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1.
Romain Amiot Xu Wang Shuo Wang Christophe Lécuyer Jean‐Michel Mazin Jinyou Mo Jean‐Pierre Flandrois François Fourel Xiaolin Wang Xing Xu Zhijun Zhang Zhonghe Zhou 《Palaeontology》2017,60(5):633-647
In order to determine the incubation temperature of eggs laid by non‐avian dinosaurs, we analysed the oxygen isotope compositions of both eggshell carbonate (δ18Oc) and embryo bone phosphate (δ18Op) from seven oviraptorosaur eggs with preserved in ovo embryo bones. These eggs come from the Upper Cretaceous Nanxiong Formation of Jiangxi Province, China. Oviraptorosaur theropods were selected because of their known brooding behaviour as evidenced by preserved adult specimens fossilized in brooding posture on their clutch. Incubation temperature of these embryos was estimated based on the following considerations: eggshell δ18Oc value reflects the oxygen isotope composition of egg water fluid; embryo bones precipitate from the same egg fluid; and oxygen isotope fractionation between phosphate and water is controlled by the egg temperature. A time‐dependent model predicting the δ18Op evolution of the embryo skeleton during incubation as a function of egg temperature was built, and measured δ18Oc and δ18Op values used as boundary conditions. According to the model outputs, oviraptorosaurs incubated their eggs within a 35–40°C range, similar to extant birds and compatible with the known active brooding behaviour of these theropod dinosaurs. Provided that both eggshell and embryo bones preserved their original oxygen isotope compositions, this method could be extended to investigate some reproductive traits of other extinct groups of oviparous amniotes. 相似文献
2.
BRENT R. HELLIKER 《Plant, cell & environment》2014,37(3):541-556
Using both oxygen isotope ratios of leaf water (δ18OL) and cellulose (δ18OC) of Tillandsia usneoides in situ, this paper examined how short‐ and long‐term responses to environmental variation and model parameterization affected the reconstruction of the atmospheric water vapour (δ18Oa). During sample‐intensive field campaigns, predictions of δ18OL matched observations well using a non‐steady‐state model, but the model required data‐rich parameterization. Predictions from the more easily parameterized maximum enrichment model (δ18OL–M) matched observed δ18OL and observed δ18Oa when leaf water turnover was less than 3.5 d. Using the δ18OL–M model and weekly samples of δ18OL across two growing seasons in Florida, USA, reconstructed δ18Oa was ?12.6 ± 0.3‰. This is compared with δ18Oa of ?12.4 ± 0.2‰ resolved from the growing‐season‐weighted δ18OC. Both of these values were similar to δ18Oa in equilibrium with precipitation, ?12.9‰. δ18Oa was also reconstructed through a large‐scale transect with δ18OL and the growing‐season‐integrated δ18OC across the southeastern United States. There was considerable large‐scale variation, but there was regional, weather‐induced coherence in δ18Oa when using δ18OL. The reconstruction of δ18Oa with δ18OC generally supported the assumption of δ18Oa being in equilibrium with precipitation δ18O (δ18Oppt), but the pool of δ18Oppt with which δ18Oa was in equilibrium – growing season versus annual δ18Oppt – changed with latitude. 相似文献
3.
Oxygen isotope fractionations across individual leaf carbohydrates in grass and tree species
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Marco M. Lehmann Bruno Gamarra Ansgar Kahmen Rolf T.W. Siegwolf Matthias Saurer 《Plant, cell & environment》2017,40(8):1658-1670
Almost no δ18O data are available for leaf carbohydrates, leaving a gap in the understanding of the δ18O relationship between leaf water and cellulose. We measured δ18O values of bulk leaf water (δ18OLW) and individual leaf carbohydrates (e.g. fructose, glucose and sucrose) in grass and tree species and δ18O of leaf cellulose in grasses. The grasses were grown under two relative humidity (rH) conditions. Sucrose was generally 18O‐enriched compared with hexoses across all species with an apparent biosynthetic fractionation factor (εbio) of more than 27‰ relative to δ18OLW, which might be explained by isotopic leaf water and sucrose synthesis gradients. δ18OLW and δ18O values of carbohydrates and cellulose in grasses were strongly related, indicating that the leaf water signal in carbohydrates was transferred to cellulose (εbio = 25.1‰). Interestingly, damping factor pexpx, which reflects oxygen isotope exchange with less enriched water during cellulose synthesis, responded to rH conditions if modelled from δ18OLW but not if modelled directly from δ18O of individual carbohydrates. We conclude that δ18OLW is not always a good substitute for δ18O of synthesis water due to isotopic leaf water gradients. Thus, compound‐specific δ18O analyses of individual carbohydrates are helpful to better constrain (post‐)photosynthetic isotope fractionation processes in plants. 相似文献
4.
