Dogs as Analogs in Stable Isotope-Based Human Paleodietary Reconstructions: A Review and Considerations for Future Use

In contexts where human remains are scarce, poorly preserved, or otherwise unavailable for stable isotope-based paleodietary reconstruction, dog bone collagen as well as other tissues may provide a suitable proxy material for addressing questions relating to human dietary practices. Inferences drawn from applications of this ??canine surrogacy approach?? (CSA) must be made with caution to ensure the accuracy and transparency of conclusions. This paper shows that CSA applications are essentially analogical inferences which can be divided into two groups that provide specific types of information and may require different levels of substantiation. A framework of three categories of factors is outlined to aid in establishing positive, negative, and neutral elements of comparison of dog and human diets. CSA applications may benefit from explicitly detailing the type and nature of the analogical reasoning employed and from providing a systematic assessment of the degree to which stable isotope values of dogs and humans under comparison are thought to be like, unlike, or of unknown likeness.     

A canine surrogacy approach to human paleodietary bone chemistry: past development and future directions

When archaeological human remains are absent or otherwise unavailable for bone chemistry-based paleodietary reconstructions, dog remains may provide an appropriate surrogate material for approximating ancient human diet. This “canine surrogacy approach” (CSA) has developed over the past thirty years and is becoming more common in archaeological science literature. A dearth of continued innovation in CSA applications as well as recent criticisms of its feasibility may reflect the absence of a cohesive overview of the approach’s development, its underlying analogical nature, as well as variation and inconsistency in the ways it has been applied. Considering the CSA’s invaluable potential to partially circumvent the destructive analysis of human remains, thereby addressing the increasingly recognized concerns of indigenous groups, such considerations would be timely and germane. Recent research has characterized the role of analogy in CSA applications and devised a framework for making CSA interpretations (Guiry J Archaeol Method Theory 19(3):351–376, 2012a, b). In contrast to, and complementing that work, this paper provides an outline of the CSA’s inception and evolution with particular emphasis on identifying the impetuses for, and trends in, its development. In addition to clarifying the CSA’s origin as well as where and why it is applied today, this review provides an opportunity to identify future directions for productive methodological innovation.     

Inferring Human Behaviors from Isotopic Analyses of Rat Diet: a Critical Review and Historical Application

Rat (Rattus spp.) bone collagen stable isotope values are often assumed to reflect an average of food stuffs that were available to archaeological populations. This paper considers the feasibility of using stable isotope evidence from rat remains as a source of proxy information for human food-related social, economic, and sensorial behaviors. First, a literature review of archaeological and modern ecological rat isotope work reveals that, while rat dietary signatures are often a reasonable proxy for human food waste, they will not always record an unbiased average of foods which are available in a given environment. Second, an overview of ethological, biological, and environmental factors that can influence rat diets is given from the perspective of archaeological bone chemistry, to help identify factors that require explicit and critical consideration when rat stable isotope data is taken as a proxy for human food-related behaviors. Finally, rat stable isotope values are considered to provide new evidence about the social and economic responses of an important historical English fishing community at Ferryland (CgAf-02) to conflict and political turmoil at the turn of the eighteenth century. These results also highlight how information on rat diets can provide a counterpoint to other common faunal isotope approaches that focus on dogs and pigs as a proxy for human dietary behaviors.     

Studies on Amerindian dogs: Taxonomic analysis of canid crania from the Northern Plains

Archaeological investigation of the economic role of domestic versus wild canids among late prehistoric and historic villagers in the Northern Plains has long been hindered by difficulties in reliably distinguishing between remains of different species, especially dogs (Canis familiaris) and wolves (Canis lupus). Taxonomic confusion is the result of deliberate human selection for large, strong dogs for use as draft animals, and occasional but probably consistent hybridization between dogs and wolves. Discriminant analysis is used to help identify 33 archaeological canid crania from the Northern Plains, many of which are taxonomically confusing. Reference samples for classification of these specimens consist of six groups of modern or archaeological dog, wolf and coyote (Canis latrans) crania from North America. Thirteen measurements are used. Analysis indicates that, relative to wolves, the dogs tend to have proportionally wide posterior cranial vaults, short snouts and palates, steeply rising foreheads, and small teeth. Although convincing evidence for dog—wolf hybrid specimens from recent Plains archaeological contexts is lacking, the identification of such specimens probably has little practical significance with regard to canid domestication in general. Compared to dogs, a greater proportion of specimens identified as wolves exhibit evidence of butchering.     

