Eric J. Guiry

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.

Mesolithic Dietary Heterogeneity on the European Atlantic Coastline: Stable Isotope Insights into Hunter-Gatherer Diet and Subsistence in the Sado Valley, Portugal

Stable carbon and nitrogen isotope data from the bone collagen of human remains excavated in the Sado Valley in the Alentejo region of Portugal provide evidence for the existence of two Mesolithic communities living in close proximity along the shores of an estuarine environment with significantly different diets. These findings add to the limited isotope paleodiet data set from this period in southern Europe and offer a valuable contribution to understandings of the wider European Mesolithic along the Atlantic coastline by (1) providing evidence of coastal Mesolithic hunter-gatherers with mainly terrestrial diets in Europe and (2) suggesting the presence of regional heterogeneity, at a small geographical scale, in subsistence choices among coastal Mesolithic groups. These results show the complexity of human subsistence adaptations in the European Mesolithic and have wider-reaching implications for understanding hunter-gatherer group interactions.

Effects of lipid extraction and ultrafiltration on stable carbon and nitrogen isotopic compositions of fish bone collagen.

RATIONALE Fish bone collagen isotopic measurements are increasingly important in palaeodietary and paleoenvironmental studies yet differences in the chemical and physical properties of fish relative to other vertebrate bones are rarely considered. Lipid content in fish bone, which can exceed 50%, may underlie the poor collagen integrity criteria typically observed in archaeological studies. METHODS We compare stable carbon and nitrogen isotopic and elemental compositions of bone collagen prepared using four different methods from a wide range of modern fish species to: (1) assess the extent to which lipid content influences bone collagen δ(13) C and δ(15) N values, and (2) evaluate the relative efficacy of chemical (2:1 chloroform/methanol) and physical (30 kDa ultrafilters) methods for removing lipids from bones. RESULTS Lower δ(13) C values were observed when the lipid content exceeded 5% of the initial bone mass. The lipid content did not influence the δ(15) N values. 30 kDa ultrafiltration, a common pretreatment for purifying archaeological collagen, removed fewer lipids and was associated with reduced collagen yields (37% loss) as well as altered amino acid compositions. In contrast, collagen prepared using a 2:1 chloroform/methanol lipid extraction step resulted in significantly improved collagen yields, elemental compositions, and isotopic measurements relative to a control treatment. CONCLUSIONS The chemical lipid extraction method (2:1 chloroform/methanol) performed significantly better than the physical lipid extraction method (30 kDa ultrafilters). Given the high quantities of lipids in fish bones we recommend the inclusion of a chemical lipid extraction step when isolating collagen from modern and archaeological fish bones. Copyright

The evolutionary history of dogs in the Americas

Lineage losses for mans best friend Dogs have been present in North America for at least 9000 years. To better understand how present-day breeds and populations reflect their introduction to the New World, Ní Leathlobhair et al. sequenced the mitochondrial and nuclear genomes of ancient dogs (see the Perspective by Goodman and Karlsson). The earliest New World dogs were not domesticated from North American wolves but likely originated from a Siberian ancestor. Furthermore, these lineages date back to a common ancestor that coincides with the first human migrations across Beringia. This lineage appears to have been mostly replaced by dogs introduced by Europeans, with the primary extant lineage remaining as a canine transmissible venereal tumor. Science, this issue p. 81; see also p. 27 Ancient North American dogs survive primarily as a canine transmissible venereal tumor. Dogs were present in the Americas before the arrival of European colonists, but the origin and fate of these precontact dogs are largely unknown. We sequenced 71 mitochondrial and 7 nuclear genomes from ancient North American and Siberian dogs from time frames spanning ~9000 years. Our analysis indicates that American dogs were not derived from North American wolves. Instead, American dogs form a monophyletic lineage that likely originated in Siberia and dispersed into the Americas alongside people. After the arrival of Europeans, native American dogs almost completely disappeared, leaving a minimal genetic legacy in modern dog populations. The closest detectable extant lineage to precontact American dogs is the canine transmissible venereal tumor, a contagious cancer clone derived from an individual dog that lived up to 8000 years ago.

