paleomobility in the tiwanaku diaspora: biogeochemical analyses at rio muerto, moquegua, peru

Paleomobility in the Tiwanaku Diaspora:Biogeochemical Analyses at Rio Muerto,Moquegua, Peru

Kelly J. Knudson,1* Paul S. Goldstein,2* Allisen Dahlstedt,1 Andrew Somerville,2

and Margaret J. Schoeninger2

1Center for Bioarchaeological Research, School of Human Evolution and Social Change, Arizona State University,Tempe, AZ 852872Department of Anthropology, University of California at San Diego, La Jolla, CA 92093

KEY WORDS radiogenic strontium isotopes; oxygen isotopes; Middle Horizon

ABSTRACT Paleomobility has been a key element inthe study of the expansion of ancient states and empires,including the Tiwanaku polity of the South Central Andes(AD 500–1000). We present radiogenic strontium and oxy-gen isotope data from human burials from three ceme-teries in the Tiwanaku-affiliated Middle Horizonarchaeological site complex of Rio Muerto in the Moque-gua Valley of southern Peru. At Rio Muerto, ar-chaeological human enamel and bone values rangefrom 87Sr/86Sr 5 0.70657–0.72018, with a mean of87Sr/86Sr 5 0.70804 6 0.00207 (1r, n 5 55). For the subsetof samples analyzed for oxygen isotope values (n 5 48),the data ranges from d18Ocarbonate(VSMOW) 5 118.1 to127.0&. When contextualized with other lines ofarchaeological evidence, we interpret these data as evi-dence for an archaeological population in which themajority of individuals had “local” origins, and were likely

second-generation, or more, immigrants from the Tiwa-naku heartland in the altiplano. Based on detailed lifehistory data, we argue a smaller number of individualscame at different ages from various regions within theTiwanaku polity. We consider whether these individualswith isotopic values consistent with “nonlocal” geographicorigins could represent first-generation migrants, mar-riage exchange partners, or occupationally mobile herd-ers, traders or other travelers. By combining isotopic lifehistory studies with mortuary treatment data, we use aperson-centered migration history approach to state inte-gration and expansion. Isotopic analyses of paleomobilityat the Rio Muerto site complex contribute to the role ofdiversity in ancient states by demonstrating the range ofgeographic origins rather than simply colonists from theLake Titicaca Basin. Am J Phys Anthropol 000:000–000,2014. VC 2014 Wiley Periodicals, Inc.

Paleomobility, including migration and other types ofresidential mobility, is integral to understanding politi-cal expansion and integration in ancient states andempires. Using new advances in both theory (e.g., Gold-stein, 2005; Cabana and Clark, 2011) and method (e.g.,Bentley, 2006), scholars are elucidating the variability inpast political practices. Here, we investigate expansionand political integration in ancient states through aperson-centered migration history approach, focusing onthe Tiwanaku polity of the South Central Andes duringthe Middle Horizon period (AD 500–1000; Fig. 1). Usingnew archaeological and isotopic data from theTiwanaku-affiliated site complex of Rio Muerto, Peru,we examine variability in Tiwanaku expansion in theSouth Central Andes through reconstructing individuallife histories and paleomobility at both the levels of theindividual and the population.

We first discuss our theoretical perspective, includingmigrations and diasporic colonization in ancient states.We then provide a brief description of the uses of biogeo-chemistry to investigate paleomobility, describe thearchaeological context of Rio Muerto, Peru, and thenintroduce our materials and methods. Radiogenic stron-tium and oxygen isotope data from Rio Muerto, Peru arepresented to explore the relationship of its inhabitantsto the Tiwanaku capital located in the Lake TiticacaBasin of Peru and Bolivia, and other parts of the Tiwa-naku polity. We conclude with a discussion of paleomo-

bility at Rio Muerto, Peru, and its implications for ourunderstanding of diversity and mobility in the Tiwanakupolity and other ancient states through analyses at thelevel of the individual and the population.

DIASPORIC COLONIZATION IN THE ANDEANMIDDLE HORIZON

Scholars are increasingly investigating the variableways in which individuals and elite groups in prehistoricand historic states expanded their political and economicpower (e.g., Alcock et al., 2001; Goldstein, 2005; Stein,2005; Cabana and Clark, 2011). In the Andes, the social

Grant sponsor: Institute for Social Science Research, ArizonaState University; School of Human Evolution and Social Change,Arizona State University; Wenner Gren Foundation; HJ Heinz IIIFoundation; University of California at San Diego ArcheologicalField School.

*Correspondence to: Kelly J. Knudson. E-mail: [email protected] Paul S. Goldstein. E-mail: [email protected]

Received 25 November 2013; revised 7 July 2014; accepted 15July 2014

DOI: 10.1002/ajpa.22584Published online 00 Month 2014 in Wiley Online Library

(wileyonlinelibrary.com).

� 2014 WILEY PERIODICALS, INC.

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 00:00–00 (2014)

phenomena of migration, colonization and transhumanceare among the most important areas of research on theexpansion of complex societies. For example, in the InkaEmpire (AD 1400–1532), conquest by a relatively smallInka military presence was often followed by strategiccolonization in which the state moved subjugated groups

for imperial security and agricultural labor (e.g., Covey,2000; D’Altroy, 2002; Alconini, 2004; Wernke, 2006;McEwan, 2008; Ogburn et al., 2009; Meddens andSchreiber, 2010; Andrushko and Torres, 2011). However,archaeological evidence suggests a different pattern inthe Tiwanaku polity, where communities in the

Fig. 1. Map of the Rio Muerto site complex in the Moquegua Valley of southern Peru with sites discussed in the text. [Color fig-ure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

2 K.J. KNUDSON ET AL.

American Journal of Physical Anthropology

http://wileyonlinelibrary.com

altiplano, or high-altitude plain, directly colonized low-altitude agricultural regions (e.g., Kolata, 1993; Blom,2005; Goldstein, 2005; Janusek, 2008; Knudson, 2008;Stanish et al., 2010). Goldstein (2005) described thisform of state expansion through demographic coloniza-tion as “diasporic,” in that Tiwanaku-affiliated low-alti-tude colonies were large-scale, permanent andmultigenerational, and colonists’ social identities withspecific parent communities were strongly maintainedover the long term by continuity in cultural practices,marriage exchange, and actual or expected returnmigration (Goldstein, 2003, 2005; Baitzel, 2008; Baitzeland Goldstein, 2011). Additionally, in the diasporamodel, migration streams articulated with and weremaintained by their distinct parent communities, ratherthan a unitary state-directed colonization.

These archaeological interpretations of Tiwanaku colo-nization pose several testable paleomobility expectationsdrawn from studies of diasporas and colonization (e.g.,Clifford, 1994; Blom et al., 1998; Stein, 2005; Goldstein,2000, 2005, 2009). First, direct colonization must bedemonstrated by the presence of first-generationmigrants. Because the Tiwanaku colonies endured forhundreds of years, reproducing similar mortuary prac-tices and artifact styles for many generations of locallyborn descendants, it is challenging to identify the smallproportion of individuals likely to represent first-generation migrants from archaeological data alone.However, Knudson (2008) has demonstrated the pres-ence of first-generation altiplano migrants in severalTiwanaku-affiliated sites.

Secondly, a “diasporic” colonized region would beexpected to be “multiethnic”, with distinct enclaves com-posed of individuals from specific parent communitieswithin the larger Tiwanaku polity. If so, different sites,sectors or cemeteries in the colonized region would showevidence of distinct community identities. Conversely, asocially integrated program of initial colonization or abreakdown over time of strict identification with parentcommunities would be expected to show heterogeneity oforigin that crosscuts the entire colonized region.

Third, the ages and sexes of first-generation migrantscould reflect both the nature of migration and the waysin which Tiwanaku colonists reproduced their populationand social identities. While first-generation migrantswho arrived in the colonies during the first years of lifelikely represent a migration stream that included entirefamilies, first-generation migrants who arrived as adultsof reproductive age may reflect patterns of mateexchange between different Tiwanaku regions. If adultfirst-generation migrants were predominantly female ormale, it may be possible to investigate patrilocal ormatrilocal patterns of mate exchange.

Finally, individual life history data can demonstratemore complex patterns of mobility, including reversemigration or prolonged transhumance, as well as main-tenance of social identities over time. For example, indi-viduals who spent equal amounts of time in thighlandsand lowlands may represent a more mobile lifeway, per-haps involving occupational pastoralism, caravan trade,or sojourns at multiple locations for ritual, political, orother purposes. Because colonies can, and often do,reproduce the cultural practices and materials of thehomeland well past the second generation, archaeologyhas a limited ability to test expectations about paleomo-bility. Fortunately, an independent line of inquiry isavailable through biogeochemistry.

PALEOMOBILITY THROUGH BIOGEOCHEMISTRY

Radiogenic strontium and oxygen isotopes are com-monly used to investigate paleomobility, particularlyarchaeological human residential mobility (Evans et al.,2012; Knudson et al., 2012a; Price et al., 2012; Wright,2012). In radiogenic strontium isotope analysis, stron-tium substitutes for calcium in dental and skeletal ele-ment hydroxyapatite during development (Turekian andKulp, 1956). In archaeological human remains, 87Sr/86Srvalues in enamel and bone reflect the 87Sr/86Sr values inthe strontium in the food and water consumed andimbibed, which in turn reflect the 87Sr/86Sr values in thebioavailable strontium in the geologic region or region inwhich an individual lived during enamel and bone for-mation (Bentley, 2006). Unlike radiogenic strontium iso-tope analysis, which ultimately reflects bedrockvariability (Faure, 1991), oxygen isotope analysis utilizesenvironmental variability. Oxygen isotope values inmeteoric water (d18Ometeoric water) vary according to envi-ronmental factors including elevation, temperature,humidity, and latitude (Craig, 1961a; Dansgaard, 1964;Gat, 1996). At constant body temperature, the oxygenisotope values in hydroxyapatite carbonate (d18Ocarbonate)and phosphate (d18Ophosphate) reflect the oxygen isotopevalues in body water, which largely reflect the oxygenisotope values in imbibed water sources (Longinelli,1984; Luz et al., 1984). In addition to environmental var-iability, oxygen isotope data from enamel samples couldhave been influenced by the consumption of 18O-enriched breast milk before and during the weaning pro-cess (Herring et al., 1998; Wright and Schwarcz, 1998,1999; Wright et al., 2010).

BASELINE ISOTOPIC DATA FROM THE SOUTHCENTRAL ANDES

Radiogenic strontium isotope values

Andean isotopic variability ensures that we can useradiogenic strontium and oxygen isotopes to investigatepaleomobility (e.g., Knudson et al., In press). TheMoquegua Valley where Rio Muerto is located is in ageologic zone composed largely of late Cenozoic volcanicrocks such as andesites (Bellido et al., 1956). Late Ceno-zoic volcanic rocks from Arequipa, Peru exhibit a rangeof 87Sr/86Sr 5 0.7067–0.7079 (n 5 16; James, 1982), andandesites from the San Pedro and San Pablo volcanoesof northern Chile exhibit mean87Sr/86Sr 5 0.70653 6 0.00036 (1r, n 5 16; Francis et al.,1977). Similarly, exposed bedrock samples from lateCenozoic volcanic rocks in northern Chile exhibit mean87Sr/86Sr 5 0.70646 6 0.00020 (1r, n 5 8; Rogers andHawkesworth, 1989). In contrast, the radiogenic stron-tium isotope values in the Bolivian altiplano and theLake Titicaca Basin are much higher (Coudrain et al.,2002; Grove et al., 2003; Placzek et al., 2011), and reflectthe Paleozoic andesites, sandstones, red mudstones, andalluvial deposits (Argollo et al., 1996). For example, inLake Titicaca surface water, mean87Sr/86Sr 5 0.70834 6 0.00013 (1r, n 5 3; Grove et al.,2003) and 87Sr/86Sr 5 0.70834 (Coudrain et al., 2002).