EFFECTS OF DIFFERENT SAMPLE PREPARATION METHODS ON STABLE CARBON AND OXYGEN ISOTOPE VALUES OF BONE APATITE: A COMPARISON OF TWO TREATMENT PROTOCOLS*

Researchers have long debated the appropriateness of stable isotope analysis of bone apatite to reconstruct the diets of ancient animals. The debate has centred, in part, on diagenesis of bone mineral from interaction with the burial environment. A number of acetic acid treatments are used to remove diagenetic carbonates from samples; however, less is known on how different protocols alter stable isotope values. We compare two common acetic acid solution treatments (0.1 M versus 1.0 M-buffered) to examine the effects on carbon and oxygen isotope values and Fourier transform infrared spectroscopy (FTIR) spectra in human bone from different burial contexts. Results indicate that both treatments have a similar effect on isotope values and FTIR spectra in bone apatite.     

Stable isotope analysis of dog,fox, and human diets at a Late Holocene Chumash village (CA-SRI-2) on Santa Rosa Island,California

Stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope analyses of dog (Canis familiaris), island fox (Urocyon littoralis), and human bone collagen from CA-SRI-2 (AD 130–1830) on Santa Rosa Island, California provide a proxy of diet and the relationships between humans and these animals. Carbon isotopic signatures indicate that Native Americans and their dogs at CA-SRI-2 subsisted almost exclusively on marine resources, while the island fox ate primarily terrestrial foods. Nitrogen isotopes and archaeofaunal remains indicate that humans and dogs also ate higher trophic level foods, including finfishes, marine mammals, and seabirds with smaller amounts of shellfish. The CA-SRI-2 island foxes appear to have eaten higher amounts of terrestrial foods, similar to the diets observed in modern fox populations. These data generally confirm the commensal relationship assumed to exist between domesticated dogs and people, but the carbon isotopic composition of dogs is enriched ∼2‰ compared to humans. We hypothesize that the difference in carbon isotopes between dogs and humans may have resulted from a higher consumption of C3 plants with lower δ¹³C values by humans, or less likely from the ingestion by dogs of significant amounts of bone collagen, which is enriched by ∼4‰ over associated muscle.     

A further consideration of neolithic dogs with special reference to a skeleton from Grime's Graves (Norfolk), England

The complete skull and skeleton of a dog were recently excavated from the neolithic flint mines at Grime's Graves in Norfolk. As very few complete skeletons of dogs have been found from neolithic contexts in Britain a detailed metrical comparison was made between the Grime's Graves specimen and dog skeletons of comparable antiquity and completeness from Easton Down and Windmill Hill in Wiltshire.Implicit in the study of the dog from Grime's Graves was the need to date it precisely. As the skeleton could not be sacrificed for radiocarbon dating, closely associated antlers of Red deer (Cervus elaphus) were used for this purpose. The date of the Grime's Graves dog is compared with the dates for other dog remains from recently excavated neolithic sites in the British Isles.     

Stable isotopes and human diet in central western Argentina

Central western Argentina is the southern boundary of prehispanic maize in the archaeological record. This paper explores the stable isotope information from human bone (δ¹³C, from collagen and δ¹³C from apatite) and tooth (δ¹³C from enamel) samples in order to characterize the temporal and spatial trends of these isotopes and to understand them in terms of human diet. We analyzed 104 human individuals from the last 6000 years. Using the Kellner and Schoeninger (2007) model the results shows a high variation in human diet with few human individuals with a notably high significance of C₄ plants (probably maize) as an energy source and these samples have a chronology around ca. 1000 years BP. On the other hand a high variation in an individual’s dietary life history is shown by differences between δ¹³C collagen, apatite and enamel.     

