Article

What do stable isotopes tell us about hominid dietary and ecological niches in the Pliocene?

Article

What do stable isotopes tell us about hominid dietary and ecological niches in the Pliocene?

If you want to read the PDF, try requesting it from the authors.

Abstract

By now a reasonable set of carbon and oxygen isotope data from tooth enamel has been accumulated for South African Plio-Pleistocene hominids and associated fauna. Almost all individuals measured, independent of species and importantly, environment, show significant C-4 dietary inputs with some individuals showing very substantial C-4 inputs. This implies interactions with grassy environments for a period of well over a million years, a period that saw environments in southern Africa shift from closed woodlands to more open, grassy landscapes. Carbon isotope analysis alone is unable to permit the important distinction between direct consumption of grasses, or indirect consumption via grass-eating animals, such as small vertebrates and invertebrates. Other chemical tools provide ambiguous results. For instance, hominid strontium'/calcium distributions are equally plausible. Relatively low oxygen isotope values for all hominids in comparison to associated fauna show similarities with suids, monkeys and carnivores, but the causes of these similarities are as yet poorly understood. On present evidence hominid interaction with grassland foods is secure although their exact nature remains elusive.

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.

... Whereas summarizing this literature is beyond the scope of this article, I do refer to human-based studies when examples for nonhuman primates are lacking. A number of excellent recent reviews cover the fundamentals of isotope biogeochemistry in plants (Barbour 2007; Handley et al. 1999; Heaton 1999; Kohn 2010;) and animals (Gannes et al. 1998; Koch 2007; Kohn and Cerling 2002; Lee-Thorp et al. 2003; Martínez del Rio et al. 2009; Schoeninger 2010; Sponheimer et al. 2009). I refer readers to these sources for a more in-depth discussion of the material presented here. ...
... These ratios are predicted to vary as a function of habitat, physiology, and dietary proclivity (Koch 2007; Schoeninger 2010). Accordingly, stable isotopes have been used to investigate foraging ecology and niche partitioning among both living and extinct nonhuman primates (Codron et al. 2006; Crowley et al. 2011a; Dammhahn and Kappeler 2010; Fourie et al. 2008; Lee-Thorp et al. 2003; Loudon et al. 2007; Schoeninger et al. 1997). Stable isotope ratios are ideal for these purposes because the difference in mass between isotopes of an element is measurable. ...
... This combination of isotopes may also be useful for distinguishing consumption of hemiparasitic parasites, such as mistletoes from the family Loranthaceae, which tend to have lower δ 13 C, δ 15 N, and δ 18 O values than their host plants (Cernusak et al. 2004; Schulze et al. 1991). Because leaf δ 18 O is increased during evapotranspiration, oxygen isotope values may also be able to discriminate, folivores, frugivores, and root-consuming animals (Carter 2001; Cerling et al. 2004; Lee-Thorp et al. 2003). ...
Article
Full-text available
Stable isotope biogeochemistry is useful for quantifying the feeding ecology of modern and extinct primates. Over the past three decades, substantial advances have been made in our knowledge of the physiological causes of isotopic patterns as well as effective methodology to prepare samples for isotopic analysis. Despite these advances, the potential of stable isotope biogeochemistry has yet to be fully exploited by primate researchers, perhaps due to the prolific and somewhat daunting nature of the isotopic literature. I here aim to present a cogent overview of stable isotope applications to nonhuman primate feeding ecology. I review the factors that influence ecological patterns in carbon, nitrogen, and oxygen stable isotopes. I present methods for collecting and preparing samples of tooth enamel and bone mineral hydroxyapatite, bone collagen, fur and hair keratin, blood, feces, and urine for isotope analysis. I discuss both the existing and potential applications of these isotopic patterns to primate feeding ecology. Lastly, I point out some of the pitfalls to avoid when interpreting and comparing isotopic results.
... The relative concentration of strontium to calcium (Sr/ Ca) in mammalian bioapatite has proven to be an effective indicator of trophic level, dietary behavior, and habitat use in both modern and ancient ecosystems (Elias et al., 1982;Sillen, 1986;Sealy and Sillen, 1988;Sillen et al., 1992;Gilbert et al., 1994;Burton et al., 1999;Blum et al., 2000;Balter et al., 2002;Palmqvist et al., 2003;Lee-Thorp et al., 2003;Balter, 2004;Sponheimer et al., 2005;Sponheimer and Lee-Thorp, 2006;Domingo et al., 2012;Peek and Clementz, 2012;Qu et al., 2013;de Winter et al., 2016). Strontium is a non-essential trace element, which mammals discriminate against relative to Ca in their intestines, kidneys, sites of bioapatite formation, and across the placenta and mammary glands (Taylor et al., 1962;Lengemann, 1963;Walser and Robinson, 1963;Underwood, 1977;Sasaki and Garant, 1986;Avioli, 1988;Rossipal et al., 2000;Chattopadhyay et al., 2007). ...
... Sr and Ca data are presented here as ratios multiplied by 1000 (e g. Sr/Ca x 1000) (Sillen 1992;Balter et al., 2002;Palmqvist et al., 2003;Lee-Thorp et al., 2003;Sponheimer et al., 2005;Spomheimer and Lee-Thorp, 2006;Domingo et al., 2009Domingo et al., , 2012. Sr/Ca ratios were compared among taxa using both parametric (ANOVA, Fisher's LSD) and non-parametric (Kruskal-Wallis) tests where appropriate. ...
... The Sr/Ca ratios of the R. II fauna (Table 1; Fig. 1; Table I in the Appendix) are comparable with those reported for both modern (Elias et al., 1982;Gilbert et al., 1994;Burton et al., 1999;Peek and Clementz, 2012;Martin et al., 2015) and fossil mammals (Balter et al., 2002(Balter et al., , 2012Lee-Thorp et al., 2003;Palmqvist et al., 2003;Sponheimer et al., 2005;Sponheimer and Lee-Thorp, 2006;Domingo et al., 2012). Statistically significant differences in Sr/Ca ratios among taxa ( Table 2) indicates that diagenesis has not obscured the original ecological signal. ...
Article
The early Late Miocene vertebrate locality of Rudabánya II (R. II) in northeastern Hungary preserves an abundance of forest-adapted ungulate species. To better understand the ecological relationships within this ancient ecosystem, we used analysis of enamel strontium/calcium (Sr/Ca) ratios to infer dietary preferences. The goals of the analysis were to: i) determine whether these ungulate species specialized in specific plants or plant parts; ii) discern whether the Sr/Ca ratios support what was previously suggested about the ecology of these species and iii) evaluate the factors that may have acted to promote coexistence within this diverse community of predominantly browsing herbivores. Results show significant differences in the diets of the sampled species. The highest Sr/Ca ratios were displayed by the suids Parachleuastochoerus kretzoii (fortelius et al., 2005) and Propotamochoerus palaeochoerus (pilgrim, 1926) implying a preference for Sr-rich underground plant parts. Elevated Sr/Ca ratios yielded by the cervid Lucentia aff. pierensis (thomas, 1951) and equid Hippotherium intrans (kretzoi, 1983) are indicative of intermediate feeding. The bovid Miotragocerus sp. (stromer, 1928) showed higher Sr/Ca ratios than the gomphothere Tetralophodon longirostris (kaup, 1832), which is incongruent with morphological and stable isotope data, and suggested browsing by both taxa. This finding is likely the result of a difference in digestive physiology (ruminant vs. monogastric) rather than a difference in dietary behaviour. The lowest Sr/Ca ratios were displayed by the traguild Dorcatherium naui (kaup and scholl, 1834) and moschid Micromeryx flourensianus (lartet, 1851) suggesting a preference for Sr-poor fruits. Resource specialization and partitioning within the local environment likely acted to decrease interspecific competition and promote coexistence within the diverse ungulate community at R. II.
... Indeed, modern African apes are restricted to forested environments, and savanna environments require special skills for exploitation by primates, such as a bipedal gait and strong social bonds. The d 13 C values of tooth enamel of fossil mammals, including hominids, from South Africa, ranging in age from 1.8 to 1.5 million years old, indicate a significant C 4 component in the environment, as well as significant C 4 dietary inputs for hominids of the species Paranthropus robustus, and Homo ergaster (Figure 7; Lee- Thorp et al., 2000Thorp et al., , 2003Thorp et al., , 2010. This C 4 dietary input could be linked to the consumption of C 4 plant parts, but also to the consumption of animals feeding on C 4 plants, such as invertebrates, small vertebrates, or grazer meat. ...
... Reconstruction of the paleoenvironment and paleodiet of fossil hominids from South Africa (Swartkrans Members 1 and 2, $1.5 to 1.8 Ma) and East Africa (Olduvai East and Pening, $1.5 to 1.8 Ma). The d 13 C values of Paranthropus robustus, and Homo ergaster in South Africa show that a significant amount of food resources coming from C 4 environments (most likely savanna) were consumed by these three hominid species (data from Lee-Thorp et al., 2003). In contrast to Paranthropus robustus in South Africa, Paranthropus boisei from East Africa exhibits a diet almost completely composed of C 4 food resources, while Homo habilis had a diet with d 13 C values similar to Homo ergaster in South Africa.Figure 8 d 13 C and d 15 N values of short-faced bears (Arctodus simus) collagen from Alaska and Yukon, compared to those of coeval herbivorous and carnivorous species (data from Fox-Dobbs et al., 2008).These isotopic data of short-faced bears plot together with carnivorous species, such as lion, scimitar-toothed cat, and wolf, clearly indicating these that short-faced bears were carnivorous. ...