The Transition to Agriculture in South-Western Europe: New Isotopic Insights from Portugal's Atlantic Coast

Abstract For the past 15 years, a succession of stable isotope studies have documented the abrupt dietary transition from the Mesolithic to the Neolithic in Western and Northern Europe. Portugal, with its Late Mesolithic shell middens and burials apparently coexisting with the earliest Neolithic, further illustrates the nature of that transition. Individuals from Neolithic contexts there had significantly different diets to their Mesolithic counterparts. No evidence was found for a transitional phase between the marine-oriented Mesolithic subsistence regimes and the domesticated, terrestrial Neolithic diet. Two later Neolithic individuals, however, showed evidence for partial reliance on marine or aquatic foods. This raises questions about the possible persistence of marine dietary regimes beyond the Mesolithic period. This article is followed by a brief note by Mary Jackes and David Lubell.

Lake Ontario salmon ( Salmo salar ) were not migratory: A long-standing historical debate solved through stable isotope analysis

Lake Ontario once supported a large complex of Atlantic Salmon (Salmo salar) populations that became extinct prior to scientific study. Since the 1860s, research efforts to conserve and reintroduce a sustainable population of Atlantic Salmon have focused on determining whether Lake Ontario’s original salmon populations had migrated to the Atlantic Ocean as part of their lifecycle (anadromy), stayed in the lake year-round (potamodromy), or both. We used stable carbon, nitrogen, and sulfur isotope analyses of archaeological bones and historical museum-archived salmon scales to show that the original salmon populations from Lake Ontario completed their entire lifecycle without migrating to the Atlantic Ocean. With a time depth of more than 500 years, our findings provide a unique baseline with significant potential for informing modern restocking and conservation efforts.

Tar Trap: No Evidence of Domestic Dog Burial with “La Brea Woman”

We radiocarbon dated the domestic dog found associated with La Brea Woman at the Rancho La Brea tar pits (Los Angeles, CA) to determine the validity of this human–dog connection. The domestic dog yielded a radiocarbon age of 3125 ± 25 14C yr BP (3250–3400 cal yr BP) and La Brea Woman had a re-dated age of 9080 ± 15 14C yr BP (10,220–10,250 cal yr BP). This ∼7000-year offset dispels the hypothesis this was an intentional and ceremonial human–dog burial.

Anthropogenic changes to the Holocene nitrogen cycle in Ireland

Chemical signatures from Bronze Age animal bones show that prehistoric humans had a major impact on the nitrogen cycle in Ireland. Humans have always affected their ecosystems, but finding evidence for significant and lasting changes to preindustrial landscapes is rare. We report on human-caused changes to the nitrogen cycle in Ireland in the Bronze Age, associated with intensification of agriculture and animal husbandry that resulted in long-term changes to the nitrogen isotope values of animals (wild and domesticates) during the Holocene. Major changes to inputs and cycling of soil nitrogen occurred through deforestation, land clearance and management, and more intensive animal husbandry and cereal crop cultivation in the later Bronze Age; after this time, the Irish landscape took on its current form. Within the debate concerning the onset of the Anthropocene, our data suggest that human activity in Ireland was significant enough in the Bronze Age to have long-term impact, thereby marking a profound shift in the relationship between humans and their environment.

Dating archaeobotanical remains: a cautionary tale from Port au Choix, Newfoundland

Abstract In this paper we report on the first 14C dated archaeological seeds from the island of Newfoundland, Canada. Ninety-three archaeobotanical specimens were recovered from a midden deposit adjacent to a small dwelling at Point Riche (EeBi-20), a large Dorset Palaeoeskimo site near Port au Choix, northwestern Newfoundland. These remains were collected from a seemingly secure context within the midden, but AMS 14C testing of a sample of specimens produced modern 14C dates, indicating that the remains are intrusive to the Dorset occupation. While the majority of Newfoundland-based research assumes antiquity of archaeobotanical remains, we recommend using AMS 14C dating and other proxy data in future archaeobotanical studies to confirm antiquity prior to making interpretations regarding human–plant interactions.