A calf for all seasons? The potential of stable isotope analysis to investigate prehistoric husbandry practices

The Early Bronze Age barrows at Irthlingborough and Gayhurst in central England are notable for the large number of cattle (Bos taurus) remains associated with their human Beaker burials. Previous work using strontium isotope analysis has indicated that most of the cattle analysed, and one aurochs (Bos primigenius), were of local origin [Towers, J., Montgomery, J., Evans, J., Jay, M., Parker Pearson, M., 2010. An investigation of the origins of cattle and aurochs deposited in the Early Bronze Age barrows at Gayhurst and Irthlingborough. Journal of Archaeological Science 37, 508–515.]. In this study, stable isotope analysis of enamel and bone was carried out to investigate whether the mature cattle had experienced similar husbandry practices, climate and environment. Bulk carbon, nitrogen and sulphur isotope analysis of collagen suggested most were consuming similar sources of plant protein from environments probably local to the sites and this was supported by high resolution intra-enamel carbon isotope profiles. Oxygen isotope profiles indicated the aurochs and most of the cattle experienced similar climatic regimes: the only exception being an animal with a non-local strontium isotope ratio. However, a comparison of seasonality profiles of the local animals using estimated tooth formation times showed that there was no consistency in season of birth: the animals appeared to have been born throughout the year. Cattle can breed throughout the year but it requires considerable human effort and intervention to successfully overwinter young stock; it is therefore unlikely to have been carried out without good reason and benefit if winters were harsh. One reason is to ensure a continuous supply of milk. Measuring oxygen isotope profiles to identify year-round calving may thus be a potential indicator of dairying economies.     

Molecular and morphological analyses of avian eggshell excavated from a late thirteenth century earth oven

Using ancient DNA (aDNA) extracted from eggshell of the extinct moa (Aves: Dinornithiformes) we determined the species composition and number of eggs found in a late thirteenth century earth oven feature at Wairau Bar (South Island, New Zealand) – one of New Zealand’s most significant archaeological sites. Mitochondrial and nuclear DNA signatures confirmed this oven feature contained fragments of at least 31 moa eggs, representing three moa genera: Emeus; Euryapteryx; Dinornis. We demonstrate through the genetic identification of 127 moa eggshell fragments that thickness is an unreliable character for species assignment. We also present a protocol for assessing the preservation likelihood of DNA in burnt eggshell. This is useful because eggshell fragments found in archaeological contexts have often been thermally modified, and heat significantly increases DNA fragmentation. Eggshell is widely used in radiocarbon dating and stable isotope research, this study showcases how aDNA can also add to our knowledge of eggshell in both archaeological and palaeoecological contexts.     

Stable carbon and nitrogen isotope analysis on human remains from the Early Mesolithic site of La Vergne (Charente-Maritime,France)

We report here the results of stable carbon and nitrogen isotope analysis of human and faunal remains from La Vergne (Charente-Maritime, western France), a rare Early Mesolithic burial site (ca. 8500–8000 cal BC). The results for nine humans (average δ¹³C = −19.3‰; δ¹⁵N = 9.4‰) indicate a strongly terrestrial diet, dominated by animal protein, with the possibility of, at best, a slight contribution of marine-derived protein. Given lower sea-levels in the early Holocene, the site would have been some 60–80 km from the sea at the time of its use; nevertheless, contacts with the coast are shown by the presence of numerous marine shell beads in the graves. In the light of the stable isotope results, it is suggested here that such contacts most likely took the form of exchange with coastal communities whose remains now lie underwater.     

Pig diet in medieval York: carbon and nitrogen stable isotopes

This study investigates bone stable isotopes from pigs from medieval York, to characterise the pigs' diet and to explore their contribution to isotopic values from contemporary human bones. Pig bones from the Swinegate (N?=?9) and Coppergate (N?=?14) sites were used for carbon and nitrogen stable isotope analysis to test the hypothesis that the majority of pigs in medieval York were yard-kept and fed on scraps and fish waste, elevating their nitrogen ratios. The results show that the Swinegate and Coppergate pigs gave nitrogen isotope values similar to contemporary sheep and therefore that animal protein made little or no dietary contribution. One sample showed C and N results consistent with more animal protein in the diet, and we propose that this could have been a yard-kept pig consuming human refuse. The majority of the data indicate that the pigs were eating a largely herbivorous diet and that pigs in medieval York may have been raised in rural or woodland locations rather than in the city.     