... Indeed, modern African apes are restricted to forested environments, and savanna environments require special skills in order to be exploited by primates, such as a bipedal gait and strong social bonds. The 13 C values of tooth enamel of fossil mammals, including hominids from South Africa, ranging in age from 3 to 1.7 million years old, indicate a significant C 4 component in the environment, as well as significant C 4 dietary inputs for hominids of the species Australopithecus africanus, A. robustus, and Homo ergaster ( Fig. 6; Lee- Thorp et al., 2003). This C 4 dietary input could be linked to the consumption of C 4 plant parts, but also to the consumption of animals feeding on C 4 plants, such as invertebrates, small vertebrates, or grazer meat. ...
... The 13 C values of browser and grazer enamel are similar to those of modern herbivores consuming C 3 plants (browsers) and C 4 plants (grazers), indicating preservation of the carbon isotopic signatures in the fossil material. The 13 C values of Australopithecus africanus, Australopithecus robustus, and Homo ergaster show that a significant amount of food resources coming from C 4 environments (most likely savanna) were consumed by these three hominid species during the Pliocene and Pleistocene in South Africa (Lee-Thorp et al. (2003)). ...
... Indeed, modern African apes are restricted to forested environments, and savanna environments require special skills for exploitation by primates, such as a bipedal gait and strong social bonds. The d 13 C values of tooth enamel of fossil mammals, including hominids, from South Africa, ranging in age from 1.8 to 1.5 million years old, indicate a significant C 4 component in the environment, as well as significant C 4 dietary inputs for hominids of the species Paranthropus robustus, and Homo ergaster (Figure 7; Lee- Thorp et al., 2000Thorp et al., , 2003Thorp et al., , 2010. This C 4 dietary input could be linked to the consumption of C 4 plant parts, but also to the consumption of animals feeding on C 4 plants, such as invertebrates, small vertebrates, or grazer meat. ...
... Reconstruction of the paleoenvironment and paleodiet of fossil hominids from South Africa (Swartkrans Members 1 and 2, $1.5 to 1.8 Ma) and East Africa (Olduvai East and Pening, $1.5 to 1.8 Ma). The d 13 C values of Paranthropus robustus, and Homo ergaster in South Africa show that a significant amount of food resources coming from C 4 environments (most likely savanna) were consumed by these three hominid species (data from Lee-Thorp et al., 2003). In contrast to Paranthropus robustus in South Africa, Paranthropus boisei from East Africa exhibits a diet almost completely composed of C 4 food resources, while Homo habilis had a diet with d 13 C values similar to Homo ergaster in South Africa.Figure 8 d 13 C and d 15 N values of short-faced bears (Arctodus simus) collagen from Alaska and Yukon, compared to those of coeval herbivorous and carnivorous species (data from Fox-Dobbs et al., 2008).These isotopic data of short-faced bears plot together with carnivorous species, such as lion, scimitar-toothed cat, and wolf, clearly indicating these that short-faced bears were carnivorous. ...
... Carbon isotopic tracking of palaeodiets has been successfully applied to decipher food preferences of extinct African hominids (e.g. Lee-Thorp et al., 2003;Cerling et al., 2011Cerling et al., , 2013Sponheimer et al., 2013). This approach has, in several cases, yielded unexpected results compared to the conclusions of ecomorphological or tooth microwear analyses. ...
Article
Full-text available
Determining the diet of fossil apes is essential to understand primate evolution. The giant form from Southeast Asia, Gigantopithecus blacki, may have been up to 270 kg and survived until about 100,000 years ago. It is known only from isolated teeth and a few lower jaws with reduced front teeth and enlarged molars and premolars. A large spectrum of diets has been suggested for Gigantopithecus, ranging from carnivorous or grass-feeding in open savannah to a vegetarian diet dominated by fruits or bamboo. To determine its habitat and to understand why it became extinct, we tried to evaluate its dietary niche. The carbon stable isotopic composition of tooth enamel of this taxon compared to coeval and extant mammals from Southeastern Asia show that Gigantopithecus was a forest-dweller with a generalist vegetarian diet and was not specialized on bamboos. In southern China, Gigantopithecus lived in a forested environment, as did the coeval fauna, while in Thailand, it occupied only the forested part of a mosaic landscape including significant parts of open savannah. The carbon isotopic compositions of Gigantopithecus were different from those of omnivorous and carnivorous taxa, but very similar to those of orang-utans and unlike those of the bamboo-specialist giant panda. Therefore, even when open savannah environments were present in the landscape, Gigantopithecus foraging was limited to forested habitats. The very large size of Gigantopithecus, combined with a relatively restricted dietary niche, may explain its demise during the drastic forest reduction that characterized the glacial periods in South East Asia.
... However, when separated into taxonomic groups and temporal intervals, there are statistically significant differences among hominin d 18 O EC mean values and variances. Although Lee-Thorp et al. (2003) Cerling et al. (2011aCerling et al. ( , 2013b and associated hominin identity (taxon, tooth type and number, body size), drinking and dietary (d 13 C EC value, Turkana coeval and modern mammalian d 18 O EC values), and contextual (time, depositional environment) information of each specimen and fossil collecting area in order to detect various potential influences. ...
... Considering the available data on the Miocene hominoid (including hominids) locomotor behaviours, it is obvious that these hominoids were adapted to more or less wooded environments, an aspect which is confirmed by the data from palaeontology and geochemistry ( Pickford et al. 1987;Wang & Cerling, 1994;Cerling et al. 1997Cerling et al. , 2011Lee-Thorp et al. 2003;Nakaya & Tsujikawa, 2006;Uno et al. 2011;Roche, 2012;Domingo et al. 2013;Roche et al. 2013). We do not know all the locomotor repertoires for the numerous Miocene hominoid species, but the more complete skeletons indicate clear arboreal adaptations such as arboreal quadrupedalism, climbing and orthograde postures. ...
Article
Linking the environment to functional anatomy is not an easy exercise, especially when dealing with fossils, which are often fragmentary and represent animals that are extinct. A holistic approach permits us to fill the gaps in reconstructing the evolutionary patterns in fossil groups. Identifying the environment where animals lived can help to interpret some anatomical structures and, vice versa, the functional morphological pattern can help to refine some fossil environments. Two examples focusing on locomotor behaviours in fossil mammals are considered in this paper: the hominoids and the origins of hominid bipedalism and the springing adaptations in fossil rodents (Pedetidae) in connection with different habitats. In the first case, the limits of the chimp-based models and the necessity to take into account detailed environmental reconstructions will be addressed. The famous ‘savannah hypothesis’ is no longer tenable because the palaeontological data support a more vegetated environment for the origins of bipedal hominids. Data from the environment will be considered. The earliest putative hominid fossils which preserve skeletal remains of the locomotor apparatus show mixed adaptations to terrestrial bipedalism and arboreal activities. The second example focuses on the variation in springing adaptations in Pedetidae in the Lower Miocene of East Africa and Southern Africa. In the East, the sites where Pedetidae were preserved were mainly forested, whereas in the South the region was more open and drier, with extensive grassy patches. In the first case, pedetids were robust and heavy jumpers, whereas in the South they were smaller, their skeleton more gracile and their springing was lighter. During the desertification of the southern part of Africa, the large pedetid species became extinct, but a smaller species developed. In the case of primates, as in the case of rodents, the skeletal morphology was adapted to its environment.
... As extant primates occupy a broad spectrum of dietary niches, ranging from the committed faunivory of Tarsius to near total graminivory in Theropithecus, documenting diet is a critical component of discovering the ecological roles that primates play in their environments. Analysis of tooth morphology is useful for determining the potential diets and fallback capabilities of primates, but direct evidence of diet detected through elemental signatures imparted on hard tissue (i.e., isotope studies) (Sponheimer et al., 1999;Lee-Thorp et al., 2003) or wear caused on enamel by food particles (i.e., microwear studies) (Teaford and Walker, 1984;Ungar et al., 2003) offers an advantage as this evidence reflects actual interactions between animal and environment; it tells us something about what animals actually ate rather than what they were capable of eating or adapted to eat. Analysis of dental microwear is particularly useful in this regard, as it provides direct evidence of the interaction between food components (such as phytoliths and plant silicates) and the enamel surfaces of a tooth, allowing documentation of the types of food that were consumed in an animal's last few weeks of life (Grine, 1986). ...
... Such activities are unlikely to be preserved in the archaeological record (but see d'Errico, 2001, 2008). Similarly, no distinctive isotope signature for insectivory has been identified in hominin bones or teeth (Lee-Thorp et al., 2003;Peters and Vogel, 2005;Sponheimer et al., 2005Sponheimer et al., , 2006 nor has a distinctive insectivorous pattern been identified in hominin dental microwear (Teaford, 2007; but see Strait, 2014). While new lines of evidence are being identified and developed (see McGrew, 2001McGrew, , 2014, studying the behavior of living apes remains a viable approach to understanding the possible contribution of insects to the diets of early human ancestors. ...
... This ratio can be used in dietary reconstruction to detect seasonality, identify individuals who may be 'non-local' and as a paleoclimatic proxy. [35][36][37][38] Here, the δ 13 C and δ 18 O values of bone apatite with and without lipid removal were examined to assess potential isotopic shifts. ...