Bioavailable 87Sr/86Sr values are often obtained frommodern and archaeological small mammal samples(Price et al., 2002; Bentley et al., 2004; Evans andTatham, 2004). Small mammal 87Sr/86Sr values from theSouth Central Andes generally reflect expected 87Sr/86Srvalues based on bedrock geology (Knudson and Price,

PALEOMOBILITY IN THE TIWANAKU DIASPORA 3


2007; Knudson, 2008; Conlee et al., 2009; Slovak et al.,2009; Knudson and Tung, 2011; Knudson et al., inpress). For example, bioavailable radiogenic strontiumisotope values in local modern small mammal samplesfrom Moquegua, Peru exhibit mean87Sr/86Sr 5 0.70625 6 0.00018 (1r, n 5 3; Knudson et al.,2004). In contrast, modern faunal samples exhibit mean87Sr/86Sr 5 0.70963 6 0.00028 (1r, n 5 8) in the northernaltiplano’s Lake Titicaca Basin (Knudson and Price,2007). Other regions in the South Central Andes thatwere used by the Tiwanaku polity include the Cocha-bamba Valley of Bolivia and the San Pedro de Atacamaoases of northern Chile, where local modern andarchaeological small mammal samples exhibit mean87Sr/86Sr 5 0.72148 6 0.00162 (1r, n 5 4; Lucas, 2012)and mean 87Sr/86Sr 5 0.70764 6 0.00013 (1r, n 5 3;Knudson and Price, 2007), respectively. Finally, in thesouthern altiplano near Lake Poop�o, modern faunalsamples exhibit higher radiogenic strontium isotope val-ues such as 87Sr/86Sr� 0.713 (Knudson et al., 2005).

Oxygen isotope values

Baseline oxygen isotope variability in the Andes isgenerally less well understood than radiogenic strontiumisotope variability. However, there are large differencesin precipitation patterns, elevation, temperature, andamounts of glacial ice in the altiplano and lower-altituderegions (Messerli et al., 1993; Wolfe et al., 2001; N�u~nezet al., 2002; Magiligan et al., 2008). Groundwater andsurface water samples from the Moquegua Valley rangefrom approximately d18Ometeoric water (VSMOW) 5 211.0 to28.0&, while spring water exhibits much higher valuesof approximately d18Ometeoric water (VSMOW) 5 22.0&(Magiligan et al., 2008). In contrast, precipitation in thealtiplano city of La Paz, Bolivia exhibited d18Ometeoric

water (VSMOW) 5 213.3 to 210.8& between 1996 and 2001and oxygen isotope values in Lake Titicaca Basin surfacewater were d18Ometeoric water (VSMOW) 5 217.6 to 212.6&(IAEA/WMO, 2006).

There are a number of factors that affect oxygen iso-tope values in drinking water in the Andes (Knudson,2009). Rather than generating baseline data from precip-itation values, it is preferable to collect samples fromactual drinking water sources used in the past (Buzonet al., 2011; Webb et al., 2013). For the inhabitants ofthe Rio Muerto site complex, the principal irrigation anddrinking water sources were most likely surface waterbrought by canals from the river and from mid-valleywells, where d18Ometeoric water (VSMOW) 5 211.0 to 28.0&in surface water samples collected in 2007 (Magiliganet al., 2008). However, Rio Muerto is also located nearseveral downstream springs with much higher values ofapproximately d18Ometeoric water (VSMOW) 5 22.0& in sur-face water samples collected in 2007 (Magiligan et al.,2008); within the Rio Muerto site complex, it is possiblethat individuals buried in cemetery M70 used morewater from the nearby springs, while individuals buriedin cemetery M43 used more water from the river, whichis located closer to M43. In addition to variability in oxy-gen isotope values in drinking water sources, storage,and treatment of water can affect oxygen isotope valuesin imbibed liquids (Daux et al., 2008; Knudson, 2009;Brettell et al., 2012). For example, experimental datahas shown that brewing may increase d18Ometeoric water

(VSMOW) values by 1.3&, while slow cooking liquidsincreases d18Ometeoric water (VSMOW) values by as much as

10.2& after 3 h (Brettell et al., 2012). In the MoqueguaValley, there is ample evidence for the consumption ofchicha, beer made from maize (Zea mays), at Tiwanaku-affiliated sites (Goldstein, 1993, 2003, 2005; Williams,2001; Moseley et al., 2005). Based on experimental dataon brewing (Brettell et al., 2012), individuals whoimbibed large amounts of 18O-enriched chicha couldexhibit higher d18Odrinking water (VSMOW) values in enamelor bone. However, while paleodiet and gendered foodchoices at the Rio Muerto site complex are currentlybeing investigated, data from other Tiwanaku-affiliatedsites in the Moquegua Valley has demonstrated thatmales consumed greater amounts of C4 plants such asmaize (Zea mays), likely in the form of chicha (Sand-ness, 1992).

Strontium and oxygen sources at Rio Muerto

At Rio Muerto, we argue that the strontium and oxy-gen sources in the diet were largely local, rather thanfrom non-local imports. The most likely sources for high-calcium, and high-strontium, foods were terrestrial plantsources; there is relatively little biogeochemical orarchaeological evidence for the consumption of marineproducts at Tiwanaku-affiliated sites in the MoqueguaValley (Sandness, 1992; Tomczak, 2003; Goldstein, 2005).There is little evidence for marine radiogenic strontiumisotope values, which would be similar to seawater[87Sr/86Sr 5 0.7092 (Veizer, 1989)], in the radiogenicstrontium isotope values in humans buried at the RioMuerto site complex. While strontium in water sourceswould likely contribute less bioavailable strontium thandietary strontium, radiogenic strontium isotope valuesin local water sources likely reflect local bedrock as wellas higher-altitude sources, and are reflected in the base-line faunal samples. There is also little evidence for seasalt production on the Peruvian coast (see discussion inFenner and Wright, 2014), and it is more likely that saltconsumed was obtained from terrestrial sources. Oxygenisotope sources likely derive from the Osmore River,which carries precipitation from higher altitudes, as wellas natural springs (see discussions in Magiligan andGoldstein, 2001; Williams, 2001, 2002; Magiligan et al.,2008; Stanish et al., 2010). Given the evidence thatstrontium and oxygen sources in the Moquegua Valleywere largely local, we argue that radiogenic strontiumisotope and oxygen isotope analysis can be used to inves-tigate paleomobility in specific individuals as well as themortuary population as a whole at the Rio Muerto sitecomplex.

MATERIALS

Dating to approximately AD 700–1050 (Goldstein,2005), the Rio Muerto site complex (sites M43, M48,M52, and M70) is located in the middle Moquegua Valleyof Peru and was excavated in 2006–2008 under the aus-pices of the Rio Muerto Archaeological Project, directedby Dr. Paul S. Goldstein and Lic. Patricia Palacios Fili-nich. At the M43 and M70 cemeteries, 171 whole or par-tial individuals in 158 tombs were excavated;preservation in the arid Moquegua Valley is exceptionaland mortuary, bioarchaeological, and paleodietary analy-ses are ongoing (Fig. 2; e.g., Baitzel, 2008; Plunger,2009; Baitzel and Goldstein, 2011; Becker, 2013). Ageand sex estimations were provided by Sarah Baitzel andSara Becker, who used standard osteological methods(Buikstra and Ubelaker, 1994; Buzon et al., 2005). Using



a sampling strategy designed to reflect the age and sexcomposition of the cemeteries, 57 samples from 33 indi-viduals were collected for radiogenic strontium isotoperesearch (Table 1). When possible, samples were col-lected from multiple dental and skeletal elements ineach individual to examine dietary and mobility patternsthroughout an individual’s lifetime; we present bothenamel and bone radiogenic strontium isotope data for24 individuals (Table 1). Radiogenic strontium isotopesamples were prioritized when there was not enoughenamel or bone for both radiogenic strontium and oxy-gen isotope analysis (Table 1). A subset of 47 enameland bone samples from 32 individuals was also analyzedfor their oxygen isotope compositions; we present bothenamel and bone oxygen isotope data for 15 individuals(Table 2). In light of the growing body of evidence thatboth sample pretreatment and instrumentation canaffect oxygen isotope data (Pestle et al., 2013; Pestleet al., in review), we used two different laboratories forsample preparation and analysis of oxygen isotope datafrom bone carbonate samples to explore the variabilityin oxygen isotope data from different laboratories(Tables 2 and 3). We note that only one laboratory wasused for radiogenic strontium isotope analysis, since thefirst author has successfully compared and used radio-genic strontium isotope data prepared at different labo-ratories using different mass spectrometers (Knudsonet al., 2012b; Knudson and Price, 2007; Knudson andTorres-Rouff, 2014).

METHODS

Radiogenic strontium isotope analyses

Radiogenic strontium isotope sample preparation andanalysis were performed under the direction of Drs.Kelly J. Knudson and Gwyneth Gordon at Arizona StateUniversity (ASU). Eight milligrams of tooth enamel pow-der or chemically cleaned and ashed bone was dissolvedin 0.50 mL of 5 M nitric acid (HNO3). The strontium wasseparated from the sample matrix using EiChromSrSpec resin, a crown-ether strontium-selective resin

(100–150 mm diameter). The enamel and bone sampleswere analyzed using the Neptune multicollector induc-tively coupled plasma mass spectrometer (MC-ICP-MS)in the ASU W.M. Keck Foundation Laboratory for Envi-ronmental Biogeochemistry. Recent 87Sr/86Sr analyses ofstrontium carbonate standard SRM-987 yielded a valueof 87Sr/86Sr 5 0.710261 6 0.000020 (2r), which is inagreement with analyses of SRM-987 using a thermalionization mass spectrometer, where87Sr/86Sr 5 0.710263 6 0.000016 (2r; Stein et al., 1997),and analyses of SRM-987 using an identical MC-ICP-MS, where 87Sr/86Sr 5 0.710251 6 0.000006 (2r; Balcaenet al., 2005).

Oxygen isotope analyses

To investigate the role of variability between laborato-ries in oxygen isotope analysis data (Pestle et al., 2013;Pestle et al., in review), samples were prepared at theASU Archaeological Chemistry Laboratory (ACL) underthe direction of Dr. Kelly J. Knudson and at the Univer-sity of California at San Diego (UCSD) Paleodiet Labora-tory under the direction of Dr. Margaret Schoeninger. Inboth locations, sample preparation for oxygen isotopeanalysis of archaeological hydroxyapatite carbonate(d18Ocarbonate) followed established methods in whichtooth enamel or bone powder was treated with 2%bleach (NaOCl) and then 0.1 M acetic acid (CH3COOH;Koch et al., 1997). More specifically, samples werecrushed to powder using an agate mortar and pestlethen treated with 0.04 mL of 2% bleach (NaOCl) pereach milligram of tooth enamel or bone. Samples weremixed with 2% bleach (NaOCl) on a mini-vortexer in2.0 mL centrifuge tubes for 60 s, and then left to sit atroom temperature for 24 h. Samples were rinsed threetimes with 0.50 mL of ultrapure Millipore water (H2O)at ASU and 1.0 mL of double-distilled deionized water(H2O) at UCSD, using a mini-vortexer for 60 s aftereach addition of water at both laboratories. Then, sam-ples were treated with 0.04 mL of 0.1 M acetic acid(CH3COOH) per each milligram of tooth enamel or bone.

