Article

Oxygen isotopic determination of climatic variation using phosphate from beaver bone, tooth enamel, and dentine

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

The δ18O of Canadian beaver (Castor canadensis) teeth should reflect variations in the isotopic composition of the water in which the beavers live, as their incisors grow rapidly and continuously. We observe seasonal variations in phosphate δ18O using samples of enamel taken along the length of single teeth. In the spring the δ18O of the enamel being deposited gradually declines, reflecting a retarded input of δ18O depleted winter water. After mid-year, enamel δ18O is higher than average (as represented by the δ18O of bone phosphate from the same animal) and passes through a maximum in late summer or early fall. Overall, the amplitude of seasonal excursions in enamel δ18O (4‰) is much smaller than the expected summer-winter range in the δ18O of meteoric water (> 10‰). This is because hydrologic mixing processes, gradual admixing of environmental water with beaver body water, long-term plant growth, and oxygen inputs of relatively constant value (particularly atmospheric oxygen) tend to even out summer-winter differences in the δ18O of oxygen inputs to the beaver. The δ18O of bone from adult beavers was uniform at 11.9 ± 0.5‰ over the study area. Analyses of a Sangamon age giant beaver (Castoroides ohioensis) incisor from Hopwood Farm, Illinois, show a slightly larger 5.5‰ seasonal cycle of δ18O with an average enamel δ18O of 18‰. This suggests that average temperatures were warmer during the Sangamon than today and that seasonal temperature differences and/or relative humidity variations were larger.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Furthermore, since enamel is not subjected to remodelling as is the case for bone, the isotope composition of enamel increments reflects relatively discrete intervals of time. The stable light isotopes of oxygen ( 18 O/ 16 O) obtained from skeletal tissues such as bones and teeth provide information relating to environmental fluctuations in meteoric water, with a series of biological filters related to the drinking behaviour (Luz et al., 1984; Luz and Kolodny, 1985; Fricke et al., 1998; Sponheimer and Lee-Thorp, 2001 ) or thermophysiology of a species (Kohn, 1996; Stuart-Williams and Schwarcz, 1997). Meteoric water (either surface, flu-vial, or lacustrine) is usually the main source of ingested water, although many species rely heavily on leafwater. ...
... The isotopic composition of meteoric water is sensitive to a series of climatic factors including oceanic source, latitude and mean annual temperature (Dansgaard, 1964). As the isotopic composition of skeletal tissues is mainly controlled by the d 18 O value of body water, these tissues can be used to obtain information relating to environmental temperature and precipitation (Luz and Kolodny, 1985; Bocherens et al., 1996; Stuart-Williams and Schwarcz, 1997). In addition, d 18 O variations amongst different animals in one area can provide indirect information about habitat, foraging preferences, and thermophysiological adaptations (Bocherens et al., 1996; Kohn, 1996; Sponheimer and Lee-Thorp, 2001). ...
... The intra-tooth variation in the C. niloticus teeth (up to 3x) is similar to the findings in previous studies conducted on extant and historic mammals (Balasse et al., 2002) in the Western Cape. Elsewhere, several studies of mammalian teeth, including a study of continuously growing beaver teeth (Stuart-Williams and Schwarcz, 1997 ), extant sheep and 500- year-old bison (Fricke and O'Neil, 1996 ), and Holocene horse enamel phosphate (Sharp and Cerling, 1998) have shown intra-tooth variability on the order of 3–3.6x. Notwithstanding that amplitude of variability would be expected to be greater at higher latitudes, in combination, it suggests that reptiles may in effect exhibit a similar variability compared to mammals in a region. ...
Article
The palaeoecology of the coeval Middle Triassic non-mammalian cynodonts, Diademodon and Cynognathus (Therapsida) remains poorly understood although their gross morphology has been studied intensively. Significant differences in their growth patterns suggest inherent biological differences, despite having inhabited similar environments. In this study, the palaeoecology of Cynognathus and Diademodon specimens were examined using intra-tooth stable carbon and oxygen isotope analyses of enamel carbonate. The resulting stable isotope patterns of Cynognathus and Diademodon were compared with that of Crocodylus niloticus and published mammalian tooth enamel data. Predictably, the non-mammalian cynodont d13C values fall within the expected range for C3 plant diets. Both d18O and d13C values of Diademodon are markedly more depleted than those of Cynognathus, suggesting that the former fed in shadier, damper areas, was nocturnal and/or depended more directly on environmental water. The seasonal amplitude reflected in the Cynognathus teeth is relatively low. However, high amplitude, directional d18O intra-tooth variations in the Diademodon teeth are comparable to, or higher than, those observed for extant mammalian and C. niloticus teeth from semi-arid, seasonal regions. This suggests that marked seasonality prevailed in the Karoo Basin during the Middle Triassic, and that Diademodon was sensitive to these variations. These isotopic differences between Diademodon and Cynognathus indicate differing responses to climatic fluctuations and reveal new insights into the palaeoecology of non-mammalian cynodonts.
... Intra-and inter-individual variation in the isotopic values of mammalian dental tissues provides information about the seasonal dynamics of animal herds and has been used to infer changes in diet, habitat, birth season, and mortality (e.g., Koch et al., 1989;Bryant et al., 1996;Stuart-Williams and Schwarcz, 1997;Balasse et al., 2003;Hoppe, 2004;Fisher and Fox 2007;Knipper et al., 2008;Feranec et al., 2009;Julien et al., 2012;Rountrey et al., 2012). ...
... Conversely, a low variability between individuals would suggest individuals living under similar conditions and would therefore be consistent with individuals related to the same group or population (Koch et al., 1989(Koch et al., , 1998Bryant et al., 1996;Hoppe, 2004;Fenner, 2008Fenner, , 2009Cerling et al., 2009;Wittemyer et al., 2009). In addition, intra-individual variations in oxygen isotopic values from dental tissues have been successfully used to decipher the seasonality of death of fossil mammals (Koch et al., 1989;Stuart-Williams and Schwarcz, 1997;Fisher and Fox, 2007;Knipper et al., 2008;Julien, 2009). ...
... Horses are obligate drinkers, obtaining a large proportion of oxygen from drinking water in comparison to plants, resulting in a more dampened d 18 O recorded signal than other non-obligate drinker herbivores (Bryant and Froelich, 1995;Nelson, 2005;Wang et al., 2008a, b). The low amplitude of intra-tooth d 18 O variation can also indicate buffered water supplies of Sch€ oningen horses such as lakes or swamps (Stuart-Williams and Schwarcz, 1997;Sharp and Cerling, 1998). Considering the context of discovery of the sampled teeth, we cannot exclude the possibility that the horses took at least part of their drinking water from the lake of Sch€ oningen (with springs as important sources of water supply), resulting in a slight dampening of the recorded d 18 O values. ...
... En vertebrados, estos isótopos se obtienen preferentemente del esmalte dental, compuesto en más de un 95% por mineral de bioapatita, o hidroxiapatita (Koch 2007 (Luz et al. 1984;Koch et al. 1989;Stuart-Williams and Schwarcz 1997;Frickle et al. 1998;Hoppe et al. 2004;Fisher y Fox 2007;Koch 2007;Britton et al. 2009;Fabre et al. 2011;Julien et al. 2012Julien et al. , 2015Domingo et al. 2015;Yravedra et al. 2016b). ...
... Aun así, en ocasiones el esmalte sufre alteraciones, sobre todo cuando el diente no está completamente formado y/o el esmalte no está mineralizado. En cambio, el proceso de mineralización del esmalte atenúa el valor de la señal isotópica del bioapatito, lo que podría interpretarse erróneamente como una menor variación de la temperatura local si no se corrige (Luz et al. 1984;Koch et al. 1989;Kohn 1996;Stuart-Williams and Schwarcz 1997;Frickle et al. 1998;Hoppe et al. 2004;Koch 2007;Britton et al. 2009;Fabre et al. 2011;Julien et al. 2012Julien et al. , 2015Domingo et al. 2015;Yravedra et al. 2016b). ...
... El principal isótopo utilizado en estudios paleoclimáticos, paleoecológicos y estacionales es δ 18 O. Se explica porque: 1) el δ 18 O p-c del bioapatito dependen del valor isotópico del δ 18 O del agua corporal (δ 18 O ac ) de los mamíferos terrestres, precipitando en equilibrio a temperatura corporal (Luz et al. 1984;Koch et al. 1989;Kohn 1996;Stuart-Williams and Schwarcz 1997;Koch 2007;Britton et al. 2009;Fabre et al. 2011). ...
Article
Full-text available
A mediados del siglo XX, los métodos de los estudios de estacionalidad surgieron para intentar establecer el momento del año y el tiempo de ocupación en el que se habitaron los yacimientos arqueológicos. Sin embargo, las limitaciones de estas técnicas, basadas fundamentalmente en restos óseos fósiles, han dificultado la interpretación de estos datos. Este trabajo hace una relación de la mayoría de métodos utilizados para los estudios estacionales hasta la fecha, para facilitar su comprensión y su futura aplicación, destacando las virtudes y los defectos de cada uno.
... There is also a trophic level effect (higher δ 18 O values) in breastfeeding infants (Wright & Schwarcz, 1998;White et al., 2000White et al., , 2003. Not surprisingly, seasonality in climate and/or water sources can produce significant variability in their δ 18 O values (Luz et al., 1990;Stuart-Williams & Schwarcz, 1997). ...
... Until recently, oxygen-isotope analysis was used mainly on animal tissues and shells to reconstruct paleoenvironmental change over both longterm and short-term (season) periods (Koch et al., 1989;Fricke & O'Neil, 1996;Stuart-Williams & Schwarcz, 1997;Fricke et al., 1998;Weideman et al., 1999;Gadbury et al, 2000;Bocherens et al., 2001), to understand the relationship between animal physiology, diet, and the environment (e.g., Bocherens et al., 1996;Kohn et al., 1996;Sponheimer & Lee-Thorp, 1999), and to reconstruct migratory patterns in fish and animals (Killingly & Lutcavage, 1983;Nelson et al., 1989;Meyer-Rochow et al., 1992;Hobson, 1999). Because species size, physiology, and dietary behavior affect the oxygen-isotope composition of animals (Bryant & Froelich, 1995, δ 18 O values are not necessarily comparable among species. ...
... Reconstruction of seasonality in climate change using oxygen-isotope ratios (and in some cases carbon-isotope ratios) in teeth has been done for a variety of animals (e.g., Koch et al., 1989;Bryant et al., 1996;Cerling & Sharp, 1996;Fricke & O'Neil, 1996;Fricke et al., 1996;Stuart-Williams & Schwarcz, 1997;Weiderman et al., 1999;Gadbury et al., 2000). Isotopic analysis of animal teeth in the Maya area is a ripe area of study (recall also that teeth are most often better preserved than bone). ...
Article
Full-text available
Stable isotope analysis of human skeletons has been used succesfully for years to determine the quatity and kind of animals consumed as food, even in the humid tropics where skeletal material may not be diagnostically useful for many other things. This paper discusses the largely unrealized potential, and the pros and cons, of using stable isotopic analysis of animals to answer questions about humans. Animáis share the same ecosystem with humans and are often incorporated into social and ideological systems. The paper examines the use of intentionally fed animals as proxies for humans where human material is politically or archaeologically unavailable; it also reviews other aspects of ancient life, including the role of animals in the exercise of ideological practice, human-animal relationships involved in hunting, synathropy, domestication, and husbanding, and the use of animals as barometers of human-induced and natural environmental change. The examples in the paper are taken from isotopic analyses at various Maya sites.
... Intra-and inter-individual variation in the isotopic values of mammalian dental tissues provides information about the seasonal dynamics of animal herds and has been used to infer changes in diet, habitat, birth season, and mortality (e.g., Koch et al., 1989;Bryant et al., 1996;Stuart-Williams and Schwarcz, 1997;Balasse et al., 2003;Hoppe, 2004;Fisher and Fox 2007;Knipper et al., 2008;Feranec et al., 2009;Julien et al., 2012;Rountrey et al., 2012). ...
... Conversely, a low variability between individuals would suggest individuals living under similar conditions and would therefore be consistent with individuals related to the same group or population (Koch et al., 1989(Koch et al., , 1998Bryant et al., 1996;Hoppe, 2004;Fenner, 2008Fenner, , 2009Cerling et al., 2009;Wittemyer et al., 2009). In addition, intra-individual variations in oxygen isotopic values from dental tissues have been successfully used to decipher the seasonality of death of fossil mammals (Koch et al., 1989;Stuart-Williams and Schwarcz, 1997;Fisher and Fox, 2007;Knipper et al., 2008;Julien, 2009). ...
... Horses are obligate drinkers, obtaining a large proportion of oxygen from drinking water in comparison to plants, resulting in a more dampened d 18 O recorded signal than other non-obligate drinker herbivores (Bryant and Froelich, 1995;Nelson, 2005;Wang et al., 2008a, b). The low amplitude of intratooth d 18 O variation can also indicate buffered water supplies of Sch€ oningen horses such as lakes or swamps (Stuart-Williams and Schwarcz, 1997;Sharp and Cerling, 1998). Considering the context of discovery of the sampled teeth, we cannot exclude the possibility that the horses took at least part of their drinking water from the lake of Sch€ oningen (with springs as important sources of water supply), resulting in a slight dampening of the recorded d 18 O values. ...
