Prehistoric dental calculus gives evidence for coca in early coastal Ecuador

Los CERRITOS, a late Chorrera (Engoroy) cemetery on the Santa Elena Peninsula of Ecuador yielded artefacts and radiocarbon assay which indicate that use of the site began about 840 BC and continued for several years within the Late Formative 1 . The human skulls from the site are of particular interest because many showed heavy accumulations of supragingival dental calculus (tartar), which contrast with the relatively slight calculus accumulations on the teeth of skulls recovered from the earlier Valdivia (3000–1500 BC) site of Real Alto 2 , also on the Santa Elena Peninsula. We argue here that the heavy calculus accumulations are the result of habitual, secular coca chewing in late Chorrera times. This diagnosis, in turn, supports the hypothesis of prehistoric trade in coca, probably in exchange for mollusc shells, with inhabitants of the eastern Andean slopes.