Fig. 2. Rio Muerto site complex M70B tomb 11 (individual M70–2276) and associated organic offerings, including a decoratedbasket (M70 5 2264), pigment box (M70 5 2269), wooden kero drinking vessel (M70 5 2261), wooden spoon (M70 5 2262), comb(M70 5 2275), decorated gourd dipper (M70 5 2263), and embroidered chuspa (coca bag; M70 5 2294d) (Photographs by Paul S.Goldstein). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]




Samples were mixed with 0.1 M acetic acid (CH3COOH)on a mini-vortexer in 2.0 mL centrifuge tubes for 60 s,and then left to sit at room temperature for 24 h. Sam-

ples were rinsed three times with 0.50 mL of ultrapureMillipore water (H2O) and 1.0 mL of double-distilleddeionized water (H2O) at UCSD, using a mini-vortexer

TABLE 1. Bioarchaeological and biogeochemical data from archaeological human enamel and bone samples from individualsburied at the site of Rio Muerto, Peru

ASU laboratorynumber

Specimen (feature)number

Site, sector,tomb Agea Sexa Materialsb Ca/P U/Ca 87Sr/86Sr

ACL-3308 M43-3018 M43B-5 5–9 IND R rib 4 2.0 3.9E-05 0.70682ACL-3295 M43-3054 M43B-3 35–40 M LLPM1 2.1 2.6E-05 0.70672ACL-3309 M43-3054 M43B-3 35–40 M R rib 2 2.2 1.4E-05 0.70696ACL-3296 M43-3185 M43B-6 A M ULM1 2.1 6.8E-05 0.71090ACL-3310 M43-3185 M43B-6 A M R rib 2 2.2 1.1E-03 0.70705ACL-3311 M43-3233 M43B-14 2–4 IND L rib 4 2.1 1.2E-05 0.70701ACL-3312 M43-3402 M43B-27 2–4 IND L rib 5 2.0 1.7E-05 0.70657ACL-3313 M43-3414 M43A-30 50–59 M L rib 2 2.1 7.9E-06 0.70753ACL-3297 M43-3414 M43A-30 50–59 M LLC 2.1 3.4E-05 0.70793ACL-3298 M43-3435 M43B-4 JUV IND LLM1 2.1 2.1E-05 0.70791ACL-3314 M43-3435 M43B-4 JUV IND R rib 3 2.0 9.6E-06 0.70753ACL-3299 M43-4141 M43A-37 35–39 M LLM2 2.1 2.3E-05 0.70778ACL-3315 M43-4141 M43A-37 35–39 M L rib 2 2.1 1.4E-05 0.70748ACL-3300 M43-4237 M43B-40 25–31 F ULM2 2.1 1.0E-05 0.72018ACL-3316 M43-4237 M43B-40 25–31 F R rib 2 2.2 3.5E-06 0.71323ACL-3301 M43-4345 M43A-46 25–50 PM LLM1 2.0 2.9E-05 0.70705ACL-3317 M43-4345 M43A-46 25–50 PM R proximal

foot phalanx2.1 8.8E-06 0.70775

ACL-3302 M43-4835 M43A-70 33–46 PF LLM1 2.0 2.5E-05 0.70814ACL-3318 M43-4835 M43A-70 33–46 PF L rib 2 2.1 1.3E-05 0.70706ACL-3303 M43-4870 M43A-73 13–15 PF LRM2 2.1 1.7E-05 0.70686ACL-3319 M43-4870 M43A-73 13–15 PF R rib 2 2.1 1.3E-05 0.70689ACL-3304 M43-4878 M43A-75 25–28 M LLM2 2.0 2.6E-05 0.70778ACL-3320 M43-4878 M43A-75 25–28 M R rib 2 2.2 2.5E-05 0.70715ACL-1583 M70-2370 M70B-18 21–23 M R rib 4 1.9 4.4E-09 0.70821ACL-1584 M70-2495 M70B-10 19–22 M L rib 4 2.0 1.0E-08 0.70701ACL-1585 M70-2495 M70B-10 19–22 M LRC 2.3 3.4E-11 0.70712ACL-1586 M70-2621 M70B-37 12–15 IND L rib 6 2.0 NA 0.70768ACL-1587 M70-2621 M70B-37 12–15 IND LLPM2 2.3 3.6E-11 0.70681ACL-1588 M70-2642 M70B-34 34–42 M L rib 4 2.2 1.1E-06 0.70791ACL-1589 M70-2642 M70B-34 34–42 M LRPM1 1.9 NA 0.70902ACL-1590 M70-2787 M70B-57 43–58 F R rib 3 2.1 6.8E-09 0.70743ACL-1591 M70-2787 M70B-57 43–58 F URM2 1.9 NA NAACL-1592 M70-2877 M70B-61 22–23 M L rib 5 2.1 2.6E-06 0.70781ACL-1593 M70-2877 M70B-61 22–23 M ULI1 2.3 4.4E-11 0.70803ACL-1594 M70-2896 M70B-54 30–35 M L rib 3 2.1 1.2E-09 0.70821ACL-1595 M70-2896 M70B-54 30–35 M LRPM2 2.0 NA 0.70822ACL-1596 M70-2956 M70B-66 25–27 F L rib 5 2.2 2.0E-06 0.70777ACL-1597 M70-2956 M70B-66 25–27 F ULI1 2.3 3.6E-11 0.70793ACL-1598 M70-2985 M70B-69 27–30 F R rib 3 2.1 NA 0.70765ACL-1599 M70-2985 M70B-69 27–30 F URI2 2.3 6.2E-11 0.70785ACL-3305 M70-4429 M70B-95 25–30 M LRM1 2.0 1.2E-05 0.70811ACL-3321 M70-4429 M70B-95 25–30 M R rib 2 2.1 1.0E-05 0.70739ACL-3306 M70-4443 M70B-94 34–40 M LLM2 2.1 4.1E-05 0.70792ACL-3322 M70-4443 M70B-94 34–40 M L rib 2 2.2 6.2E-04 0.70731ACL-3307 M70-4468 M70B-75 34–39 F LLC 2.0 1.5E-05 0.71297ACL-3323 M70-4468 M70B-75 34–39 F L rib 2 2.2 3.0E-04 0.70775ACL-1623 M70-2236 M70B-19 18–20 F L rib 6 2.1 4.0E-07 0.70772ACL-1624 M70-2236 M70B-19 18–20 F ULM2 2.0 1.2E-07 0.70774ACL-1625 M70-2248 M70B-7 4–8 IND L rib 6 2.2 3.3E-07 0.70772ACL-1626 M70-2276 M70B-11 25–31 F L rib 5 2.1 1.3E-08 0.70732ACL-1627 M70-2380 M70B-22 2–4 IND L rib 6 2.0 1.3E-07 0.70709ACL-1628 M70-2456 M70B-30 4–6 IND L rib 6 2.1 8.0E-07 0.70758ACL-1629 M70-2478 M70B-29 7–11 IND L rib 6 2.1 1.2E-08 0.70769ACL-1630 M70-2478 M70B-29 7–11 IND URM1 2.3 4.7E-11 0.70704ACL-1631 M70-2840 M70B-53 45–55 M R rib 2 2.0 2.4E-08 0.70838ACL-1633 M70-2999 M70B-65 34–39 F L rib 5 2.1 8.2E-08 0.70742ACL-1634 M70-2999 M70B-65 34–39 F URI1 2.3 2.0E-10 0.70806

a Age is presented in years and abbreviations used are as follows: M (male), PM (probable male), F (female), PF (probable female),IND (indeterminate), and JUV (juvenile).b Abbreviations: U: upper; L: lower; R: right; L: left; M: molar; C: canine; PM: premolar. Enamel samples are labeled according totooth position; for example, LLM1 corresponds to a lower left first molar.



for 60 s after each addition of water, and then dried at50�C for 24 h.

Archaeological hydroxyapatite carbonate (d18Ocarbon-

ate) samples that were prepared at ASU were thenanalyzed at the Colorado Plateau Stable Isotope Labo-ratory at Northern Arizona University (NAU). AtNAU, samples were analyzed using a Delta V Advant-age isotope ratio mass spectrometer equipped with aGas Bench II. International standards NBS-18 andNBS-19 were used to create the calibration curve.External and internal laboratory standards [NBS-18,NBS-19, Joplin calcite (CC), and an internal laboratory

calcium carbonate (CaCO3) standard] were reproduci-ble within 60.2& for d18Ocarbonate(VPDB) values. Accu-racy was within 60.2& for d18Ocarbonate(VPDB) values inall external and internal standards analyzed at NAU.More specifically, at NAU, analyses of workingstandard Joplin calcite (CC) yielded a value of meand18Ocarbonate(VPDB) 5 223.41 6 0.19& (n 5 19, 1r); long-term reproducibility of Joplin CC at NAU is �60.16&for d18O. In addition, meand18Ocarbonate(VPDB) 5 213.01 6 0.14& (n 519, 1r) for aninternal laboratory calcium carbonate (CaCO3) stand-ard at NAU.

TABLE 2. Oxygen isotope data from archaeological human enamel and bone samples from individuals buried at the site of RioMuerto, Peru

ASU specimennumber

ASU ACLnumber

UCSD ASnumber Materiala

ASUb

d18Ocarbonate(VSMOW)

UCSDd18Ocarbonate(VSMOW)

M43–3018 ACL-3308 AS-0052 R rib 4 23.0 26.7M43-3054 ACL-3295 NA LLPM1 22.1 NAM43-3054 ACL-3309 AS-0053 R rib 2 22.2 24.2M43-3185 ACL-3296 NA ULM1 21.9 NAM43-3185 ACL-3310 AS-0054 R rib 2 20.7 24.1M43-3233 ACL-3311 AS-0055 L rib 4 24.7 26.4M43-3402 ACL-3312 NA L rib 5 25.7 NAM43-3414 ACL-3313 AS-0057 L rib 2 21.2 22.8M43-3414 ACL-3297 NA LLC 20.0 NAM43-3435 ACL-3298 NA LLM1 20.2 NAM43-3435 ACL-3314 AS-0058 R rib 3 26.4 27.0M43-4141 ACL-3299 NA LLM2 19.8 NAM43-4141 ACL-3315 AS-0059 L rib 2 21.7 24.7M43-4237 ACL-3300 NA ULM2 23.0 NAM43-4237 ACL-3316 AS-0060 R rib 2 22.1 25.7M43-4345 ACL-3301 NA LLM1 21.1 NAM43-4345 ACL-3317 AS-0061 R proximal foot

phalanx22.2 23.2

M43-4835 ACL-3302 NA LLM1 20.5 NAM43-4835 ACL-3318 AS-0062 L rib 2 22.5 24.6M43-4870 ACL-3303 NA LRM2 22.4 NAM43-4870 ACL-3319 AS-0063 R rib 2 23.0 22.8M43-4878 ACL-3304 NA LLM2 20.4 NAM43-4878 ACL-3320 AS-0064 R rib 2 21.4 22.6M70–2236 ACL-1623 AS-0033 L rib 6 NA 20.6M70-2248 ACL-1625 AS-0034 L rib 6 NA 23.9M70-2276 ACL-1626 AS-0035 L rib 5 NA 20.9M70-2370 ACL-1583 AS-0024 R rib 4 NA 24.3M70-2380 ACL-1627 AS-0036 L rib 6 NA 27.1M70-2456 ACL-1628 AS-0037 L rib 6 NA 26.5M70-2478 ACL-1629 AS-0038 L rib 6 NA 22.3M70-2495 ACL-1584 AS-0025 L rib 4 NA 24.6M70-2621 ACL-1586 AS-0026 L rib 6 NA 21.3M70-2642 ACL-1588 AS-0027 L rib 4 NA 24.5M70-2787 ACL-1590 AS-0028 R rib 3 NA 20.9M70-2787 ACL-1591 NA URM2 21.2 NAM70-2840 ACL-1631 AS-0039 R rib 2 NA 21.2M70-2877 ACL-1592 AS-0029 L rib 5 NA 23.6M70-2896 ACL-1594 AS-0030 L rib 3 NA 20.4M70-2956 ACL-1596 AS-0031 L rib 5 22.1 23.7M70-2985 ACL-1598 AS-0032 R rib 3 NA 23.1M70-2999 ACL-1633 AS-0040 L rib 5 NA 24.9M70-4429 ACL-3305 NA LRM1 20.9 NAM70-4429 ACL-3321 AS-0065 R rib 2 20.6 24.0M70-4443 ACL-3306 NA LLM2 18.1 NAM70-4443 ACL-3322 AS-0066 L rib 2 21.2 22.8M70-4468 ACL-3307 NA LLC 22.7 NAM70-4468 ACL-3323 AS-0067 L rib 2 19.6 23.8

a Abbreviations: U: upper; L: lower; R: right; L: left; M: molar; C: canine; PM: premolar. Enamel samples are labeled according totooth position; for example, LLM1 corresponds to a lower left first molar.b The standard deviations for d18Ocarbonate(VSMOW) data are 60.2%.