Measurements of the carbon (δ13Cm) and oxygen (δ18Om) isotope composition of C3 plant tissue provide important insights into controls on water‐use efficiency. We investigated the causes of seasonal and inter‐annual variability in water‐use efficiency in a grassland near Lethbridge, Canada using stable isotope (leaf‐scale) and eddy covariance measurements (ecosystem‐scale). The positive relationship between δ13Cm and δ18Om values for samples collected during 1998–2001 indicated that variation in stomatal conductance and water stress‐induced changes in the degree of stomatal limitation of net photosynthesis were the major controls on variation in δ13Cm and biomass production during this time. By comparison, the lack of a significant relationship between δ13Cm and δ18Om values during 2002, 2003 and 2006 demonstrated that water stress was not a significant limitation on photosynthesis and biomass production in these years. Water‐use efficiency was higher in 2000 than 1999, consistent with expectations because of greater stomatal limitation of photosynthesis and lower leaf ci/ca during the drier conditions of 2000. Calculated values of leaf‐scale water‐use efficiency were 2–3 times higher than ecosystem‐scale water‐use efficiency, a difference that was likely due to carbon lost in root respiration and water lost during soil evaporation that was not accounted for by the stable isotope measurements. 相似文献
5.
Although considerable variation has been documented in tree‐ring cellulose oxygen isotope ratios (δ18Ocell) among co‐occurring species, the underlying causes are unknown. Here, we used a combination of field measurements and modelling to investigate the mechanisms behind variations in late‐wood δ18Ocell (δ18Olc) among three co‐occurring species (chestnut oak, black oak and pitch pine) in a temperate forest. For two growing seasons, we quantified among‐species variation in δ18Olc, as well as several variables that could potentially cause the δ18Olc variation. Data analysis based on the δ18Ocell model rules out leaf water enrichment (Δ18Olw) and tree‐ring formation period (Δt), but highlights source water δ18O (δ18Osw) as an important driver for the measured difference in δ18Olc between black and chestnut oak. However, the enriched δ18Olc in pitch pine relative to the oaks could not be sufficiently explained by consideration of the above three variables only, but rather, we show that differences in the proportion of oxygen exchange during cellulose synthesis (pex) is most likely a key mechanism. Our demonstration of the relevance of some species‐specific features (or lack thereof) to δ18Ocell has important implications for isotope based ecophysiological/paleoclimate studies. 相似文献
6.
Nitrogen fertilization and δ18O of CO2 have no effect on 18O‐enrichment of leaf water and cellulose in Cleistogenes squarrosa (C4) – is VPD the sole control?
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Hai Tao Liu Xiao Ying Gong Rudi Schäufele Fang Yang Regina Theresia Hirl Anja Schmidt Hans Schnyder 《Plant, cell & environment》2016,39(12):2701-2712
The oxygen isotope composition of cellulose (δ18OCel) archives hydrological and physiological information. Here, we assess previously unexplored direct and interactive effects of the δ18O of CO2 (δ18OCO2), nitrogen (N) fertilizer supply and vapour pressure deficit (VPD) on δ18OCel, 18O‐enrichment of leaf water (Δ18OLW) and cellulose (Δ18OCel) relative to source water, and pexpx, the proportion of oxygen in cellulose that exchanged with unenriched water at the site of cellulose synthesis, in a C4 grass (Cleistogenes squarrosa). δ18OCO2 and N supply, and their interactions with VPD, had no effect on δ18OCel, Δ18OLW, Δ18OCel and pexpx. Δ18OCel and Δ18OLW increased with VPD, while pexpx decreased. That VPD‐effect on pexpx was supported by sensitivity tests to variation of Δ18OLW and the equilibrium fractionation factor between carbonyl oxygen and water. N supply altered growth and morphological features, but not 18O relations; conversely, VPD had no effect on growth or morphology, but controlled 18O relations. The work implies that reconstructions of VPD from Δ18OCel would overestimate amplitudes of VPD variation, at least in this species, if the VPD‐effect on pexpx is ignored. Progress in understanding the relationship between Δ18OLW and Δ18OCel will require separate investigations of pex and px and of their responses to environmental conditions. 相似文献
7.
