Papers by Tammy Buonasera
Journal of Archaeological Science, 2024
The enamel proteome includes a range of proteins that are well-preserved in archaeological settin... more The enamel proteome includes a range of proteins that are well-preserved in archaeological settings but have so far received less study than those associated with sex-estimation of enamel. We look beyond sex-specific sequencing of amelogenin to investigate the potential of several serum proteins, including immunoglobulin gamma (IgG), the major immunoglobulin found in blood serum, and C-reactive protein (CRP), which is associated with inflammatory response, to provide insight into the health and stresses experienced by individuals in the past. We apply this approach to enamel samples from Mission-Period ancestral Ohlone interred at Asistencia San Pedro y San Pablo (CA-SMA-71/H; n = 11). For comparison, we also examine enamel from historic-period European-Americans interred in the City Cemetery in San Francisco (n = 12), and extracted third molars from present-day military cadets (n = 8). Results indicate that IgG is elevated among individuals at the asistencia relative to samples from present-day military cadets, and historic City Cemetery individuals (ANOVA with post-hoc Tukey Kramer tests, p < .02). Further, the inflammatory protein CRP, normally expressed at much lower levels than IgG, was present in 55% (6 of 11) of the asistencia samples, and in 17% (2 of 12) of the historic City Cemetery samples, but was not detected in enamel samples from present-day military cadets. While more studies are needed, we argue that the difference in IgG could reflect higher levels of chronic diseases such as tuberculosis among Ohlone living within the Mission system, and the presence of measurable amounts of CRP could relate to higher degrees of physical, social, and emotional stresses. To our knowledge, this is the first paleoproteomic study of immune proteins in tooth enamel. The ability to track immune responses during tooth formation could provide valuable and high-resolution information on ancient health and disease at the level of the individual over archaeological time-scales.
Scientific Reports, 2020
Sex estimation of skeletons is fundamental to many archaeological studies. currently, three appro... more Sex estimation of skeletons is fundamental to many archaeological studies. currently, three approaches are available to estimate sex-osteology, genomics, or proteomics, but little is known about the relative reliability of these methods in applied settings. We present matching osteological, shotgun-genomic, and proteomic data to estimate the sex of 55 individuals, each with an independent radiocarbon date between 2,440 and 100 cal BP, from two ancestral Ohlone sites in Central California. Sex estimation was possible in 100% of this burial sample using proteomics, in 91% using genomics, and in 51% using osteology. Agreement between the methods was high, however conflicts did occur. Genomic sex estimates were 100% consistent with proteomic and osteological estimates when DNA reads were above 100,000 total sequences. However, more than half the samples had DNA read numbers below this threshold, producing high rates of conflict with osteological and proteomic data where nine out of twenty conditional DNA sex estimates conflicted with proteomics. While the DNA signal decreased by an order of magnitude in the older burial samples, there was no decrease in proteomic signal. We conclude that proteomics provides an important complement to osteological and shotgun-genomic sex estimation. Biological sex plays an important role in the human experience, correlating to lifespan, reproduction, and a wide range of other biological factors 1-5. Sex and gender are also fundamental in structuring an array of cultural behaviors, including residence patterns, kinship, economic roles, and identity construction and expression 6-9. How sex interacts with gender and these particular issues is not static and can vary in detail across societies and over time 10-12. It is not surprising that sex is one of the most basic and important measures in bioarchaeological and forensic analyses. Typically, osteological features are used to estimate sex of skeletal remains, and the most widely used marker is the morphology of the os coxae 13-16. However, appropriate markers are not always sufficiently expressed or preserved to estimate sex using morphological criteria 17. A lack of sexually-dimorphic markers is especially acute for skeletons of infants and children who have not undergone puberty. Mortuary practices, such as cremation or secondary burial in charnel houses, can also can impose limitations on the utility of osteological sex estimates 18. The advent of DNA sequencing made it possible to use skeletal remains to estimate the sex of very young individuals ; it also expanded sex estimations for fragmentary, pathological, and degraded skeletal materials 19-21. More recently, development of massively parallel DNA sequencing greatly improved genome coverage in archaeological samples 22-25. In addition to providing detailed genetic information, this allows biological sex to be estimated from shotgun sequencing data 25-27. These approaches were an improvement over earlier PCR-based marker open