All archaeological hydroxyapatite carbonate (d18Ocar-

bonate) samples prepared at UCSD were analyzed at theUCSD Analytical Facility managed by Dr. Bruce Deck.Samples were analyzed using a Thermo-Finnigan DeltaXP Plus mass spectrometer equipped with a Gas BenchThermo MAT 253. International standards NBS-18 andNBS-19 were used to create the calibration curve. Exter-nal and internal laboratory standards (NBS-18, NBS-19,and two internal laboratory (CaCO3) standards) werereproducible within 60.2& for d18Ocarbonate(VPDB) values.Accuracy was within 60.3& for d18Ocarbonate(VPDB) valuesin all external and internal standards analyzed at

UCSD. More specifically, at UCSD, 10 months of analy-ses of a working CaCO3 standard yielded a value ofd18Ocarbonate(VPDB) 5 217.99 6 0.31& (n 5 55, 1r).

For all data generated, oxygen isotope ratios (d18Ocar-

bonate) are expressed in per mil (&) using the followingstandard formula: d18O 5 [(18O/16Osample)/(

18O/16Ostandard)– 1] 3 1,000 (Craig, 1961b; Coplen, 1994; Werner andBrand, 2001). To convert our d18Ocarbonate(VPDB) tod18Ocarbonate(VSMOW) data, we used the conversion equa-tion d18OVSMOW 5 [1.03091 3 (d18OVPDB)] 1 30.91 (Coplenet al., 1983). We then converted our d18Ocarbonate(VSMOW)

values to d18Ophosphate(VSMOW) values using the

TABLE 3. Biogeochemical data from Rio Muerto individuals with multiple archaeological human enamel and bone samples

Specimen(feature)number Age Sex

ASU laboratorynumber Materiala 87Sr/86Sr

ASUb

d18O carbonate(VSMOW)

UCSDd18O carbonate(VSMOW)

M43-3054 35–40 M ACL-3295 LLPM1 0.70672 22.1 NAM43-3054 35–40 M ACL-3309 R rib 2 0.70696 22.2 24.2M43-3185 A M ACL-3296 ULM1 0.71090 21.9 NAM43-3185 A M ACL-3310 R rib 2 0.70705 20.7 24.1M43-3414 50–59 M ACL-3313 L rib 2 0.70753 21.2 22.8M43-3414 50–59 M ACL-3297 LLC 0.70793 NA NAM43-3435 JUV IND ACL-3298 LLM1 0.70791 20.2 NAM43-3435 JUV IND ACL-3314 R rib 3 0.70753 26.4 27.0M43-4141 35–39 M ACL-3299 LLM2 0.70778 19.8 NAM43-4141 35–39 M ACL-3315 L rib 2 0.70748 21.7 24.7M43-4237 25–31 F ACL-3300 ULM2 0.72018 23.0 NAM43-4237 25–31 F ACL-3316 R rib 2 0.71323 22.1 25.7M43-4345 25–50 PM ACL-3301 LLM1 0.70705 21.1 NAM43-4345 25–50 PM ACL-3317 R proximal foot

phalanx0.70775 22.2 23.2

M43-4835 33–46 PF ACL-3302 LLM1 0.70814 20.5 NAM43-4835 33–46 PF ACL-3318 L rib 2 0.70706 22.5 24.6M43-4870 13–15 PF ACL-3303 LRM2 0.70686 22.4 NAM43-4870 13–15 PF ACL-3319 R rib 2 0.70689 23.0 22.8M43-4878 25–28 M ACL-3304 LLM2 0.70778 20.4 NAM43-4878 25–28 M ACL-3320 R rib 2 0.70715 21.4 22.6M70-2495 19–22 M ACL-1584 L rib 4 0.70701 NA 24.6M70-2495 19–22 M ACL-1585 LRC 0.70712 NA 21.3M70-2621 12–15 IND ACL-1586 L rib 6 0.70768 NA NAM70-2621 12–15 IND ACL-1587 LLPM2 0.70681 NA NAM70-2642 34–42 M ACL-1588 L rib 4 0.70791 NA 24.5M70-2642 34–42 M ACL-1589 LRPM1 0.70902 NA NAM70-2787 43–58 F ACL-1590 R rib 3 0.70743 NA 20.9M70-2787 43–58 F ACL-1591 URM2 NA 21.2 NAM70-2877 22–23 M ACL-1592 L rib 5 0.70781 NA 23.6M70-2877 22–23 M ACL-1593 ULI1 0.70803 NA NAM70-2896 30–35 M ACL-1594 L rib 3 0.70821 NA 20.4M70-2896 30–35 M ACL-1595 LRPM2 0.70822 NA NAM70-2956 25–27 F ACL-1596 L rib 5 0.70777 22.1 23.7M70-2956 25–27 F ACL-1597 ULI1 0.70793 NA NAM70-2985 27–30 F ACL-1598 R rib 3 0.70765 NA 23.1M70-2985 27–30 F ACL-1599 URI2 0.70785 NA NAM70-4429 25–30 M ACL-3305 LRM1 0.70811 20.9 NAM70-4429 25–30 M ACL-3321 R rib 2 0.70739 20.6 24.0M70-4443 34–40 M ACL-3306 LLM2 0.70792 18.1 NAM70-4443 34–40 M ACL-3322 L rib 2 0.70731 21.2 22.8M70-4468 34–39 F ACL-3307 LLC 0.71297 22.7 NAM70-4468 34–39 F ACL-3323 L rib 2 0.70775 19.6 23.8M70-2236 18–20 F ACL-1623 L rib 6 0.70772 NA NAM70-2236 18–20 F ACL-1624 ULM2 0.70774 NA NAM70-2478 7–11 IND ACL-1629 L rib 6 0.70769 NA NAM70-2478 7–11 IND ACL-1630 URM1 0.70704 NA NAM70-2999 34–39 F ACL-1633 L rib 5 0.70742 NA 24.9M70-2999 34–39 F ACL-1634 URI1 0.70806 NA NA

a Abbreviations: U: upper; L: lower; R: right; L: left; M: molar; C: canine; PM: premolar. Enamel samples are labeled according totooth position; for example, LLM1 corresponds to a lower left first molar.b The standard deviations for d18Ocarbonate(VSMOW) data are 60.2%.



conversion equation d18Ocarbonate(VSMOW) 5 (8.5 1(d18Ophosphate))/0.98 (Iacumin et al., 1996). Finally, weconverted our d18Ophosphate(VSMOW) values to d18Odrinking

water(VSMOW) values using the conversion equationd18Odrinking water(VSMOW) 5 (1.54 3 (d18Ophosphate (VSMOW))– 33.72 (Daux et al., 2008). However, we note that thereare different formulae that have been used to convertoxygen isotope values in hydroxyapatite into oxygen iso-tope values in drinking water (Longinelli, 1984; Luzet al., 1984; Levinson et al., 1987; Daux et al., 2008; Pol-lard et al., 2011), and that directly comparing d18Ocarbon-

ate values is preferable and removes error introduced bythe conversion equations (Pollard et al., 2011).

Major, minor, and trace elemental concentrationanalyses

Elemental concentration sample preparation andanalysis were performed under the direction of Drs.Kelly J. Knudson and Gwyneth Gordon at ASU toassess the degree of diagenetic contamination. Enamelpowder or chemically cleaned bone ash samples weredissolved in 0.64 mL of 5 M nitric acid (HNO3), anddiluted with 9.36 mL of Millipore water (H2O). Thesedata were generated using a Thermo-Finnigan quad-rupole inductively coupled plasma mass spectrometer(Q-ICP-MS) in the ASU W.M. Keck Foundation Labo-ratory for Environmental Biogeochemistry, wheremean Ca/P 5 2.18 6 0.01 (2r, n 5 5) for ACL standardCUE-0001.

FTIR-ATR analyses

To further assess the degree of diagenetic contamina-tion, a subset of archaeological bone (�40%) samples wasanalyzed by Andrew Somerville using Fourier-TransformInfrared spectroscopy with the Attenuated Total Reflec-tion technique (FTIR-ATR) at the UCSD Department ofChemistry and Biochemistry. To obtain the infrared split-ting factor (IR-SF) and carbonate to phosphate (C/P)ratios, both of which reflect the degree of post-burial alter-ation to bone bioapatite (Shemesh, 1990; Wright andSchwarcz, 1996; Smith et al., 2007), �5 mg of powderedbone were pressed at 10,000 psi on a Smart-iTR diamondcrystal ATR stage equipped to a Thermo Scientific Nicolet6700 FT-IR spectrometer, bypassing the KBr pelletingtechnique (see Thompson et al., 2009; Hollund et al.,2013; Beasley et al., 2014). Spectra were collected in 100scans and controlled for background variance. To obtainIR-SF values, absorbance values were summed at wave-numbers 565 (v4 PO4) and 605 cm21 (v4 PO4), and dividedby the value at �590 cm211 (Weiner and Bar-Yosef, 1990).To calculate C/P, absorbance values at 1415 cm21 (v3 CO3)were divided by those at 1035 (v3 PO4; Wright andSchwarcz, 1996).

RESULTS

The Rio Muerto archaeological human enamel andbone values range from 87Sr/86Sr 5 0.7065720.72018(Table 1), with a mean of 87Sr/86Sr 5 0.70804 6 0.00207

Fig. 3. Radiogenic strontium isotope ratios from archaeological human tooth enamel and bone samples from Rio Muerto, Peru.



(1r, n 5 55). Oxygen isotope data ranges fromd18Ocarbonate(VSMOW) 5 118.1 to 127.0& (Table 2). MeanCa/P 5 2.1 6 0.1 (1r, n 5 57) and mean U/Ca 5 4.9 310205 6 1.8 3 10204 (1r, n 5 52). Using FTIR-ATR, meanIR-SF5 2.88 6 0.11 (1r, n 5 33) of Rio Muerto bone sam-ples analyzed and mean C/P 5 0.30 6 0.04 (1r, n 5 33).

DISCUSSION

Diagenetic contamination at Rio Muerto

Major, minor, and trace element concentration dataand FTIR-ATR spectroscopy were used to better under-stand diagenetic or post-depositional contamination inarchaeological human samples from the Moquegua Val-ley. In human bone, biogenic Ca/P 5 2.1. Some samplesexhibited slightly higher or lower Ca/P values, whichmay indicate at least some diagenetic contamination inthese samples (Table 2). However, mean Ca/P and U/Cavalues are generally low [Ca/P 5 2.1 6 0.1 (1r, n 5 57)and mean U/Ca 5 4.9 3 10205 6 1.8 3 10204 (1r,n 5 52)], which indicates largely biogenic major, minor,and trace element concentrations in these samples.Moreover, FTIR-ATR analysis yielded a “splitting factor”(IR-SF) mean of 2.88 6 0.11 (1r, n 5 33) and a carbonateto phosphate ratio (C/P) mean of 0.30 6 0.04 (1r, n 5 33).Unaltered hydroxyapatite should exhibit an IR-SF (ATR)range of 2.5–3.5 and an acceptable C/P range of 0.15–0.45, based on published data (Wright and Schwarcz,1996; Smith et al., 2007; Thompson et al., 2009; Hollundet al., 2013) and results from internal laboratory analy-ses of modern faunal bone using the same instrument as

that of this study. Therefore, since all Rio Muertoarchaeological bone samples analyzed fall within theseIR-SF and C/P ranges, our FTIR-ATR data suggest thatthe Moquegua Valley bone specimens underwent no sig-nificant postburial alteration.

