Lipid biomarkers and compound specific δ13C analysis indicate early development of a dual-economic system for the Arctic Small Tool tradition in northern Alaska

Abstract

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.

Chemical profiling of ancient hearths reveals recurrent salmon use in Ice Age Beringia

“…Food resources in hearths can also be difficult to discriminate because of the potential for admixture of fuel charcoal. Most previous studies have focused on the FA profiles, lipid biomarkers (13,14), and δ 13 C values of FAs from hearth residues (15,46). Our bulk δ 13 C values from all USR hearths were similar among all USR hearths (Fig.…”

Experimentally Derived Sedimentary, Molecular, and Isotopic Characteristics of Bone-Fueled Hearths

“…Organic residue studies of ancient hearth sediments date from at least the late 80s (March et al 1989;March 1999;Rottländer 1989Rottländer , 1991. However, the pace of this research is increasing as access to sensitive analytical instrumentation improves, techniques of organic residue analysis mature, and fire and cooking technologies are forefronted in human prehistory (Buonasera et al 2015;Choy et al 2016;García-Piquer et al 2018;Kedrowski et al 2009;Lejay et al 2016;Lucquin 2007Lucquin , 2016March 2013;March et al 2014;Prost et al 2011). Our intent here is not to provide an exhaustive historical review, but to discuss the current state of knowledge regarding molecular and isotopic identification of animal fats in hearths.…”

“…In a more recent Alaskan application, Buonasera et al (2015) used a combination of lipid biomarkers and δ 13 C values for two fatty acids to identify a marine source of burned, fat-encrusted sand from Arctic Small Tool tradition (ASTt), Norton, and Thule sites along the west coast of northern Alaska. Biomarkers targeted for analysis were the same as those used in the prior Heron et al (2010) study: ω-(o-alkylphenyl) alkanoic acids 18, 20, and 22 carbons long (products of pyrolysis), as well as certain isoprenoid fatty acids (non-pyrolytic biomarkers of aquatic organisms).…”

“…The present study is concerned with improving our ability to identify and locate inputs from animal fats in anthropogenic combustion structures using molecular analysis, compound specific stable isotope analysis (CSIA), and soil micromorphology. Combining molecular and isotopic analysis of sediments and pyrolyzed char from archaeological combustion features is a relatively new area of study (Buonasera et al 2015;Choy et al 2016;Heron et al 2010;March 2013;March et al 2014) and microcontextualized biomarker studies are rare (Sistiaga et al 2014). Applications have the potential to inform us about ancient pyro-technologies and patterns of animal exploitation in a wide range of human contexts, from traditional farming societies to Paleolithic hunter-gatherers.…”

Large mammal biomass predicts the changing distribution of hunter-gatherer settlements in mid-late Holocene Alaska

“…Our analysis shows they must have possessed a sophisticated maritime adaptation at the outset of their migration into Alaska and across the Arctic. A lack of preserved fauna and organic technology from coastal ASTt sites has generally hampered investigation of this point, but recent work along the Chukchi Coast in northwest Alaska has provided support of ASTt marine mammal exploitation at least by 4500 cal BP, evident in the form of preserved lipids encrusted in beach sands (Buonasera et al, 2015;Tremayne, 2015c).…”