Human Biology, 2023
Síi Túupentak (CA-SCA-565/H) is a late precontact ancestral Ohlone village and cemetery site in c... more Síi Túupentak (CA-SCA-565/H) is a late precontact ancestral Ohlone village and cemetery site in central California (ca. 540-145 cal. BP). Integration of proteomic, genomic, and osteological analyses provided highly confident biological sex estimates for remains of most individuals at this site (65 of 76) spanning all age groups-from perinatal infants to aged adults. The comprehensive nature of the data allowed us to generate sex-specific Kaplan-Meyer survivorship curves for this burial population of sedentary hunter-gatherers. As was common among societies pre-dating modern western medicine and antibiotics, infant mortality was high for both males and females. However, male infants (from birth to 5 years of age) appear to have died at nearly twice the rate of female infants (10 of 33 males versus 5 of 32 females) and had a mean age of survival at birth of only 19 years, compared to 30 years for females. The difference in male and female survival was statistically significant when compared by a log-rank test (p =.005). Compared to survival curves for other societies pre-dating modern western medicine and antibiotics, including American-era historical deaths recorded for a cemetery in San Francisco, this bias is larger than might be expected. We suspect the pattern of sex-biased infant mortality at Síi Túupentak could relate to an intrinsic survival advantage for female infants, combined with extrinsic factors such as environmental pathogens, nutritional stress, and gendered differences in weaning patterns detected through stable isotope analyses. Using isotopic data on weaning ages and ethnographic accounts of gendered foraging activities, we focus on the potential role of sex-biased differences in weaning patterns and highlight potential demographic and social implications. Broader application of proteomic and genomic sex estimation would allow sex-biased differences in nutrition and health, as well as social and cultural aspects of male and female life histories, to be compared across a wide range of archaeologically known hunter-gatherer societies.
Journal of Archaeological Science: Reports, 2023
Ash and black char samples from seven combustion features at CA-ALA-11, an Early to Middle Period... more Ash and black char samples from seven combustion features at CA-ALA-11, an Early to Middle Period (ca. 2500 cal BCE to 585 cal CE) shellmound site on the San Francisco Bay shoreline, were analyzed for lipid, isotope, and phytolith content. Three features were intermingled with human burials and four were from nearby contexts not directly associated with human remains. Unlike more fragile biomolecules and floral remains, lipids and phytoliths can survive exposure to high temperatures. Together, these techniques supply independent and complementary lines of data for considering past cultural practices, local ecology, and post-depositional contributions. Our results shed light on the function and content of several combustion features, highlighting the untapped potential of such applications in the archaeology of California and elsewhere in North America. We focus on two combustion features with very different purposes. One appears to be the burnt remains of a basket (or possibly, a woven mat) coated with bitumen. This feature was associated with a burial and the basket or other woven object may have been burned as part of the funerary ceremony. Another feature, not directly associated with a burial, was composed of burned oyster shells and layered with leaves from a broadleaf tree—seemingly the remains of an ancient cooking feature for baking/steaming shellfish. Though small, this study demonstrates that analysis of sediments from combustion features can provide behavioral and ecological insights while avoiding destructive analysis of artifacts or human remains. We conclude with simple recommendations for integrating phytolith and lipid analysis of combustion features in future archaeological projects.
