/journal.pone.0089273] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 01/17/2014] [Indexed: 11/19/2022] Open
Abstract
A multi proxy approach was applied in the reconstruction of the architecture of Medieval horse stable architecture, the maintenance practices associated with that structure as well as horse alimentation at the beginning of 13th century in Central Europe. Finally, an interpretation of the local vegetation structure along Morava River, Czech Republic is presented. The investigated stable experienced two construction phases. The infill was well preserved and its composition reflects maintenance practices. The uppermost part of the infill was composed of fresh stabling, which accumulated within a few months at the end of summer. Horses from different backgrounds were kept in the stable and this is reflected in the results of isotope analyses. Horses were fed meadow grasses as well as woody vegetation, millet, oat, and less commonly hemp, wheat and rye. Three possible explanations of stable usage are suggested. The stable was probably used on a temporary basis for horses of workers employed at the castle, courier horses and horses used in battle.
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Braun A, Schneider S, Auerswald K, Bellof G, Schnyder H. Forward modeling of fluctuating dietary 13C signals to validate 13C turnover models of milk and milk components from a diet-switch experiment. PLoS One 2014; 8:e85235. [PMID: 24392000 PMCID: PMC3877384 DOI: 10.1371/journal.pone.0085235] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Accepted: 12/01/2013] [Indexed: 12/05/2022] Open
Abstract
Isotopic variation of food stuffs propagates through trophic systems. But, this variation is dampened in each trophic step, due to buffering effects of metabolic and storage pools. Thus, understanding of isotopic variation in trophic systems requires knowledge of isotopic turnover. In animals, turnover is usually quantified in diet-switch experiments in controlled conditions. Such experiments usually involve changes in diet chemical composition, which may affect turnover. Furthermore, it is uncertain if diet-switch based turnover models are applicable under conditions with randomly fluctuating dietary input signals. Here, we investigate if turnover information derived from diet-switch experiments with dairy cows can predict the isotopic composition of metabolic products (milk, milk components and feces) under natural fluctuations of dietary isotope and chemical composition. First, a diet-switch from a C3-grass/maize diet to a pure C3-grass diet was used to quantify carbon turnover in whole milk, lactose, casein, milk fat and feces. Data were analyzed with a compartmental mixed effects model, which allowed for multiple pools and intra-population variability, and included a delay between feed ingestion and first tracer appearance in outputs. The delay for milk components and whole milk was ∼12 h, and that of feces ∼20 h. The half-life (t½) for carbon in the feces was 9 h, while lactose, casein and milk fat had a t½ of 10, 18 and 19 h. The 13C kinetics of whole milk revealed two pools, a fast pool with a t½ of 10 h (likely representing lactose), and a slower pool with a t½ of 21 h (likely including casein and milk fat). The diet-switch based turnover information provided a precise prediction (RMSE ∼0.2 ‰) of the natural 13C fluctuations in outputs during a 30 days-long period when cows ingested a pure C3 grass with naturally fluctuating isotope composition.
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Affiliation(s)
- Alexander Braun
- Lehrstuhl für Grünlandlehre, Department of Plant Science, Technische Universität München, Freising, Germany
| | - Stephan Schneider
- Fachgebiet Tierernährung, Fakultät Land- und Ernährungswirtschaft, Hochschule Weihenstephan-Triesdorf, Freising, Germany
| | - Karl Auerswald
- Lehrstuhl für Grünlandlehre, Department of Plant Science, Technische Universität München, Freising, Germany
- * E-mail:
| | - Gerhard Bellof
- Fachgebiet Tierernährung, Fakultät Land- und Ernährungswirtschaft, Hochschule Weihenstephan-Triesdorf, Freising, Germany
| | - Hans Schnyder
- Lehrstuhl für Grünlandlehre, Department of Plant Science, Technische Universität München, Freising, Germany
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20
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Monahan F, Moloney A, Osorio M, Röhrle F, Schmidt O, Brennan L. Authentication of grass-fed beef using bovine muscle, hair or urine. Trends Food Sci Technol 2012. [DOI: 10.1016/j.tifs.2012.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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21
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Yanagi Y, Hirooka H, Oishi K, Choumei Y, Hata H, Arai M, Kitagawa M, Gotoh T, Inada S, Kumagai H. Stable carbon and nitrogen isotope analysis as a tool for inferring beef cattle feeding systems in Japan. Food Chem 2012. [DOI: 10.1016/j.foodchem.2012.02.107] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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22
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Auerswald K, Rossmann A, Schäufele R, Schwertl M, Monahan FJ, Schnyder H. Does natural weathering change the stable isotope composition (²H, ¹³C, ¹⁵N, ¹⁸O and ³⁴S) of cattle hair? RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:3741-3748. [PMID: 22468330 DOI: 10.1002/rcm.5284] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Stable isotope analysis of hair has found applications in many fields of science because it provides a temporally resolved, fairly stable isotopic archive of mammalian individuals. We investigated whether this hair archive is modified by natural weathering while attached to a living animal. We analyzed the tail switch hairs of one suckler cow, sampled seven times over a period of four annual summer pasture-winter stall feeding cycles. We compared relative isotope ratios (δ²H, δ¹³C, δ¹⁵N, δ¹⁸O and δ³⁴S) of sections of hair that grew simultaneously but were exposed to natural weathering conditions over different periods of time. Natural wear caused a loss of mass of approx. 0.13% day⁻¹, with no apparent effect of environmental conditions. Changes in δ²H, δ¹³C, δ¹⁵N and δ¹⁸O were below the detection limit, indicating that hair is a reliable archive for the isotopes of these elements. In contrast, δ³⁴S values increased during the grazing period by about 1‰, with exposure to UV radiation appearing to have a major influence on this result. The δ³⁴S values decreased during the subsequent stall period, probably due to abrasion. Seasonal variation in δ³⁴S may indicate alternating environments that differ in their weathering conditions.