Paleomobility at Rio Muerto: radiogenicstrontium isotope data

As previously stated, for all enamel and bone samplesanalyzed, mean 87Sr/86Sr 5 0.70804 6 0.00207 (1r,n 5 55). Bioavailable radiogenic strontium isotope valuesin local modern small mammal samples from Moquegua,Peru exhibited mean 87Sr/86Sr 5 0.70625 6 0.00018 (1r,n 5 3; Knudson et al., 2004). Based on the mean faunal87Sr/86Sr value plus or minus two standard deviations(Price et al., 2002; Bentley et al., 2004; Evans andTatham, 2004), one “local” range for the Moquegua Val-ley is 87Sr/86Sr 5 0.705920.7066. When the five clearly“nonlocal” 87Sr/86Sr values above 87Sr/86Sr 5 0.709 areexcluded, mean 87Sr/86Sr 5 0.70751 6 0.00045 (1r,n 5 50). The mean 87Sr/86Sr value in “local” archaeologi-cal human remains from Rio Muerto is slightly higherthan the mean 87Sr/86Sr value from modern small mam-mal samples (Knudson et al., 2004), yet both human andfaunal mean values are within radiogenic strontium iso-tope values observed in the late Cenozoic volcanic rocksof southern Peru and northern Chile (James, 1982).Rather than argue that all individuals with 87Sr/86Srvalues slightly outside of the “local” range spent a por-tion of their lives outside of the region, which wouldlead to a very high number of “non-local” individuals in

Fig. 4. Oxygen isotope data from archaeological human tooth enamel and bone samples from Rio Muerto, Peru. The gray barsshow the MMD value of 3.1% and link samples that were collected from the same skeletal element from the same individuals andanalyzed at different laboratories. The gray bars also illustrate the oxygen isotope data from five individuals for whom the differ-ence in d18Ocarbonate(VSMOW) values generated in two laboratories exceeds the MMD value of 3.1% (M43-3018, M43-3185, M43-4237,M70-4429, and M70-4468).



this study, we argue that the strontium sources in mostindividuals’ diet came from a wider, yet still local, rangeof terrestrial dietary resources within the middle Moque-gua Valley (Fig. 3).

Paleomobility at Rio Muerto: oxygen isotope data

Interlaboratory variability in oxygen isotopedata. To better understand geographic origins in theRio Muerto mortuary population, a subset of 47 enameland bone samples from 32 individuals was also analyzedusing oxygen isotopes (Tables 2 and 3). Sixteen archaeo-logical bone samples were prepared and analyzed in twodifferent laboratories using the same methods to investi-gate inter-laboratory variability in oxygen isotope analy-sis (Fig. 4). The oxygen isotope values generated at ASUand UCSD ranged from d18Ocarbonate(VSMOW) 5 0.2 to4.1& in the same bone samples, with a mean differenceof d18Ocarbonate(VSMOW) 5 22.1 6 1.2& (1r, n 5 16).Unfortunately, these data are perhaps not surprising,given recent data on intralaboratory and interlaboratoryvariability (Pestle et al., 2013, in review). Recent repli-cate analyses were performed on bone hydroxyapatitesamples from the same skeletal element in the samearchaeological individual but analyzed in 21 differentlaboratories, including the laboratories directed by Drs.Knudson and Schoeninger (Pestle et al., in review).These data have effectively demonstrated that differen-ces in sample pretreatment, instrumentation, and datacalibration result in a range of 6.7& in d18Ocarbona-

te(VPDB) values in the same archaeological bone sample(Pestle et al., in review). Rather than attempt to“correct” or discard data from one laboratory included inthis study, we present all of our oxygen isotope data asgenerated from both laboratories. However, we followrecent recommendations and use a Meaningful Mini-mum Difference (MMD) value of 3.1& in d18Ocarbona-

te(VPDB) values in this dataset (Pestle et al., in review).In other words, we only interpret differences in oxygenisotope values as meaningful for inferences of mobility ifthe differences are >3.1& in d18Ocarbonate(VPDB) ord18Ocarbonate(VSMOW) values. Finally, while we report alld18Ocarbonate(VPDB) values generated (Tables 2 and 3), wedo not include oxygen isotope data from the five individ-uals for whom the difference in bone d18Ocarbonate(VSMOW)

values generated in two laboratories exceeds the MMDvalue of 3.1& (M43-3018, M43-3185, M43-4237, M70-4429, and M70-4468) in our anthropological interpreta-tions of paleomobility.

Tissue-dependent variability in oxygen isotopedata. When examining the entire oxygen isotope da-taset, the oxygen isotope data range fromd18Ocarbonate(VSMOW) 5 18.1& to d18Ocarbonate(VSMOW)527.0& (Table 2). The variability in oxygen isotope valuesmay come from a variety of sources, only some of whichrepresent movement from different environmental zones(Knudson, 2009). In addition to the interlaboratory vari-ability, as discussed above, some variability in d18Ocarbo-

nate(VSMOW) values may result from food and waterprocessing involving boiling or fermentation, whichcause the preferential evaporation of 16O and enrich-ment of 18O, altering the isotopic value of the final prod-uct consumed (Brettell et al., 2012; Munro et al., 2007;Wilson et al., 2007). In addition, we expect that oxygenisotope data obtained from enamel and/or bone that

formed before or during the weaning process will reflectthe 18O-enrichment in breast milk (Roberts et al., 1988).To minimize the effects of 18O-enrichment in breastmilk, one can focus on bone samples from individualswho died as adults. Based on the previously discussedconversion equations (see discussion in Pollard et al.,2011), for all bone samples analyzed at ASU, meand18Odrinking water(VSMOW) 5 213.7 6 3.5& (1r, n 5 21), andbone samples analyzed at UCSD exhibit mean d18Odrink-

ing water(VSMOW) 5 211.90 6 2.9& (1r, n 5 32). Based onthese data, we infer that individuals who died as adultsand were buried at Rio Muerto imbibed water from sour-ces that exhibited a variety of d18O values consistentwith observed d18Ometeoric water (VSMOW) values in Moque-gua Valley groundwater (Magiligan et al., 2008) andLake Titicaca Basin surface water (IAEA/WMO, 2006).

However, although the most conservative way to avoid18O-enrichment in breast milk is to only analyze bonesamples from individuals who died as adults, we notethat expected 18O-enrichment in enamel that formedduring breast milk consumption should be much lowerthan the MMD value of 3.1& in d18Ocarbonate(VPDB) (seediscussions in Wright and Schwarcz, 1998, 1999; Duprasand Tocheri, 2007; Toyne et al., 2014). For example, forall first molar samples analyzed at ASU, mean d18Odrink-

ing water(VSMOW) 5 215.2 6 0.9& (1r, n 5 5); permanentfirst molar crowns begin to form about 10 weeks beforebirth and continue to form until about three years of age(Hillson, 1996). For all second molar samples analyzedat ASU, mean d18Odrinking water(VSMOW) 5 215.4 6 2.7&(1r, n 5 6); second molar crowns form between approxi-mately 3 and 7 years (Hillson, 1996). Interestingly, thereis much more variability in the second molar and boned18Odrinking water(VSMOW) values than the first molard18Odrinking water(VSMOW) values, possibly reflecting agreat variety of oxygen isotope sources in imbibedliquids and increased mobility after the first three yearsof life.

While some of these individuals may have inhabiteddifferent environmental zones during their lives, thecomplexities of the movement of water in the dry Andesand the ways in which chicha, or maize beer, consump-tion may affect these values is not well understood(Knudson, 2009). However, together, radiogenic stron-tium and oxygen isotope values suggest that severalindividuals interred within the Rio Muerto site complexspent a portion of their lives in different geological andenvironmental zones.

Tiwanaku travelers: paleomobility data inarchaeological context

First-generation migrants buried in the Rio Muertosite complex. Here, we discuss specific individualswith “nonlocal” radiogenic strontium and/or oxygen iso-tope values, contextualized with detailed information onmortuary treatment. We argue that a person-centeredmigration history approach can effectively be used toreconstruct paleomobility at both the level of the popula-tion and the individual. We first focus on four individu-als who exhibit radiogenic strontium isotope valuesmuch higher than the “local” range for the MoqueguaValley (Fig. 3). The first of these is M43-4237, an adultfemale buried in tomb 40 in the M43B cemetery. Individ-ual M43-4237 was buried in a seated, flexed position,wrapped in a camelid wool tunic, or manta, bound withbraided vegetable fiber rope, and placed facing east in



an unlined pit in the M43B cemetery. All of these fea-tures are typical of Tiwanaku-style interments of adultsin the M43A and M43B cemeteries. However, individualM43-4237 is one of only two individuals in the entireexcavated Rio Muerto mortuary population (n 5 171)without intentional cranial modification. Cranial modifi-cation must be performed in the first years of life, and,in the Andes, is a permanent and highly visible markerof community identity imposed on an individual by thelarger community (Blom, 2005; Torres-Rouff, 2002,2009). An unmodified cranium would have distinguishedindividual M43-4237 from the majority of Rio Muertoinhabitants, who exhibited fronto-occipital cranial modi-fication. Finally, unlike the majority of burials in the RioMuerto cemeteries, individual M43-4237 was notinterred with a feathered headdress.

Individual M43-4237 exhibited the two highest radio-genic strontium isotope values at Rio Muerto(87Sr/86Sr 5 0.72018 ULM2, 87Sr/86Sr 5 0.71323 rib). Thehigh enamel 87Sr/86Sr value is consistent with bioavail-able strontium values from geologic zones in the easternBolivian highlands, including the Cochabamba Valley,where modern faunal samples exhibit mean87Sr/86Sr 5 0.72148 6 0.00162 (1r, n 5 4; Lucas, 2012),and Potosi, where modern faunal samples exhibitedhigher radiogenic strontium isotope values such as87Sr/86Sr50.713233 and 87Sr/86Sr50.720503 (Knudsonet al., 2005). The bone 87Sr/86Sr value from individualM43-4237 is lower, and may reflect residence in theMoquegua Valley shortly before death; in this case, thebone value of 87Sr/86Sr 5 0.71323 may reflect averagingbetween the Moquegua Valley and a geologic zone orzones with much higher 87Sr/86Sr values. When con-verted to drinking water values, individual M43-4237exhibits d18Odrinking water(VSMOW) 5 213.5& in enamel,which is consistent with d18Odrinking water(VSMOW) values

observed in the altiplano (Knudson, 2009). Using multi-ple lines of isotopic evidence, we interpret these data asindicating a recent first-generation immigrant, likelyfrom the eastern Bolivian highlands or Cochabamba Val-ley, which exhibit baseline isotopic values consistentwith human isotopic values presented here, who arrivedin the Moquegua Valley as an adult, possibly throughpatrilocal mate exchange, and died shortly afterwards atthe Rio Muerto site. After death, despite an unmodifiedcranium and “nonlocal” geographic origins, this individ-ual was buried in typical Rio Muerto burial, althoughwithout a feather headdress or asymmetrically stripedembroidered edge manta, believed a mark of seniorityamong adult females at Rio Muerto (Plunger, 2009;Plunger and Goldstein, 2013).

A second adult female, M70-4468, buried in M70Btomb 75, was also a likely a first-generation immi-grant, but may have resided in the Moquegua Valleyfor some time before death. This individual was bur-ied in a manta finished with polychrome embroidery,bound with braided vegetable fiber rope, and buriedseated, flexed, and facing east, with a wooden spin-dle. The enamel isotopic values exhibited by individ-ual M70-4468 (87Sr/86Sr 5 0.71297 LLC, d18Odrinking

water(VSMOW) 5 212.5&) are consistent with enamelformation in either parts of the Bolivian altiplano oraveraging between an area like the Cochabamba Val-ley and the Moquegua Valley. This individual, how-ever, has a relatively low bone radiogenic strontiumisotope value of (87Sr/86Sr 5 0.70775 L rib 2), suggest-ing the incorporation of bioavailable strontium fromthe Moquegua Valley before death. Although we can-not confirm whether individual M70-4468 arrived atRio Muerto as a juvenile or adult, it is possible thatshe too arrived as an adult of reproductive age, per-haps through patrilocal mate exchange.