Journal of Archaeological Science
Abstract Biomolecular sex estimation promises to fill a major gap in the bioarchaeological record... more Abstract Biomolecular sex estimation promises to fill a major gap in the bioarchaeological record by providing estimates of biological sex for skeletal remains with degraded or ambiguous osteological sex-specific markers. Genomic and proteomic sex estimation, like all analytical methods, have limitations and require frameworks to address the problems of low signal samples and the inevitable conflicting results when other methods are used. Proteomic sex estimation is based on the detection of sex-chromosome specific amelogenin protein fragments in enamel using mass spectrometry. Enamel from male individuals contains amelogenin fragments from both the X-and Y-chromosome versions of amelogenin, and enamel from female individuals contains fragments from only the X-chromosome protein. The method is sensitive, robust, quantifiable and reproducible. Researchers have developed, and continue to develop, frameworks to address theoretical problems associated with low levels of detection and conflicting sex estimates that will inevitably occur when multiple methods are used on a sufficiently large dataset. Stamfelj reminds readers that structural variants of the Y-chromosome that delete the amelogenin gene have been detected in forensics and clinical casework. Since this phenomenon would also account for the absence of the AMELY protein in enamel it should therefore be mentioned as an alternative hypothesis by investigators, along with female sex and low peptide signals in mass spectrometry. In his meta-analysis Stamfelj concludes that this is an intrinsic limitation of biomolecular sex estimation, particularly when examining South Asian populations, and should be incorporated in standard analytical sex estimation frameworks. In this comment, we test this assertion by examining the occurrence of AMELY deletion in the systematically sampled, high coverage, large scale, and well-curated populations of the 1000 Genomes Project and Exome Sequencing Project. When using SNP loci in the open reading frame of AMELY, structural deletion was not detected in either project. Confident probabilities of occurrence with associated intervals cannot be determined from null values. We conclude from this that, for now, AMELY deletion should have no bearing on routine biomolecular sex estimation.
Journal of Archaeological Method and Theory, 2019
Molecular and isotopic analysis of sediments from archaeological combustion features is a relativ... more Molecular and isotopic analysis of sediments from archaeological combustion features is a relatively new area of study. Applications can inform us about ancient pyro-technologies and patterns of animal exploitation in a wide range of human contexts, but may be particularly informative with regard to ancient hunter-gatherers. Our analyses of sediments from experimental bone and wood fires, and from controlled laboratory heating sequences, provide fine-grained data on the formation and location of biomarkers from pyrolyzed animal fats in hearths. Integrating microstratigraphic, molecular and isotopic data can improve recognition of bone fires in archaeological contexts, perhaps even where bone preservation is poor. Experimental bone fires produced an upper layer of calcined bone above a thin layer of tarry-black amorphous material coating mineral sediments. Mineral sediments beneath the black layer showed little alteration but high lipid content. Sampling for molecular and isotopic analysis should target the black layer as the bulk of pyrolyzed biomarkers are located here and stable isotope values are less affected than in the overlying layer of ash or calcined bone. The combined presence of certain symmetric and slightly asymmetric saturated long-chain ketones (14-nonacosanone, 16-hentriacontanone, 16-tritriacontanone, and 18-pentatriacontanone), especially together with heptadecane (C17 n-alkane), are molecular indicators of the thermal degradation of terrestrial animal fat. Formation and relative dominance of these molecules in hearth sediments relates to the initial prevalence of specific precursor fatty acids and can provide broad separations between sources. We suggest that separations could be further supported and expanded by combining stable isotope analysis of the same compounds.
Journal of Archaeological Science, 2015
It is often assumed that use-surfaces on informal or expedient milling tools were formed strictly... more It is often assumed that use-surfaces on informal or expedient milling tools were formed strictly through use. Informal or expedient milling tools lack clear evidence of exterior shaping and are often associated with short-term occupations or temporary, task-specific sites. Here, a simple model of technological intensification outlined in Bettinger et al. (2006) is adapted to predict minimum use times necessary to profit from time spent improving the use-surface of milling tools. The costs and benefits of making and using improved milling surfaces for two types of raw material (sandstone and granite) are compared using experimentally derived estimates of grinding rates and manufacturing costs. Experiments indicate that shaping a milling surface increases seed-grinding efficiency. Modeling these data along with manufacturing costs predicts that manufacturing effort should be expected sooner than often assumed—in fact, little more than one and a half hours of seed grinding are necessary to profit from time spent manufacturing a shallow basin in sandstone. It also predicts that sandstone should be selected over granite for short-term seed grinding due to its ease of shaping. These results imply that there are many cases where mobile hunter-gatherers who processed seed resources could have reduced their overall handling time by selecting certain materials and investing time in shaping milling surfaces. This highlights the need for greater attention to physical evidence of manufacturing among expedient milling tools. Documenting raw material selection and degree of manufacturing effort expended on such tools can increase the visibility of gendered economic decisions among prehistoric hunter-gatherers.
