Strontium-scapes, cultural change, and human life histories in the southern Andes

BARBERENA, RAMIRO; PETRUS LE ROUX; AGUSTO TESSONE ; GASCO, ALEJANDRA; CARINA LLANO; GUSTAVO LUCERO; LUIS CORNEJO ; VÍCTOR DURÁN; CORTEGOSO, VALERIA; FERNANDA FALABELLA; CECILIA FRIGOLÉ; ERIK MARSH; CÉSAR MÉNDEZ; AMALIA NUEVO DELAUNAY ; LORENA SANHUEZA; FRANCISCA SANTANA SAGREDO ; ANDRÉS TRONCOSO; DIEGO WINOCOUR

Dublin

Congreso; INQUA 2019; 2019

International Union for Quaternary Research

The maingoalofthispaperistoreconstructthespatialscales andpatternsoforganizationof humanmobilityacrossa diverse arrayofecologicalandaltitudinalsettingsacrossthesouthern Andes(32º-34ºS)duringthelast2500years.Thisprojectis designed to sampledifferent biogeographic regions from the Pacific coast inChileto the Eastern Andeanlowlandsin Argentina(Figure1).Toachievethis long-termgoal,wepresentadvancesinthefollowingtwo specific goals of theproject. Firstly,weseektobuildaframeworkof bioavailablestrontiumisotopes(87Sr/86Sr)as expressedinthemain Andeangeologicalunits,whichspanfromthePliocenetothe Lower Paleozoic:a)marineSrinthePacificcoast;b)Coastal Cordillera(Cretaceous);c)Western PrincipalCordillera(Miocene-Oligocene);d)EasternPrincipalCordillera(Cretaceous-Jurassic); e) FrontalCordillera(Permian-Triassic);f)Precordillera(LowerPaleozoic);and e) ActiveForeland (Quaternary)(Figure2).Toachievethisgoal, we analyzeplantsandrodentsamplesfrom modernandarchaeological contexts. Thisisthefirstattempttoapplysuchanapproach in the southern Andes.Secondly,byanalyzingstrontiumisotopesinhumanboneand teethsamplesfrom archaeologicalcontexts,wereconstructplaceof originanddeath,providingananalytical windowforthestudyof individuallifehistories,combiningtherealmsofquotidianranges of humanmovementandsocialprocesses,suchasconflictand migration,whichdisruptthis patternofdailylife.Wefocusonthe analysisofhumanremainsfromthelast2500years,witnessingthemostintenseprocessesofsocio-demographicand economicchange,including anapparentreductioninthe intensity ofmobility,firstpresenceofarchaeologicalcemeteries, the origins of agro-pastoraleconomies,andthegeographicexpansionoftheInka Empire. Fromamethodologicalperspective,wedevelopa preliminary comparisonofstrontiumand oxygenisotopes(18O/16O),revealing a divergentpattern:whileoxygenisotopesforhuman samplesfrom distantregionsinwesternArgentinaoverlapwidely,thereare important differencesinstrontiumisotopes,hencesuggestingthat strontiumprovidesafinertracerof humanmobilityacrossthis geologicallycomplexAndeanlandscape.Ourstrontiumresultswill bebrieflycomparedtothoseproducedbycolleaguesforthe south-centralAndesofsouthern Peru,northernChile,andwestern Bolivia, in anattempttolearnaboutthespatialresolution achievablein different Andeangeologicalsettings.Insynthesis,byintegratingthe resultsfor bioavailablestrontiumandhumantissuesinthecontextof a biogeographicframework,this project(NationalGeographicHJ-136R-17) presentsthefirstassessmentofsociocultural variation,scalesof humanterritories,andpatternsofsocialinteractionacrossthe southern Andes.