... The short limbs and bulky body of Castoroides made it poorly adapted to a life spent predominantly on land and it must have relied on access to the water for shelter from terrestrial predators 13 . Previous studies based on stable isotope analysis of single specimens suggest that the giant beaver consumed aquatic vegetation, and thrived in mid-latitude regions of North America during warm, strongly seasonal conditions between 125,000 and 75,000 BP 14,15 . Other studies hypothesize that the giant beaver was a relatively cold-tolerant species, preferentially consumed emergent macrophytes, and lived in ponds and shallow lakes bordered by marshlands [16][17][18][19] . ...
... The 15 N-enrichment of the nitrogen baseline observed in the Mammoth Steppe grasslands was induced by factors that would not have been nearly as pronounced in Pleistocene wetland ecosystems, or wetter, forested ecosystems with lower megafauna population densities. Late Pleistocene mastodon and giant beaver populations, for example, were contemporary in Yukon Territory and in the Great Lakes region of North America 48,49 . ...
... In addition, the relative nitrogen isotope pattern of each plant functional group should remain the same, despite changes in nitrogen baseline δ 15 N. Aquatic plants (submerged, emergent, and floating macrophytes), for example, should have, on average higher δ 15 N than terrestrial plants on account of their access to more 15 N-enriched sources of bioavailable nitrogen. ...
Article
Full-text available
This is a multi-individual (n = 11), stable carbon and nitrogen isotope study of bone collagen (δ13Ccol and δ15Ncol) from the giant beaver (genus Castoroides). The now-extinct giant beaver was once one of the most widespread Pleistocene megafauna in North America. We confirm that Castoroides consumed a diet of predominantly submerged aquatic macrophytes. These dietary preferences rendered the giant beaver highly dependent on wetland habitat for survival. Castoroides’ δ13Ccol and δ15Ncol do not support the hypothesis that the giant beaver consumed trees or woody plants, which suggests that it did not share the same behaviours as Castor (i.e., tree-cutting and harvesting). The onset of warmer, more arid conditions likely contributed to the extinction of Castoroides. Six new radiocarbon dates help establish the chronology of the northward dispersal of the giant beaver in Beringia, indicating a correlation with ice sheet retreat.
... Intra-tooth δ 18 O bioapatite values presenting in sinusoidal patterns are most commonly interpreted as reflecting the seasonal variation of δ 18 O precipitation , with increased δ 18 O values linked to summer (Fricke and O'Neil, 1996;Kohn et al., 1998;Stuart-Williams and Schwarcz, 1997). In Tasmania, this interpretation is supported by the historically averaged Global Network of Isotopes in Precipitation (GNIP) data from Cape Grim on the far northwest coast (IAEA/WMO, 2019) (1979-2002) (Fig. 3), historical data from Margate, 20 km south of Hobart in southeast Tasmania (Treble et al., 2005), and isoscape modelling by Bowen (2013Bowen ( , 2010 fractionation resulting from metabolic processes and tissue formation (Iacumin et al., 1996;Longinelli, 1984;Luz et al., 1984). ...
... The resolution at which isotopic data can be recovered from wombat teeth was investigated by evaluating variation in dental growth rates. Dental growth was estimated using a method based on the peak and trough mode described by Fricke and O'Neil (1996) and Stuart-Williams and Schwarcz (1997), where the enriched 'peak' of the seasonal sinusoidal curve is attributed to summer and the corresponding trough to the depleted values of winter. Growth rates were assessed using the following Eq. ...
Article
Archaeologists and palaeoecologists are increasingly turning to stable isotope analysis (δ ¹³ C, δ ¹⁸ O) of fossil bioapatite to examine interactions of human and animal populations. However, relatively few investigations have focussed on the identification of natural variation in comparable modern populations, particularly within the Australian context. In this paper, we present the first modern isotopic reference dataset for Tasmanian bare-nosed wombat teeth (Vombatus ursinus tasmaniensis). Samples for δ ¹³ C bioapatite and δ ¹⁸ O bioapatite measurements were recovered sequentially at sub-monthly resolution from all tooth types. δ ¹³ C bioapatite showed little variation within a seasonal sinusoidal pattern within the sample set (n = 24 wombats; 35 teeth) due to the homogeneous C 3 distribution of plants in Tasmania. In contrast, δ ¹⁸ O bioapatite profiles varied seasonally, representing time periods of between 0.9 and 2.1 years in 95% of the sample. Significant differences between tooth types were found from intra-individual to inter-regional scales for both dental growth rates and isotopic values. The accuracy of season-of-death assessments differed across the island; those in eastern Tasmania were accurate in all instances whereas those in the west showed substantial inaccuracies. We suggest that this may be due to the elodont form of wombat dentition and the ecologically influenced seasonally varied diet in western Tasmania. As the rate of dental growth is positively correlated with the proportion of coarse vegetation within the diet, this seasonal variation is therefore likely to change how annual isotopic signals are incorporated into the enamel. These results highlight the need to understand the degree of species-specific isotopic variation at a range of scales before applying this technique to archaeological or palaeontological assemblages.
... Intrapopulational variation in 6180 values (deer, wild boar, pigs) and humans appears to be quite low generally, i.e., 1 /oo (Longinelli 1984). However, variations can be significant especially in species that are dietarily heterogeneous or geographically mobile (Luz, Cormie, and Schwarcz 1990;Stuart-Williams and Schwarcz 1997). ...
... The first molar mineralizes between birth and age th the third between ages nine and twelve (Massler, Schour, and Ponch Moorees, Fanning, and Hunt 1963). Seasonal variation has been found in values along the length of mammalian teeth (Cerling and Sharp 1996;Fri O'Neil 1996;Stuart-Williams and Schwarcz 1997). However, because who were analyzed in our study, any seasonal effects or geographic relocation wi three-year periods of formation for both tooth types have been masked. ...
Article
Full-text available
Oxygen-isotope ratios of enamel phosphate from a sample of first and third molars from burials in the important state of Kaminaljuyú, Guatemala, have been used to identify individuals who were born in foreign regions or who relocated during late childhood. The goal of this research is to clarify the nature of the influence exercised by the larger Mesoamerican state of Teotihuacán, Mexico. A baseline that is isotopically distinct from the Valley of Mexico (Teotihuacán), the Valley of Oaxaca (Monte Alban), and the Petén (Río Azul/Río Bravo) has been established for the Kaminaljuyú environment using burials assumed to be representative of the local population from the Preclassic (1000-500 B.C.) to Postclassic (A.D. 1000-1500) periods. As expected, the greatest degree of isotopic variation is found in the Middle Classic period, but "foreigners" are not restricted to the well-known tombs in Mounds A and B, which exhibit many Teotihuacán material culture affinities. Only one skeleton has a δ18Op value in late childhood that is consistent with Teotihuacán values; it is a principal tomb occupant. Therefore, it is unlikely that Mounds A and B represent a group of Teotihuacán immigrants, whether rulers, traders, or ambassadors. In addition, the δ18Op values indicate the presence of a second group of foreigners or foreign sojourners for whom a homeland is not yet unidentified.
... In archaeological research, human bone and enamel samples are commonly used to investigate changes in drinking water source (d 18 O p and d 18 O sc ) and to infer changes in place of residence based on natural variability in environmental water isotopic composition (inter alia Buzon et al., 2012;Chenery et al., 2010;Dupras and Schwarcz, 2001;Fricke et al., 1995;Hewitt, 2013;Knudson, 2009;Knudson et al., 2009;Mitchell and Millard, 2009;Perry et al., 2009;Schwarcz et al., 1991;Smits et al., 2010;Webb, 2010;Webb et al., 2013;White et al., 1998White et al., , 2000White et al., , 2002White et al., , 2004aWhite et al., , 2004bWhite et al., , 2007. This research is based on the well-established relationship between the oxygenisotope compositions of mammalian body tissues and consumed water, including drinking water and, to a lesser extent, food water and respired oxygen (Bryant and Froelich, 1995;Luz and Kolodny, 1985;Stuart-Williams and Schwarcz, 1997). Drinking water oxygen-isotope values (d 18 O dw ) reflect the isotopic composition of environmental water, including both meteoric and recycled water (Luz and Kolodny, 1985;Stuart-Williams and Schwarcz, 1997), and this isotopic ratio is incorporated into body tissues (adjusted by a metabolic fractionation factor). ...
... This research is based on the well-established relationship between the oxygenisotope compositions of mammalian body tissues and consumed water, including drinking water and, to a lesser extent, food water and respired oxygen (Bryant and Froelich, 1995;Luz and Kolodny, 1985;Stuart-Williams and Schwarcz, 1997). Drinking water oxygen-isotope values (d 18 O dw ) reflect the isotopic composition of environmental water, including both meteoric and recycled water (Luz and Kolodny, 1985;Stuart-Williams and Schwarcz, 1997), and this isotopic ratio is incorporated into body tissues (adjusted by a metabolic fractionation factor). Carbon-isotope data (d 13 C sc ) are further used to reconstruct diet and dietary change between childhood and adulthood, and, with carbon-and nitrogen-isotope compositions of protein, can be used to create a more informative dietary reconstruction. ...
Article
In archaeological research, human bone and enamel bioapatite isotopic compositions are commonly used to reconstruct residential and dietary histories. In doing so, enamel and bone bioapatite are implicitly treated as isotopically equivalent, but recent research has determined that carbonate–carbon and –oxygen isotopic compositions of these two tissues may be offset by several per mil. Here, we compare the isotopic compositions of co-forming bone and enamel from juvenile humans. We also assess the impact of a standard pre-treatment procedure for the removal of organic matter and exogenous carbonates on carbon- and oxygen-isotope compositions and on bioapatite crystallinity and carbonate content. Pre-treatment procedures had minimal effect on both enamel and bone carbon and oxygen isotopic compositions (±0.4–±0.9‰) and bioapatite crystallinity, and effectively removed exogenous carbonates. The offset between enamel and bone phosphate–oxygen isotopic compositions is relatively small (±0.7 ± 0.5‰). The offsets for carbonate–oxygen (+1.4 ± 1.0‰) and –carbon (+4.3 ± 1.2‰) are larger, and enamel is consistently 18O- and 13C-enriched relative to bone. Interpreted conservatively, phosphate–oxygen isotopic data from paired enamel and bone remain suitable for determining residential history, whereas the isotopic compositions of carbonate–oxygen and –carbon from enamel and bone bioapatite are inherently different and cannot be compared uncritically.
... In contrast, the application of oxygen (d 18 O) isotope techniques to archaeological, anthropological and palaeoecological case studies have largely focused on reconstructions of palaeotemperature and palaeoclimate (e.g. Longinelli 1984;D'Angela and Longinelli 1990;Bryant et al. 1994;S anchez Chill on et al. 1994;Delgado Huertas et al. 1995;Stuart-Williams and Schwarcz 1997;Genoni et al. 1998;Longinelli et al. 2003;Mannino et al. 2003;Hoppe et al. 2004;Hoppe 2006;Bernard et al. 2009) and also, through this, their use as a tool to determine geographical provenience and mobility in humans (e.g. White et al. 2000;Evans et al. 2006aEvans et al. , 2006bEckardt et al. 2009;Chenery et al. 2010) and wild and domestic animals (e.g. ...
... Generally considered to be less prone to diagenetic alteration than the oxygen-bearing carbonate fraction of the skeleton (Kolodny et al. 1983;Luz et al. 1984;Nelson et al. 1986;Kohn et al. 1999), analysis of oxygen isotope ratios in bone phosphate offers the potential for the reconstruction of breastfeeding and weaning practices where collagen is not preserved. Furthermore, analysis of bone phosphate in adult humans could permit the reconstruction of mean annual temperatures, as demonstrated in other mammalian species (Longinelli 1984;Luz et al. 1984;Ayliffe and Chivas 1990;S anchez Chill on et al. 1994;Stuart-Williams and Schwarcz 1997). However, despite the strength of the P-O bonds within the PO 4 component, the recrystallization of the nano-crystalline bone bioapatite and isotope exchange with ambient pore fluids may render the material unsuitable for such studies due to chemical alteration in the burial environment (T€ utken et al. 2008). ...