Journal of Anthropological Archaeology, 2013
The archaeological record of central California contains a rich variety of ground stone milling t... more The archaeological record of central California contains a rich variety of ground stone milling tools—from highly expedient cobble tools to large ornate mortars and finely finished pestles more than half a meter in length. Historical trends in research objectives, along with assumptions about the entirely mundane character of ground stone tools, have caused much of the variability and many “extra-utilitarian” aspects of these artifacts to be overlooked. This study analyzed grave-associated ground stone from the southern San Francisco Bay Area and employed use-wear analysis (macroscopic and microscopic) and morphological comparisons to investigate potential distinctions in form, manufacturing effort, use, and association over approximately 6000 years of prehistory. Ground stone morphologies, patterns of use-wear, and the way that ground stone was interred with people changed between the earliest and the latest periods analyzed in this study. During the Late Holocene, ground stone underwent a diversification of form and perhaps purpose. An overtly symbolic dimension associated with mortars and pestles seems to emerge with the addition of highly formalized and expensive flower-pot mortars, very long shaped pestles, and additional embellishments such as shell bead appliqué and painted designs. Large, costly, highly formalized, and embellished mortars exist alongside smaller, less costly, less formalized milling tools. Archaeological and ethnographic evidence supports the inferred association of certain mortars with feasting and ritual activities. Differences in the representation of some of these forms in male and female graves may reflect changes in the roles of women and men in community ritual and politics.► Ground stone milling tools were integral to economic and social transformations in central California prehistory. ► Synchronic and diachronic variability exists among mortuary associated ground stone artifacts. ► Archaeological and ethnographic evidence supports the association of certain mortars with feasting and ritual activities. ► Changes in the status of women and men, and roles in community ritual and politics are explored. ► Ground stone tools offer an important and often overlooked source of data for considering social changes in prehistory.
Science Advances, 2020
Sexual division of labor with females as gatherers and males as hunters is a major empirical regu... more Sexual division of labor with females as gatherers and males as hunters is a major empirical regularity of hunter-gatherer ethnography, suggesting an ancestral behavioral pattern. We present an archeological discovery and meta-analysis that challenge the man-the-hunter hypothesis. Excavations at the Andean highland site of Wilamaya Patjxa reveal a 9000-year-old human burial (WMP6) associated with a hunting toolkit of stone projectile points and animal processing tools. Osteological, proteomic, and isotopic analyses indicate that this early hunter was a young adult female who subsisted on terrestrial plants and animals. Analysis of Late Pleistocene and Early Holocene burial practices throughout the Americas situate WMP6 as the earliest and most secure hunter burial in a sample that includes 10 other females in statistical parity with early male hunter burials. The findings are consistent with nongendered labor practices in which early hunter-gatherer females were big-game hunters.
Analysis of preserved lipids from archaeological sites in northwest Alaska indicates hunters expl... more Analysis of preserved lipids from archaeological sites in northwest Alaska indicates hunters exploited marine animal resources as early as 4500 years ago. Bone preservation at early prehistoric sites in northern Alaska is generally poor, contributing to uncertainty about the economic orientation of the earliest Arctic Small Tool tradition (ASTt) hunters. We used lipid analysis and compound specific stable isotope analysis (CSIA) of burned, cemented sand and organic residue features to detect the use of marine versus terrestrial animals at several coastal sites in northwest Alaska. Though the sample size for this initial study was small (n = 5), comparisons among samples from early ASTt, and later Norton and Thule sites indicate all three groups made use of marine animals for food and/or fuel. Recently obtained radiocarbon dates suggest ASTt hunters settled coastal regions of Alaska prior to moving inland to exploit
terrestrial habitats. Our results provide empirical evidence that suggests the economy of the early ASTt population included a maritime component. In Arctic settings where bone preservation is poor, lipid analysis of cemented sand and organic residue features can provide an effective alternative for detecting the use and processing of marine versus terrestrial animals.
