title: New dental and isotope evidence of biological distance and place of origin for mass burial groups at Cahokia's mound 72.
abstract: OBJECTIVE
  Mound 72 at Cahokia figures prominently into interpretations of early Mississippian sociopolitical development. A previous study utilizing dental morphology concluded that the groups of mostly young adult females interred in four mass graves in Mound 72 were likely not from Cahokia and possibly reflect sacrificial offerings from outside communities. The purpose of this study is to reevaluate these findings using multiple indicators of biological relatedness and place of origin/migration.
  
  
  METHODS
  Biological relatedness in Mound 72 was examined using dental metrics and morphology. Four additional archaeological samples from nearby sites were included to better assess biological variation within Mound 72. Strontium isotope analysis (87Sr/86Sr) was also conducted on individuals from several burial features in Mound 72 to determine heterogeneity in place of origin.
  
  
  RESULTS
  Biodistance studies indicate that individuals in the four mass graves are phenotypically similar to other groups in the region, whereas F229-lower, a burial group with an aberrant mortuary context, is phenotypically distinct. Strontium isotope analyses show that mean Sr signatures for each feature investigated fall within the established local range for Cahokia. However, the range of Sr ratios for individuals in F229-lower is very narrow, suggesting they reflect a single population from a limited geologic region.
  
  
  CONCLUSIONS
  Collectively, these results question the long-standing idea that individuals in the four mass graves were non-local to Cahokia and suggest that F229-lower contained a biologically dissimilar group that either came from an outside region with a similar Sr signature to Cahokia, or represent a distinct and restricted group from the region. Am J Phys Anthropol 158:341-357, 2015. © 2015 Wiley Periodicals, Inc.
authors.affiliation: Department of Biomedical Sciences, West Virginia School of Osteopathic Medicine, Lewisburg, WV.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Thompson
authors.affiliation: Illinois State Archaeological Survey, Prairie Research Institute, University of Illinois Urbana Champaign, Champaign, IL.
authors.forename: Kristin M
authors.initials: KM
authors.lastname: Hedman
authors.affiliation: Illinois State Archaeological Survey, Prairie Research Institute, University of Illinois Urbana Champaign, Champaign, IL.|Department of Anthropology, University of Illinois Urbana Champaign, Urbana, IL.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Slater
keywords: Mississippian; biological variation; dental anthropology; migration; strontium isotope analysis