Jan Fischer Jörg W. Schneider John-Paul M. Hodnett David K. Elliott Gary D. Johnson Silke Voigt 《Historical Biology》2013,25(6):710-727
δ18OP values and 87Sr/86Sr ratios were determined on disarticulated xenacanthiform, hybodontid and ctenacanthid shark tooth material from several Early Permian (Sakmarian–Kungurian) continental bone beds of northern Texas and southern Oklahoma as well as from the marine Middle Permian (Roadian) of northern Arizona. The δ18OP values derived from the teeth of bone beds are in the range of 17.6–23.5‰ VSMOW, and are mostly depleted in 18O by 0.5–5‰ relative to proposed coeval marine δ18OP values. This indicates an adaptation to freshwater habitats on the Early Permian coastal plain by several sharks. Distinctly higher δ18OP values from two bone beds are attributed to significant evaporative enrichment in 18O in flood plain ponds. 87Sr/86Sr ratios of around 0.71077 are notably more radiogenic than 87Sr/86Sr of contemporaneous seawater. In contrast, the isotopic composition of teeth from the marine Kaibab Formation is characterised by low δ18OP values in the range of 13.4–15.6‰ VSMOW while 87Sr/86Sr ratios of around 0.70821 are closer to the Roadian seawater value. The distinctly depleted δ18OP values cannot be readily explained by fluvially affected freshening in a nearshore marine environment, so a diagenetic alteration of the Kaibab material seems to be more likely, excluding it from further interpretation. 相似文献
8.
KATHRIN STREIT ROLF T. W. SIEGWOLF FRANK HAGEDORN MARCUS SCHAUB NINA BUCHMANN 《Plant, cell & environment》2014,37(2):315-326
Alpine treelines are temperature‐limited vegetation boundaries. Understanding the effects of elevated [CO2] and warming on CO2 and H2O gas exchange may help predict responses of treelines to global change. We measured needle gas exchange of Larix decidua Mill. and Pinus mugo ssp. uncinata DC trees after 9 years of free air CO2 enrichment (575 µmol mol?1) and 4 years of soil warming (+4 °C) and analysed δ13C and δ18O values of needles and tree rings. Tree needles under elevated [CO2] showed neither nitrogen limitation nor end‐product inhibition, and no down‐regulation of maximal photosynthetic rate (Amax) was found. Both tree species showed increased net photosynthetic rates (An) under elevated [CO2] (L. decidua: +39%; P. mugo: +35%). Stomatal conductance (gH2O) was insensitive to changes in [CO2], thus transpiration rates remained unchanged and intrinsic water‐use efficiency (iWUE) increased due to higher An. Soil warming affected neither An nor gH2O. Unresponsiveness of gH2O to [CO2] and warming was confirmed by δ18O needle and tree ring values. Consequently, under sufficient water supply, elevated [CO2] induced sustained enhancement in An and lead to increased C inputs into this ecosystem, while soil warming hardly affected gas exchange of L. decidua and P. mugo at the alpine treeline. 相似文献
9.
Kyungcheol Choy Ok‐Ryun Jeon Benjamin T. Fuller Micheal P. Richards 《American journal of physical anthropology》2010,142(1):74-84
Stable carbon and nitrogen isotope analyses were conducted to investigate dietary variation in human skeletons (n = 109) from the Gaya cemetery at Yeanri located near Gimhae City, South Korea. The cemetery contained three distinct grave types dating to 4th–7th century AD. The main purposes of this research were to reconstruct palaeodiet in the Gaya population and to explore correlations between stable isotope compositions and burial types, inferred age, and sex of these individuals. The isotopic data indicate that the people at Yeanri consumed a predominantly C3‐based terrestrial diet supplemented with freshwater and/or marine resources. The comparison of isotopic results reveals significant differences in δ13C values among three adult burial types (wood‐cist coffin: ?18.5 ± 0.5‰, stone‐cist coffin: ?18.1 ± 0.6‰, mausoleum: ?17.8 ± 0.9‰). Males in wood‐cist and stone‐cist coffins have relatively more elevated mean δ13C and δ15N values than females. The isotopic ratios from the two adult age groups (21–40 years and 40–60 years) indicate that there was no significant dietary change in individuals with age. The isotope data from the infants and children suggest the weaning was a gradual process that was completed between 3 and 4 years of age in the Gaya population. This evidence indicates that the dietary variations within the cemetery reflect social status, sex, and childhood consumption patterns. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
10.