There are two adult male individuals buried at RioMuerto who exhibit radiogenic strontium isotope valuesconsistent with residence in the Lake Titicaca Basin ofBolivia and Peru (Fig. 3). In the Lake Titicaca Basin,the “local” range based on modern faunal samples is87Sr/86Sr 5 0.708720.7105 (Knudson, 2008). IndividualM43-3185 was an adult male with fronto-occipital cra-nial modification who was buried facing east in M43Btomb 6, a completely stone-lined tomb. This individualwas buried in a polychrome warp stripe plainweavetunic, brown blanket and hat, bound with braided vege-table fiber rope, and buried with shells, greenstonebeads, two decorated baskets, a wooden spoon, aworked gourd and a black-on-red slipped ceramic kero(drinking vessel) with a Chen Chen/Tiwanaku V stylestep stair and volute motif (Fig. 5). Individual M43-3185 exhibited enamel isotope ratios consistent withresidence in the Lake Titicaca Basin during the firstyears of life (87Sr/86Sr 5 0.71090 ULM1, d18Odrinking

water(VSMOW) 5 213.8&). However, his bone radiogenicstrontium isotope ratio of (87Sr/86Sr 5 0.70705 ULM1) iswithin the local range for the Moquegua Valley. This isconsistent with a first-generation immigrant who livedin the Lake Titicaca Basin as a juvenile, and who hadbeen living in the Moquegua Valley for some time atthe time of death.

Individual M70-2642 was an adult male buried inM70B tomb 34. This individual displayed mild fronto-occipital cranial modification and was dressed in abrown warp face textile. Individual M70-2642 displayedenamel radiogenic strontium isotope values within the

Fig. 5. Black-on-red slipped ceramic kero (drinking vessel)with a Chen Chen/Tiwanaku V style step-stair and volute motifburied with individual M43-3185 in M43B tomb 6 (Photographby Paul S. Goldstein). [Color figure can be viewed in the onlineissue, which is available at wileyonlinelibrary.com.]




Lake Titicaca Basin local range (87Sr/86Sr 5 0.70902LRPM1). In contrast, his bone radiogenic strontium iso-tope value (87Sr/86Sr 5 0.70791 L rib 4) is within thelocal range for the Moquegua Valley, while his bone oxy-gen isotope value (d18Odrinking water(VSMOW) 5 218.8&) isconsistent with water from higher altitudes. These dataare consistent with a first generation-immigrant fromthe Lake Titicaca Basin, who possibly arrived early inlife, and who had been living in the Moquegua Valley forsome time at the time of death.

Interestingly, both individuals who likely spent theirfirst years of life in the Lake Titicaca Basin are male,while the two individuals who may have moved asadults to the Moquegua Valley from eastern parts ofBolivia are both female. These results contrast withthe presence of females from the Lake Titicaca Basinin the Tiwanaku-affiliated cemetery of Chen Chen inthe Moquegua Valley (Knudson, 2008). If individualswere moving to the Rio Muerto site complex for theexplicit purpose of marriage, this dataset is insuffi-cient to confirm patrilocal or matrilocal residence pat-tern. However, we interpret bone radiogenic strontiumand oxygen isotope ratios, ages-at-death, cranial modi-fication styles, and mortuary treatments as evidencefor at least two males who migrated from the LakeTiticaca Basin as juveniles and at least two femaleswho migrated from the eastern altiplano as adults ofreproductive age. Therefore, this small dataset maysuggest natal family migration from the Lake TiticacaBasin and patrilocal mate exchange with the easternaltiplano or Cochabamba Valley, though we note thatthis is speculative.

Additionally, there are three individuals who exhibitradiogenic strontium isotope values that exhibit interme-diate “nonlocal” 87Sr/86Sr values only in early formingdental elements but not in later-forming skeletal ele-ments. Individual M70-2999 (87Sr/86Sr 5 0.70806) is anadult female with moderate fronto-occipital cranial modi-fication who was buried in tomb 65 of the M70B ceme-tery, adorned with a headdress of orange feathers set incane featherholders, and wearing two plainweave gar-ments of brown camelid wool, one of which had redembroidery and a cotton frog.

Individual M70-4429 (87Sr/86Sr 5 0.70811 LRM1) wasan adult male buried in M70B tomb 95 with a fine inter-locked tapestry-woven tunic with a red field and six ver-tical design bands of Tiwanaku sacrificer figures, as wellas a brown and beige warp striped tunic (Fig. 6). Repre-senting the most highly skilled and labor-intensive tex-tile art of Tiwanaku, tapestry is usually consideredassociated with elite males, and examples are rare inthe Rio Muerto assemblage (Plunger, 2009; Plunger andGoldstein, 2013; Plunger et al., in review). Finally, indi-vidual M43-4835 (87Sr/86Sr 5 0.70814 LLM1) was alargely mummified adult female buried in M43A tomb70. This individual was buried with a feather headdressof at least eight feathers, wearing two warp stripedplainweave tunics with polychrome embroidery, and bur-ied with an embroidered bag and several rolls of cottonthread. These radiogenic strontium isotope data mayrepresent individuals who moved to the Moquegua Val-ley during enamel formation, but resided primarily inthe Moquegua Valley as adults; a shift in oxygen isotopevalues in enamel and bone samples may also indicateincorporation of oxygen from different drinking watersources, or the movement of water in the environment.

Possible evidence for transhumance at the RioMuerto site complex. There are also four individualswho exhibit radiogenic strontium isotope values that arebetween the “local” ranges of the Moquegua Valley andthe Lake Titicaca Basin. Two individuals exhibit inter-mediate “non-local” 87Sr/86Sr values in both dental andskeletal elements and d18Odrinking water(VSMOW) valuesthat are consistent with water sources in the altiplanoand perhaps the Moquegua Valley. Individual M70-2877(87Sr/86Sr 5 0.70803 ULI1, 87Sr/86Sr 5 0.70781, andd18Odrinking water(VSMOW) 5 211.1& L rib 5) was an adultmale with a well-healed fracture of distal radius andulna. This individual was buried in M70B tomb 61wear-ing greenstone beads, a plainweave polychrome stripedtunic with embroidered selvedges, and carrying a poly-chrome warp-striped chuspa, or coca bag, with embroi-dered selvedge. Individual M70-2896(87Sr/86Sr 5 0.70822 LRPM2, 87Sr/86Sr 5 0.70821 andd18Odrinking water(VSMOW) 5 216.0& rib) was an adult

Fig. 6. Right: Rio Muerto site complex Cemetery M70B tomb 95, showing Individual M70–4429. Left: Fragment of tapestrytunic (M70 5 4440) with staff-bearing avian figure buried with Individual M70–4429 (Plunger et al., In review; Photographs byPaul S. Goldstein). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]




male with fronto-occipital cranial modification buried inM70B tomb 54. He was dressed in two tunics and ablanket of warp striped plainweave in natural colors,adorned with a hat and feathers and accompanied byshells and a rare cotton net bag of a type associatedwith shamanic practice (Plunger, 2009). These individu-als’ radiogenic strontium isotope values suggest mobilitybetween different geologic zones throughout their livesthat may be consistent with roles as transhumant pas-toralists or llameros, or caravan drovers, though we notethat this is speculative.

Finally, two individuals are only represented in thisstudy by postcranial skeletal elements. While theirenamel isotopic values are unknown, postcranial skeletalisotopic values indicate that these individuals may haveregularly moved between two geologic and environmen-tal zones. Individual M70-2370 (87Sr/86Sr 5 0.70821 andd18Odrinking water(VSMOW) 5 210.1& R rib 4) is an adultmale buried in M70B tomb 18 with a tunic of light anddark brown stripes with polychrome selvedge embroi-dery, a poorly preserved brown manta and a featheredheaddress. Individual M70-2840 (87Sr/86Sr 5 0.70838 andd18Odrinking water(VSMOW) 5 214.9& R rib 2) was an adultmale buried in M70B tomb 53, a particularly large andcompletely stone-lined chamber that was covered with adome-like arrangement of capstones. This individualwas bound with braided vegetable fiber rope and placedseated facing east, wearing a fine polychrome interlocktapestry tunic and a coarse polychrome dovetail tapestrytunic.

Of the four individuals with intermediate radiogenicstrontium isotope values that may represent repeatedmovement between the Moquegua Valley and the LakeTiticaca Basin, it is notable that all are adult males, andthat all are from the M70 cemetery, the sector of the RioMuerto site that has been associated with a possible pas-toralist occupational specialty (Goldstein, 2005). Addi-tionally, two of these individuals were the only twoindividuals in the M70 cemetery buried wearing tapes-try tunics. This could be interpreted to mean an elitestatus or better access to high status goods for maleswho traveled as juveniles or as adults between the Titi-caca Basin and the Moquegua Valley.

More generally, several distinctions in geographic ori-gins are apparent between individuals buried withindiscrete cemetery groups. Eleven individuals (11/33, or33%) analyzed across all three cemeteries of the RioMuerto site complex spent some portion of their livesoutside of the Moquegua Valley, based on radiogenicstrontium isotope values. In cemetery M43A, only one ofsix individuals analyzed (1/6, or 17%) exhibited“nonlocal” radiogenic strontium isotope values. WithinRio Muerto cemetery M43B, two of seven individualsanalyzed (2/7, or 29%) analyzed demonstrated radio-genic strontium isotope values within or exceeding the“local” range expected for Lake Titicaca Basin (M43-3185 [87Sr/86Sr 5 0.71090 ULM1], M43-4237[87Sr/86Sr 5 0.72018 ULM2, 87Sr/86Sr 5 0.71323 R rib 2]).Cemetery M70B had the highest incidence of “nonlocal”or intermediate radiogenic strontium isotope values,with eight of twenty individuals analyzed (8/20, or 40%)likely to have lived some part of their lives outside ofthe Moquegua Valley. This could be consistent with cem-etery M70B representing a more mobile segment of theoverall population, a higher frequency of first generationmigrants, or both.

CONCLUSION

Overall, the presence of at least one first-generationmigrant from the Lake Titicaca Basin buried at RioMuerto supports the hypothesis that a small Tiwanaku-derived population migrated to Rio Muerto (Goldstein,2005). The presence of small numbers of first-generationmigrants who were likely from both the Lake TiticacaBasin and elsewhere suggests that the Rio Muerto sitecomplex was sustained over generations by local popula-tion growth and a smaller influx of individuals from dif-ferent parts of the Tiwanaku polity, perhaps both asimmigrant families and as marriage partners. However,individuals with intermediate radiogenic strontium iso-tope values who may have traveled frequently betweenthe Lake Titicaca Basin and the Moquegua Valley aremore common than individuals with clearly “non-local”radiogenic strontium isotope values. The four individualswho continued such travel as adults were all males bur-ied in Rio Muerto M70B, supporting their possible iden-tification as interregional elites, herders, or caravandrovers.

In conclusion, we have presented new radiogenic stron-tium and oxygen isotope data from the Middle Horizonarchaeological site complex of Rio Muerto, Peru. The RioMuerto archaeological human enamel and bone valuesrange from 87Sr/86Sr 5 0.7065720.72018, with a mean of87Sr/86Sr 5 0.70804 6 0.00207 (1r, n 5 55). We interpretthese data as evidence of a small number of individualswho lived outside of the Moquegua Valley during enameland/or bone formation, yet were buried in the Tiwanaku-affiliated Moquegua Valley site of Rio Muerto. When con-textualized with other lines of archaeological data, weargue that our person-centered migration historyapproach elucidates movement between different regionswithin the Tiwanaku polity, rather than unidirectionalmovement only from the Lake Titicaca Basin Tiwanakuheartland. Likely interpretations of different individuals’life histories include first-generation migration withnatal families as well as adult transhumance betweenhighlands and lowlands. A subset of samples was ana-lyzed for oxygen isotope values; the data ranges fromd18Ocarbonate(VSMOW) 5 18.1& to 1 27.0& and points tosome variability in the geographic origins of individualsburied at the Rio Muerto site complex. Our analyses ofpaleomobility at the Rio Muerto site complex contributeto an increasingly complex picture of life in the diverseTiwanaku polity.