Article
Here we report bone phosphate oxygen (δ(18) Op ) values from perinates/neonates and infants (<3.5 years; n = 32); children (4-12 years; n = 12); unsexed juveniles (16-18 years; n = 2); and adult bones (n = 17) from Wharram Percy, North Yorkshire, England, in order to explore the potential of this method to investigate patterns of past breastfeeding and weaning. In prior studies, δ(15) N and δ(13) C analyses of bone collagen have been utilized to explore weaning age in this large and well-studied assemblage, rendering this material highly appropriate for the testing and development of this alternative method targeting the inorganic phase of bone. Data produced reveal (18) O-enrichment in the youngest perinatal/neonatal and infant samples, and an association between age and bone δ(18) Op (and previously-published δ(15) N values), with high values in both these isotope systems likely due to breastfeeding. After the age of 2-3 years, δ(18) Op values are lower, and all children between the ages of 4 and 12, along with the vast majority of sub-adults and adults sampled (aged 16 to >50 years), have δ(18) Op values consistent with the consumption of local modern drinking water. The implications of this study for the reconstruction of weaning practices in archaeological populations are discussed, including variations observed with bone δ(15) Ncoll and δ(18) Op co-analysis and the influence of culturally-modified drinking water and seasonality. The use of this method to explore human mobility and palaeoclimatic conditions are also discussed with reference to the data presented. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
... Additionally, part of the hydroxyl ions may be replaced by carbonate ions in a proportion of 2:1 (A-type substitution), resulting in the following approximate composition: [19,20]. Because most of the oxygen in hydroxyapatite is incorporated in the phosphate ions and because the P-O bonds are stronger and thought to be more resistant to diagenesis, many isotopic studies focused on the phosphate ions using their oxygen isotopic ratio (δ 18 O P ) as a proxy [13,16,21,22]. However, the analytical procedure is time-consuming and, therefore, analyzing the oxygen isotopic ratio (δ 18 O C ) of the structural carbonate in the tooth enamel is more cost effective. ...
Article
In this study, we present a correlation between δ¹⁸OC values of carbonate in tooth enamel samples from the modern Brazilian population and the available δ¹⁸ODW data for the meteoric water from the Global Network of Isotopes in Precipitation (GNIP). Tooth enamel from 119 Brazilian individuals from five different regions of the country were analyzed. The δ¹⁸OC isoscape obtained is in good agreement with the isoscape based on regional meteoric and drinking water. The regression matrix obtained for the δ¹⁸O values of the carbonate tooth enamel and meteoric water was used to build an isoscape using the regression-kriging approach. Our data show that Brazil can be divided in two main regions with respect to the δ¹⁸O values of the carbonate tooth enamel: (1.) the most easterly part of the northeast region, which is characterized by a warm and dry climate and (2.) the remainder of the country, stretching from the Amazon rain forest to the more southernly regions. The data herein reported can be used for forensic purposes related to human identification.
... Although oxygen is present in bone collagen, δ 18 O analysis of archaeological bone collagen is not feasible due to the likelihood of contamination 35. E.g., Fricke and O'Neil 1996;Stuart-Williams and Schwarcz 1997. 36. ...
... Additionally, enamel apatite is systematically laid down over months and seasons, proceeding down and out from crown top to crown bottom, although the enamel maturation phase introduces an element of mixing and hence dampening the main signature (Suga 1982;Sakae & Hirai 1982;HillSon 1986;BalaSSe 2002). Sampling the whole tooth crown provides a composite isotopic signature of these seasons, while serial sampling down the surface of the tooth crown potentially extracts inter-seasonal isotopic signatures (e.g., Stuart-williamS & ScHwarcz 1997;wiedemann et al. 1999;BalaSSe 2002). ...
Article
Archaeological sites in the Shashe-Limpopo River Basin, southern Africa, reflect marked population growth and increased socio-political complexity between ca AD 880 and 1290, but the nature of agropastoral management that underpinned these extensive, more complex societies is not well understood. One key question concerns whether localized or more widespread regional strategies were employed to manage large herds of domestic animals. In order to identify potential herding areas we carried out strontium isotope analyses on tooth enamel from domestic fauna recovered at Shashe-Limpopo River Basin sites and compared them with those of modern wild and domestic fauna sampled from the greater region. Values were determined via low-resolution Inductively-Coupled Plasma Mass Spectrometry (ICP-MS) and Laser-ablation ICP-MS and high-resolution, standard Thermal Ionization Mass Spectrometry (TIMS). The low-resolution approaches gave values comparable to data produced by TIMS, within the level of precision required to distinguish geological areas contained in this exceptionally isotopically variable environment. The less invasive laser-ablation ICP-MS method provided a means to sample tooth enamel increments for indications of inter-seasonal movement of livestock. The archaeological data suggest that an inter-seasonal geographical expansion of herd management took place as socio-political complexity increased. A trans-humance or relocating herding strategy would have limited overgrazing of the local river basin landscape and results allow us to revisit hypotheses that overgrazing and environmental deterioration contributed to the subsequent political collapse and abandonment of the river basin at ca AD 1290.
... In comparison with other osseous tissues, due to its high mineral content enamel is less susceptible, but not immune, to diagenetic alteration. The reliability of the isotopic signatures was examined by comparing values obtained from different osseous tissues and by using the trend of intra-tooth variations as well as the proportions of carbonate content (Wang and Cerling, 1994;Koch et al., 1997;Stuart-Williams and Schwarcz, 1997;Kohn et al., 1999;Lee-Thorp and Sponheimer, 2003;Zazzo et al., 2004;Tütken and Vennemann, 2011 (Fig. 6). This plateau corresponds to a zone of the tooth crown located near the root enamel junction where the enamel is thinner, and could reflect some effect of diagenesis on the seasonal signal or a less attenuated signal reflecting a shorter period of time. ...
... In comparison with other osseous tissues, due to its high mineral content enamel is less susceptible, but not immune, to diagenetic alteration. The reliability of the isotopic signatures was examined by comparing values obtained from different osseous tissues and by using the trend of intra-tooth variations as well as the proportions of carbonate content (Wang and Cerling, 1994;Koch et al., 1997;Stuart-Williams and Schwarcz, 1997;Kohn et al., 1999;Lee-Thorp and Sponheimer, 2003;Zazzo et al., 2004;Tütken and Vennemann, 2011 (Table 3). A tendency towards more positive d 18 O for dentine and cementum in comparison with enamel has been observed for a larger sample from the same collection (cf. ...
... Precipitation δ 18 O varies seasonally with ambient temperature at high and middle latitudes (Gat 1980, Rozanski et al. 1993. These seasonal changes are tracked in tooth mineral during growth, resulting in variability in the δ 18 O of bioapatite within a tooth row (Bryant et al. 1996a;Bryant et al. 1996b;Fricke and O'Neil 1996) and within a tooth (Koch et al. 1989;Fricke and O'Neil 1996;Stuart-Williams and Schwarcz 1997;Kohn et al., 1998;Sharp and Cerling 1998;Sharma et al. 2004;Nelson 2005;van Dam and Reichart, 2009;Bernard et al., 2009). Because the timing of tooth growth is fixed within a species, distinct patterns of variation in enamel δ 18 O within tooth rows reflect different seasons of birth, as exposed for the first time by Bryant et al. (1996a;1996b) in their studies of fossil populations of equids. ...
Article
Intra‐tooth sequential analysis of enamel δ18O is currently used to investigate birth seasonality in past animal populations, offering new insights into seasonal availability of animal resources, herd management and seasonality of site occupation. Reference data sets are still required to address two major difficulties: (1) that inter‐individual variability in the record of the seasonal cycle is affected by tooth size; and (2) that the season of birth cannot be directly estimated from the timing of tooth growth, because of a delay in enamel mineralization. We present a data set acquired on the lower second molar of 10 modern sheep from Rousay (Orkney) born within a few weeks of each other in April/May and submitted to the same environmental conditions until death. All sheep have recorded a sinusoidal pattern of δ18O variation spanning approximately a year. From the difference between the expected and the measured time sequence, the delay of enamel mineralization is estimated to be 5–6 months. The data set is then described using a model mainly based on a cosine function. The period, corresponding to the length of the M2 crown formed over a year, averaged 35.8 mm. A very slight variation of tooth growth rate with time and no attenuation of the isotopic signal towards the cervical margin of the crown could be detected in this data set. The lowest δ18O values, corresponding to the sheep's first winter, were tracked at a distance from the enamel/root junction that varied between 23.0 and 30.3 mm (xmin mean = 27.6 mm); the highest δ18O values, corresponding to the sheep's second summer, were between 6.3 and 11.6 mm (xmax mean = 9.9 mm). Most of the variability can be attributed to tooth size. When normalized on the period, xmin and xmax are 0.28 (± 0.05) and 0.78 (± 0.05) on average, meaning that the Rousay sheep have recorded the minimum and maximum δ18O values on average at 78% and 28%, respectively, of the end of the periodic cycle recorded in the second molar.
... Stable isotope studies of tooth enamel have neglected all but some of the largest rodents; until the relatively recent advent of microlaser sampling (Sharp and Cerling 1998), most rodent teeth were too small to provide sufficient material for bulk analysis of carbon isotopes. The incisors of large rodents are highly suitable for serial sampling (Stuart- Williams and Schwarcz 1997), and the new microsampling techniques promise to increase the pool of species that can be investigated in this manner. ...
Article
Full-text available
Rodents are important components of most modern ecosystems. Understanding their roles in paleocommunities requires robust methods for inferring diet and other autecological characteristics. This pilot study tests whether a relationship between incisor morphology and diet exists among extant rodents that might be used to infer diets of extinct species. We focused on 11 genera of caviomorph rodents classified in 3 dietary categories: fruit—leaf, fruit—seed, and grass—leaf. For each genus 6 variables describing morphology of the upper incisor were measured on 5 specimens. Data were analyzed using a series of stepwise discriminant analyses. Discriminant analyses correctly predicted diets of nearly all training cases (∼95%) using 4 incisor characteristics. Five additional species (1 caviomorph and 4 noncaviomorph), treated as unknowns, also were classified correctly. Jackknife analyses correctly predicted diets of approximately two-thirds of training cases. Our study indicates that incisor morphology is related to diet in extant caviomorph rodents. Incisor data therefore might be useful for inferring diets of extinct species.
... The oxygen isotopic composition of a growing mammal tooth can vary with the changes of season and so provide a powerful seasonal marker to which to relate other compositional changes in the teeth. This approach has been applied to a suite of African herbivores ( Kohn et al., 1996), beavers (Stuart Williams and Schwarz, 1997), fossil bison (Fricke and O' Neil, 1996), modern ungulates ( Balasse et al., 2003;Sharp and Cerling, 1998;Wiedemann et al., 1999) and wombats ( Fraser et al., 2008). Enamel formation involves two distinct stages, secretion and maturation. ...
... Mammalian tooth enamel forms incrementally from the top to the base of the tooth crown, and these differences in oxygen isotopes were attributed to seasonal variation in climate recorded sequentially during tooth mineralization. Today, intra-tooth isotope (d 13 C, d 18 O, 87 Sr/ 86 Sr) variations have been documented in a number of modern mammals, including bovids (Higgins and MacFadden, 2004; Copeland et al., 2008), cervids (Britton et al., 2009; Chritz et al., 2009; Stevens et al., 2011), equids (Higgins and MacFadden, 2004; Wang et al., 2008), hippopotamids (Passey and Cerling, 2002), marsupials (Fraser et al., 2008), ovicaprids (Balasse and Ambrose, 2005; Blaise and Balasse, 2011 ), and rodents (Williams and Schwarcz, 1997). Because the sequence of tooth formation is ontogenetically constrained and varies according to species , this research provided the framework required to interpret the variations measured in archaeological and palaeontological specimens. ...
Article
Serial sampling and stable isotope analysis performed along the growth axis of vertebrate tooth enamel records differences attributed to seasonal variation in diet, climate or animal movement. Because several months are required to obtain mature enamel in large mammals, modifications in the isotopic composition of environmental parameters are not instantaneously recorded, and stable isotope analysis of tooth enamel returns a time-averaged signal attenuated in its amplitude relative to the input signal. For convenience, stable isotope profiles are usually determined on the side of the tooth where enamel is thickest. Here we investigate the possibility of improving the time resolution by targeting the side of the tooth where enamel is thinnest. Observation of developing third molars (M3) in sheep shows that the tooth growth rate is not constant but decreases exponentially, while the angle between the first layer of enamel deposited and the enamel–dentine junction increases as a tooth approaches its maximal length. We also noted differences in thickness and geometry of enamel growth between the mesial side (i.e., the side facing the M2) and the buccal side (i.e., the side facing the cheek) of the M3. Carbon and oxygen isotope variations were measured along the M3 teeth from eight sheep raised under controlled conditions. Intra-tooth variability was systematically larger along the mesial side and the difference in amplitude between the two sides was proportional to the time of exposure to the input signal. Although attenuated, the mesial side records variations in the environmental signal more faithfully than the buccal side. This approach can be adapted to other mammals whose teeth show lateral variation in enamel thickness and could potentially be used as an internal check for diagenesis.
... For C. canadensis, seasonal growth rates of the lower incisors have been documented and vary from 0.74 to 1.06 mm/day (Rinaldi and Cole 2004). A very similar growth rate of 0.75 mm/day was estimated by Stuart-Williams and Schwarcz (1997). Growth rates of upper and lower incisors do not necessarily correspond to each other on any given day (Rinaldi and Cole 2004:298). ...