Bethany L. Turner Haagen D. Klaus Sarah V. Livengood Leslie E. Brown Fausto Saldaña Carlos Wester 《American journal of physical anthropology》2013,151(1):22-37
This study investigates two key variables—residential context and subsistence—among sacrificial victims dating to the Late Horizon (A.D. 1450–1532) in the Huaca de los Sacrificios at the Chotuna‐Chornancap Archaeological Complex in north coastal Peru. We investigate whether aspects of sacrifice in this distant coastal province mirrored that found in Inca heartland contexts such as the capacocha, or remained more typical of coastal sacrificial traditions. Stable carbon, nitrogen, and oxygen isotope values were characterized in bone carbonate, bone collagen, and hair keratin to estimate geographic residence during the decade before death and diet in the decade, versus months, before death. Bone δ18Ocarbonate values have a mean (±SD) of 26.8 ± 1.1%, bone δ13Ccarbonate values ?6.7 ± 1.7%, and bone δ13Ccollagen values 11.8 ± 1.3%; bone δ15Ncollagen values have a mean of 11.5 ± 1.3%. Combined hair δ13Ckeratin values have a mean of ?12.8 ± 1.6%, and hair δ15Nkeratin values 10.8 ± 1.3%. In contrast to contemporaneous coastal and highland contexts, we are unable to identify immigrants among the sacrificed individuals or changes in diet that indicate provisioning with a standardized diet leading up to death. Instead, results suggest that victims were local to the area, but consumed moderately variable diets consistent with local subsistence patterns. These findings suggest a distinct pattern of human sacrifice in the Late Horizon and underscore the regional and temporal variation in sacrificial practices in the central Andes. Am J Phys Anthropol 151:22–37, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
11.
Oxygen and carbon isotope compositions of middle Cretaceous vertebrates from North Africa and Brazil: Ecological and environmental significance 总被引:1,自引:0,他引:1
Romain Amiot Xu Wang Eric Buffetaut Lionel Cavin Frédéric Fluteau Haiyan Tong 《Palaeogeography, Palaeoclimatology, Palaeoecology》2010,297(2):439-451
In order to investigate mid-Cretaceous terrestrial climates of low paleolatitudes, Moroccan, Tunisian and Brazilian vertebrate apatites have been analyzed for their oxygen and carbon isotope compositions of phosphates (δ18Op) and carbonates (δ18Oc, δ13Cc). At each site, coexisting theropod dinosaurs, titanosaurid sauropods, pterosaurs, crocodilians, turtles and fish have distinct δ18Op and δ13Cc values reflecting their ecologies, diets and foraging environments. Oxygen isotope compositions of surface waters (δ18Ow) estimated from turtle and crocodile δ18Op values range from − 5.0 ± 1.0‰ to − 2.4 ± 1.0‰, which do not differ from mean annual rainwater values occurring today under inter-tropical sub-arid to arid climates. High water temperatures ranging from 21 ± 6 °C to 34 ± 2 °C deduced from fish δ18Op values are in agreement with those published for mid-Cretaceous low latitudes. Temporary or seasonal droughts are inferred from high δ18Op values of lungfish teeth, even though lower reptile δ18Op values suggest the use of distinct and most likely larger or regularly renewed bodies of water. Environmental conditions of the studied low latitude regions during the Aptian-Cenomanian interval were somewhat similar to those experienced today under semi-arid to arid tropical or equatorial climates, but with higher mean surface temperatures than present-day ones. 相似文献
12.