Article
Full-text available
Rationale: Bone lipid compound-specific isotope analysis (CSIA) and bone collagen and apatite stable isotope ratio analysis are important sources of ecological and paleodietary information. Pressurized liquid extraction (PLE) is quicker and utilizes less solvent than traditional methods of lipid extraction such as soxhlet and ultrasonication. This study facilitates dietary analysis by optimizing and testing a standardized methodology for PLE of bone cholesterol. Methods: Modern and archaeological bone were extracted by PLE using varied temperatures, solvent solutions, and sample weights. The efficiency of PLE was assessed via quantification of cholesterol yields. Stable isotopic ratio integrity was evaluated by comparing isotopic signatures (δ(13) C and δ(18) O values) of cholesterol derived from whole bone, bone collagen and bone apatite. Gas chromatography/mass spectrometry (GC/MS) and gas chromatography isotope ratio mass spectrometry (GC/IRMS) were conducted on purified collagen and lipid extracts to assess isotopic responses to PLE. Results: Lipid yield was optimized at two PLE extraction cycles of 75 00B0C using dichloromethane/methanol (2:1 v/v) as a solvent with 0.25-0.75 g bone sample. Following lipid extraction, saponification combined with the derivatization of the neutral fraction using trimethylsilylation yielded nearly twice the cholesterol of non-saponified or non-derivatized samples. It was also found that lipids extracted from purified bone collagen and apatite could be used for cholesterol CSIA. There was no difference in the bulk δ(13) C values of collagen extracted from bone with or without lipid. However, there was a significant depletion in (18) O of bone apatite due to lipid presence or processing. Conclusions: These results should assist sample selection and provide an effective, alternative extraction method for bone cholesterol that may be used for isotopic and paleodietary analysis.
... Based on faunal, flora and isotope studies a mozaic environment has been reconstructed, which in the early-mid-Pleistocene, was more forested than today, with gallery forests along watercourses and nearby patchy open grasslands or woodland habitats in which Australopiths enjoyed a mixed C3-C4 diet on dolomite or mixed dolomite-shale-granite substrate (e.g. Vrba, 1982;Bamford, 1999;Lee-Thorp et al., 2003;Sponheimer and Lee-Thorp, 2003;Sponheimer et al., 2005Sponheimer et al., , 2006Reynolds, 2007;Bamford et al., 2010;Copeland et al., 2011). Au. sediba lived in the center of this broadly C4 environment, and enjoyed a dedicated C3 diet (Henry et al., 2012), indicating strong variability in hominin behavior. ...
Article
Full-text available
This paper provides constraints on the evolution of the landscape in the Cradle of Humankind (CoH), UNESCO World Heritage Site, South Africa, since the Pliocene. The aim is to better understand the distribution of hominin fossils in the CoH, and determine links between tectonic processes controlling the landscape and the evolution and distribution of hominins occupying that landscape. The paper is focused on a detailed reconstruction of the landscape through time in the Grootvleispruit catchment, which contains the highly significant fossil site of Malapa and the remains of the hominin species Australopithicus sediba.
... The amount of data concerning the origins of hominids is important, and two main schools of thought emerge depending on the timing of the emergence of hominids. But, even recent studies have considered only early Homo and/or australopithecines (Australopithecus + Paranthropus) in their hypothesis regarding the environment in which hominids evolved: they consider a savannah environment, more or less dry and more or less humid (Cerling et al. 1997(Cerling et al. , 2011Lee-Thorp et al. 2003;Roche et al. 2013;Ségalen et al. 2007). Bonnefille (2010) suggested the presence of Miombo woodland in some Mio-Pliocene sites in Ethiopia and this suggest a wider distribution of this vegetation ( Figure 6). ...
Article
It has long been accepted that hominids emerged during the Pliocene in a savannah environment in which a terrestrial quadruped gradually developed bipedal adaptations. However, data from the Late Miocene (i.e. 7–7.5 Ma), including detailed palaeontological and biogeochemical studies, suggest that our earliest Upper Miocene ancestors inhabited well-wooded to forested environments where they could have spent a certain amount of time in the trees. A plausible type of ecosystem in which upright posture and bipedal locomotion could have emerged is represented by Miombo Woodland, in which vertical arboreal supports predominate and trees are separated from each other by gaps. Subsequently hominids dispersed into the Savannah as accomplished bipeds, but retained the ability to climb trees. This scenario is compatible with the postcranial anatomy of Australopithecus, including its femoral elongation, body proportions, manual precision grip (also present in 6-million-year-old Orrorin) and a non-prehensile hallux.
... Controlled feeding experiments provided vital perspectives on the systematics, caveats and capabilities of isotopic approaches (e.g. DeNiro & Epstein 1978a;Tieszen et al. 1983;Ambrose & Norr 1993;Ambrose 2000;Howland et al. 2003;Sponheimer et al. 2003). Of equal importance were studies of the ways isotope ratios can be altered after burial (e.g. ...
Article
Full-text available
Given their ubiquity in dietary reconstruction, it is fitting that the story of isotopes began with a conversation over dinner. Although coined in scientific literature by Frederick Soddy (1913), the word ‘isotope’ was first conceived by Margaret Todd, a medical doctor (also known as the novelist ‘Graham Travers’, and an all-round gender-stereotype-smasher of their age). In 1912, Soddy and Todd were attending a supper in Glasgow. When talk turned to work, Soddy described the then nameless concept of elements of different masses that occupy the same place in the periodic table. Todd suggested the term ‘isotope’, from the Greek isos (‘same’) + topos (‘place’), and the name stuck (Nicol 1957; Nagel 1982).
... Subsequent analyses that incorporate red-tailed monkey food source distribution and diversity should reveal whether dietary composition, in addition to home range sizes, also differs between forest and savana mosaic populations. Moreover, dental microwear and isotopic comparison of the available plants in these forests should provide extant analogues for comparisons of especially contemporaneous fossil hominins (sensu Lee-Thorp, Sponheimer, & van der Merwe, 2003 ...
Article
Objectives: Primates that live in predominantly forested habitats and open, savanna mosaics should exhibit behavioral responses to differing food distributions and weather. We compared ecological constraints on red-tailed monkey ranging behavior in forest and savanna mosaic environments. Intraspecific variation in adaptations to these conditions may reflect similar pressures faced by hominins during the Plio-Pleistocene. Methods: We followed six groups in moist evergreen forest at Ngogo (Uganda) and one group in a savanna-woodland mosaic at the Issa Valley (Tanzania). We used spatial analyses to compare home range sizes and daily travel distances (DTD) between sites. We used measures of vegetation density and phenology to interpolate spatially explicit indices of food (fruit, flower, and leaves) abundance. We modeled DTD and range use against food abundance. We modeled DTD and at Issa hourly travel distances (HTD), against temperature and rainfall. Results: Compared to Issa, monkeys at Ngogo exhibited significantly smaller home ranges and less variation in DTD. DTD related negatively to fruit abundance, which had a stronger effect at Issa. DTD and HTD related negatively to temperature but not rainfall. This effect did not differ significantly between sites. Home range use did not relate to food abundance at either site. Conclusions: Our results indicate food availability and thermoregulatory constraints influence red-tailed monkey ranging patterns. Intraspecific variation in home range sizes and DTD likely reflects different food distributions in closed and open habitats. We compare our results with hypotheses of evolved hominin behavior associated with the Plio-Pleistocene shift from similar closed to open environments.
... 13 C values represent the relative depletion of a body tissue in 13 C to the standard PDB (Pee Dee Belemnite), which contains more 13 C than nearly all dietary resources and most human tissues (Chisholm, 1989;Katzenberg, 1992;Ambrose, 1993). Plant and animal values are thus displayed in negative figures, with C 3 plant eating herbivores and their consumers averaging in around À12& and lower and C 4 plant eating herbi- vores and their consumers averaging values nearer to 0& for apatite ( Lee-Thorp et al., 2003). ...
... Stable isotopes of carbon (δ 13 C), from bulk collagen, are commonly used in palaeodietary reconstruction studies and are most effective at establishing the source of plant protein in the diet (Pollard et al., 2007;Schwarcz and Schoeninger, 2011;Walker and DeNiro, 1986). The δ 13 C values in bone collagen originate from plants, as the base of all terrestrial food webs, and this can be either as a result of direct consumption or via a vector, such as an animal; herbivores incorporate consumed plant carbon into their tissues, which then reflects the proportion of C 3 and C 4 plants eaten (Lee-Thorp et al., 2003). Furthermore, the analysis of δ 13 C values (in conjunction with δ 15 N) can be used to identify the input of marine resources in the diet (see Andrade et al., 2015;Bocherens et al., 2016;Ingvarsson-Sundström et al., 2009;Walker and DeNiro, 1986 among others). ...
Article
C and N isotopes (collagen), trace elements (apatite), and WARN modeling conducted on sub-adults from prehistoric İkiztepe. •The weaning age is suggested enabling greater understanding of the weaning process and population dynamics. •WARN has emphasised the lag effect in living bone as something to be considered when examining the weaning process. •Reconsideration of the utility of trace element analyses, and the importance of utilising a holistic approach.
... Middle Pliocene hominin δ 13 C EC values grouped by identified species and/or separated into temporal bins (e.g., Patterson et al., 2019) show a directional shift toward consumption of C 4 foods, which may have included C 4 sedges and grass seeds, underground storage organs, insects (e.g., termites) and other arthropods, bird's eggs, as well as C 3 -C 4 -mixed-and C 4 -feeding vertebrates (Peters and Vogel, 2005;Sponheimer and Lee-Thorp, 2003;Yaekel et al., 2007). There is also an increase in δ 13 C EC variance, which has been interpreted to indicate dietary niche expansion relative to the earliest hominins (i.e., Ardipithecus and A. anamensis) and extant chimpanzees (Antón et al., 2014;Levin et al., 2015;Lee-Thorp et al., 2003, 2010Sponheimer et al., 2013;. The earliest mixed C 3 -C 4 feeding hominins with measured δ 13 C EC values and identified to species are A. bahrelghazali at 3.6 Ma (Lee- , A. afarensis at 3.4 Ma , and in the OTD, K. platyops at 3.4 Ma (Cerling et al., 2013b) (Fig. 3). ...