Article
The first biplanar X-ray motion analysis of mastication and food processing for Castor fiber is presented. While particles are chipped off interaction of incisors involves variable movements of the lower mandible and thus incisors. After jaw opening the tip of the lower incisors can reach different positions anteriorly of the upper incisors. Then the mandible moves upwards and backwards and brings the tips of the incisors into contact. The lower incisors slide along the wear facet of the upper to the ledge when the cheek teeth occlude. The glenoid fossa and lower jaw condyle are in close contact during incisor contact and no transverse movements are observed. Mastication involves interaction of the cheek teeth with no contact of the incisors. When the cheek teeth are in occlusal contact the mandible is moved forward and transverse, or mediolateral. In consecutive power strokes the jaw is moved alternately to the right and left side. When the jaw opens it is brought into a more central but not totally centred position. During mastication the condyles are positioned posteriorly to the glenoid allowing lateral movement of the mandible. The lateral movement is particularly noticeable in the anterior part of the mandible. With the lateral movements of the incisors one glenoid has to move posteriorly, the other anteriorly.
... Body water has a higher measure of δ 18 O relative to rainwater as the body preferentially loses δ 16 O. Climate and water sources can also be distinguished , as δ 18 O values decrease with increasing latitude, altitude and distance from the coast as δ 18 O falls in precipitation (Williams and Schwarcz, 1997). The composition of mammalian oxygen isotope is dictated by body water. ...
Article
Maludong is a Terminal Pleistocene fossil-bearing cave located on the northern edge of the Southeast Asian tropical zone, southeastern Yunnan Province. Hominins from the cave include remains with affinities to archaic hominins and others with an apparent mixture of archaic and modern traits all deriving from deposits dating from the Bølling-Allerød interstadial. The sedimentary sequence of the cave appears to be largely anthropogenic in origin and records a nearly continuous record of fire lasting close to 1000 years. The fauna comprise only extant taxa and point to a rather biased sample with a preponderance of artiodactyls and carnivores, many of which show evidence for anthropogenic breakage and burning. A new analysis of the mammal fauna recovered during excavation, palaeohabitat reconstruction and stable isotope analysis of deer teeth and bones indicates the cave was located within or close to a closed forest environment. The mammal taxa also indicate a large body of water existed in the vicinity of Maludong, suggesting the modern lakes Datun Hai and Chang Qiao Hai were much larger at the time. Maludong may document an entirely novel ecological and behavioural scenario involving archaic and modern human interaction, economic exploitation and ceremonial behavior involving secondary burial practices.
... For C. canadensis, seasonal growth rates of the lower incisors have been documented and vary from 0.74 to 1.06 mm/day (Rinaldi and Cole 2004). A very similar growth rate of 0.75 mm/day was estimated by Stuart-Williams and Schwarcz (1997). Growth rates of upper and lower incisors do not necessarily correspond to each other on any given day (Rinaldi and Cole 2004:298). ...
Article
Beavers are known for their gnawing performance, e.g., felling trees. Even though this is well known, the biomechanics of it are not, and so this is the focus of this study. The lower incisors work as main cutting tools so that their technical parameters were studied. There are 3 angles (adding to 90°) of importance in cutting: (1) the wedge angle, the angle of the incisor tip; (2) the clearance angle between tooth and material (tree trunk); and (3) the chip angle between incisor tip and the perpendicular to the surface of the trunk. Cutting is usually oblique to the wood fibers. For technical wood cutting tools, an optimal wedge angle of 27° is known under certain conditions, and for the incisor of Castor fiber the wedge angle was determined using micro-Computed Tomography (µCT) scans to be 26.95°. Potential cutting forces of beavers were estimated for wood chips (2mm in thickness) of 3 sample tree species. For plum trees hardness forces ranged from 246 to 328N, and for maples from 190 to 254N. Finite element analyses were performed to determine stresses in the incisor under different loads on the incisor tip. Three hypotheses concerning gnawing were posed and are supported by the data: (1) The shape of the cutting blade of the incisor determines the geometry of wood chips and ultimately the maximum wood hardness that can be cut. (2) Clearance angle and maximum gape determine the maximum diameter of a tree that can be cut (if rough bark is neglected). (3) Functionally most importantly the lower incisors are optimized in shape and supporting tissue for compression stress with all forces being transmitted along the locations of the center of gravity in theoretical cross sections within the tooth, so that only compression occurs under load.
... In comparison with other osseous tissues, due to its high mineral content enamel is less susceptible, but not immune, to diagenetic alteration. The reliability of the isotopic signatures was examined by comparing values obtained from different osseous tissues and by using the trend of intra-tooth variations as well as the proportions of carbonate content (Wang and Cerling, 1994;Koch et al., 1997;Stuart-Williams and Schwarcz, 1997;Kohn et al., 1999;Lee-Thorp and Sponheimer, 2003;Zazzo et al., 2004;Tütken and Vennemann, 2011 (Table 3). A tendency towards more positive d 18 O for dentine and cementum in comparison with enamel has been observed for a larger sample from the same collection (cf. ...
... Moreover, water residence time in an animal's body increases with increasing body mass, thus affecting the resulting oxygen isotope composition of body water and apatite by further dampening the environmental seasonal signal. For example, Stuart-Williams and Schwarcz (1997) noted that a δ 18 O variance of ~4‰ in the incisors of the beavers from Ontario corresponds to the annual variance of > 10‰ in local precipitation. Other authors have used offsets within range of 0.5-9‰ for interpretation of climate seasonality. ...
Article
Stable isotopes of oxygen and carbon of tooth enamel are increasingly being used as tracers to study palaeoecology and the diet preferences of fossil vertebrates. We serially sampled tooth enamel carbonate along the growth axes of five Early Maastrichtian carnivorous dinosaur teeth (Tarbosaurus bataar tyrannosaurid) from the Nemegt Formation, Mongolia, in order to identify seasonal climatic variations and determine the diet of this apex predator. Additional bulk samples of dentine, bone, and surrounding sediment were analyzed in order to exclude diagenetic obfuscation of the isotopic record. Enamel samples of potential prey species for dietary studies were also analyzed. In the case of the largest specimens, the sampled teeth usually recorded annual cycles ranging between two-thirds and a full year. Fluctuations in δ18O values in tyrannosaurid teeth suggest seasonality (high annual temperatures with distinct precipitation/humidity maxima during summer months) with mean annual temperatures (MAT) ten degrees higher than those of present-day Mongolia. The seasonal pattern of δ18O shows similarities to that of the modern-day Shijiazhuang Global Network of Isotopes in Precipitation station, northern China, and suggests that the Nemegt biota flourished when exposed to a cool temperate monsoon-influenced climate. Herbivore and carnivore carbon isotopes (δ13C) values from tooth enamel imply the presence of a woodland ecosystem dominated by coniferous trees such as Araucariaceae, and are consistent with the hypothesis that large sauropods and hadrosaurids were the preferred prey of Tarbosaurus. Mean annual precipitation (MAP), based on the relationship between modern-day C3 gymnosperms and local average MAP, is estimated at 775–835 mm/yr. These results show that large theropod teeth can serve as valuable archives for palaeoenvironmental studies.
... This since mammals keep their body temperatures constant so that the oxygen isotopic composition of their enamel is not hugely affected by metabolic processes. Variations in δ 18 O values of consumed water, which are captured in enamel carbonates, reflect prevailing climatic conditions including temperature, precipitation and humidity (Longinelli, 1984;Ayliffe and Chivas, 1990;Kohn, 1996;Stuart-Williams and Schwarcz, 1997;Levin et al., 2006;Yann et al., 2013). Specifically, δ 18 O values of meteoric water, and hence also of enamel carbonates, increase under warmer, drier conditions (Fricke et al., 1995;Fricke and O'Neil, 1999;Fricke, 2003). ...
Article
This study investigates the mid-Pleistocene paleoenvironment and dietary behaviour of ancient herbivores in the South African central interior, today part of the semi-arid Kalahari savanna. Analyses were undertaken of carbon (δ¹³C) and oxygen (δ¹⁸O) stable isotopes in tooth enamel carbonate of twelve fossil herbivore species from Layers 4b and 4a, associated with Earlier Stone Age (ESA) and transitional ESA-Middle Stone Age (Fauresmith) industries respectively, at the archaeological site of Kathu Pan 1. The data are compared with other early to mid-Pleistocene herbivore assemblages located in the central interior, namely Cornelia-Uitzoek, Wonderwerk Cave and the Florisbad Spring. Results indicate that the median δ¹³C values for all ungulate taxa at Kathu were >-4‰, indicating predominantly C4 based diets, although in certain taxa, some individuals included a significant C3 component in their diet. The δ¹⁸O values of most of species at Kathu were relatively low, suggesting a cooler and/or wetter climate. Carbon isotope evidence for C4 dominated habitats at Kathu, but with a larger C3 component amongst grazers than today, resembles the other early to mid-Pleistocene assemblages in the region. Similarly, δ¹⁸O values for Kathu supplement existing evidence that the region was substantially wetter than in modern times.
... Thus, sequential sampling of bioapatite allows the reconstruction of detailed records of seasonal variations in diet and climate during the time period of tooth formation. This method has been used on ever-growing teeth, in this case tusks, to determine the season of death of proboscideans (El Adli et al., 2017;Fisher et al., 2003;Fisher and Fox, 2007;Koch et al., 1989;Stuart--Williams and Schwarcz, 1997). In order to extend it to ungulate teeth with definite growth periods, the method requires selecting young animals, for which the mineralisation process was still on-going at the time of their death. ...
Article
The assessment of the date of death (DOD) of animals found in archaeological sites provides insights into the exploitation of their environment by ancient mobile and sedentary populations. In an attempt to overcome the limitations of the traditional methods, we determine the DOD of domestic caprines using sequential oxygen isotope analysis of developing tooth enamel. We built a reference set composed of developing molars from 14 modern sheep and goats from Western and Central Mongolia with known DOD. The teeth were sequentially sampled, and δ¹⁸O sequences were modelled using a cosine function in order to position the lowermost δ¹⁸O value (δf) within the annual cycle. We found that δf values are strongly linearly correlated with the DOD (R² = 0.88), allowing the use of this regression to estimate the DOD with a precision of about ±25 d (1σ). This method was applied to determine the DOD of caprines found in two graves in the Xiongnu necropolis of Egiin Gol, Mongolia. We determined a slaughter date of late July and late September for the two graves, respectively, suggesting that burial occurred during the warm season. By combining this information with age at death assessed using tooth eruption stages and tooth wear patterns, we were also able to determine that caprine birth occurred mostly in April and was strongly controlled within this seasonal window by the herders, much like in Mongolia today.
... When the temperature is higher, there is more energy to keep both molecules in the air, but when the temperature is cold, the heavier molecules are preferentially removed and the remaining moisture becomes isotopically lighter. Thus, the oxygen isotope content of rainfall depends on climatic and environmental variables such as temperature, humidity, altitude, and distance from the sea where clouds form (Ayliffe and Chivas 1988;Stuart-Williams and Schwarcz 1997). Its light stable isotopes fractionate during the metabolic processes and are incorporated into the biological hard tissues. ...
Article
Full-text available
The original version of this article, unfortunately, contained errors. The original version of this article, unfortunately, contained errors. The corresponding author failed to notice that Professor Wu Xiaotong’s affiliation is incorrect. Wu Xiaotong should have been affiliated to “Shandong University” instead of “Jilin University. Given in this article is the corrected affiliation.
... The sequential sampling was carried out to gain information about seasonality and animal ecology. While a similar approach was previously used for estimates of seasonality (e.g., Fricke and O'Neil, 1996;Stuart-Williams and Schwarcz, 1997;Fricke et al., 1998;Kohn et al., 1998;Hoppe et al., 2004Hoppe et al., , 2005Makarewicz, 2017;Makarewicz and Pederzani, 2017), the complexity of tooth mineralization will necessarily time average the original isotope compositions and care has to be taken for the interpretations. Tooth enamel mineralization can be divided into two main stages: apposition (or secretion) and maturation (or mineralization) (Simmer et al., 2012). ...
Article
We describe the Late Pliocene paleoenvironment and paleoclimate of the Pula fossil site of the western Pannonian Basin, Hungary, which occurs within a lacustrine succession deposited in a volcanic crater (maar). Radiometric dating of adjacent volcanic bodies hosting the fossil-bearing sedimentary assemblages gives an age of 4.25 ± 0.17 Ma (K-Ar). To date, five, articulated rhinoceros skeletons (Dihoplus sp.) have been recovered, and a few fragmentary remains of artiodactyls and freshwater fishes (Perca sp., Leuciscus sp. and Gobius sp.) are also present. An insect taphocoenosis comprises terrestrial groups that inhabited the former lake margins (Syrphidae, Heteroptera, Chalcidoidea, Tenebrionidae) as well as aquatic insects (Dytiscidae, Baetidae, and Chironomidae). Deciduous broad-leaved, woody plants prevailed in and around the Pula locality (Quercus, Ulmus, Zelkova, Acer, Salicaceae) and are associated with some rare floral elements (Ginkgo, Sassafras) and Buxus. Deposition at the lake bottom seems to have taken place in oxygen-depleted layers, and taphonomic evidence indicates that fossil material underwent minimal (if any) weathering. δ13C values of one rhinoceros tooth suggest that this mammal consumed mixed C3 plants in a wooded environment. The climatic conditions inferred from the reconstructed vegetation and stable oxygen isotope data from the tooth enamel support a Cf-type climate (Köppen classification) with a mean annual temperature of 10 to 13 °C with some dry periods during the year. Pula is comparable to other maar fossil sites of Pliocene age such as Camp dels Ninots, Spain, and Hajnáčka I, Slovakia.