This paper investigates the utility of stable carbon and oxygen isotopes in human dental enamel to reveal patterns of breastfeeding and weaning in prehistory. Enamel preserves a record of childhood diet that can be studied in adult skeletons. Comparing different teeth, we used δ13C to document the introduction of solid foods to infant diets and δ18O to monitor the decline of breastfeeding. We report enamel carbonate δ13C and δ18O of 33 first molars, 35 premolars, and 25 third molars from 35 burials from Kaminaljuyú, an early state in the valley of Guatemala. The skeletons span from Middle Preclassic through Late Postclassic occupations, ca. 700 B.C. to 1500 A.D. Sections of enamel were removed from each tooth spanning from the cusp to the cemento-enamel junction. Stable isotope ratios were measured on CO2 liberated by reaction of enamel with H3PO4 in an automated carbonate system attached to a VG Optima mass spectrometer. Within a skeleton, teeth developing at older ages are more enriched in 13C and more depleted in 18O than teeth developing at younger ages. Premolars average 0.5% higher in δ13C than first molars from the same skeleton (P = 0.0001), but third molars are not significantly enriched over premolars. The shift from first molars to premolars may be due to the shift to solid foods from lipid-rich milk. After 2 years, when premolars begin to mineralize, the δ13C in childhood diets did not change systematically. First molars and premolars are similar in δ18O, but third molars average 0.7% lower than first molars (P = 0.0001) and 0.5% lower than premolars (P = 0.0003). First molar and premolar δ18O is heavier, because breast milk is more enriched in 18O than is drinking water. Hence, many children continued to nurse during the period of premolar formation. Together, these results indicate that Kaminaljuyú children had begun to eat solid maize foods before the age of 2 years but continued to drink breast milk until much later. Am J Phys Anthropol 106:1–18, 1998. © 1998 Wiley-Liss, Inc. 相似文献
13.
Fuller BT De Cupere B Marinova E Van Neer W Waelkens M Richards MP 《American journal of physical anthropology》2012,149(2):157-171
An isotopic reconstruction of human dietary patterns and livestock management practices (herding, grazing, foddering, etc.) is presented here from the sites of Düzen Tepe and Sagalassos in southwestern Turkey. Carbon and nitrogen stable isotope ratios were determined from bone collagen extracted from humans (n = 49) and animals (n = 454) from five distinct time periods: Classical‐Hellenistic (400–200 BC), Early to Middle Imperial (25 BC–300 AD), Late Imperial (300–450 AD), Early Byzantine (450–600 AD), and Middle Byzantine (800–1200 AD). The humans had protein sources that were based on C3 plants and terrestrial animals. During the Classical‐Hellenistic period, all of the domestic animals had δ13C and δ15N signatures that clustered together; evidence that the animals were herded in the same area or kept in enclosures and fed on similar foods. The diachronic analysis of the isotopic trends in the dogs, cattle, pigs, sheep, and goats highlighted subtle but distinct variations in these animals. The δ13C values of the dogs and cattle increased (reflecting C4 plant consumption) during the Imperial and Byzantine periods, but the pigs and the goats displayed little change and a constant C3 plant‐based diet. The sheep had a variable δ13C pattern reflecting periods of greater and lesser consumption of C4 plants in the diet. In addition, the δ15N values of the dogs, pigs, cattle, and sheep increase substantially from the Classical‐Hellenistic to the Imperial periods reflecting a possible increase in protein consumption, but the goats showed a decrease. Finally, these isotopic results are discussed in the context of zooarcheological, archeobotanical, and trace element evidence. Am J Phys Anthropol 149:157–171, 2012. © Wiley Periodicals, Inc. 相似文献
14.
JIN KYUNG KIM BOO‐KEUN KHIM KYUNG SIK WOO SEOK HOON YOON 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2010,43(2):170-181
Kim, J.K., Khim, B.‐K., Woo, K.S., & Yoon, S.H. 2009: Records of palaeo‐seawater condition from oxygen‐isotope profiles of early Pleistocene fossil molluscs from the Seoguipo Formation (Korea). Lethaia, Vol. 43, pp. 170–181. High‐resolution δ18O profiles of early Pleistocene fossil molluscs (Mizuhopecten tokyoensis hokurikuensis) from the shallow‐marine sedimentary Seoguipo Formation (Korea) were found to exhibit distinct annual cycles identified by their unique seasonality (δ18O amplitude). A direct comparison of fossil δ18O profiles with that of living shells (Amusium japonicum japonicumi) indicated that the palaeoseawater conditions differed from present‐day seawater. Specifically, the positive δ18O shift in the isotope profile of the fossil specimens relative to that of the living mollusc shell reflected that palaeotemperature was lower than that today. However, a comparison of the coldest palaeotemperatures (determined from the heaviest δ18O values of fossil shells), with the present‐day winter temperatures indicates that temperature variation alone cannot account for the entire positive δ18O offset. These findings indicate that variation in the seawater δ18Ow values plays a dominant role in the biogenic carbonate precipitation of fossils. Thus, the fossil shells obtained from stratigraphic units suggest different palaeoenvironmental conditions, including lower temperatures and 18O‐enriched glacial seawater, when compared with the present‐day conditions. The Seoguipo Formation records at least five cycles of relative sea‐level fluctuations, with changes in fossil δ18O amplitudes separated by sequence boundaries likely to reflect variations of unique palaeoseawater condition, although the oxygen‐isotope profile of fossil molluscs appears to provide a snap‐shot of the palaeoclimatic signature. □Early Pleistocene, mollusc fossils, oxygen isotope, palaeoenvironment, seawater temperature. 相似文献
15.