... Multiple studies confirm that teeth, in particular their enamel, are a relatively durable part of the skeleton and they undergo ionic exchanges to a lesser extent that bones, both ante mortem and post mortem (Zazzo, 2014;Zazzo et al., 2004b). Because of the low organic substance content and the large phosphate crystallites, the diagenetic processes in enamel are considered to progress much more slowly than in other tissues (Lee-Thorp et al., 2003;Sponheimer and Lee-Thorp, 2001). However, even enamel may degrade in unfavourable conditions in the grave and it is therefore necessary to analyse enamel samples for diagenesis (Roche et al., 2010). ...
Article
Diagenetic alterations may limit the potential use of archaeological bones and teeth as a reliable source of information about the origin and movement of people and animals, their diet and the environment in which they lived. Fourier transform infrared spectroscopy (FTIR) has been widely applied to determine the overall state of preservation of ancient bones. Spectral data are commonly used to quantify two diagenetic indicators related to sample crystallinity: the splitting factor (SF), the hydrogen phosphate ion index (HPO4/PO4) and the width at 85% of the height of the 604 cm⁻¹ peak (FW85%). The aim of the present work is to determine the presence of any difference in the value of SF, HPO4/PO4 and FW85% of the 604 cm⁻¹ peak between tissues such as enamel, dentine and bone. This method has been applied to two different modern animals: sheep and pigs. The results obtained in this study demonstrate that enamel has significantly higher values of the SF and significantly lower values of HPO4/PO4 and FW85% in comparison to bone and dentine in both animal species. Moreover, enamel has been reported to show diversification of SF index across the investigated species, which is presumably related to different tooth development and mineralisation patterns in animals with different diets (i.e. herbivorous versus omnivorous). The present study demonstrates that due to the different biogenic chemical structure of bones and teeth, the SF and HPO4/PO4 reference ranges should be determined separately for each of the three tissues, and in the case of enamel also allowing for the analysed species.
Article
Diet has had a deep and wide-ranging impact on human evolution. Contemporary genome was originally selected for the lifestyle of ancestral humans. Since human genome has little changed since the emergence of behaviourally modern humans, the study of prehistoric hunter–gatherer diet could be regarded as a paradigm for modern humans. The discordance between our ancestral, genetically determined biology and the nutritional and activity patterns of contemporary western populations could be the common soil for the emergence and wide spreading of metabolic disease, such as obesity and T2 diabetes.
Article
The analytical framework of human population genetics has completed a cycle: the lineagebased description of mitochondrial DNA and Y chromosome diversity, where often populations vanished, to be replaced by marauding hordes of disembodied haplogroups, is giving way to the multivariant analysis of SNP allele frequencies, rehashing the toolkit pioneered by Cavalli-Sforza in the late 1980s. Now, however, population definition is left to Bayesian algorithms, creating a tension between the individual, the population as socially defined, and reified Bayesian population constructs. This chapter reviews recent literature on African population genetics. East Africa can be imagined as a source or sink of population movements. Some argue that Southern Africa is a serious candidate to be humankind's cradle, though contrary evidence suggests that the Bantu expansion homogenized a vast swathe of Africa. The multifaceted nature of Pygmy populations is explored in relation to this, and the place of populations north of the Sahara.
Article
Cercopithecines are common in hominid producing deposits and are a useful proxy for determining the ecological context of the early hominids. For this study, dental microwear is examined through low-magnification stereomicroscopy and used to reconstruct the diets of sampled primates. Those from the earliest sites, predominantly Parapapio, are primarily frugivorous while the incidence of gramnivory increases in the later Dinopithecus, Gorgopithecus, and Papio individuals denoting a general cooling and drying trend over the South African Plio-Pleistocene with a distinct pulse between 1.9-1.8 million years ago (mya). Australopithecus is reconstructed as a primary gramnivore which indicates that hominids adapted early in their evolution to expanding grasslands. INDEX WORDS: Paleoecology, dental microwear, Australopithecus, Parapapio, Dinopithecus, Papio, Gorgopithecus.
Article
Full-text available
In the present study the cranial morphology of five prehistoric human skulls from Serra da Capivara, Piauí, Brazil was assessed under a comparative perspective. The specimens are dated to either the Early or the Late Holocene. The multivariate analyses conducted (Principal Components and Discriminant Functions) showed that the specimens from this region of Brazilian Northeast resolve in two very distinct and distant groups in the morphspace. When their morphologies were compared to the world cranial variation, the group formed by Coqueiros and Paraguaio 1 exhibit s a clear association with Australo-Melanesians and Africans, while the group formed by Caboclos, Gongo and Paraguaio 2 exhibits a clear association with nowadays Asians and Native Americans. These result s are congruent with the idea that the Americas were successively settled by two dif ferent Asian populations. Neste trabalho a morfologia de cinco crânios humanos oriundos da Serra da Capivara, Piauí, Brasil, dat ados do Holoceno Antigo e Tardio é estudada sob uma perspectiva comparativa. Os resultados mostram que esses espécimes se resolvem em dois grupos coesos e distantes entre si no morfo-espaço. Quando a morfologia dos espécimes do nordeste brasileiro é comparada com a variabilidade craniana mundial, o grupo formado por Coqueiros e Paraguaio 1 mostra clara afinidade com australo-melanésios e africanos atuais; já o grupo formado por Caboclos, Gongo e Paraguaio 2 mostra grande afinidade morfológica com os asiáticos e índios americanos atuais. Esses resultados apóiam a idéia de que a América foi povoada sucessivamente por duas populações asiáticas distintas. Primeiros americanos Análise multivariada Piauí
Article
Full-text available
Theropithecus was a common large-bodied primate that co-occurred with hominins in many Plio-Pleistocene deposits in East and South Africa. Stable isotope analyses of tooth enamel from T. brumpti (4.0-2.5 Ma) and T. oswaldi (2.0-1.0 Ma) in Kenya show that the earliest Theropithecus at 4 Ma had a diet dominated by C4 resources. Progressively, this genus increased the proportion of C4-derived resources in its diet and by 1.0 Ma, had a diet that was nearly 100% C4-derived. It is likely that this diet was comprised of grasses or sedges; stable isotopes cannot, by themselves, give an indication of the relative importance of leaves, seeds, or underground storage organs to the diet of this primate. Theropithecus throughout the 4- to 1-Ma time range has a diet that is more C4-based than contemporaneous hominins of the genera Australopithecus, Kenyanthropus, and Homo; however, Theropithecus and Paranthropus have similar proportions of C4-based resources in their respective diets.
Article
Full-text available
Light stable isotope ratios (δ13C and δ18O) of tooth enamel have been widely used to determine the diets and water sources of fossil fauna. The carbon isotope ratios indicate whether the plants at the base of the food web used C3 or C4 photosynthetic pathways, while the oxygen isotope ratios indicate the composition of the local rainfall and whether the animals drank water or obtained it from plants. The contrasting diets of two early hominin species - Homo habilis and Paranthropus boisei - of ca 1.8 Ma (million years ago) in Tanzania were determined by means of stable carbon isotope analysis of their tooth enamel in a previous study. The diets of two specimens of P boisei, from Olduvai and Peninj, proved to be particularly unusual, because 80% of their carbon was derived from C4 plants. It was suggested that their diet consisted primarily of plants, with particular emphasis on papyrus, a C4 sedge. The dominance of C4 plants in the diet of P boisei is a finding supported in another study of 22 specimens from Kenya. The isotopic ecology and diets of fossil fauna that were present at the same time as the two fossil hominin species are described here, in order to provide a fuller understanding of their contrasting diets and of the moisture sources of their water intake. This information was then compared with the isotopic composition of modern fauna from the same region of Tanzania. The carbon isotope ratios for both fossil and modern specimens show that the habitats in which these faunal populations lived were quite similar - grassland or wooded grassland. They had enough bushes and trees to support a few species of browsers, but most of the animals were grazers or mixed feeders. The oxygen isotope ratios of the fossil and modern fauna were, however, very different, suggesting strongly that the source of moisture for the rain in the Olduvai region has changed during the past 1.8 million years.
Book
Isotopes are forms of an element that differ in the number of neutrons. Isotopes function as natural dyes or colors, generally tracking the circulation of elements. Isotopes trace ecological connections at many levels, from individual microbes to whole landscapes. Isotope colors mix when source materials combine, and in a cyclic process that ecologists can appreciate, the process of isotope fractionation takes the mixed material and regenerates the sources by splitting or fractionating the mixtures. Elements and their isotopes circulate in the biosphere at large, but also in all smaller ecological plant, animal, or soil systems. Chapter 3 reviews this circulation for each of the HCNOS elements, then gives four short reviews that may stimulate you to think about how you could use isotopes in your own ecological research.
Article
Hominin-cercopithecid comparisons have been used in palaeoanthropology for over forty years. Fossil cercopithecids can be used as a ‘control group’ to contextualize the adaptations and evolutionary trends of hominins. Observations made on modern cercopithecids can also be applied to questions about human evolution. This article reviews the history of hominin-cercopithecid comparisons, assesses the strengths and weaknesses of cercopithecids as comparators in studies of human evolution, and uses cercopithecid models to explore hominin inter-specific dynamics. Cercopithecids appear to be excellent ecological referents, but may be less good when considering the cognitive abilities and cultural adaptations of hominins. Comparison of cercopithecid and hominin adaptations at Koobi Fora in East Africa indicates that, whereas the cercopithecids were largely grass- or leaf-eating, the hominins occupied a generalist niche, apparently excluding other primate generalist-frugivores. If any of the hominin species at Koobi Fora were sympatric, analogies with modern cercopithecids suggest that inter-specific contact cannot be discounted and may even have been beneficial.