Bedrock features represent various economic, social, and symbolic aspects of past societies, but ... more Bedrock features represent various economic, social, and symbolic aspects of past societies, but have historically received little study, particularly in North America. Fortunately, new techniques for analyzing spatial configurations, use-wear, and organic residues are beginning to unlock more of the interpretive potential of these features. Though preliminary in nature, the present study contributes to this trend by documenting an application of lipid analysis to bedrock features in a dry rockshelter. Results of this initial application indicate that bedrock features in dry rockshelters may provide especially favorable conditions for the preservation and interpretation of ancient organic residues. Abundant lipids, comparable to concentrations present in some pottery sherds, were extracted from a bedrock grinding surface at Gila Cliff dwellings National Monument and analyzed using gas chromatography-mass spectrometry. Though the lipids were highly oxidized, degradation products indicative of former unsaturated fatty acids were retained. Comparisons to experimentally aged residues, and absence of a known biomarker for maize, indicate that the bulk of the lipids preserved in the milling surface probably derive from processing an oily nut or seed resource, and not from processing maize. Substantially lower amounts of lipids were recovered from a small, blackened cupule. It is hypothesized that some portion of the lipids in the blackened cupule was deposited from condensed smoke of cooking and heating fires in the caves. Potential for the preservation of organic residues in similar sheltered bedrock contexts is discussed, and a practical method for sampling bedrock features in the field is described.
Journal of California and Great Basin Anthropology, 2019
In California archaeology, and in many contexts world-wide, few data exist to compare functional ... more In California archaeology, and in many contexts world-wide, few data exist to compare functional differences among traditional ground-stone mortar designs. This study used a series of replicative grinding experiments to compare small-seed and acorn/nut processing rates among three mortar designs (shallow cup, deep bowl, and deep conical) and two grinding slab designs (unshaped flat slab, and shallow basin) that were common, in various combinations, in many plant-based hunting and gathering societies. Experimental processing rates are reported and considered in reference to manufacturing costs, mobility, and resource use. Results indicate some unexpected relationships between deep bowl and deep conical mortars and seed processing. In particular, large mortars with deep, broad interiors are highly effective tools for producing flour from both small wild seeds and acorns. Deep conical mortars are also good for acorn processing, but perform poorly for processing small seeds into flour. As expected, shallow mortars are the least productive, but also the least expensive, grinding tools. Large mortars with broad, bowl-shaped interiors would have been excellent tools for long-term use in settings where multiple types of plant resources were processed into finer particles. In California, this interior morphology is shared among so-called flower-pot mortars as well as large bowl mortars. Despite their superior performance, steep costs of manufacturing, including the transport of suitable raw materials, may have limited the contexts of use and the ownership of these types of mortars.
The Society for Archaeological Sciences Bulletin, 2013
Shiny grooved rock surfaces found in archaeological sites are common across west Texas and the So... more Shiny grooved rock surfaces found in archaeological sites are common across west Texas and the Southwest (U.S.). In most cases they are cursorily described, with very little in terms of detailed characterization and analysis. Interpretations regarding the meaning of the grooves include fertility rituals and functional use (e.g., bone tool or axe polishing), while the formation of the shiny surface has been attributed to lichen, foot or hand traffic, and hide or plant processing. In the Lower Pecos region (Texas), such remains are common in rockshelters. In several cases, there is only one such surface at a prominent location within the site, commonly associated with bedrock features (mortars, slicks, etc.). We used Structure from Motion (SfM) to document, characterize and analyze more than 700 elongated grooves and incisions concentrated on one shiny surface, at Skiles Shelter. All were mapped, and the larger grooves were also measured and studied using macro-lens and microscope photos. The direction and sequence of engraving were reconstructed, with evidence for most grooves and incisions being earlier than the shiny cover. The incorporation of small pits with the engravings was established. Although organic residues were retrieved from several bedrock features at the site, no distinct chemical signature was identified from the shiny surface. We could not ascertain the origin of the shiny crust, and based on other works and our observations we suggest that hand or foot traffic, hide working and plant fiber processing are the most likely explanations.