ACKNOWLEDGMENTS

The authors are very grateful for the researchers andstudents involved in the Rio Muerto Archaeological Pro-ject, our host institution, the Museo Contisuyo ofMoquegua, and particularly Co-director Lic. PatriciaPalacios Filinich, Sarah Baitzel, Alicia Boswell, Eliza-beth Plunger, Lizette Mu~noz, Ulrike Green, BarbaraCarbajal, and Dr. Sara Becker. They also thank person-nel at the W.M. Keck Foundation Laboratory for Envi-ronmental Biogeochemistry at ASU, particularly Drs.Ariel Anbar, Gwyneth Gordon, and Everett Shock, theColorado Plateau Stable Isotope Laboratory at NorthernArizona University, particularly Dr. Bruce Hungate, andthe Elemental and Stable Isotope Analytical UmbrellaCore Facility at UCSD. Finally, this manuscript bene-fited greatly from suggestions from two anonymousreviewers.



LITERATURE CITED

Alcock S, D’Altroy TN, Morrison KD, Sinopoli CM, editors.2001. Empires: archaeological and historical approaches.Cambridge: Cambridge University Press.

Alconini S. 2004. The Southeastern Inka Frontier against theChiriguanos: structure and dynamics of the Imperial InkaBorderlands. Lat Am Antiq 15:389–418.

Andrushko VA, Torres EC. 2011. Skeletal Evidence for IncaWarfare from the Cuzco Region of Peru. Am J Phys Anthropol146:361–372.

Argollo J, Ticcla L, Kolata AL, Rivera O. 1996. Geology, geomor-phology, and soils of the Tiwanaku and Catari River Basins.In: Kolata AL, editor. Tiwanaku and Its Hinterland: Archaeol-ogy and Paleoecology of an Andean Civilization, Vol. 1. Wash-ington, D.C.: Smithsonian Institution Press. p 57–88.

Baitzel SI. 2008. No country for old people: a paleodemographicstudy of Tiwanaku return migration in Moquegua. Peru: Uni-versity of California at San Diego.

Baitzel SI, Goldstein PS. 2011. Manifesting ethnic identity inan ancient society: evidence from a Tiwanaku Cemetery inMoquegua, Peru. In: Hunefeldt C, Zamosc L, editors. Ethnic-ity from Various Angles and Through Varied Lenses: Yester-day’s Today in Latin America. Portland, Oregon: SussexAcademic Press. p 30–44.

Balcaen L, Schrijver ID, Moens L, Vanhaecke F. 2005. Determi-nation of the 87Sr/86Sr isotope ratio in USGS silicate referencematerials by multi-collector ICP–mass spectrometry. Inter JMass Spectrom 24:251–255.

Beasley MM, Bartelink EJ, Taylor L, Miller RM. 2014. Compar-ison of transmission FTIR, ATR, and DRIFT spectra: implica-tions for assessment of bone bioapatite diagenesis. J AchaeolSci 46:16–22.

Becker SK. 2013. Labor and the rise of the Tiwanaku State (AD500–1100): a bioarchaeological study of activity patterns.Chapel Hill: University of North Carolina.

Bellido E, Navarez S, Simons FS. 1956. Mapa geol�ogico delPer�u. Lima: La Sociedad Geol�ogica del Per�u.

Bentley RA. 2006. Strontium isotopes from the earth to thearchaeological skeleton: a review. J Arhcaeol Method Theory13:135–187.

Bentley RA, Price TD, Stephan E. 2004. Determining the"Local" 87Sr/86Sr range for archaeological skeletons: a casestudy from Neolithic Europe. J Achaeol Sci 31:365–375.

Blom DE. 2005. Embodying borders: human body modificationand diversity in Tiwanaku Society. J Anthropol Arch 24:1–24.

Blom DE, Hallgrimsson B, Keng L, Lozada Cerna MC, BuikstraJE. 1998. Tiwanaku ’Colonization’: bioarchaeological implica-tions for migration in the Moquegua Valley, Peru. World Arch30:238–261.

Brettell R, Montegomery J, Evans J. 2012. Brewing and stew-ing: the effect of culturally mediated behaviour on the oxygenisotope composition of ingested fluids and the implications forhuman provenance studies. J Anal At Spectrom 27:778–785.

Buikstra JE, Ubelaker DH, editors. 1994. Standards for datacollection from human skeletal remains: proceedings of aseminar at the field museum of natural history. Fayetteville:Arkansas Archaeological Survey.

Buzon MR, Conlee CA, Bowen GJ. 2011. Refining oxygen iso-tope analysis in the Nasca Region of Peru: an investigation ofwater sources and archaeological samples. Int J Osteoar-chaeol 21:446–455.

Buzon MR, Eng JT, Lambert P, Walker PL. 2005. Bioarchaeo-logical methods. In: Maschner HDG, Chippindale C, editors.Handbook of Archaeological Methods, Vol. 2. Lanham, MD:Altamira Press. p 871–918.

Cabana GS, Clark J, editors. 2011. Rethinking anthropologicalperspectives on migration. Tallahassee: University Press ofFlorida.

Clifford J. 1994. Diasporas. Cult Anthropol 9:302–338.Conlee CA, Buzon MR, Gutierrez AN, Simonetti A, Creaser RA.

2009. Identifying foreigners versus locals in a burial popula-tion from Nasca, Peru: an investigation using strontium iso-tope analysis. J Achaeol Sci 36:2755–2764.

Coplen TB. 1994. Reporting of stable hydrogen, carbon, andoxygen isotope abundances. Pure Appl Chem 66:271–276.

Coudrain A, Loubet M, Condom T, Talbi A, Ribstein P, PouyaudB, Quintanilla J, Dieulin C, Dupre B. 2002. Donn�ees isotopi-ques (87Sr/86Sr) et changements hydrologiques depuis 15 000ans sur l’Altiplano andin (Isotopic Data (87Sr/86Sr) andHydrological Changes during the Last 15,000 Years on theAndean Altiplano). Hydrol Sci J 47:293–306.

Covey RA. 2000. Inka administration of the far south coast ofPeru. Lat Am Antiq 11:119–138.

Craig H. 1961a. Isotopic variations in meteoric waters. Science133:1702–1703.

Craig H. 1961b. Standard for reporting concentrations of deute-rium and oxygen-18 in natural waters. Science 133:1833–1834.

D’Altroy TN. 2002. The Incas. Oxford: Blackwell.Dansgaard W. 1964. Stable isotopes in precipitation. Tellus 16:

436–468.Daux V, L�ecuyer C, H�eran M-A, Amiot R, Simon L, Fourel F,

Martineau F, Lynnerup N, Reychler H, Escarguel G. 2008.Oxygen isotope fractionation between human phosphate andwater revisited. J Hum Evol 55:1138–1147.

Dupras TL, Tocheri MW. 2007. Reconstructing infant weaninghistories at Roman Period Kellis, Egypt using stable isotopeanalysis of dentition. Am J Phys Anthropol 134:63–74.

Evans J, Montegomery J, Chenery CA. 2012. A summary ofstrontium and oxygen isotope variation in archaeologicalhuman tooth enamel excavated from Britain. J Anal At Spec-trom 27:754–764.

Evans JA, Tatham S. 2004. Defining ’local signature’ in termsof Sr isotope composition using a tenth-to twelfth-centuryAnglo-Saxon population living on a Jurassic clay-carbonateTerrain, Rutland, UK. Forensic Geosci 232:237–248.

Faure G. 1991. Principles and applications of inorganic geo-chemistry. New York: Macmillan Publishing Company.

Fenner JN, Wright LE. 2014. Focus: revisiting the strontiumcontribution of sea salt in the human diet. J Achaeol Sci 44:99–103.

Francis PW, Moorbath S, Thorpe RS. 1977. Strontium isotopedata for recent Andesites in Ecuador and North Chile. EarthPlanet Sci Lett 37:197–202.

Gat JR. 1996. Oxygen and hydrogen isotopes in the hydrologiccycle. Annu Rev Earth Planet Sci 24:225–262.

Goldstein P. 1993. House, community and state in the earliestTiwanaku colony: domestic patterns and state integration atOmo M12, Moquegua. In: Aldenderfer MS, editor. Domesticarchitecture, ethnicity, and complementarity in the SouthCentral-Andes. Iowa City: University of Iowa Press. p 25–41.

Goldstein P. 2003. From stew-eaters to maize-drinkers: the Chi-cha economy and the Tiwanaku expansion. In: Bray TL, edi-tor. The archaeology and politics of food and feasting in earlystates and empires. New York: Kluwer Academic/PlenumPublishers. p 143–172.

Goldstein PS. 2000. Communities without borders: the verticalarchipelago and diaspora communities in the SouthernAndes. In: Canuto MA, Yaeger J, editors. The Archaeology ofCommunities: A New World Perspective. London: Routledge.p 182–209.

Goldstein PS. 2005. Andean diaspora: the Tiwanaku coloniesand the origins of South America Empire. Gainesville: Uni-versity Press of Florida.

Goldstein PS. 2009. Diasporas within the Ancient State: Tiwa-naku as Ayllus in Motion. In: Marcus J, Williams PR, editors.Andean civilization: a tribute to Michael Moseley. LosAngeles: Cotsen Institute of Archaeology, University of Cali-fornia Los Angeles. p 277–302.

Grove MJ, Baker PA, Cross SL, Rigsby CA, Seltzer GO. 2003.Application of strontium isotopes to understanding thehydrology and paleohydrology of the Altiplano, Bolivia-Peru.Paleogeograph Paleoclim Paleoecol 194:281–297.

Herring DA, Saunders SR, Katzenberg MA. 1998. Investigatingthe weaning process in past populations. Am J Phys Anthro-pol 105:425–439.



Hillson S. 1996. Dental Anthropology. Cambridge: CambridgeUniversity Press.

Hollund HI, Ariese F, Fernandes R, Jans MME, Kars H. 2013.Testing an alternative high-throughput tool for investigatingbone diagenesis: FTIR in attenuated total reflection (ATR)mode. Archaeomet 55:507–532.

IAEA/WMO. 2006. Global network of isotopes in precipitation.The GNIP Database. Available at: http://isohis.iaea.org. Lastaccessed July 22, 2014.

James DE. 1982. A Combined O, Sr, Nd, and Pb isotopic andtrace element study of crustal contamination in CentralAndean Lavas, I. Local Geochemical Variations. Earth PlanetSci Lett 57:47–62.

Janusek JW. 2008. Ancient Tiwanaku. Cambridge: CambridgeUniversity Press.

Knudson KJ. 2008. Tiwanaku Influence in the South CentralAndes: strontium isotope analysis and middle horizon migra-tion. Lat Am Antiq 19:3–23.

Knudson KJ. 2009. Oxygen isotope analysis in a land of envi-ronmental extremes: the complexities of isotopic work in theAndes. Int J Osteoarchaeol 19:171–191.

Knudson KJ, O’Donnabhain B, Carver C, Cleland R, Price TD.2012a. Migration and viking dublin: paleomobility and paleo-diet through isotopic analyses. J Achaeol Sci 39:308–320.

Knudson KJ, Pestle WJ, Torres-Rouff C, Pimentel G. 2012b.Assessing the life history of an Andean traveler through bio-geochemistry: stable and radiogenic isotope analyses ofarchaeological human remains from Northern Chile. Int JOsteoarchaeol 22:435–451.