Early Neolithic diets at Baijia,Wei River valley,China: stable carbon and nitrogen isotope analysis of human and faunal remains

Stable carbon and nitrogen isotope values are presented for faunal and human bone collagen from Baijia, in the Wei River valley region of Shaanxi Province, China. The remains have a calibrated age range of ca. 5709–5389 BC, and correspond with the early Neolithic Laoguantai Period. Stable isotopic results indicate that human diets included millet and probably aquatic foods such as fish and shellfish. Bovid samples are tentatively identified as water buffalo, and have a mean δ¹³C value of −14.6‰, which reflects some millet consumption. Whether bovids were grazing on wild millet, or had diets directly influenced by humans, is not known. The single Sus sample from Baijia had a diet dominated by C3 plants and is thus unlikely to have been a domesticated animal. Overall, the stable isotope results presented here conform to the current concept that the people of the Laoguantai culture were millet farmers, who had subsistence strategies that included hunted wild foods.     

Beyond the grave: variability in Neolithic diets in Southern Germany?

Carbon and nitrogen stable isotope analyses were undertaken on human and faunal remains from two Neolithic sites in Southern Germany; the LBK settlement at Herxheim and the middle Neolithic cemetery at Trebur. Stable isotope data were used to reconstruct the diets of individuals buried at these sites and to look at dietary variation between groups classified by their sex, age, grave goods and cultural affiliation. Overall there was surprisingly little variation in the diet between the groups, as described by the stable isotope analysis, despite significant differences in the composition of grave goods. Also surprising, considering the archaeological evidence for extensive grain cultivation in this region during the Neolithic, was that the majority of individuals had δ¹⁵N values consistent with the consumption of significant amounts of animal protein.     

Mixed Livelihood Society in Iin Hamina – a Case Study of Medieval Diet in the Northern Ostrobothnia,Finland

A stable isotope investigation of a large Medieval population buried in Iin Hamina, northern Finland, has been used to reconstruct palaeodiet. Iin Hamina is situated approximately 30?km away from the modern city Oulu, in close proximity to the Bothnian Bay coast and the river Ii. The material used in this study is human skeletal material from an Iin Hamina cemetery dated as 15 to 17th centuries AD and animal bones excavated in Northern Ostrobothnia from pre-industrial contexts. Stable isotope analysis of well-preserved collagen indicate that both freshwater and marine fish was the dominant protein source for the people buried at the Iin Hamina cemetery.     

Determining Olmec maize use through bulk stable carbon isotope analysis

Bulk stable carbon isotope analysis on absorbed organic residues in ceramics can be an effective method for discerning patterns of maize use when the ceramics come from relatively uniform archaeological contexts. The bulk stable carbon isotope method is faster and less costly than the more commonly used compound-specific stable carbon isotope analysis. Moreover, the bulk stable carbon isotope method can determine the presence of C4 plant carbon in samples in which organic compounds have degraded. Bulk stable carbon isotope analysis was used to discern patterns of maize (Zea mays mays) use among a sample of 24 ceramic sherds from an Early Franco Period feasting deposit (ca. cal 650 B.C.) at the Olmec site of San Andrés, La Venta, Tabasco, Mexico. A comparison of the δ 13C results of different categories of ceramics showed that proportionally more maize was used in luxury beverage service wares than in utilitarian vessels, suggesting that maize-based beverages were prominent in this probable elite feasting episode.     

What's in a bone? Recent advances in archaeological bone chemistry

This paper focuses on advances in archaeological bone chemistry since 1989. At that time studies generally shifted from development and application of techniques in bone chemistry to more experimental approaches. In stable isotope studies, controlled feeding experiments have been carried out to determine the routing of various dietary components into bone tissues. Biological apatite has been added to collagen as a tissue of study for stable carbon isotope analysis, providing the ability to study much older remains. Other elements have been added such as hydrogen for the study of paleoclimate and oxygen and strontium isotopes to study life history. Trace element studies have focused on methods of detecting and controlling for diagenesis, and barium has been added to the list of useful dietary indicators. Attempts to extract DNA from archaeological bone have been successful, however, this field is still in its early stages in terms of applications to understanding prehistoric biological relationships.     