Journal of Archaeological Science, 2007
Analysis of absorbed organic molecules in ground stone could provide a valuable means to study re... more Analysis of absorbed organic molecules in ground stone could provide a valuable means to study resource use and processing in antiquity. The following study analyzed extracts from the surfaces of several central California milling tools to assess whether organic residues remained from prehistoric resource processing. It also sought to determine which source identification methods are likely to be successful at providing information about the type, or even the specific identify, of resources that were processed. Lipids (primarily fatty acids) were analyzed using GC-MS and the presence of phenolic compounds was assessed with UV-Vis spectroscopy. Milling surfaces were compared to previously broken surfaces
from the same tool with the assumption that both surfaces had been exposed to similar post-depositional conditions. Results supported the presence of ancient residues in milling tools. A higher concentration of fatty acids was recovered from milling surfaces than paired broken surfaces.
Furthermore, measurable amounts of azelaic acid (an oxidation product of some unsaturated fatty acids) were present in most milling surfaces, but not in broken surfaces. However, results also indicated that environmentally absorbed lipids formed a significant portion of the total lipid
content. Thus, it is suggested that future analyses employ a biomarker approach, rather than criteria based on ratios of common fatty acids, to identify sources of organic residues in prehistoric milling tools.
Journal of Archaeological Science, 2005
Although lipid analysis of archaeological residues has been utilized for almost three decades, it... more Although lipid analysis of archaeological residues has been utilized for almost three decades, it has rarely been applied to archaeological materials other than pottery. A 2001 study used lipid analysis of burned rocks (sandstone) and ground stone tools to interpret subsistence change at a south Texas site (M.J. Quigg, M.E. Malainey, R. Przybylski, G. Monks, No bones about it: using lipid analysis of burned rock and groundstone residues to examine Late Archaic subsistence practices in South Texas, Plains Anthropologist 46 ). If such applications are reliable, insight into past subsistence practices could be greatly enhanced. The following study tested whether measurable amounts of lipids could be extracted from burned rocks (andesite) from a central California site and the ability of fatty acid analysis to reliably interpret those extracts. While results indicate that some of the burned rocks may contain lipids absorbed from cooking activities, lipids were also recovered from off-site rocks. Before reliable interpretations of culturally introduced lipids can be made, more thorough study of the types and amounts of lipids present in rocks due to natural processes is necessary.
Analysis of preserved lipids from archaeological sites in northwest Alaska indicates hunters expl... more Analysis of preserved lipids from archaeological sites in northwest Alaska indicates hunters exploited
marine animal resources as early as 4500 years ago. Bone preservation at early prehistoric sites in
northern Alaska is generally poor, contributing to uncertainty about the economic orientation of the
earliest Arctic Small Tool tradition (ASTt) hunters. We used lipid analysis and compound specific stable
isotope analysis (CSIA) of burned, cemented sand and organic residue features to detect the use of marine
versus terrestrial animals at several coastal sites in northwest Alaska. Though the sample size for this
initial study was small (n ¼ 5), comparisons among samples from early ASTt, and later Norton and Thule
sites indicate all three groups made use of marine animals for food and/or fuel. Recently obtained
radiocarbon dates suggest ASTt hunters settled coastal regions of Alaska prior to moving inland to exploit
terrestrial habitats. Our results provide empirical evidence that suggests the economy of the early ASTt
population included a maritime component. In Arctic settings where bone preservation is poor, lipid
analysis of cemented sand and organic residue features can provide an effective alternative for detecting
the use and processing of marine versus terrestrial animals.
Links to web pages by Tammy Buonasera
http://cead.ucdavis.edu/ground-stone-use-wear.html
The collection of photomicrographs and photographs posted here is intended to facilitate data sha... more The collection of photomicrographs and photographs posted here is intended to facilitate data sharing and comparisons between different experimental use-wear programs. The images can also function as a teaching aid, or as a supplemental resource for use-wear analysis of ground stone. For more information on the images and the experiments that produced the wear, visit the CEAD website. http://cead.ucdavis.edu/ground-stone-use-wear.html
Volunteers processed Indian ricegrass (Oryzopsis hymenoides) seeds into flour using five differen... more Volunteers processed Indian ricegrass (Oryzopsis hymenoides) seeds into flour using five different types of basalt milling tools. A future session will do the same using duplicate sets made from sandstone. These are the first of several seed processing sessions that will be hosted in the LTT over the next year.