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Affiliation(s)
- Karl Auerswald
- Lehrstuhl für Grünlandlehre, Technische Universität München, Freising-Weihenstephan, Germany.
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Osorio MT, Moloney AP, Schmidt O, Monahan FJ. Beef authentication and retrospective dietary verification using stable isotope ratio analysis of bovine muscle and tail hair. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:3295-3305. [PMID: 21391592 DOI: 10.1021/jf1040959] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Stable isotope ratio analysis (SIRA) was used as an analytical tool to verify the preslaughter diet of beef cattle. Muscle and tail hair samples were collected from animals fed either pasture (P), a barley-based concentrate (C), silage followed by pasture (SiP), or silage followed by pasture with concentrate (SiPC) for 1 year (n = 25 animals per treatment). The (13)C/(12)C, (15)N/(14)N, (2)H/(1)H, and (34)S/(32)S isotope ratios in muscle clearly reflected those of the diets consumed by the animals. By applying a stepwise canonical discriminant analysis, a good discrimination of bovine meat according to dietary regimen was obtained. On the basis of the classification success rate, the (13)C/(12)C and (34)S/(32)S ratios in muscle were the best indicators for authentication of beef from animals consuming the different diets. Analysis of (13)C/(12)C and (15)N/(14)N in tail hair sections provided an archival record of changes to the diet of the cattle for periods of over 1 year preslaughter.
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Affiliation(s)
- M Teresa Osorio
- School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
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24
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Tiunov AV, Kirillova IV. Stable isotope ((13)C/(12)C and (15)N/(14)N) composition of the woolly rhinoceros Coelodonta antiquitatis horn suggests seasonal changes in the diet. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2010; 24:3146-3150. [PMID: 20941761 DOI: 10.1002/rcm.4755] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The extinct woolly rhinoceros Coelodonta antiquitatis is a prominent member of the Mammuthus-Coelodonta faunal complex, but its biology is poorly known, partly because very few specimens with well-preserved soft tissues have been discovered to date. However, the permafrost-preserved horns of the woolly rhinoceros are recording structures which contain isotopic records of the diet, environmental conditions and physiological status of the animal during most of its life. In this study we report the first data on the pattern of carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) isotopic composition along the nasal horn of woolly rhinoceros. We found systematic variations in δ(13)C and δ(15)N values associated with morphologically expressed transverse banding of the horn. The comparative analysis of isotopic variation in keratinous tissues of extant and extinct herbivores suggests that the oscillation in isotopic composition of the horn was induced by seasonal changes in the diet. Although the compiled evidence is in part contradictory, we suggest that more positive δ(13)C and δ(15)N values associated with dark-colored and less dense zones of the horn indicate a summer diet. More dense and light-colored zones of the horn have lower δ(13)C and δ(15)N values possibly indicating a larger proportion of woody and shrub vegetation in the winter diet. The validity of these conclusions has to be proven in further investigations, but our data underline the potential of isotopic analysis for studies on diet and habitat use by extinct members of Pleistocene fauna.
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Affiliation(s)
- Alexei V Tiunov
- Institute of Ecology and Evolution RAS, Leninsky Prospect 33, Moscow 119071, Russia.