Book
This is the first book to provide a systematic overview of social zooarchaeology, which takes a holistic view of human–animal relations in the past. Until recently, archaeological analysis of faunal evidence has primarily focused on the role of animals in the human diet and subsistence economy. This book, however, argues that animals have always played many more roles in human societies: as wealth, companions, spirit helpers, sacrificial victims, totems, centerpieces of feasts, objects of taboos, and more. These social factors are as significant as taphonomic processes in shaping animal bone assemblages. Nerissa Russell uses evidence derived from not only zooarchaeology, but also ethnography, history, and classical studies to suggest the range of human–animal relationships and to examine their importance in human society. Through exploring the significance of animals to ancient humans, this book provides a richer picture of past societies.
Chapter
Humans evolved in the dynamic landscapes of Africa under conditions of pronounced climatic, geological and environmental change during the past 7 million years. This book brings together detailed records of the paleontological and archaeological sites in Africa that provide the basic evidence for understanding the environments in which we evolved. Chapters cover specific sites, with comprehensive accounts of their geology, paleontology, paleobotany, and their ecological significance for our evolution. Other chapters provide important regional syntheses of past ecological conditions. This book is unique in merging a broad geographic scope (all of Africa) and deep time framework (the past 7 million years) in discussing the geological context and paleontological records of our evolution and that of organisms that evolved alongside our ancestors. It will offer important insights to anyone interested in human evolution, including researchers and graduate students in paleontology, archaeology, anthropology and geology.
Article
While many models have been developed to depict the behavior and ecology of our earliest relatives, the Man the Hunter model has been the most widely accepted view of human evolution. Many human traits (e.g., bipedalism, tools, and fire) are often linked to this perspective. Theories of human aggressive hunters abound but are rarely based on evidentiary approaches. Here is outlined a methodology using the fossil record and extant primate ecology and behavior. Data on fossil humans, modern primates, and rates of predation indicate that Man the Hunted may be the most accurate descriptor of our earliest relatives.
Data
Full-text available
Using 13C-, 15N- and 18O stable isotope analysis of human bone tissue to identify transhumance, high altitude habitation and reconstruct palaeodiet for the early medieval Alpine population at Volders, Austria. (PDF)
Article
Full-text available
The paper describes the current situation in Russian regional archaeology in connection with the promotion of interdisciplinary research in the ecological paradigm, approaches and methods for reconstructing the life-support systems and paleodiet of the ancient population. Two main approaches to paleodiet reconstruction are examined. The first one involves direct empirical calculations on ecofacts that reflect the various components of the paleodiet. It is suitable for limited types of deposits with good preservation, mainly shell mounds. It is stated that there are contradictions in modern implementations of empirical calculations for the reconstruction of life-support systems and paleodiet models when the carbohydrate component “escapes” from the attention of researchers. One of the proposed productive technics for overcoming the contradiction is a research method of ancient starch on tools and ceramics. This method has informative capabilities and prospects for its application. The second approach is based on methods for studying chemical markers of using certain food sources. These markers can be found in bones, teeth, other body tissues and ceramics. The authors analyze in detail the conditions, information capabilities and limitations of the use of each of the methods and their combination for the most complete reconstruction of the life-support system and the paleodiet. A critical review of the results from various approaches and methods of the paleodiet analysis in regional archeology is also carried out. The integrated approaches and methods for a more complete reconstruction of the life-support systems and paleodiet are proposed. Keywords: human behavioral ecology, archeology, paleodiet reconstruction methods, research method of ancient starch, isotope analysis.
Article
The mandibular third premolar (P3) exhibits substantial differences in size and shape among hominoid taxa, and displays a number of discrete traits that have proven to be useful in studies of hominin taxonomy and phylogeny. Discrete traits at the enamel-dentine junction (EDJ) can be accurately assessed on moderately worn specimens, and often appear sharper than at the outer-enamel surface (OES). Here we use microtomography to image the P3 EDJ of a broad sample of extant apes, extinct hominins and modern humans (n = 100). We present typologies for three important premolar discrete traits at the EDJ (transverse crest, marginal ridge and buccal grooves), and score trait frequencies within our sample. We find that the transverse crest is variable in extant apes, while the majority of hominins display a transverse crest which runs directly between the two major premolar cusps. Some Neanderthals display a unique form in which the transverse crest fails to reach the protoconid. We find that mesial marginal ridge discontinuity is common in Australopithecus anamensis and Australopithecus afarensis while continuous marginal ridges largely characterize Australopithecus africanus and Paranthropus. Interrupted mesial and distal marginal ridges are again seen in Homo sapiens and Neanderthals. Premolar buccal grooves, previously identified at the OES as important for hominin systematics, are again found to show a number of taxon-specific patterns at the EDJ, including a clear difference between Australopithecus and Paranthropus specimens. However, their appearance may be dependent on the morphology of other parts of the crown such as the protoconid crest, and the presence of accessory dentine horns. Finally, we discuss rare variations in the form of dentine horns that underlie premolar cusps, and their potential homology to similar morphologies in other tooth positions.
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
The importance of diet in primate ecology has motivated the use of a variety of methods to reconstruct dietary habits of extinct hominin taxa. Dental microwear is one such approach that preserves evidence from consumed food items. This study is based on 44 specimens of Australopithecus africanus from Makapansgat and Sterkfontein, and 66 specimens of Paranthropus robustus from Swartkrans, Kromdraai and Drimolen. These samples enable examination of potential differences between the two assemblages of A. africanus, and among the various assemblages of P. robustus in relation to the paleoenvironmental reconstructions that have been proffered for each fossil site. Sixteen microwear texture variables were recorded for each specimen from digital elevation models generated using a white-light confocal profiler. Only two of these differ significantly between the Makapansgat and Sterkfontein samples of A. africanus. None of the microwear texture variables differs significantly among the samples of P. robustus. On the other hand, P. robustus has significantly higher values than A. africanus for 11 variables related to feature complexity, size, and depth; P. robustus exhibits rougher surfaces that comprise larger, deeper features. In contrast, A. africanus has smoother, simpler wear surfaces with smaller, shallower and more anisotropic features. As for possible habitat differences among the various sites, only a relatively small number of subtle differences are evident between the specimens of A. africanus from Makapansgat and Sterkfontein, and there are none among the specimens of P. robustus from various deposits. As such, it is reasonable to conclude that, while subtle differences in microwear textures may reflect differences in background habitats, the wear fabric differences between P. robustus and A. africanus are most reasonably interpreted as having been driven by dietary differences.
Article
Dietary proxies for inferring diet composition of African hominin species have been widely used. However, results derived from buccal microwear patters, occlusal textural data and carbon stable isotope are not always concordant. We have analyzed the correlations between the different variables measured with each methodological approach at two distinct levels. We first, computed paired correlation among fossil specimens for whom dietary data was available and then analyzed the trends in dietary proxies variables among the fossil hominin species considered. The results show some significant correlations between variables. However, some inconsistencies among the different methodologies are evident, especially between buccal and occlusal microwear proxies and between the microwear patterns and δ¹³C signals. Differences in age ranges and life span for applying the different techniques might explain the inconsistencies observed. Further data on dental microwear patterns are required for further a more informative investigation on the associations between the dietary proxies.
Article
Many models have been developed to depict the behavior and ecology of our earliest relatives. However, the Man the Hunter model has been the most widely accepted way of viewing human evolution. This theory gained ground in the mid-twentieth century and has been recycled ever since under various guises in the scientific and popular literature. Many human traits, such as bipedalism, monogamy, territoriality, tool use, technological invention, male aggression, group living, and sociality, are often linked to this perspective. Although theories and associations of human aggressive hunters abound, they are rarely based on the two evidentiary approaches that shed light on early hominin ecology and behavior-living primate models and the fossil record. Here, an outline is given on a methodology of reconstructing early human behavior by using both the fossil record and extant primate ecology and behavior. Data on early human fossils, on modern primates living in similar habitats to our earliest ancestors, and on rates of predation both today and in the distant past indicate that Man the Hunted may be a more accurate descriptor of our earliest relatives. Here evidence for the Man the Hunted theory, some of the behavioral patterns that were needed to protect our earliest ancestors from predation, and how this may lead to a new perspective on certain aspects of human nature are described.
Article
Tarihî ve arkeolojik topluluklarda beslenme geleneksel olarak etnografik, yazılı kayıtlar, arkeozoolojik ve arkeobotanik kalıntılar ve benzeri kaynaklar kullanılarak yeniden oluşturulmakla birlikte, bu veri kaynakları bize yalnızca hangi kaynakların mevcut olduğunu söyleyebilir. Bununla birlikte, sabit izotop analizleri, tüketilen gıdaların geniş kategorilerinin doğrudan bir ölçümünü sağlar. İnsan ve hayvan kemiğinden özütlenen kolajenin sabit karbon ve azot izotop bileşimi, geçmiş insan topluluklarının beslenme alışkanlıklarını, geçim stratejilerindeki değişimi, göçü, ürün yetiştirme ve hayvancılık uygulamalarındaki değişiklikleri, topluluk içinde zamana, yaşa, cinsiyete veya gömü geleneğine göre beslenme varyasyonunu gözlemlemek ve sütten kesme süreci belirleyebilmek için kullanılır. Türkiye’de sabit izotopların arkeolojik ve tarihi materyallere uygulanması nispeten geç başlamış ve ilk çalışma 2003 yılında yapılmıştır. Gelecekte, farklı bölgelerden ve zaman periyodlarından daha fazla sayıda ve daha büyük örnek setlerini analiz ederek bilgimizi ve anlayışımızı geliştirebilir ve ilerletebilir, böylelikle de meta veri analizi için daha büyük bir izotop veri seti oluşturulabilir ve bireyler, yerleşimler, dönemler ve bölgeler arasında karşılaştırmalı çalışmalar yapabiliriz. Diet in historic and archaeological populations has traditionally been reconstructed using ethnographic, textual records, archaeozoological and archaeobotanical remains etc., but these data sources can tell us only what resources were available. However, stable isotope analyses provide a direct measure of the broad categories of foods that were actually exploited and consumed. Thus, stable carbon and nitrogen isotopes composition of collagen extracted from human and animal bone can be used in dietary studies of past human populations to observe changes in subsistence strategies, migration, crop and animal managements, intra-population variation in diet over time or by age, sex, burial type, and weaning process. The application of stable isotopes to archaeological and historic materials was a relatively late bloomer in Turkey, with the first study not conducted until 2003. For future perspectives, by analysing a greater number, and larger sample sets from different regions and time periods we can improve and advance our knowledge and understanding, creating a larger dataset of isotopic values for metadata analysis and cross comparisons between individuals, sites, time periods, and across regions.