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Papers by Tammy Buonasera
terrestrial habitats. Our results provide empirical evidence that suggests the economy of the early ASTt population included a maritime component. In Arctic settings where bone preservation is poor, lipid analysis of cemented sand and organic residue features can provide an effective alternative for detecting the use and processing of marine versus terrestrial animals.
from the same tool with the assumption that both surfaces had been exposed to similar post-depositional conditions. Results supported the presence of ancient residues in milling tools. A higher concentration of fatty acids was recovered from milling surfaces than paired broken surfaces.
Furthermore, measurable amounts of azelaic acid (an oxidation product of some unsaturated fatty acids) were present in most milling surfaces, but not in broken surfaces. However, results also indicated that environmentally absorbed lipids formed a significant portion of the total lipid
content. Thus, it is suggested that future analyses employ a biomarker approach, rather than criteria based on ratios of common fatty acids, to identify sources of organic residues in prehistoric milling tools.
marine animal resources as early as 4500 years ago. Bone preservation at early prehistoric sites in
northern Alaska is generally poor, contributing to uncertainty about the economic orientation of the
earliest Arctic Small Tool tradition (ASTt) hunters. We used lipid analysis and compound specific stable
isotope analysis (CSIA) of burned, cemented sand and organic residue features to detect the use of marine
versus terrestrial animals at several coastal sites in northwest Alaska. Though the sample size for this
initial study was small (n ¼ 5), comparisons among samples from early ASTt, and later Norton and Thule
sites indicate all three groups made use of marine animals for food and/or fuel. Recently obtained
radiocarbon dates suggest ASTt hunters settled coastal regions of Alaska prior to moving inland to exploit
terrestrial habitats. Our results provide empirical evidence that suggests the economy of the early ASTt
population included a maritime component. In Arctic settings where bone preservation is poor, lipid
analysis of cemented sand and organic residue features can provide an effective alternative for detecting
the use and processing of marine versus terrestrial animals.
Links to web pages by Tammy Buonasera
terrestrial habitats. Our results provide empirical evidence that suggests the economy of the early ASTt population included a maritime component. In Arctic settings where bone preservation is poor, lipid analysis of cemented sand and organic residue features can provide an effective alternative for detecting the use and processing of marine versus terrestrial animals.
from the same tool with the assumption that both surfaces had been exposed to similar post-depositional conditions. Results supported the presence of ancient residues in milling tools. A higher concentration of fatty acids was recovered from milling surfaces than paired broken surfaces.
Furthermore, measurable amounts of azelaic acid (an oxidation product of some unsaturated fatty acids) were present in most milling surfaces, but not in broken surfaces. However, results also indicated that environmentally absorbed lipids formed a significant portion of the total lipid
content. Thus, it is suggested that future analyses employ a biomarker approach, rather than criteria based on ratios of common fatty acids, to identify sources of organic residues in prehistoric milling tools.
marine animal resources as early as 4500 years ago. Bone preservation at early prehistoric sites in
northern Alaska is generally poor, contributing to uncertainty about the economic orientation of the
earliest Arctic Small Tool tradition (ASTt) hunters. We used lipid analysis and compound specific stable
isotope analysis (CSIA) of burned, cemented sand and organic residue features to detect the use of marine
versus terrestrial animals at several coastal sites in northwest Alaska. Though the sample size for this
initial study was small (n ¼ 5), comparisons among samples from early ASTt, and later Norton and Thule
sites indicate all three groups made use of marine animals for food and/or fuel. Recently obtained
radiocarbon dates suggest ASTt hunters settled coastal regions of Alaska prior to moving inland to exploit
terrestrial habitats. Our results provide empirical evidence that suggests the economy of the early ASTt
population included a maritime component. In Arctic settings where bone preservation is poor, lipid
analysis of cemented sand and organic residue features can provide an effective alternative for detecting
the use and processing of marine versus terrestrial animals.