Knudson KJ, Price TD. 2007. Utility of multiple chemical tech-niques in archaeological residential mobility studies: casestudies from Tiwanaku- and Chiribaya-affiliated sites in theAndes. Am J Phys Anthropol 132:25–39.

Knudson KJ, Price TD, Buikstra JE, Blom DE. 2004. The use ofstrontium isotope analysis to investigate tiwanaku migrationand mortuary ritual in Bolivia and Peru. Archaeomet 46:5–18.

Knudson KJ, Torres-Rouff C. 2014. Cultural Diversity and Pale-omobility in the Andean Middle Horizon: Radiogenic Stron-tium Isotope Analyses in the San Pedro de Atacama Oases ofNorthern Chile. Lat Am Antiq 25:170–188.

Knudson KJ, Tung T, Nystrom KC, Price TD, Fullagar PD.2005. The origin of the Juch’uypampa cave mummies: stron-tium isotope analysis of archaeological human remains fromBolivia. J Achaeol Sci 32:903–913.

Knudson KJ, Tung TA. 2011. Investigating regional mobility inthe Southern Hinterland of the Wari Empire: biogeochemistryat the site of Beringa, Peru. Am J Phys Anthropol 145:299–310.

Knudson KJ, Webb E, White C, Longstaffe FJ. In press. Base-line data for andean paleomobility research: a radiogenicstrontium isotope study of modern peruvian agricultural soils.Archaeol Anthropol Sci.

Koch PL, Tuross N, Fogel M. 1997. The effects of sample treat-ment and diagenesis on the isotopic integrity of carbonate inbiogenic hydroxylapatite. J Achaeol Sci 24:417–429.

Kolata AL. 1993. The Tiwanaku: portrait of an Andean civiliza-tion. Oxford: Blackwell.

Levinson AA, Luz B, Kolodny Y. 1987. Variations in oxygen iso-topic compositions of human teeth and urinary stones. ApplGeochem 2:367–371.

Longinelli A. 1984. Oxygen isotopes in mammal bone phos-phate: a new tool for paleohydrological and paleoclimatologi-cal research? Geochim Cosmochim Acta 48:385–390.

Lucas CA. 2012. People on the move: examining Tiwanaku stateexpansion in the Cochabamba valley through strontium iso-tope analysis. Flagstaff, Arizona: Northern Arizona Univesity.

Luz B, Kolodny Y, Horowitz M. 1984. Fractionation of oxygenisotopes between mammalian bone-phosphate and environ-mental drinking water. Geochim Cosmochim Acta 48:1689–1693.

Magiligan FJ, Goldstein PS. 2001. El nino floods and culturechange: a late holocene flood history for the R�ıo Moquegua,Southern Peru. Geol 29:431–434.

Magiligan FJ, Goldstein PS, Fisher GB, Bostick BC, MannersRB. 2008. Late quaternary hydroclimatology of a hyper-aridandean watershed: climate change, floods, and hydrologicresponses to the El Ni~no-Southern oscillation in the AtacamaDesert. Geomorphology 101:14–32.

McEwan GF, editor. 2008. The Incas: New Perspectives. NewYork: W.W. Norton.

Meddens FM, Schreiber K. 2010. Inca strategies of control: acomparison of the inca occupations of soras and andamarcalucanas. ~Nawpa Pacha 30:127–166.

Messerli B, Grosjean M, Bonani G, B€urgi A, Geyh MA, Graf K,Ramseyer K, Romero H, Schotterer U, Schreier H, et al.1993. Climate change and natural resource dynamics of theatacama altiplano during the Last 18,000 years: a prelimi-nary synthesis. Mount Res Dev 13:117–127.

Moseley ME, Nash DJ, Williams PR, deFrance SD, Miranda A,Ruales M. 2005. Burning down the brewery: establishing andevacuating an ancient imperial colony at Cerro Baul, Peru.Proc Nat Acad Sci 102:17264–17271.

Munro LE, Longstaffe FJ, White CD. 2007. Burning and boilingof modern deer bone: effects on crystallinity and oxygen iso-tope composition of bioapatite phosphate. Geochim Cosmo-chim Acta 249:90–102.

N�u~nez L, Grosjean M, Cartajena I. 2002. Human occupationsand climate change in the Puna de Atacama, Chile. Science298:821–824.

Ogburn D, Connell S, Gifford C. 2009. Provisioning of the InkaArmy in Wartime: Obsidian Procurement in Pambamarca,Ecuador. J Achaeol Sci 36:740–751.

Pestle WJ, Crowley BE, Weirauch MT. In review. Quantifyinginter-laboratory variability in stable isotope analysis ofancient skeletal remains. PloS One.

Pestle WJ, Weirauch MT, Crowley BE. 2013. InvestigatingInter-Laboratory Variability in Stable Isotope Data. Paperpresented at the American Assosciation of PhysicalAnthropologists.

Placzek CJ, Quade J, Patchett PJ. 2011. Isotopic tracers of pale-ohydrologic change in large lakes of the bolivian altiplano.Quatern Res 75:231–244.

Plunger EM. 2009. Woven connections: group identity, style,and the textiles of the "A" and "B" Cemeteries at the Site ofRio Muerto (M43), Moquegua Valley, Southern Peru. MA The-sis. University of California at San Diego.

Plunger EM, Goldstein PS. 2013. Woman of the cloth: a case ofa possible female specialist group or social category from theM43, M70, and M16 Tiwanaku Cemeteries in Moquegua,Southern Peru. Berkeley, CA: Institute of Andean StudiesConference.

Plunger EM, Goldstein PS, Palacios P. In review. TiwanakuTapestry at the Rio Muerto Site, Moquegua Peru. ~NawpaPacha.

Pollard AM, Pellegrini M, Lee-Thorp JA. 2011. Technical note:some observations on the conversion of dental enamel d18Op

values to d18Ow to determine human mobility. Am J PhysAnthropol 145:499–504.

Price TD, Burton JH, Bentley RA. 2002. The characterization ofbiologically available strontium isotope ratios for the study ofprehistoric migration. Archaeometry 44:117–136.

Price TD, Burton JH, Cucina A, Zabala P, Frei R, Tykot RH,Tiesler V. 2012. Isotopic studies of human skeletal remainsfrom a sixteenth to seventeenth century AD churchyard inCampeche, Mexico: diet, place of origin, and age. CurrAnthropol 53:396–433.

Roberts SB, Coward WA, Ewing G, Savage J, Cole TJ, Lucas A.1988. Effect of weaning on accuracy of doubly labeled watermethod in infants. Am J Physiol 254:R622–627.

Rogers G, Hawkesworth CJ. 1989. A geochemical traverseacross the North Chilean Andes: evidence for crust generationfrom the mantle wedge. Earth Planet Sci Lett 91:271–285.

Sandness K. 1992. Temporal and spatial dietary variability inthe osmore drainage, Southern Peru: the isotope evidence.M.A. thesis. Lincoln: University of Nebraska at Lincoln.

Shemesh A. 1990. Crystallinity and diagenesis of sedimentaryapatites. Geochim Cosmochim Acta 54:2433–2438.



Slovak NM, Paytan A, Wiegand BA. 2009. Reconstructing mid-dle horizon mobility patterns on the coast of Peru throughstrontium isotope analysis. J Achaeol Sci 36:157–165.

Smith C, Nielsen-Marsh C, Jans M, Collins M. 2007. Bone dia-genesis in the European Holocene I: patterns and mecha-nisms. J Achaeol Sci 34:1485–1493.

Stanish C, Vega Edl, Moseley M, Williams PR, Chavez J CVining B, LaFavre K. 2010. Tiwanaku trade patterns inSouthern Peru. J Anthropol Archaeol 29:524–532.

Stein GJ. 2005. The Archaeology of Colonial Encounters. CompPerspect 445.

Stein M, Starinsky A, Goldstein SL, Katz A, Machlus M,Schramm A. 1997. Strontium isotopic, chemical, and sedimen-tological evidence for the evolution of Lake Lisan and theDead Sea. Geochim Cosmochim Acta 61:3975–3992.

Thompson T, Gauthier M, Islam M. 2009. The application of anew method of Fourier transform infrared spectroscopy to theanalysis of burned bone. J Achaeol Sci 36:910–914.

Tomczak P. 2003. Prehistoric diet and socio-economic relation-ships within the Osmore valley of Southern Peru.J Anthropol Archaeol 22:262–278.

Torres-Rouff C. 2002. Cranial vault modification and ethnicityin middle horizon San Pedro de Atacama, Chile. Curr Anth43:163–171.

Torres-Rouff C. 2009. The bodily expression of ethnic identity:head shaping in the Chilean Atacama. In: Knudson KJ, Stoja-nowski CM, editors. Bioarchaeology and Identity in the Amer-icas. Tallahassee: University Press of Florida. p 212–277.

Toyne JM, White CD, Verano JW, Castillo SU, Millaire J-F,Longstaffe FJ. 2014. Residential histories of elites and sacrifi-cial victims at Huacas de Moche, Peru, as reconstructed fromoxygen isotopes. J Achaeol Sci 42:15–28.

Turekian KK, Kulp JL. 1956. Strontium content of humanbone. Science 124:405–407.

Veizer J. 1989. Strontium isotopes in seawater through time.Annu Rev Earth Planet Sci 1:141–167.

Webb E, White C, Longstaffe F. 2013. Dietary shifting in thenasca region as inferred from the carbon- and nitrogen-isotope compositions of archaeological hair and bone.J Achaeol Sci 40:129–139.

Weiner S, Bar-Yosef O. 1990. States of preservation of bonesfrom prehistoric sites in the near East: a survey. J AchaeolSci 17:187–196.

Werner RA, Brand WA. 2001. Referencing strategies and techni-ques in stable isotope ratio analysis. Rapid Commun MassSpectrom 15:501–519.

Wernke S. 2006. The politics of community and inka statecraftin the Colca Valley, Peru. Lat Am Antiq 17:177–208.

Williams PR. 2001. Cerro Ba�ul: a wari center on the Tiwanakufrontier. Lat Am Antiq 12:67–83.

Williams PR. 2002. Rethinking disaster-induced collapse in thedemise of the Andean Highland States: wari and tiwanaku.World Arch 33:361–374.

Wilson AS, Taylor T, Ceruti MC, Chavez JA, Reinhard J,Grimes V, Meier-Augenstein W, Cartmell L, Stern B,Richards MP, Worobey M, Barnes I, Gilbert MTP. 2007. Sta-ble isotope and DNA evidence for ritual sequences in incachild sacrifice. Proc Nat Acad Sci 104:16456–16461.

Wolfe BB, Aravena R, Abbott MB, Seltzer GO, Gibson JJ. 2001.Reconstruction of paleohydrology and paleohumidity fromoxygen isotope records in the Bolivian Andes. PaleogeographPaleoclim Paleoecol 176:177–192.

Wright LE. 2012. Immigration to Tikal, Guatemala: evidencefrom stable strontium and oxygen isotopes. J AnthropolArchaeol 31:334–352.

Wright LE, Schwarcz HP. 1996. Infrared and isotopic evidencefor diagenesis of bone apatite at Dos Pilas, Guatemala: paleo-dietary implications. J Achaeol Sci 23:933–944.

Wright LE, Schwarcz HP. 1998. Stable carbon and oxygen iso-topes in human tooth enamel: identifying breastfeeding andweaning in prehistory. Am J Phys Anthropol 106:1–18.

Wright LE, Schwarcz HP. 1999. Correspondence between stablecarbon, oxygen and nitrogen isotopes in human tooth enameland dentine: infant diets at Kaminaljuy�u. J Achaeol Sci 26:1159–1170.

Wright LE, Vald�es JA, Burton JH, Douglas Price T, SchwarczHP. 2010. The children of Kaminaljuyu: isotopic insight intodiet and long distance interaction in Mesoamerica.J Anthropol Archaeol 29:155–178.



paleomobility in the tiwanaku diaspora: biogeochemical analyses at rio muerto, moquegua, peru

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