Chapter
Stable isotopes have become an important tool to study diets and behavior of fossil mammals, but the path to acceptance has been long and arduous. Phosphate studies apply only to oxygen isotopes and dietary information is lacking; likewise, collagen is rarely preserved in fossils older than some thousands of years. This chapter discusses isotope ratios that are preserved in the carbonate component of tooth enamel. It first reviews isotopic analysis of the diets of extant mammals from Africa and looks at the dietary history of different mammalian lineages. It then examines the correspondence between the isotopic evidence for the transition from a C3 to a C4 world and the paleontological evidence for faunal change at the end of the Miocene and beginning of the Pliocene as shown by the faunal assemblages from Lothagam, northern Kenya. This faunal turnover is one of the most marked in the Cenozoic. Lastly, the chapter discusses future directions of stable isotope paleoecology.
Article
This review charts the developments and progress made in the application of stable light isotope tools to palaeodietary adaptations from the 1970s onwards. It begins with an outline of the main principles governing the distribution of stable light isotopes in foodwebs and the quality control issues specific to the calcified tissues used in these analyses, and then proceeds to describe the historical landmark studies that have marked major progress, either in their archaeological applications or in enhancing our understanding of the tools. They include the adoption of maize agriculture, marine-focused diets amongst coastal hunter–gatherers, trophic level amongst Glacial-period modern humans and Neanderthals, and the use of savannah resources by early hominins in Africa. Particular attention is given to the progress made in addressing the challenges that have arisen out of these studies, including issues related to the routing of dietary nutrients. I conclude with some firm, and some more speculative, pointers about where the field may be heading in the next decade or so.
Article
Full-text available
The interpretation of the baboon protogelada evolutionary transition as a response to the exploitation of new food resources, the availability of grasses and their seeds in open savanna country, is reasonable on dental and ecological evidence. But the extension of this model by Jolly (1970) to explain hominid origins is not justified, as detailed functional comparison of the known hominid dentitions indicates. It appears that the morphotype of the Plio Pleistocene hominid dentitions evolved in response to strong positive selection for increased incisivation and increased molar ability to withstand compressive forces. It is argued that these features, given the phylogenetic heritage of the first hominids from their pongid ancestry, are particularly appropriate to meat tearing and bone crushing, and that the protohominid dentition became adapted to a dietary regime consisting primarily, but not exclusively, of scavenging.
Article
Full-text available
Stable carbon isotope analysis is now an established tool for investigating the diets of fossil taxa, but carbon isotopes provide us with limited information about an animal's ecology. Recent research suggests that mammalian oxygen isotope compositions might also prove profitable sources of ecological information. If we are to exploit this resource, however, we must improve our nascent understanding of oxygen isotope compositions within modern foodwebs. To this end, we have analyzed the oxygen and carbon isotope compositions of nine ecologically diverse, sympatric taxa from Morea Estate, Mpumalanga Province, South Africa. These data show that the Morea Estate faunivores are depleted in 18O compared to herbivores, and among the herbivores, frequent drinkers are relatively depleted in 18O. While more research is needed to address the mechanisms for and universality of these patterns, these results show oxygen isotope analysis to be a promising avenue of paleoecological research.
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
(13)C/^(12)C ratios have been determined for plant tissue from 104 species representing 60 families. Higher plants fall into two categories, those with low δ_(PDB1) ^(13)C values (-24 to -34‰) and those with high δ ^(13)C values (-6 to -19‰). Algae have δ^(13)C values of -12 to -23‰. Photosynthetic fractionation leading to such values is discussed.
Article
Environmental factors, particularly climatic fluctuations; are widely viewed as important controls on the path of evolution. The broad coincidence of two adaptive transitions in hominid evolution with major climatic milestones supports models in which these evolutionary shifts are climatically driven. In the first, the origin of the Hominidae is tied to the Messinian desiccation of the Mediterranean. A second, more convincing case, involves the origin of the genus Homo and the first appearance of stone-tool technology, which occur in broad contemporaneity with the onset of Northern Hemisphere glaciation in the Pliocene. Detailed analysis, however, encounters difficulties in tying large-scale forcing phenomena to the terrestrial evidence for hominid evolution, and in resolving the effects of interacting environmental factors. The influences of climate, tectonics, volcanism, and community evolution all act at varying scales, and are reflected in different ways in the geologic record. Current research is tying detailed studies from the African continent to records of global change, and to better understanding of the interactive effects of various environmental factors with human evolution.
Chapter
As is the case for carbon, the study of stable hydrogen and oxygen isotopes in plant matter has its origins in the field of geochemistry. Geochemists for some time have been interested in using stable hydrogen and oxygen isotope ratios in fossil plant matter to determine climate during the formation of the plant matter in question. They reasoned that since the oxygen and hydrogen isotope ratios of water available for incorporation into plant biomass is influenced by climate, then the hydrogen and oxygen isotope ratios of plant matter should also be determined by climate. To determine climate, it would only be a question of deciphering the isotopic fractionation steps from water entering the roots to cellulose synthesized in the leaves.
Article
The carbon. and oxygen isotope composition of carbonate in enamel hydroxylapatite can provide information on photosynthetic pathways of plants at the base of food webs, and on hydrological conditions. Retrieval of palaeoenvironmental information from isotopic composition of vertebrate fossils is complicated by potential diagenetic overprinting. In this study alteration has been assessed by examining the extent to which expected biological carbon and oxygen isotope patterns are disrupted in fossils of species whose diets cart be independently predicted by other criteria. The biological patterns used are 1) the differences in carbon, isotope composition between grazers and browsers, and 2) the differences in oxygen isotope composition between hippopotamus and terrestrial herbivores. Results obtained on, enamel samples from Tighenif (Algeria, approximate to 700,000 yr), Melka-Kunture (Ethiopia, 0.7-1.5 myr), and Anabo Koma (Djibouti, approximate to 1.6 myr) suggest that in vivo carbon and oxygen isotope compositions are preserved in most cases. Moreover, in all three regions, modern, patterns of C-3 versus C-4 grass dominance were present within the Pleistocene.
Article
Indications are present in the dentition of prehominids that the dentition as a whole was being reduced. The reduction processes fit in well with what is known of reduction in euhominid dentitions, and the latter reduction appears simply to be a continuation of that started in the pre hominid group. The reduction process proceeds in different directions on either side of the first permanent molar, being from back to front in the molar row and front to back in the teeth anterior to M1. This has resulted in reduction of the size of all the elements of the dentition, but all have not been reduced to the same degree. The forces of mastication influence the architecture of the skull as a whole, but more especially that of the face. The diet of Paranthropus appears to have been primarily vegetarian, while that of Australopithecus seems to have been omnivorous and to have included a fair proportion of flesh. The resulting differences in strength and nature of the masticatory forces has affected the shape and structure of the face and braincase. There is no evidence that prehominids and euhominids could not synchronously occupy the same territory. On the contrary, the situation at Swartkrans (South Africa) and Sangiran (Java) indicates clearly that this did occur.
Article
Dietary adaptations of early hominids are generally understood to have played a crucial role in hominid evolution. The dietary habits of Australopithecus robustus are of special interest because the robust masticatory apparatus and characteristic dental features point to a distinctive dietary niche. Suggestions have ranged anywhere between carnivory and specialist herbivory, but current consensus has focused mainly on small hard items within the context of a vegetarian diet, and more particularly, frugivory. Few studies have challenged this perspective, although the results of a recent Sr/Ca study of A. robustus at Swartkrans were found to be inconsistent with herbivory. Here we address the question of A. robustus diet using 13C/12C ratio analysis of structural carbonate in tooth enamel, which has been shown to retain biogenic isotopic composition over long periods, contra earlier arguments based on bone apatite. Results for A. robustus, compared with other fauna from Swartkrans, show a mixed diet including both C3 and C4 foods. Since the C4 contribution must derive from consumption of grass or grazing animals, the data do not support either a specialist frugivorous or graminivorous niche for A. robustus; rather, they suggest a more generalized or omnivorous diet.