The Movement and Exchange of Dogs in the Prehistoric Caribbean: An Isotopic Investigation

This study explores the feasibility of using strontium isotope (⁸⁷Sr/⁸⁶Sr) analyses of enamel from domestic dogs (Canis familiaris) to investigate networks of exchange in the prehistoric Circum‐Caribbean. Dog teeth were obtained from burial and domestic contexts from two prehistoric sites (Anse à la Gourde and Morel) on Grande‐Terre, Guadeloupe (Lesser Antilles). Strontium isotope results were compared with local biosphere ⁸⁷Sr/⁸⁶Sr data at the scale of the site, island and archipelago. The isotope results indicate both local and nonlocal origins with three dogs (30%) identified as nonlocal (one from Anse à la Gourde and two from Morel). The variance in ⁸⁷Sr/⁸⁶Sr ratios of the nonlocal dog teeth is consistent with diverse multiple origins external to the island of Grande‐Terre but consistent with origins from other islands of the Lesser Antilles. The diverse origins of the nonlocal dog samples indicate that the prehistoric circulation of dogs occurred at multiple scales from regional to long distance. Significantly, the ⁸⁷Sr/⁸⁶Sr ratios of some of the dog teeth are comparable with values of nonlocal humans at Anse à la Gourde determined in previous studies. It is possible that these comparable ⁸⁷Sr/⁸⁶Sr ratios result from similar natal origins, for example if individuals were migrating to Guadeloupe with dogs. The results of this study contribute to an ongoing regional investigation of the economic, social and political roles of animals and animal remains and the multiscalar networks of prehistoric mobility and exchange in the Circum‐Caribbean region. Copyright © 2013 John Wiley & Sons, Ltd.     

Stable isotope investigations of charred barley (Hordeum vulgare) and wheat (Triticum spelta) grains from Danebury Hillfort: implications for palaeodietary reconstructions

Palaeodietary studies typically focus on the analysis of bone collagen due to the limited availability of plant remains. Isotopic analysis of plant remains, however, allow for a more extensive consideration of the contribution of plants to the human diet and can potentially provide information about the environment in which the crops were grown. This paper reports the results of carbon and nitrogen isotope analyses performed on charred barley and wheat grains recovered from pits within Danebury Iron Age hillfort. To the best of our knowledge, this is the first Iron Age site in Britain from which charred grains have been isotopically analysed. Our results suggest that cereals found at the hillfort were grown in several different environmental contexts. The isotope data demonstrate that the herbivores were not consuming a diet primarily based on grains as the δ¹⁵N values of the grains are very similar to those of the herbivores. Palaeodietary investigations typically assume that humans eating plant protein only would have the same δ¹⁵N value as the local herbivores. This assumption is clearly invalid at Danebury, where the humans and animals appear to have consumed either different parts of the same plants or different plants. Researchers typically interpret high differences between human and animal δ¹⁵N values as indicative of diets high in animal protein, however where major plant resources have δ¹⁵N values similar to those of the herbivores our ability to distinguish between plant and animal sources of protein in the diet is limited. Our research has demonstrated that whenever possible it is desirable to measure the isotopic signatures of potential major plant resources in order to understand past subsistence strategies.     

Isotopic evidence for diet in the Middle Chulmun period: a case study from the Tongsamdong shell midden,Korea

This article presents the first isotopic investigation of human and animal bone remains from the Middle Chulmun (3500–2000 BC) period in southeastern Korea. We have obtained a single human and associated faunal stable carbon and nitrogen isotope results from the Tongsamdong site, a coastal shell midden. Despite the discovery of domesticated plants and the existence of large amounts of terrestrial mammal bones from the shell midden, the human and dogs we measured were heavily dependent on marine protein resources for their lives. Although our stable isotope results are based on a small number of individuals due to the lack of human remains at this period, isotopic evidence suggests the possibility that Tongsamdong people in the Middle Chulmun period depended largely on marine protein resources. This isotopic evidence is consistent with the archaeological evidence from the site.