... When the temperature is higher, there is more energy to keep both molecules in the air, but when the temperature is cold, the heavier molecules are preferentially removed and the remaining moisture becomes isotopically lighter. Thus, the oxygen isotope content of rainfall depends on climatic and environmental variables such as temperature, humidity, altitude, and distance from the sea where clouds form (Ayliffe and Chivas 1988;Stuart-Williams and Schwarcz 1997). Its light stable isotopes fractionate during the metabolic processes and are incorporated into the biological hard tissues. ...
Article
Full-text available
Discussions on colonialism are pervasive in western scholarship but are hardly ever applied to the archeology of China. The present paper shows how concepts of colonialism and migration research can be successfully applied to understand Han imperial expansion into southwest China and how the Chinese material can in turn contribute to developing theories and methods of colonialism research further. Taking the Shamaoshan cemetery as a case study, the present paper combines archeological, textual, environmental, and isotope data to gain insights into strategies and processes of Han imperial expansion into southwest China. The insights gained here show that the long-accepted story-line of simple “Sinicization” and political control is far from accurate. Instead, it took over a century of cross-cultural exchange with immigrants and locals adopting each other’s customs to varying degrees. While in the beginning the Han seem to have taken a top-down approach to “civilizing” the region through their elites, the present study suggests that in the end it was the lower levels of society that intermingled most intensively and helped integrate migrants and locals successfully. Moving away from the exclusive focus on exceptional graves and large sites, the present study thus shows the great value of approaching small, poorly equipped graves with new methods, combining isotope research with a nuanced analysis of burial remains. Evaluated together with the evidence from the well-known exceptional graves, lesser-known settlement material, and historical accounts, the Shamaoshan case study has made it clear that various types of contact, colonial and otherwise, play out quite differently within different social groups and historical situations. This study thus proposes a multisource, multimethod approach that moves away from a narrative dominated by the history-writing elite segments of the colonizing force to a multivoiced account integrating local and outside perceptions at various social levels, an approach that might successfully be applied in other parts of the world.
... Oxigeno isotopoen erlazioa iraganeko eta gaur eguneko biztanleriaren jatorriari buruzko informazioa lortzeko baliagarria da [30][31][32]. Era berean diziplina ezberdinetako adituek, oxigeno isotopoak erabiltzen dituzte espezie desberdinetan paleoklima berreraikitzeko [33,34], animalien migrazio eta artzaintzaren ereduak ezagutzeko [35,36] eta animali eta landareen jatorri geografikoa jakiteko [38,39]. ...
Article
Full-text available
Gizakien hezur eta hortzetan neurtutako isotopo-erlazioak (87Sr/86Sr, δ13C, δ15N eta δ18O) antzinako gizakien elikadura eta mugikortasun ereduak berreraikitzeko erabiltzen dira. Gizakien elikaduraren berri izateko gizaki eta faunaren hezurretik lortutako kolagenoan karbono eta nitrogeno isotopoen analisiak egiten dira. Gainera, gizaki eta animalien mugikortasunari buruz informazioa lortzeko hezur eta hortzetan neurtutako estrontzio eta oxigenoen isotopo-erlazioak dira erabiliak. Isotopo hauek duten aplikazioa ikusteko Erdi Aroko hiru aztarnategiren emaitzak deskribatuko dira, Momoitioko San Juan (Bizkaia), Tauste (Zaragoza), eta Las Gobasekoak (Trebiñuko Konderria) hain zuzen ere.
... Enamel bioapatite oxygen isotopes are derived from body water, which is influenced by the oxygen isotopic composition of ingested water, atmospheric oxygen and organic compounds in foods (Bryant et al., 1996;Longinelli, 1984;Luz et al., 1984). Although the relative contribution of each source to body water varies depending on animal feeding and drinking behaviors, as well as energy expenditure (Bryant and Froelich, 1995;Levin et al., 2006;Luz et al., 1984), the d 18 O values of mineralized herbivore hard tissues primarily reflect the oxygen isotopic composition of isotopically diverse imbibed water sources including ground water, open water, and/or leaf waters (Bryant et al., 1996;Levin et al., 2006;Stuart-Williams and Schwarcz, 1997). ...
Article
Vertical transhumance is a crucial animal management strategy that provides livestock with fresh pasture on a seasonal basis while simultaneously expanding the scale of landscape usage by the pastoralist component of complex agro-pastoralist societies. Here, we explore the use of vertical transhumance in Anatolia during the Early and Middle Chalcolithic periods (6200–4500 cal BC), a time of socio-political transformation that presaged the rise of early state level societies in the region supported by a pronounced intensification in the exploitation of domesticated sheep and goats for their wool – a valuable commodity. We examine the carbon (δ¹³C) and oxygen (δ¹⁸O) composition of sequentially sampled tooth enamel from Chalcolithic sheep and goats from Köşk Höyük. The pattern of inverse cyclical isotopic variation characterized by high summer season δ¹⁸O values coincident with low δ¹³C values suggests livestock were moved to moist, high elevation pastures supporting ¹³C-depleted graze during the summer months or supplied with ¹³C-enriched fodder during the winter months. Inter-individual variation in absolute δ¹⁸O values and the amplitude of intra-tooth oxygen isotopic change reflects either differences in the spatial location of pastures, differences in the relative contribution of ¹⁸O enriched leaf water to caprine body water, or a combination of both. The incorporation of pasturing strategies involving vertical transhumance into livestock management systems, in conjunction with zooarchaeological evidence for increasing pastoral specialization and wool production at Köşk Höyük, suggests an intensification of smallstock production that provided important economic support for increasingly complex political landscapes.
Chapter
Stable isotope analysis is a well‐established tool for studying past human remains. Applications have grown exponentially in the past 15 years, with studies focusing on living human and nonhuman primates, other mammals and reconstruction of complex food webs. These related studies contribute to our understanding of results obtained from past human groups. Stable isotopes of carbon and nitrogen have been used to reconstruct past diet for many parts of the world. Research questions such as the timing of the introduction of maize agriculture, reliance on terrestrial, marine and freshwater resources and proportions of plant and animal foods in the diet have all been addressed. Stable isotopes have also been used to estimate the duration of nursing in past populations. This chapter provides information on the background, methods and applications of stable isotope analysis to research questions in biological anthropology.
Article
Full-text available
Using biogeochemical techniques based on 13C/12C and 18O/16O relationships in dental enamel, it was inferred if the diets of four Columbian mammoths (Mammuthus columbi) from Laguna de las Cruces (Salinas, San Luis Potosí, México) changed or were similar in time as a response to temperature variations. The results show that the diet of individual DP-1975 kept unchanged, whereas for mammoths DP-1976 and DP-1978 there was a small tendency for eating more C3 plants than C4 plants, possibly due to decreased temperatures, as shown by δ18O values. However, the isotopic carbon values of mammoth DP-1979 show that the specimen was first a mixed feeder C3/C4 and later ate mostly C4 plants, probably due to an increase in the temperature. Furthermore comparisons made between δ13C and δ18O values at the population level show that the two young mammoths, with 18 and 20 years old, are different from the two adults, which seem to be 43 and 47 years old respectively. Such differences may be due to different feed behaviors among young and adult, although it could also indicate that the individuals came from different areas.
Article
Almost two thousand mandibular teeth of the short-necked giraffid, Sivatherium hendeyi, from Lange-baanweg, South Africa, were examined for dental pathologies. Enamel hypoplasia is present in 0 to 34 percent of deciduous teeth and 40 to 75 percent of permanent teeth. No linear enamel hypoplasias were found in the deciduous teeth, while 20 to 35 percent of the permanent teeth have this defect. The linear defects at the base of the first molar are thought to relate to stress associated with weaning. The defects in the later erupting permanent teeth are, however, widely distributed over tooth crowns. Several linear defects are present on some teeth suggesting that these stress episodes were periodic. We propose that poor environmental conditions, possibly seasonal nutritional stress, are responsible for the observed enamel hypoplasia in the permanent dentition of S. hendeyi. This study provides new insight into the current understanding of the paleoenvironment at Langebaanweg, South Africa.
Article
While political integration can be achieved by many means, here we focus on the use of feasting and statecraft in the Inka Empire of the Andean Late Horizon (c. AD 1400–1532) in South America. In order to examine Inka political integration of the Lake Titicaca Basin of Bolivia, we examine paleomobility and paleodiet through radiogenic strontium and stable oxygen and carbon isotope data in archaeological camelid remains from the site of Tiwanaku. Mean radiogenic strontium isotope values from all archaeological camelid enamel and bone samples is 87Sr/86Sr = 0.70998 ± 0.00179 (1σ, n = 48), mean stable oxygen isotope values from a sub-set of archaeological camelid enamel and bone samples is δ18Ocarbonate (VPDB) = −10.0‰ ± 2.6‰ (1σ, n = 18) and mean stable carbon isotope values from a sub-set of archaeological camelid enamel and bone samples is δ13Ccarbonate (VPDB) = −9.0‰ ± 1.7‰ (1σ, n = 18). While many camelids consumed in these feasting events were likely local to the Lake Titicaca Basin, others came from a variety of different geologic zones, elucidating our understanding of Inka statecraft and the role of feasting in political integration in empires in the past.
Article
Oxygen isotopes (delta O-18) in animal and human tissues are expected to be good recorders of geographical origin and migration histories. However, seasonal variation of delta O-18 may diminish the origin information in the tissues. Here the seasonality of delta O-18 in tail hair was investigated in a domestic suckler cow (Bos taurus) that underwent different ambient conditions, physiological states, keeping and feeding during five years. A detailed mechanistic model was built to explain this variation. The measured delta O-18 in hair significantly related (p < 0.05) to the delta O-18 in meteoric water in a regression analysis. Modelling suggested that this relation was only partly derived from the direct influence of feed moisture. Ambient conditions (temperature, moisture) also affected the animal itself (drinking water demand, transcutaneous vapor etc.). The clear temporal variation thus resulted from complex interactions with multiple influences. The twofold influence of ambient conditions via the feed and via the animal itself is advantageous for tracing the geographic origin because delta O-18 is then less influenced by variations in moisture uptake; however, it is unfavorable for indicating the production system, e.g. to distinguish between milk produced from fresh grass or from silage. The model is versatile but needs testing under a wider range of conditions.
Article
The Osmore Drainage of southern Peru has a long and rich history of human occupation. While the utility of stable oxygen and radiogenic strontium isotope values in identifying paleomobility between this region and population centers in the Bolivian altiplano has been well established, many questions about intra-regional mobility remain. To better understand how these methods can be used to detect localized residential mobility, we present new δ¹⁸Omw(VSMOW) and ⁸⁷Sr/⁸⁶Sr values from water, soil, plant, and faunal samples. Samples were collected primarily from traditionally farmed agricultural fields in the upper, middle, and lower Osmore Drainage. Results are indiscernible between the upper and middle drainage, while marine contribution to the lower drainage produces distinct values. We discuss the methodological limitations and implications of our results for the use of stable oxygen and radiogenic strontium isotope analyses for intra-regional paleomobility studies in the Osmore Drainage.
Article
The carbon and oxygen isotopic compositions of the tooth enamel of mammals, including deer, wild pigs, buffaloes and domesticated pigs from the Shunshanji site, Sihong County, Jiangsu Province, China, were analyzed to reconstruct the mammals’ ecoenvironments and diets, and to evaluate seasonal variations in the study area. Carbon isotopic compositions of buck samples revealed that the deer ate completely C3 plants and the environments they inhabited were relatively open and that wild pigs ate primarily C3 plants. Oxygen isotopic compositions indicated that the body sources of these two mammals were different, i.e. the deer and pigs lived in different niches within a relatively similar ecosystem. Modern domesticated pigs were isotopically more positive than the ancient wild pigs in carbon δ 13C values, suggesting the former ingested more C3 plants relative to the latter. Although the δ 18O data showed modern domesticated and ancient pigs had similar oxygen isotope compositions, their water sources were different. The carbon and oxygen isotopic patterns of premolar microsamples of ancient and modern buffaloes indicated that the plants ingested by the ancient buffalo varied with seasonal shifts, but plants ingested by the modern buffalo were relatively constant. The eco-environment of the modern buffalo was more open, warmer and drier than eco-environment of the ancient buffalo, which may be the result of the deforestation and other human activities. Ancient and modern seasonal changes were clearly recorded in the isotopic patterns and the seasonal variation amplitudes of the ancient and modern eco-environments were similar.