Article
The applicability of rapid and precise laser probe analysis of tooth enamel for {delta}{sup 18}O has been verified, and the method has been applied to different modern herbivores in East Africa. Sampling and pretreatment procedures involve initial bleaching and grinding of enamel to <75 {mu}m, and elimination of adsorbed water and organic compounds with BrF{sub 5}. Typical analytical reproducibilities for 0.5-2 mg samples are {+-}0.08{per_thousand} ({+-} 1{sigma}). Chemical and spectroscopic characterization of pretreated but unanalyzed samples show no alteration compared to fresh enamel. Solid reaction products are nearly pure CaF{sub 2} with little evidence for residual O{sub 2}. Because laser probe fluorination extracts oxygen from all sites in the apatite structure (phosphate, structural carbonate, and hydroxyl), only unaltered tooth enamel ( >95% apatite) can be analyzed reliably. Different East African herbivores exhibit previously unsuspected compositional differences. Average enamel {delta}{sup 18}O values (V-SMOW) are approximately: 25{per_thousand} (goat). 27{per_thousand} (oryx), 28{per_thousand} (dikdik and zebra), 29{per_thousand} (topi), 30{per_thousand} (gerenuk), and 32{per_thousand} (gazelle). These compositions differ from generalized theoretical models, but are broadly consistent with expected isotope effects associated with differences in how much each animal (a) drinks, (b) eats C3 vs. C4 plants, and (c) pants vs. sweats. Consideration of diet, water turnover. and animal physiology will allow the most accurate interpretation of ancient teeth and targeting of environmentally-sensitive animals in paleoclimate studies. 66 refs., 2 figs., 2 tabs.
Article
¹³C/¹²C ratios have been determined for plant tissue from 104 species representing 60 families. Higher plants fall into two categories, those with low δPDBI¹³C values (—24 to —34‰) and those with high δ ¹³C values (—6 to —19‰). Algae have δ ¹³C values of —12 to —23‰. Photosynthetic fractionation leading to such values is discussed.
Article
The presence of remains of Australopithecus africanus in the sediments of the Makapansgat limeworks has provoked numberous attempts to reconstruct the palaeoenvironment of the valley. New palynological evidence from a conformable section shows that there were major fluctuations of vegetation, and therefore climate, before and during the appearance of A. africanus at this site. The evidence suggests that the preferred habitat of the animal was forest or forest margin.
Article
Sympatric populations of lowland gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in the Lopé Reserve in central Gabon consumed insects at similar average frequencies over a 7-year period (30% versus 31% feces contained insect remains). Data came mostly from fecal analysis supplemented by observation and trail evidence. The weaver ant (Oecophylla longinoda) was the species eaten most frequently by both gorillas and chimpanzees. Other species of insects wore eaten but there was virtually no overlap: Chimpanzees used tools to eat Apis bees (and their honey) and two large species of ants; gorillas ate three species of small ants. Thus, despite their shared habitat, the esources utilized were not identical as gorillas do not show the tool-use “technology” of chimpanzees. The frequency of insect-eating by both species of ape varied seasonally and between years but in different ways. This variation did not seem to be related to the ratio of fruit to foliage in their diets. Gorillas of all age-classes ate insects at similar rates. Comparisons with insectivory by other populations of gorillas indicate differences exist. Mountain gorillas (Gorilla g. beringei) in the Virunga Volcanoes, Rwanda, consume thousands of invertebrates daily, eating them inadvertently with handfuls of herbaceous foods but they deliberately ingest insect-foods only rarely. Lowland gorillas at Lopé habitually ate social insects, and their selective processing of herbaceous foods probably minimizes inadvertent consumption of other invertebrates. Gorillas at Belinga in northeastern Gabon, 250 km from Lop6, ate social insects at similar rates but ignored weaver ants in favor of Cubitermes sulcifrons, a small species of termite that occurs at Lopé but was not eaten by gorillas. This indicates that local traditions similar to those reported for chimpanzees also exist amongst populations of gorillas. © 1992 Wiley-Liss, Inc.
Article
The allometric relationships between canine base area, first molar and summed molar crown area, and the glabella–opisthocranion distance, and the direct allometric relationships between canine and molar size have been established in five primate taxa. Separate sex and combined sex ‘intraspecific’, and ‘interspecific’ regression and ‘best fit’ allometry coefficients were computed. This analysis showed that for any increase in glabella–opisthocranion length, the rate of increase in canine size exceeds the rate of increase in molar area, and ‘best fit’ solutions indicate that canine base area is positively allometric when related directly to molar crown area. These results were compared with data available for the ‘gracile’ australopithecine, A. africanus, and two ‘robust’ australopithecine taxa, A. boisei and A. robustus. The differences in canine and molar size which occur between the ‘gracile’ taxon and the two ‘robust’ taxa do not correspond to any of the trends in the comparative allometric models. Data on glabella–opisthocranion length for the fossils, meagre though they are, show that while the proportional increase in molar crown area between the taxa corresponds to comparative allometry models, the reduced canine size in the ‘robust’ taxa is against comparative allometric trends. These results indicate that, at least in terms of canine/molar proportions, the differences between the ‘gracile’ and ‘robust’ australopithecines are not merely allometric and may indicate significant dietary or behavioural differences.
Article
Analyses of more than 1000 samples of soils, plants and bones of many species from a temperate woodland environment confirm the ubiquity of biopurification processes in which Ba/Ca and Sr/Ca decrease with increasing trophic position. This study reveals that differences among Ba/Ca and Sr/Ca ratios in soils and plants themselves are comparable to or greater than differences due to biopurification and preclude the use of these ratios for the quantitative assessment of dietary plant/meat ratios. The data also reveal that much of this variation at the base of the food web is removed at higher trophic positions through the extraordinary effectiveness of bone in providing a long-term statistical average of diet composition. This reduction in variation effects a pronounced correlation between Ba/Ca and Sr/Ca at higher levels of biopurification such that, given either Ba/Ca or Sr/Ca, a strong constraint can be placed upon the other ratio. This provides a tool for directly assessing whether measured Ba/Ca and Sr/Ca ratios are biological or reflect substantial post-mortem alteration.
Article
The oxygen isotopic composition of phosphate (δ18Op) and structural carbonate (δ18Oc) of hydroxylapatite was determined in 31 bone and tooth samples of modern mammals from different countries. These two variables are highly correlate (r2 = 0.98) and the calculated best fit of linear regression is very similar to the equation calculated from the phosphate and carbonate palaeotemperature equations [1,2]. According to previous measurements [3–6] on fossils of different ages from different areas it seems quite improbable to find isotopically altered skeletal remains showing a good correlation between δ18Op and δ18Oc, as is the case with modern samples. It therefore seems possible, at least in some cases, to use these measurements for monitoring fossil bone and tooth diagenetic alteration. When a set of points lie on the equilibrium line or close to it, the δ18O values could be considered close to the original values. In contrast, when the points lie to the left or to the right of this line this probably means that the values are diagenetically modified, due to interaction with meteoric water or18O-enriched water, respectively.
Article
Elemental analyses of mammalian bone (e.g., strontium-calcium ratios, or Sr/Ca) distinguish between herbivores and carnivores; however, the relationships among herbivores are unclear. To study this question, a modern faunal sample from the Nagupande Tsetse Control Area (Zambezi drainage, Northwestern Zimbabwe) was used. This collection has the advantage of well-established geographical controls in addition to a varied fauna, which includes both bovids and suids. The grazing/browsing dietary status of each species was ascertained by means of isotopic analysis of carbon. Clear differences were seen in the δ13C of grazing and browsing animals; a specialized grazer was found to have significantly lower Sr/Ca than less specialized grazers and browsers. In this study it was also possible to examine differences in Sr/Ca by sex; female warthogs were found to have significantly lower Sr/Ca than males. The variation in certain animal groups was found to be abnormal. Implications for reconstruction of prehistoric human diets using trace-element techniques are discussed.
Article
A reconstruction of the Makapansgat Valley when it was occupied by Australopithecus africanus , approximately 3 mya, indicates very different conditions from those prevailing today. Higher rainfall, thick, fertile, alkaline soils and moderate relief supported significant patches of sub-tropical forest and thick bush rather than savannah. Taphonomic considerations, particularly concerning the bone collecting agents and the numbers of australopithecine remains, suggest that sub-tropical forest was the hominins' preferred habitat rather than grassland or bushveld, and the adaptations of these animals were therefore fitted to a forest habitat. The Makapan specimens are the oldest A. africanus fossils, and as material from younger sites does not show the same forest habitat, there is an indication of a hominin trend away from forest dwelling with time and subsequent speciation events.
Article
A model relating relative size of the posterior teeth to diet is suggested for forest and savanna primates and Homo. Relative tooth size is calculated for the South African gracile australopithecine sample using posterior maxillary area sums and size estimates based on four limb bones. A number of limbs were shown to be non-hominid. Comparisons show the South African gracile sample apparently adapted to a very heavily masticated diet with relative tooth size significantly greater than any living hominoid. Periodic intensive utilization of grains and roots combined with scavenged animal protein are suggested as the most likely dietary reconstruction.
Article
Variations in the natural abundance of 18O and 2H in plant cellulose are influenced by the isotopic composition of the water directly involved in metabolism—the metabolic water fraction. The isotopic distinction between the metabolic source water and total tissue water must reflect the formation of isotopic gradients within the tissue that are influenced by the rate of water turnover, by properties of the water conducting system and by environmental conditions. It seems that the 18O abundance in the metabolic water is conserved in cellulose with a relatively constant isotope effect. The relationship of the 2H abundance between metabolic water and cellulose is more complex. Hydrogen incorporated into photosynthetic products during primary reduction steps is highly depleted in 2H. However, a large proportion of these hydrogens are subsequently replaced by exchange with water, leading to 2H enrichment during heterotrophic metabolism. Deciphering the oxygen isotope ratio of cellulose could help in providing insights into the carbon and oxygen fluxes exchanged between plants and the atmosphere. This is because the 18O abundance in cellulose records the 18O abundance in the metabolic water, which in turn, controls the oxygen isotopic signatures of the CO2 and O2 released by plants into the atmosphere. The hydrogen isotope effects associated with carbohydrate metabolism provide insights into the autotrophic state of a plant tissue. This is because the hydrogen isotope ratio of carbohydrates must reflect the net effects of the two opposing isotope effects associated with photosynthesis and heterotrophic metabolism.