《Palaeogeography, Palaeoclimatology, Palaeoecology》2007,243(3-4):412-420
Oxygen isotope compositions of phosphate (δ18Op) were measured in tooth enamel from captive and wild individuals of 8 crocodilian species. A rough linear correlation is observed between the δ18Op of all the studied species and the oxygen isotope composition of ambient water (δ18Ow). Differences in mean air temperature, diet and physiology could contribute significantly to the large scatter of δ18Op values. The combination of these parameters results in a fractionation equation for which the slope (0.82) is lower than that expected (≥ 1) from predictive model equations that assume temperature and diet as fixed parameters. Taking into account large uncertainties, the observed oxygen isotope fractionation between phosphate and ambient water does not statistically differ from that formerly established for aquatic turtles. Case studies show that δ18Op values of fossil crocodile tooth enamel can be used to discriminate between marine and freshwater living environments within a precision of about ± 2‰ only. 相似文献
16.
David M. Snider Jason J. Venkiteswaran Sherry L. Schiff John Spoelstra 《Global Change Biology》2012,18(1):356-370
The ability to use δ18O values of nitrous oxide (N2O) to apportion environmental emissions is currently hindered by a poor understanding of the controls on δ18O–N2O from nitrification (hydroxylamine oxidation to N2O and nitrite reduction to N2O). In this study fertilized agricultural soils and unfertilized temperate forest soils were aerobically incubated with different 18O/16O waters, and conceptual and mathematical models were developed to systematically explain the δ18O–N2O formed by nitrification. Modeling exercises used a set of defined input parameters to emulate the measured soil δ18O–N2O data (Monte Carlo approach). The Monte Carlo simulations implied that abiotic oxygen (O) exchange between nitrite (NO2?) and H2O is important in all soils, but that biological, enzyme‐controlled O‐exchange does not occur during the reduction of NO2? to N2O (nitrifier‐denitrification). Similarly, the results of the model simulations indicated that N2O consumption is not characteristic of aerobic N2O formation. The results of this study and a synthesis of the published literature data indicate that δ18O–N2O formed in aerobic environments is constrained between +13‰ and +35‰ relative to Vienna Standard Mean Ocean Water (VSMOW). N2O formed via hydroxylamine oxidation and nitrifier‐denitrification cannot be separated using δ18O unless 18O tracers are employed. The natural range of nitrifier δ18O–N2O is discussed and explained in terms of our conceptual model, and the major and minor controls that define aerobically produced δ18O–N2O are identified. Despite the highly complex nature of δ18O–N2O produced by nitrification this δ18O range is narrow. As a result, in many situations δ18O values may be used in conjunction with δ15N–N2O data to apportion nitrifier‐ and denitrifier‐derived N2O. However, when biological O‐exchange during denitrification is high and N2O consumption is low, there may be too much overlap in δ18O values to distinguish N2O formed by these pathways. 相似文献
17.
O Nehlich BT Fuller N Márquez-Grant MP Richards 《American journal of physical anthropology》2012,149(1):115-124
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 δ13C and δ15N values by [Fuller et al.: Am J Phys Anthropol 143 (2010) 512–522] and focuses on using δ34S values to better understand the dietary patterns of these populations through time and to possibly identify immigrants to these islands. The range of δ34S 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 δ34S 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 δ34S 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 δ34S 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 δ34S values that indicate that they were immigrants to Ibiza who died before acquiring the new local sulfur isotopic signature. Am J Phys Anthropol 2012. © 2012 Wiley Periodicals, Inc. 相似文献
18.