Article
Stable carbon and oxygen isotope ratios of tooth enamel provide a means to examine nutritional changes during childhood. To date, such studies have used large enamel samples, often spanning the developmental period of the tooth. This paper reports the results of small samples drilled from first molars and premolars of human teeth from Kaminaljuyu, a Classic period city in highland Guatemala. Carbon isotopes show considerable increase between cuspal and cervical enamel for both teeth, indicating an increase in maize consumption during childhood. Oxygen isotope trends are more variable, and suggest some seasonal fluctuation. While the oxygen isotope data confirm the identification of foreign skeletons among the samples, they illustrate a need for caution when sampling teeth due to variable δ18O composition of enamel within a tooth.
Article
Full-text available
Using biogeochemical techniques based on 13C/12C and 18O/16O relationships in dental enamel, it was inferred if the diets of four Columbian mammoths (Mammuthus columbi) from Laguna de las Cruces (Salinas, San Luis Potosí, México) changed or were similar in time as a response to temperature variations. The results show that the diet of individual DP-1975 kept unchanged, whereas for mammoths DP-1976 and DP-1978 there was a small tendency for eating more C3 plants than C4 plants, possibly due to decreased temperatures, as shown by δ18O values. However, the isotopic carbon values of mammoth DP-1979 show that the specimen was first a mixed feeder C3/C4 and later ate mostly C4 plants, probably due to an increase in the temperature. Furthermore comparisons made between δ13C and δ18O values at the population level show that the two young mammoths, with 18 and 20 years old, are different from the two adults, which seem to be 43 and 47 years old respectively. Such differences may be due to different feed behaviors among young and adult, although it could also indicate that the individuals came from different areas.
Article
Human tissues including bone are constructed of molecules, some ingested heterotrophically, and some synthesized endogenously, under the control of the genome. The internal chemical environment (T, pH, solute activities, etc.) is maintained at a constant level (homeostasis) through compensatory processes, partly controlled by the endocrine system. Tissues that survive for subsequent geochemical analysis (bone, hair, skin) are largely composed of structural proteins (collagen, keratin). Bone is a composite material composed of collagen and a mineral (hydroxyapatite-like) which crystallizes from a supersaturated solution under the control of inhibitory molecules, mainly pyrophosphate. The structure of bone is hierarchical; μm-scale osteons are composed of nm-scale collagen fibrils and mineral crystals, all of which are continuously broken down by osteoclasts and regenerated by osteoblasts. Human diet provides energy mainly in the form of carbohydrates and lipids; energy is stored as endogenously produced lipids. Ingested proteins are hydrolyzed to amino acids, which may be used directly for protein synthesis (especially essential amino acids which cannot be biosynthesized) or may be used as fuel through gluconeogensis.
Article
Proboscidean tusks (hypertrophic incisors) are excellent sources of paleoecological data because they grow continuously by accretion. This allows for tracking of changes in morphology, stable isotope composition, and growth rate throughout an individual???s life. Tusks can provide evidence of sex, age, and season and cause of death, as well as the timing of life events (e.g., maturation). Here, analyses of tusk morphology, stable isotope composition (oxygen, carbon, and nitrogen), and growth increments are used to characterize the lives and circumstances surrounding the deaths of female American mastodons (Mammut americanum) from the latest Pleistocene in North America. Female mastodons are less common in the fossil record than males, but the recent discovery of an assemblage of female mastodons at the Bothwell Site in Indiana substantially increased the number of female mastodons available for study. Tusks from this new site, and other localities, are used to investigate mastodon sexual dimorphism, social structure, and life history. Chapter 2 presents an improved method for identifying the sex of a mastodon using only tusk measurements. Chapter 3 documents similarities in the character of African elephant (Loxodonta africana, Loxodonta cyclotis) and mastodon tusk dimorphism that can be used to infer similar social structures and behavior in Loxodonta and Mammut. Chapter 4 presents evidence that indicates multiple, temporally discrete mortality events led to formation of the female mastodon assemblage at Bothwell. Evidence from tusks suggests that the site represents a Paleoindian meat cache. Chapter 5 presents long-term tusk growth records for two female mastodons. Periodic variations in annual growth rate are proposed as evidence of pregnancy and lactation. The analyses presented here have value for interpreting other mastodon sites as well as for understanding how mastodons responded to climate change and human hunting, factors commonly cited as causal hypotheses for extinction. The results of this study do not provide support for a specific hypothesis, but evidence from growth increment and stable isotope analyses indicates that these mastodons did not experience nutritional stress at death. This suggests that, although the late Pleistocene environment was changing, environmental change did not unduly stress these mastodons.
Article
Vertical transhumance is an important animal husbandry strategy that provides livestock with consistent access to pasture throughout the year and contributed to the intensification of sheep and goat husbandry in the Near East over 10,000 years ago. Sequential carbon (δ¹³C) and oxygen (δ¹⁸O) isotope analyses of teeth from domesticated sheep and goats dating to the early Neolithic (9200 to 8700 cal yr B.P.) from a region of strong local topographic relief in southern Jordan exhibit inverse cyclical isotopic variation characterized by the coincidence of high δ¹⁸O values with low δ¹³C values indicating ingestion of ¹³C-depleted plants during the summer season. This pattern is consistent with vertical transhumance of caprines moving from low-elevation C3/C4 Irano-Turanian pastures to higher-elevation Mediterranean C3 pastures during the summer, but other seasonally directed animal husbandry strategies involving amendment of livestock diets generate a similar isotopic outcome. Caprine δ¹⁸O values referenced against the oxygen isotope ratios of contemporaneous obligate-drinking cattle and non-obligate-drinking mountain gazelle, species with limited home ranges, distinguish the influence of meteoric water, ¹⁸O-enriched leaf water, and movement on the oxygen isotopic composition of sheep and goat. This approach assists in independent validation of vertical transhumance hypothesized for cyclical variation in sequential δ¹³C and δ¹⁸O values and, also, decouples seasonal foddering from mobility in the carbon isotopic dietary record. The isotopic data presented here reveal that complex sheep and goat husbandry systems involving vertical transhumance, stationary flock-keeping, and winter foddering were in place by the ninth millennium cal year B.P. east of the Jordan Valley.
Article
Full-text available
This study addresses the political and military structure of early Teotihuacan through the analysis of oxygen-isotope ratios in skeletal phosphate from 41 victims of a sacrifice associated with the Feathered Serpent Pyramid. Oxygen-isotope ratios are markers of geographic identity. A comparison of bone and enamel values, which provides a contrast between environments experienced during growth and those of adulthood, illustrates that at least four different regions are represented in this sample. Those identified as soldiers had either lived locally since childhood or had moved to Teotihuacan from several foreign locations. Most had lived in Teotihuacan for a prolonged period before their death. This pattern suggests foreign 'recruitment' or mercenary behavior. The women had either lived all their lives in Teotihuacan or had moved from there to a foreign location. Most of the individuals in the center of the pyramid (burial 14) did not come from Teotihuacan, nor had they lived in the city long before their deaths. We suggest that the choice of victims was meant to demonstrate Teotihuacan's powerful ideology to the rest of the Mesoamerican world. Notably, this isotopic evidence of physical interaction between Teotihuacan and foreign regions considerably predates the currently existing archaeological evidence.
Research
Full-text available
This represents one of several sections of "A Bibliography Related to Crime Scene Interpretation with Emphases in Geotaphonomic and Forensic Archaeological Field Techniques, Nineteenth Edition" (The complete bibliography is also included at ResearchGate.net.). This is the most recent edition of a bibliography containing resources for multiple areas of crime scene, and particularly outdoor crime scene, investigations. It replaces the prior edition and contains approximately 10,000 additional citations. As an ongoing project, additional references, as encountered, will be added to future editions. Popular and scientific references to the use of stable isotopes in identifying skeletal remains; or, more accurately, identifying geographical ranges in which the decedent may have lived, are the focus of this section. It also includes topics such as Carbon 14 dating and bomb pulse data. Stable isotope analyses may provide investigators clues to the spatial history of unidentified victims. Our bones and teeth, throughout our lives become reservoirs for those chemical elements to which we are exposed. The longer those exposures to the varied concentrations of different elements in different areas of the world, the more likely the victim can be determined as having resided in a particular area. By knowing the areas inhabited by a victim, the more likely investigators will be able to track down his, or her, identity. Unlike radioactive isotopes, stable isotopes never disintegrate. Schwarz, (2007), provides a good example of the forensic value of stable isotopes: "Most of the O atoms in our body come from the water we drink, and is usually isotopically like the precipitation where we live. Therefore, we can often learn where a person lived from the isotopic composition of their teeth and bones. Fortunately, we now have maps showing the distribution of 18O/16O ratios in precipitation falling over North America and Europe which we can use to help trace the place of origin of a murder victim. Even burned remains can be analyzed this way." (Schwarz, 2007:28) Like DNA, stable isotope analyses will continue to be developed and be refined. And like DNA analyses, it may someday be a staple in the forensic scientist's toolbox. Because stable isotope analysis is so dependent on the proper collection of known environmental samples, the researcher is also referred to the section Geoarchaeology and Soil Science. Our culture obviously impacts and reflects where we live and what we consume. For those reasons, the researcher may find useful citations in the section entitled Criminal and Cultural Behavior. That said, crime scene investigators should also remember that other animal species and plant life associated with crime scenes, also reflect stable isotope signatures which may aid in reconstructing crime scene events. (2076 citations)
Article
High-resolution computed tomography (CT) scans through two fossilized lesions in hadrosaur bone guided paleohistological and stable-isotopic sampling to examine the stages and structures of bone repair in hadrosaurs. Two hadrosaur caudal neural spines from late Cretaceous bonebeds in Alberta, Canada, exhibit calluses produced during healing of traumatic fractures. In both CT scans and paleohistologic sections, these specimens display a combination of reptilian and non-reptilian characteristics in dinosaurian skeletal repairs. In one specimen the callus is dominated by a trabecular lattice that lacks signs of remodeling. Trabeculae in this callus are distinctively textured by clusters of densely packed, randomly oriented lacunae, two orders of magnitude larger than typical osteocyte lacunae and reminiscent of hypertrophic chondrocytes in cartilage of reptiles. The lattice represents early mineralization of callus tissue, and it preserves a δO value in mineral phosphate 0.6% lower than adjacent non-pathologic cortex, suggesting that the repair site was ~2.5°C warmer than uninjured tissue. The elevated temperature results from locally enhanced cellular activity around the fracture, a common consequence of bone injury in vertebrates. In the second specimen, the callus has been extensively remodeled, with several areas transformed to dense secondary Haversian bone typical of modern birds. Stable oxygen isotopes in bone phosphate of this callus show no isotopic offset, indicating that this injury had progressed further through the healing process before the animal's death. High-resolution CT scans reveal tissue density and structure differences between the two lesions, suggesting that this technology could eventually be used to gauge relative healing without altering unique fossil specimens.
Article
Full-text available
Centimetre-scale laminae in tusk and molar dentine of late Pleistocene mastodonts and mammoths have been interpreted as annual growth bands produced, in part, by seasonal variation in growth rate. To test this interpretation, we measured the oxygen isotope composition (δ18O) of the CO3 fraction of dentinal hydroxyapatite from samples covering consecutive inferred years of growth in tusks. In mammals, changes in the δ18O value of dental tissues within individuals predominantly reflect variation in the δ18O value of body fluids, which is controlled mainly by the isotopic composition of ingested water. In Northern Hemisphere continental regions, winter precipitation has substantially lower δ18O values than does precipitation in other seasons. If ingested water tracks focal precipitation, then seasonal variations in dentinal isotope composition should result, the lowest δ18O values representing winter growth. We demonstrate that there are substantial variations in the oxygen isotope composition of proboscidean dentinal apatite, and that isotopic identifications of winter (i.e., low δ18O values) coincide with those based on growth rate (i.e., slow-growth zones). Finally, the potential of oxygen isotope analyses of terrestrial mammals for assessing the seasonality of paleoclimates is considered.
Article
Full-text available
The δ18O of mammalian bone-phosphate varies linearly with δ18O of environmental water, but is not in isotopic equilibrium with that water. This situation is explained by a model of δ18O in body water in which the important fluxes of exchangeable oxygen through the body are taken into account. Fractionation of oxygen isotopes between body and environmental drinking water is dependent on the rates of drinking and respiration. Isotopic fractionation can be estimated from physiological data and the estimates correlate very well with observed fractionation. Species whose water consumption is large relatively to its energy expenditure is sensitive to isotopic ratio changes in environmental water.
Article
Full-text available
The major advantage of the oxygen in phosphate isotope paleothermometry is that it is a system which records temperatures with great sensitivity while bone (and teeth) building organisms are alive, and the record is nearly perfectly preserved after death. Fish from seven water bodies of different temperatures (3–23°C) and different δ18O (values −16 to +3) of the water were analysed. The δ18O values of the analysed PO4 vary from 6 to 25. The system passed the following tests: (a) the temperatures deduced from isotopic analyses of the sequence of fish from Lake Baikal are in good agreement with the temperatures measured in the thermally stratified lake; (b) the isotopic composition of fish bone phosphate is not influenced by the isotopic composition of the phosphate which is fed to the fish, but only by temperature and water composition.Isotopic analysis of fossil fish in combination with analysis of mammal bones should be a useful tool in deciphering continental paleoclimates.