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Auerswald K, Wittmer MHOM, Zazzo A, Schäufele R, Schnyder H. Biases in the analysis of stable isotope discrimination in food webs. J Appl Ecol 2010. [DOI: 10.1111/j.1365-2664.2009.01764.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Sponheimer M, Codron D, Passey BH, de Ruiter DJ, Cerling TE, Lee-Thorp JA. Using carbon isotopes to track dietary change in modern, historical, and ancient primates. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2010; 140:661-70. [PMID: 19890855 DOI: 10.1002/ajpa.21111] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Stable isotope analysis can be used to document dietary changes within the lifetimes of individuals and may prove useful for investigating fallback food consumption in modern, historical, and ancient primates. Feces, hair, and enamel are all suitable materials for such analysis, and each has its own benefits and limitations. Feces provide highly resolved temporal dietary data, but are generally limited to providing dietary information about modern individuals and require labor-intensive sample collection and analysis. Hair provides less well-resolved data, but has the advantage that one or a few hair strands can provide evidence of dietary change over months or years. Hair is also available in museum collections, making it possible to investigate the diets of historical specimens. Enamel provides the poorest temporal resolution of these materials, but is often preserved for millions of years, allowing examination of dietary change in deep time. We briefly discuss the use of carbon isotope data as it pertains to recent thinking about fallback food consumption in ancient hominins and suggest that we may need to rethink the functional significance of the australopith masticatory package.
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Affiliation(s)
- Matt Sponheimer
- Department of Anthropology, University of Colorado at Boulder, Boulder, CO 80309, USA.
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27
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Drucker DG, Hobson KA, Ouellet JP, Courtois R. Influence of forage preferences and habitat use on 13C and 15N abundance in wild caribou (Rangifer tarandus caribou) and moose (Alces alces) from Canada. ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES 2010; 46:107-121. [PMID: 20229388 DOI: 10.1080/10256010903388410] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Stable isotope composition (delta(13)C and delta(15)N) of moose (Alces alces) and caribou (Rangifer tarandus) hair from the boreal forest of Jacques-Cartier Park and Cote-Nord (Quebec) and arctic tundra of Queen Maud Gulf and Southampton Island (Nunavut) was investigated as an indicator of dietary preferences and habitat use. Values of delta(13)C(hair) and delta(15)N(hair) in moose were consistently lower compared to those of caribou. This is consistent with the depletion in (13)C and (15)N in the plants preferred by moose, essentially browse (shrub and tree leaves), compared to caribou forage, which included significant amounts of graminoids, lichen and fungi. The delta(13)C(hair) values of caribou differed between closed boreal forest and open-tundra ecosystems. This pattern followed that expected from the canopy effect observed in plant communities. Variation in delta(15)N(hair) values of caribou was probably linked to the effect of different climatic conditions on plant communities. This study underlines the potential of isotopic analysis for studies on diet and habitat selection within a pure C(3) plant environment.
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28
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Bahar B, Moloney AP, Monahan FJ, Harrison SM, Zazzo A, Scrimgeour CM, Begley IS, Schmidt O. Turnover of carbon, nitrogen, and sulfur in bovine longissimus dorsi and psoas major muscles: Implications for isotopic authentication of meat1. J Anim Sci 2009; 87:905-13. [PMID: 19066249 DOI: 10.2527/jas.2008-1360] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- B Bahar
- UCD School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
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29
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Zazzo A, Moloney AP, Monahan FJ, Scrimgeour CM, Schmidt O. Effect of age and food intake on dietary carbon turnover recorded in sheep wool. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:2937-2945. [PMID: 18727150 DOI: 10.1002/rcm.3693] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We present the results of a series of controlled feeding experiments with sheep, designed to investigate the effects of age and level of food intake on the kinetics of incorporation of the dietary carbon signal into wool. Four different groups of three sheep each, ranging in age from 6 to 78 months, were fed a C(3) diet and switched to a C(4) diet for up to 250 days. Different quantities of the same C(4) diet were provided to each group, in order to achieve different growth rates (high, low, and no growth). Wool was repeatedly shorn from each animal and processed for delta(13)C analyses. Results show that newly grown wool does not start recording the isotope composition of the new diet immediately after the diet-switch. The time-lag varies according to the age of the animal, from 6 +/- 1 days in lambs to up to 15 +/- 4 days in the older ewes. Wool from fast-growing lambs approached equilibrium faster than that from slow-growing lambs and young ewes, with old ewes being the slowest. However, 3 weeks after the diet-switch, the differences in wool delta(13)C values between the four different groups of animals were relatively small and represented less than 15% of the isotopic difference between the two diets. These results suggest that a single equation can be used to reconstruct previous diets for animals of different age, provided that the diet is similar and all individuals are in positive protein balance.
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Affiliation(s)
- Antoine Zazzo
- Muséum national d'Histoire naturelle, Département Ecologie et Gestion de la Biodiversité, USM 303/UMR 5197-Laboratoire Archéozoologie, histoire des sociétés humaines et des peuplements animaux, 55 rue Buffon, Paris cedex 05, France.
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