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 isotope enrichment ɛ* of 13C between tooth enamel of large ruminant mammals and their diet is 14.1 ± 0.5‰. This value was obtained by analyzing both the dental enamel of a variety of wild and captive mammals and the vegetation that comprised their foodstuffs. This isotope enrichment factor applies to a wide variety of ruminant mammals. Non-ruminant ungulates have a similar isotope enrichment, although our data cannot determine if it is significantly different. We also found a 13C isotope enrichment ɛ* of 3.1 ± 0.7‰ for horn relative to diet, and 11.1 ± 0.8‰ for enamel relative to horn for ruminant mammals. Tooth enamel is a faithful recorder of diet. Its isotopic composition can be used to track changes in the isotopic composition of the atmosphere, determine the fraction of C3 or C4 biomass in diets of modern or fossil mammals, distinguish between mammals using different subpathways of C4 photosynthesis,and identify those mammals whose diet is derived from closed-canopy habitats.
Article
The habitat of the chimpanzees of Mt. Assirik, in the Parc National du Niokolo-Koba, Senegal, is described in terms of rainfall, temperature and vegetation. The results are compared with those collected at five other sites of study elsewhere in Africa. Mt. Assirik is the driest site at which chimpanzees have been studied, in terms of annual rainfall, proportion of dry months, and number of rainy days. Mt. Assirik is also the hottest such site: the coolest mean maximum temperature at Mt. Assirik exceeds the hottest such temperature at any other site. Mt. Assirik is the only site where chimpanzees have been studied in which the majority of vegetation is grassland. Forest consitutes less than 3% of the surface area. In summary, Mt. Assirik presents a truly open savanna habitat and is thus unique amongst sites where chimpanzees have been studied. These results are compared with data from a tropical foraging human society, the !Kung San of southern Africa. The !Kung San's habitat is drier on most (but not all) criteria, but Mt. Assirik is hotter. The climate and vegetation of Mt. Assirik strikingly resemble those reconstructed for the Plio-Pleistocene in eastern Africa. This suggests that the chimpanzees of Mt. Assirik provide a useful model for inferring the processes of adaptation in early hominids.
Article
Previous study of the strontium calcium ratio (Sr/Ca) of robust australopithecine skeletons from the Transvaal site of Swartkrans indicated that this Pleistocene hominid was an omnivore, suggesting that models for niche differentiation amongst contemporaneous hominids based on trophic level (i.e. Homo sp. = omnivore vs. A. robustus = herbivore) may be incorrect. In this study, we report that relatively elevated Sr/Ca is found in Homo sp. when compared to Australopithecus robustus skeletons from Swartkrans (ca. 1·8 ma BP). Examination of 87 Sr/86Sr in the same skeletons reduces the possibility that the result is due to different substrate sources of Sr. Foods with elevated Sr/Ca in the general area of Swartkrans are mainly geophytes, suggesting that the early Homo niche may have included relatively intensive exploitation of underground plant resources.
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
Biopurification factors for Ca with respect to Sr, Ba, and natural, uncontaminated Pb were measured for different nutrient-consumer pairs in a remote subalpine ecosystem. The factor for Sr is expressed as: (nutrient St/Ca) ÷ (consumer Sr/Ca). Similar expressions were used for Ba/Ca and Pb/Ca. It was found that Ca was biopurified of Sr 3-fold, of Ba 16-fold, and of Pb 100-fold in going from rock to sedge leaves. In going from sedge leaf to vole, Ca was biopurified of Sr 4-fold, of Ba 8-fold, and of Pb 16-fold. In going from meadow vole to pine marten, Ca was biopurified of Sr 6-fold, of Ba 7-fold, and of Pb 1.1-fold. Similar ranges of values for these factors were obtained for detrital and amphibian food chains. Fluxes of industrial lead entering the ecosystem as precipitation and dry deposition were measured and it was found that 40% of the lead in soil humus and soil moisture, 82% of the lead in sedge leaves, 92% of the lead in vole, and 97% of the lead in marten was industrial. The natural skeletal Pb/Ca ratio in carnivores (4 × 10^(−8)) was determined by means of corrections for inputs of industrial lead, food chain relationships, and measured biopurification factors for the ecosystem studied. This represents a 1700-fold reduction of the average Pb/Ca ratio in igneous rocks at the earth's surface (6.4 × 10^(−5)) by the compounding of successive Pb biopurification factors in transferring Ca from rock to carnivore. The natural ratio is similar to the value of 6 × 10^(−8) observed for Pb/Ca in the bones of Peruvians who lived 2000 years ago but is 1/900th of the value of about 3.5 × 10^(−5) for the skeletal Pb/Ca ratio found in present day Americans. This study shows experimentally how the Ba/Ca ratio in average surface igneous rock (3 × 10^(−3)) has been reduced 800-fold through compounding of successive biopurification steps to provide the skeletal Ba/Ca ratio of about 4 × 10^(−6) observed in humans. It also provides biopurification factors for Sr and Ba among a number of nutrient-consumer pairs which anthropologists can use to delineate degrees of herbivory in diets of hominids within the last 10,000 years.
Article
Tooth enamel of nine Middle Miocene mammalian herbivores from Fort Ternan, Kenya, was analyzed for δ13C and δ18O. The δ18O values of the tooth enamel compared with pedogenic and diagenetic carbonate confirm the use of stable isotope analysis of fossil tooth enamel as a paleoenvironmental indicator. Furthermore, the δ18O of tooth enamel indicates differences in water sources between some of the mammals. The δ13C values of tooth enamel ranged from −8·6–−13·0‰ which is compatible with a pure C3diet, though the possibility of a small C4fraction in the diet of a few of the specimens sampled is not precluded. The carbon isotopic data do not support environmental reconstructions of a Serengeti-typed wooded grassland with a significant proportion of C4grasses. This study does not preclude the presence of C3grasses at Fort Ternan; it is possible that C3grasses could have had a wider geographic range if atmospheric CO2levels were higher than the present values.
Article
Strontium-calcium ratios (Sr/Ca) are normally reduced at higher trophic levels in foodwebs, due to discrimination against strontium in favour of calcium by animals. This phenomenon has not generally been applied to the study of fossil foodwebs and the diets of early hominids because of diagenetic changes which obscure or obliterate biological Sr/Ca. The examination of compartments of fossil apatite having differing solubility, however, is a promising method for independently measuring biological and diagenetic Sr/Ca. In this study, Sr/Ca in Member I fossils from the site of Swartkrans were examined using a solubility profile procedure. Sr/Ca relationships observed among Swartkrans fauna match those seen in modern African foodwebs, suggesting that biological Sr/Ca accounts for the observed variation.When specimens of the fossil hominid Australopithecus robustus were examined, Sr/Ca values were inconsistent with that of a root, rhizome or seed-eating herbivore, suggesting that the diet of this species was more diverse than previously believed, and almost certainly included the consumption of animal foods.
Article
A large set of δ13C values for both the organic (collagen) and inorganic (apatitic) components of bone and tooth is presented for southern African fauna. Equations are obtained to describe variation in the relationship between these two isotopic values (the “apatite-collagen spacing”) with trophic level, for herbivores, carnivores and omnivores respectively. The empirically derived equations are slightly different from earlier predictions, and the implications are discussed. Differences between apatite and collagen δ13C values in a sample of prehistoric human skeletons from the southwestern Cape coast are considered in the light of relationships derived from faunal data. Unexpectedly small isotopic differences seen in many of these skeletons may be attributable to the particular mix of marine and terrestrial components of their diets.
Article
Theoretical predictions and measured isotope variations indicate that diet and physiological adaptation have a significant impact on animals δ18O and cannot be ignored. A generalized model is therefore developed for the prediction of animal body water and phosphate δ18O to incorporate these factors quantitatively. Application of the model reproduces most published compositions and compositional trends for mammals and birds. A moderate dependence of animal δ18O on humidity is predicted for drought-tolerant animals, and the correlation between humidity and North American deer bone composition as corrected for local meteoric water is predicted within the scatter of the data. In contrast to an observed strong correlation between kangaroo δ18O and humidity (), the predicted humidity dependence is only 1.3 – 1.7‰/10% r.h., and it is inferred that drinking water in hot dry areas of Australia is enriched in 18O over rainwater. Differences in physiology and water turnover readily explain the observed differences in δ18O for several herbivore genera in East Africa, excepting antelopes. Antelope models are more sensitive to biological fractionations, and adjustments to the flux of transcutaneous water vapor within experimentally measured ranges allows their δ18O values to be matched. Models of the seasonal changes of forage composition for two regions with dissimilar climates show that significant seasonal variations in animal isotope composition are expected, and that animals with different physiologies and diets track climate differently. Analysis of different genera with disparate sensitivities to surface water and humidity will allow the most accurate quantification of past climate changes.
Article
Strontium and calcium have been measured in a range of plants and animals (both marine and terrestrial) from the southwestern Cape of South Africa as part of an investigation of modern and prehistoric foodwebs in the region. First, the meat of marine molluscs and crustaceans are shown to have Sr and Sr/Ca values comparable to those of terrestrial plants. Thus, the consumption of these marine foods in this region cannot produce the markedly elevated Sr levels seen in archaeological human skeletons from coastal sites; such levels are shown to be a diagenetic phenomenon. Second, reduction in Sr/Ca in higher trophic levels is seen only when predators are compared with their prey. However, individual herbivore or carnivore species cannot be taken to represent other animals in their respective trophic level. These data imply that Sr/Ca is inappropriate for determining meat intake in complex prehistoric human diets in this region. The technique may be more useful in examining specific prey-predator relationships, including those in the early hominid fossil record.