Article
Article
Centimetre-scale laminae in tusk and molar dentine of late Pleistocene mastodonts and mammoths have been interpreted as annual growth bands produced, in part, by seasonal variation in growth rate. To test this interpretation, we measured the oxygen isotope composition (δ18O) of the CO3 fraction of dentinal hydroxyapatite from samples covering consecutive inferred years of growth in tusks. We demonstrate that there are substantial variations in the oxygen isotope composition of proboscidean dentinal apatite, and that isotopic identifications of winter (ie low δ18O values) coincide with those based on growth rate (ie slow-growth zones). Finally, the potential of oxygen isotope analyses of terrestrial mammals for assessing the seasonality of paleoclimates is considered. -from Authors
Article
The deuterium and oxygen isotopic compositions of precipitation from nine meteorological stations across Canada are discussed. It is documented that meteorological regimes determine isotope concentrations, with eastern Canada being dominated by 'tropical' and 'Atlantic' air streams whereas the west receives primarily Pacific storms. These patterns prevail during the summer, whereas during winter months, arctic air masses can arrive in vritually all areas of Canada. Relationships between ground T and isotope contents in precipitaion are presented and deuterium excess values are used to discuss secondary effects influencing isotope contents. The isotopic compositions of shallow groundwater closely reflect the average annual isotopic composition of local precipitation. Differences are explained by selective recharge (e.g. winter precipitation appears to be especially important in the Prairies) or recharge processes which have not totally smoothed out the input variations seen in precipitation. (Authors' abstract)-A.W.H. Dept. of Earth Sciences, Waterloo Univ., waterloo, Ontario, Canada. English
Article
The hydrogen isotopic ratio δD of rain is known to vary according to climate and temperature. The hydrogen in plant tissue reflects both δD of rain and daytime relative humidity (RH) during the growing season. Since tissue from a herbivorous animal records the δD value of the plants in their diets, δD of herbivore bone collagen should ultimately reflect growing season δD of rain, and to a lesser extent, RH. Therefore, the measurement of δD of non-migratory herbivore bone collagen could have considerable potential for monitoring changes in climate through time and thus prove to be a valuable paleoclimatic tool. In this study, methods for analyzing bone collagen for δD were tested and a means for correcting results for hydrogen exchange was devised. It was found that the δD of bone collagen of North American white tailed deer does indeed reflect both growing season rain δD and RH. With correction for the effects of RH the relationship of bone δD versus summer rain δD has a slope of 1.0 indicating a simple relationship and no unexplained sources of bias. It was also found that δ¹⁵N can be used to correct for the effects of RH so that bone δD can be used to estimate rain δD with good accuracy. The rain δD can then be used to estimate temperature. It was further found that relative humidity can be estimated using both bone collagen δD and bone phosphate δ¹⁸O. Additional work found that the δ¹⁵N of bone collagen of animals consuming some C₄ plants is related to local amount of precipitation whereas no such relationship exists for animals consuming only C₃ plants. δ¹⁵N and δ¹³C were also found to vary considerably across North America which could complicate their interpretation in paleodietary studies.
Article
A simple and precise method of determining the oxygen isotopic composition of Ag 3 PO 4 has been developed in which orthophosphate is condensed to pyrophosphate and higher polymeric forms at elevated temperatures using Br 2 as a reactant in a heated quartz vessel, releasing about 17.5% of the oxygen present as O 2 gas. The O 2 is converted to CO 2 using a heated carbon rod and analyzed using a mass spectrometer. The precision of the 18 O determination is better than 0.07 when reaction furnace temperature is regulated to within ±0.5°C. This method offers advantages of speed, safety, and cost over conventional BrF 5 decomposition of silver phosphate.
Article
Variation in the concentration of the stable isotopes of hydrogen, oxygen and carbon have been tested in continental records as tools for quantitative or semi-quantitative paleoclimatological studies. Among the different methods, the potential use of oxygen isotopes in mammal bone and tooth phosphate has recently been recognized. Measurements carried out on fossil mammal bones of Holocene age and their paleoclimatological interpretation corresponded well with paleontological and paleobotanical records. In the case of considerably older fossils, diagenetic processes may change the primary oxygen isotopic composition of phosphate. Fossil horse bones and teeth (principally of the species Equus stenonis) were studied to ascertain how far back in time fossil mammal remains may be considered reliable material for paleoclimatological studies. The samples come from 13 different locations in southeastern Spain, their age ranging from Maspinian (late Pleistocene) to Middle Villafranchian (Pliocene). Apart from the variations of the δ18O(PO43−) values which may be related to climatic changes, it is apparent that the isotopic composition of bones and teeth from the same deposit are frequently rather different from one another. The isotopic differences range from a few tenths of one % to several %. This suggests a strong influence of taphonomy over the measured isotopic values of fossils in each deposit. Time can be considered neither the only variable nor the most important one responsible for the change of the primary isotopic composition of fossils. Under these conditions it is rather difficult to establish lower or upper limits for the age of fossils to be studied for reliable paleoclimatological information since the limits are directly related to taphonomic history. This, in turn, is related to local environmental conditions and not only to the age of fossils.
Article
About eighty specimens from ten different species of mammals, collected from different areas under different climatic and environmental conditions, were measured for the oxygen isotopic composition of their bone and tooth phosphate. The equations relating these values to the mean oxygen isotopic composition of local meteoric water were also derived. The same equation can be used for goats, roe-bucks, and mouflons, despite the biological differences among these species. Measurements were made on about fourty different specimens of rabbit and hare from Europe, Africa, and Canada, but in this case the data obtained clearly show no direct relationship between the oxygen isotopic composition of local meteoric water and the isotopic composition of the skeletal phosphate. However, there seems to be an inverse relationship between the relative humidity of the studied areas and the delta(18)O(PO43-) of the skeletal phosphate, thus suggesting the use of fossil bones of these mammal species as recorders of palaeoenvironmental relative humidity. Finally, a new equation was derived for the isotopic scale for horses, on the basis of all the previous data and of a few newly obtained results
Article
Silver phosphate is precipitated from homogeneous solution by the volatilization of ammonia. Silver phosphate is soluble in ammoniacal solution because of the formation of the silver-ammonia complex. As ammonia escapes from the heated solution, large, easily filtered crystals of silver phosphate precipitate. The high gravimetric factor resulting from the use of silver ion as the precipitating agent makes a precise determination of phosphate possible.
Article
The oxygen-isotope data obtained from BiPO4 samples fluorinated in silver-soldered metal lines are systematically more negative than those obtained by fluorination in a line assembled with flareless fittings. Because of this the phosphate-water isotopic temperature scale has been revised by studying 27 samples of shells of living marine organisms from different areas. The slope of the calculated equation is practically identical to that of the carbonate equation.
Article
In chapter 2 the isotopic fractionation of water in some simple condensation-evaporation processes are considered quantitatively on the basis of the fractionation factors given in section 1.2. The condensation temperature is an important parameter, which has got some glaciological applications. The temperature effect (the δ's decreasing with temperature) together with varying evaporation and exchange appear in the “amount effect” as high δ's in sparse rain. The relative deuterium-oxygen-18 fractionation is not quite simple. If the relative deviations from the standard water (S.M.O.W.) are called δD and δ18, the best linear approximation is δD = 8 δ18.Chapter 3 gives some qualitative considerations on non-equilibrium (fast) processes. Kinetic effects have heavy bearings upon the effective fractionation factors. Such effects have only been demonstrated clearly in evaporation processes, but may also influence condensation processes. The quantity d = δD −8 δ18 is used as an index for non-equilibrium conditions.The stable isotope data from the world wide I.A.E.A.-W.M.O. precipitation survey are discussed in chapter 4. The unweighted mean annual composition of rain at tropical island stations fits the line δD = 4.6 δ18 indicating a first stage equilibrium condensation from vapour evaporated in a non-equilibrium process. Regional characteristics appear in the weighted means.The Northern hemisphere continental stations, except African and Near East, fit the line δD = 8.0 δ18 + 10 as far as the weighted means are concerned (δD = 8.1 δ18 + 11 for the unweighted) corresponding to an equilibrium Rayleigh condensation from vapour, evaporated in a non-equilibrium process from S.M.O.W. The departure from equilibrium vapour seems even higher in the rest of the investigated part of the world.At most stations the δD and varies linearily with δ18 with a slope close to 8, only at two stations higher than 8, at several lower than 8 (mainly connected with relatively dry climates).Considerable variations in the isotopic composition of monthly precipitation occur at most stations. At low latitudes the amount effect accounts for the variations, whereas seasonal variation at high latitudes is ascribed to the temperature effect. Tokyo is an example of a mid latitude station influenced by both effects.Some possible hydrological applications are outlined in chapter 5.
Article
The vapor pressure difference between H2 18O and H2 16O is the reason for the accumulation of the heavy molecule in transpiring leaves. Since photosynthesis on land is the main source of atmospheric oxygen, this mechanism is important for the remarkable enrichment of18O in atmospheric O2 (Dole effect). Using a simple box model for transpiring leaves a quantitative understanding of the isotope fractionation is possible which is well confirmed by the results of model experiments as well as by measurements on trees. Maximum enrichment of H2 18O in the water of leaves (relative to soil water) is 25 (theoretically, for dry air) and was found under natural conditions to be 21 (for 28 % relative humidity); minimum theoretical enrichment is zero (observed 2.5 ).
Article
Fossil elephant remains from sediments of Plio-Pleistocene age in the vicinity of Lake Turkana, Kenya, provide insights into the ability of the phosphate-oxygen system to preserve original δ18O values (δ18Op) in the depositional environment. Individual fossil specimens exhibit systematic variations in the δ18Op values of their various tooth and bone components. Differences in δ18Op values between these skeletal components can be as high as 3.6%., despite the fact that equivalent phases for individual modern elephants have δ18Op values which vary by less than 0.6%..XRD traces of the different skeletal phases of modern and fossil samples, also infer differential preservation of primary apatite crystallinities among the various fossil phases. Fossil samples of dentine, cementum and bone have X-ray spectra with sharper and more intense peaks compared to their modern counterparts, but little change in crystallinity is observed for fossil enamel samples. A model based on the premise that the enamel phase preserves primary isotope signatures and that the accompanying skeletal phases are partially re-equilibrated with the fluids associated with the microbial decomposition of the elephant's carcass is consistent with the features of the 18Op dataset.This isotopic evidence, in conjunction with the physical and chemical attributes of enamel, has led us to postulate that enamel could be preserving primary isotope signatures while other skeletal components are affected to varying degrees by alteration processes in the burial environment.
Article
The hydrogen isotopic ratio of bone collagen (δDb) and the oxygen isotopic ratio of bone phosphate (δ18Ob) from North American white-tailed deer are each related to both the isotopic ratio of local rain and relative humidity during the growing season. The humidity corrected bone δDb and δ18Ob are highly correlated with each other with a correlation coefficient of 0.962. The regression slope of this equation (8.0) reflects the δD vs. δ18O slope of meteoric water when we use a model which assumes that bone oxygen derives from leaf water rather than from drinking or environmental water. Therefore, growing season rain is the likely source of bone H and O.The effects of humidity are significantly greater for δ18Ob than for δDb. Relative humidity (RH) can be estimated with moderate accuracy (± 6%) from a combination of bone phosphate δ 18Ob and collagen δDb and δ15Nb. This indicates some potential benefits of using fossil bone for evaluating palaeohumidity. The estimate of RH improves to ± 4% when only data from warm climate areas are considered. It appears that for cold climate areas of North America, there may be a discrepancy between the actual leaf water values and the leaf water isotopic values predicted on the basis of the leaf water models used here. It seems possible that the further study of bone isotopic values may lead to a better understanding of how the average leaf water values of an area are related to local environment.
Article
An analytical procedure is presented for the determination of the ratio in orthophosphate and condensed phosphate. In the described procedure the phosphate is first purified, and then finally precipitated as BiPO4. The phosphate oxygen is released by the following reaction; then it is purified and analysed mass spectrometrically: BiP04(s) + 8/3 BrF3(l) → BiF3(s) + PF5(g) + 4/3 Br2(g) + 2 O2(g) The method is quantitative, free from isotopic fractionation and exchange, and precise to ±0.15‰. A correction can be made for the contaminating effect of water oxygen introduced during the hydrolysis of the condensed phosphates.The possibilities are given for the use of this procedure in the measurement of paleotemperatures.
Article
A model is proposed for oxygen isotope fractionation in body water of terrestrial, herbivorous mammals larger than 1 kg. The goal of this model is to estimate the oxygen isotopic composition (δ 18O) of intake water in order to reconstruct paleoclimate from the δ 18O of fossil biogenic phosphate. The principal oxygen inputs are liquid water, atmospheric O2, and oxygen in food. The principal outputs are water (liquid and vapor) and CO2. Body mass-dependent scaling equations are used to assign O2, H2O, and CO2 fluxes. The model predicts that the δ 18O of body water is higher than the δ 18O of intake water and approaches the δ18O of intake water with increasing body size, as observed in empirical data. This reflects the increasing importance of liquid water flux relative to atmospheric O2, CO2, and water vapor flux at larger size (i.e., water flux increases relatively faster than metabolic rate and surface area with increasing body size). These results suggest that the largest fossil taxa should be used for paleoclimate reconstruction because (1) potential errors are smallest at large body sizes and (2) drinking water forms a larger proportion of the oxygen intake. Paleoclimate reconstruction based on the δ 18O of biogenic phosphates can thus be corrected for body-mass fractionation effects, a significant cause of previously uncharacterized interspecific variation.