We present new data of oxygen isotopes in marine sulfate (δ18OSO4) in pore fluid profiles through organic‐rich deep‐sea sediments from 11 ODP sites around the world. In almost all sites studied sulfate is depleted with depth, through both organic matter oxidation and anaerobic methane oxidation. The δ18OSO4 increases rapidly near the top of the sediments, from seawater values of 9 to maxima between 22 and 25, and remains isotopically heavy and constant at these values with depth. The δ18OSO4 in these pore fluid profiles is decoupled from variations in sulfur isotopes measured on the same sulfate samples (δ34SSO4); the δ34SSO4 increases continuously with depth and exhibits a shallower isotopic increase. This isotopic decoupling between the δ34SSO4 and the δ18OSO4 is hard to reconcile with the traditional understanding of bacterial sulfate reduction in sediments. Our data support the idea that sulfate or sulfite and water isotopically exchange during sulfate reduction and that some of the isotopically altered sulfur pool returns to the environment. We calculate that the rapid increase in the δ18OSO4 in the upper part of these sediments requires rates of this oxygen isotope exchange that are several orders of magnitude higher than the rates of net sulfate reduction calculated from the sulfate concentration profiles and supported by the δ34SSO4. We suggest several mechanisms by which this may occur, including ‘net‐zero’ sulfur cycling, as well as further experiments through which we can test and resolve these processes. 相似文献
19.
Stable nitrogen isotope analysis of dentine serial sections elucidate sex differences in weaning patterns of wild chimpanzees (Pan troglodytes)
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Geraldine E. Fahy Michael P. Richards Benjamin T. Fuller Tobias Deschner Jean‐Jacques Hublin Christophe Boesch 《American journal of physical anthropology》2014,153(4):635-642
Offspring provisioning is one of the most energetically demanding aspects of reproduction for female mammals. Variation in lactation length and weaning 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) in Taï National Park, Côte d'Ivoire, to quantify weaning in these chimpanzees and explore if infant sex plays a role in maternal investment. We analyzed serial sections of deciduous lateral incisor root dentine from four Taï chimpanzees to establish the δ15N signal of nursing infants; we then analyzed serial sections of first permanent mandibular molar root dentine from 12 Taï chimpanzees to provide quantitative δ15N data on weaning in this population. Up to 2 years of age both sexes exhibited dentine δ15N values ≈2–3‰ higher than adult female Taï chimpanzees, consistent with a nursing signal. Thereafter a steady decrease in δ15N values consistent with the onset, and progression, of weaning, was visible. Sex differences were also evident, where male δ15N values decreased at a significantly slower rate compared to females. Confirmation of sex differences in maternal investment among Taï chimpanzees, demonstrates the viability of using isotope analysis to investigate weaning in non‐human primates. Additionally, assuming that behaviors observed in the Taï 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, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
20.
Annual variability in dentin δ15N and δ13C reveal sex differences in weaning age and feeding habits in Risso's dolphins (Grampus griseus)
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Florence Chan Evacitas Wen‐Yuan Kao Graham A. J. Worthy Lien‐Siang Chou 《Marine Mammal Science》2017,33(3):748-770
Teeth of odontocetes accumulate annual dentinal growth layer groups (GLGs) that record isotope ratios, which reflect the time of their synthesis. Collectively, they provide lifetime records of individual feeding patterns from which life history traits can be inferred. We subsampled the prenatal dentin and postnatal GLGs in Risso's dolphins (Grampus griseus) (n = 65) that stranded or were collected as bycatch in Taiwan (1994–2014) and analyzed them for δ15N and δ13C. Age‐specific δ15N and δ13C values were corrected for effects of calendar year, stranding site, C/N, and sex. δ15N values were higher in prenatal layers (14.94‰ ± 0.74‰) than in adult female GLGs (12.58‰ ± 0.20‰), suggesting fetal enrichment during gestation. Decreasing δ15N values in early GLGs suggested changes in dietary protein sources during transition to complete weaning. Weaning age was earlier in males (1.09 yr) than in females (1.81 yr). Significant differences in δ15N values between weaned males and females suggest potential sexual segregation in feeding habits. δ13C values increased from the prenatal to the 4th GLG by ~1.0‰, indicative of a diet shift from 13C‐depleted milk to prey items. Our results provide novel insights into the sex‐specific ontogenetic changes in feeding patterns and some life history traits of Risso's dolphins. 相似文献