Article
Phosphate δ18O values (δ18Op) of modern elephant bone and teeth are found to vary linearly according to the δ18O of local meteoric water (δ18Omw), a parameter with close ties to regional and local climatic conditions. Enamel, dentine, cementum and bone separates from individual fossil elephant specimens, of Late Pleistocene age, have δOp values which vary by up to elephant specimens. The larger spread in the δ18Op values of the various skeletal phases for the fossil samples is interpreted as evidence for post-depositional alterantion of primary δ18Op signatures of some, if not all, of these fossil skeletal components.In the fossil samples investigated, enamel and dentine phases have systematically lower δ18O values than associated bone and cementum phases. Differential re-equilibration with soil waters, either by the wholesale replacement of primary apatite or by processes of isotopic exchange, is suggested as a mechanism to account for the observed spread in the fossil phosphate δ18O data.
Article
The potential use of oxygen isotopes in mammal bone phosphate to study paleoclimates has been recognized since a few years. It has been proven that the δ18O(PO43−) of some mammal species is related to the mean δ18O of local meteoric water, each species showing a specific linear relationship. We report here some measurements of the oxygen isotopic composition of bone phosphate from living specimens of deer, mice, cattle and sheep coming from different areas with different mean annual values of local meteoric water. The oxygen isotopic composition of body water (blood water) of some of these specimens has also been measured. Linear relationships between the δ18O of bone phosphate, the δ18O of blood water and the mean δ18O of local meteoric water have been found, as in the case of the previously studied specimens of humans, pigs and rats. The slopes of the calculated equations for the bone phosphate-meteoric water relationships are the following: 0.79 (wood mice), 1.01 (cattle), 1.13 (deer) and 1.48 (sheep). The calculated phosphate-water fractionation factors are quite homogeneous, ranging from 1.0172 to 1.0175. These values are very close to those which may be calculated for isotopic equilibrium conditions between bone phosphate and body water. Fossil bones from the studied species may now be used for paleoclimatological and paleohydrological studies.
Article
An investigation of Illinoian- and Sangamonian-age deposits in the type region for both Pleistocene stages in central Illinois has yielded a palynological record spanning the Illinoian-Sangamonian boundary associated with an interglacial fauna containing Geochelone crassiscutata. The pollen indicates a shift from high Picea and Pinus to deciduous trees, followed by grass and herbaceous taxa, and finally, a return of deciduous trees. This sequence appears to correlate with marine isotopic stages 6 through 5d. Faunal remains are abundant throughout but megafauna are present only in the interglacial section where Geochelone occurs. The presence of Geochelone suggests above-freezing temperatures in central Ilinois throughout the year during at least the portion of the Sangamonian represented.
Article
δ18O determinations of bone phosphate (δ18Op) have been performed on a suite of modern kangaroos and wallabies (known collectively as Macropods) that come from a wide variety of climatic zones within Australia. Macropod δ18Op values range from 16 to over 30%. (V-SMOW) and are found to correlate with environmental relative humidities. As Macropods are herbivorous mammals with low drinking water requirements that consume large amounts of plant leaf water, it is likely that the δ18Op signature of Macropods is reflecting leaf water fractionation processes that are controlled by relative humidity. These results indicate that δ18Op from fossil bones of Macropods and similar drought-tolerant herbivorous mammals may yield palaeohumidity estimates.
Article
Significant differences in the δ18Op value between teeth, and even within a single tooth were observed in a detailed study of the oxygen isotope composition of tooth enamel phosphate (δ18Op) of hypsodont teeth from bison and sheep jaws. The permanent molars and premolars of a fossil adult bison from eastern Wyoming (∼500 yr B.P.) and a modern sheep from California were analyzed. The bison is assumed to have been free-ranging with a variety of possible water sources, whereas the sheep was raised on a ranch. Inter-tooth variability in δ18Op for the bison compared to the sheep (5.6‰ and 3.5‰, respectively) may be a result of behavioral differences. Analyses of multiple samples from the m3 of both the bison and sheep vary to a similar degree (3.5‰) in a similar cyclic pattern down the length of the tooth, a pattern which is interpreted to be seasonal. When present, inter- and intra-tooth variations in δ18Op are controlled by the water and food ingested by the mammals during the period of enamel formation. In these localities, well waters, surface waters, and mother's milk have different isotopic compositions at different times of the year.The data underscore the role of biology and behavior in determining δ18Op values, and the need to understand how they vary for a population of interest. If these variations are taken into account, the δ18Op values of single samples from small, late-forming teeth (e.g. premolars) can be used as a proxy for the δ18O value of local meteoric water for long-term climate studies. Multiple samples from a single third molar may provide information on the duration and timing of enamel growth, seasonality, as well as long-term climate change.
Article
Oxygen isotope analyses of water in blood of humans and domestic pigs indicate that the oxygen isotope fractionation effects between ingested water and body water are the same in all specimens of the same species. The δ18O of body water has been shown to vary linearly with the mean δ18O of local meteoric water. This conclusion also holds for the bone phosphate. Thus, δ18O(PO3−4) values of unaltered fossil bones from humans and domestic pigs can be used to reconstruct the δ18O values of local meteoric waters during the life-times of the mammals. Such data can be used for paleohydrological and paleoclimatological studies both on land and at sea.
Article
Variations of δ18O of bone phosphate (δp) of white tailed deer were studied in samples with wide geographic distribution in North America. Bones from the same locality have similar isotopic values, and the difference between specimens (0.4‰) is not large relative to the measurement error (0.3‰). The total range of δp values is about 12‰. This indicates that deer use water from a relatively small area, and thus their δp indicates local environmental conditions. Multiple regression analysis between oxygen isotope composition of deer bone phosphate and of local relative humidity and precipitation (δw) yields a high correlation coefficient (0.95). This correlation is significantly better than the linear correlation (0.81) between δp and δw of precipitation alone. Thus δp depends on both isotopic composition of precipitation and on relative humidity. This is because deer obtain most of their water from leaves, the isotopic composition of which is partly controlled by relative humidity through evaporation/transpiration.
Article
Oxygen isotopic, elemental, and X-ray data are presented for a suite of 24 fossil horse teeth from Nebraska ranging in age from 18.2 to 8.5 Ma, to test the use of δ18O of enamel phosphate (δ18OP04) as a quantitative record of continental climate. Modern equid teeth were analyzed to estimate a relationship between δ8OP04 and environment water. Multiple samples of seven different fossil species from Burge Quarry, a ∼ 12 Ma attritional fossil deposit, indicate the diagenetic overprints exist but can be detected by decreased P concentration and increased crystallinity relative to modern enamel. Isotopic variation for the pristine samples from Burge Quarry is ±1.5% (1σ, n=9), which may represent the resolution of the procedure within a stratigraphic horizon. There are no apparent correlations with body size, hypsodonty, or phylogeny. A range of 7%0 in δ18OP04 occurs over the 10 m.y. interval. A trend towards depleted δ18OP04 of about 4% corresponds to a depletion of up to 6%0 in δ18O of precipitation between 18.2 and 8.5 Ma, but the range of variation of Burge is large relative to the climate signal. Our results demonstrate that δ18OP04 should be useful in quantitatively reconstructing Cenozoic continental paleoclimate on 106-year timescales. Isotopic variation due to taphonomic bias and the terrestrial rock record will likely obscure higher-order climate signals.
Article
The variations of the D/H and 18O/16O ratios of nonexchangeable hydrogen and oxygen in plant cellulose reveal systematic differences between terrestrial plant groups. The slope of δD versus δ18O of cellulose from a variety of aquatic plants is close to 8 (the meteoric water value), while the slope for a number of terrestrial species is greater than or equal to about 24. Two models involving incorporation of CO2 and H2O into cellulose precursors are proposed to account for these differences. Effects of evaporative transpiration on the isotopic composition of water in leaves are measured and discussed in the context of these models.
Oxygen isoto-pic environmental information showing possible seasonal varia-tion in large rodent incisors Oxygen isoto-pic analysis of silver orthophosphate using a reaction with bro-mine
  • H Stuart-Williams
  • Q Le
  • H P Schwarcz
Stuart-Williams H. Le Q. and Schwarcz H. P. (1993) Oxygen isoto-pic environmental information showing possible seasonal varia-tion in large rodent incisors. GSA Abstr. Annual Meeting. Stuart-Williams H. Le Q. and Schwarcz H. P. (1995) Oxygen isoto-pic analysis of silver orthophosphate using a reaction with bro-mine. Geochim. Cosmochim. Acta 58, 3837-3841.
A new method for purifying biogenic phosphates for oxygen isotopic analysis
  • H Stuart-Williams
  • Q Le
  • H P Schwarcz
Stuart-Williams H. Le Q. and Schwarcz H. P. (1997) A new method for purifying biogenic phosphates for oxygen isotopic analysis. (in prep.).
Environmental isotope data No. 7: World survey of isotope concentration in precipitation (1976-1979) Technical reports series no. 226 Geochelone in Illinois and the Illinoian-Sangamonian vegetation of the type region
  • Intl
Intl. Atomic Energy Agency. IAEA (1983) Environmental isotope data No. 7: World survey of isotope concentration in precipitation (1976-1979). Technical reports series no. 226. Intl. Atomic Energy Agency. King J. E. and Saunders J. J. (1986) Geochelone in Illinois and the Illinoian-Sangamonian vegetation of the type region. Quat. Res. 25, 89-99.
Dating the Sangamon interglacial near the type locality: Electron spin resonance (ESR) dating mammal teeth and gar scales from Hopwood Farm
  • B Blackwell
  • J J Saunders
  • N Woodman
  • B B Curry
  • H P Schwarcz
Blackwell B., Saunders J.J., Woodman N., Curry B.B., and Schwarcz H. P. ( 1997 ) Dating the Sangamon interglacial near the type locality: Electron spin resonance (ESR) dating mammal teeth and gar scales from Hopwood Farm, southern Illinois. (in press).
The isotopic composition of precipitation and groundwater in Canada In Isotope techniques in water resources development Oxygen isotope variations of phosphate in mam-malian bone and tooth enamel
  • Fritz P Drimmie
  • R J Frape
  • O K Shea
Fritz P., Drimmie R. J., Frape S. K., and O'Shea K. (1987) The isotopic composition of precipitation and groundwater in Canada. In Isotope techniques in water resources development; Proc. Ser., 539-550. Intl. Atomic Energy Agency. Huertas A. D., Iacumin P., Stenni B., S~inchez Chill6n B., and Longi-nelli A. ( 1995 ) Oxygen isotope variations of phosphate in mam-malian bone and tooth enamel. Geochim. Cosmochim. Acta 59, 4299-4305.
Environmental isotope data No. 1: World survey of isotope concentration in precipitation (1953-1963). Technical reports series no. 96
IAEA (1969) Environmental isotope data No. 1: World survey of isotope concentration in precipitation (1953-1963). Technical reports series no. 96. Intl. Atomic Energy Agency.
A bestiary for Pleistocene biologists
  • Martin
Martin P.S. and Guilday J. E. (1967) A bestiary for Pleistocene biologists. In Pleistocene Extinction: The Search for a Cause (ed. P. S. Martin and H. E. Wright);
Stable carbon and oxygen isotopes of natural waters in the Netherlands
  • Mook
Mook W. G. (1970) Stable carbon and oxygen isotopes of natural waters in the Netherlands. In Isotope Hydrology 1970; Proc. Symp. Vienna, 1970, 163-189. Intl. Atomic Energy Agency.
All isotopic analyses are quoted as permil VSMOW
  • A Appendix
Appendix A. Sample identification and isotopic analyses. All isotopic analyses are quoted as permil VSMOW.
Further thoughts on the impact of beaver on temperate landscapes
  • Coles
Coles B. (1992) Further thoughts on the impact of beaver on temperate landscapes. In Alluvial Archaeology in Britain (ed. S. Needham and M. G. Macklin), pp. 93-99. Oxbow Books.
Oxygen isotopic environmental information showing possible seasonal variation in large rodent incisors
  • H Stuart-Williams
  • Q Le
  • H P Schwarcz
Stuart-Williams H. Le Q. and Schwarcz H. P. (1993) Oxygen isotopic environmental information showing possible seasonal variation in large rodent incisors. GSA Abstr. Annual Meeting.
World survey of isotope concentration in precipitation (1976-1979). Technical reports series no. 226
IAEA (1983) Environmental isotope data No. 7: World survey of isotope concentration in precipitation (1976-1979). Technical reports series no. 226. Intl. Atomic Energy Agency.
Oxygen isotopic environmental information showing possible seasonal variation in large rodent incisors
  • Stuart-Williams