14C data and the early colonization of Northwest South America: A critical assessment

The aim of this paper is to make a critical appraisal of the available 14 C dataset from Northwest South America (Colombia) corresponding to the Pleistocene/Holocene transition (ca. 12,000e8000 14 C years BP). The first step in the study was to assemble from both published and unpublished sources an exhaustive database of 14 C dates (n ¼ 85), recording data regarding the environmental setting and spatial coordinates of each site, stratigraphic provenance of the dated samples, material used for dating, and 14 C dating method. After the application of different filtering procedures based on outlier detection tech- niques, the database was subsequently reduced (n ¼ 77). Using uncalibrated and calibrated dates, some spatial and temporal trends in data distribution were investigated in order to illustrate both the strengths and weaknesses of the available database. It is concluded that three main features that characterize the 14 C dataset from Northwest South America, namely the very high percentage of 14 C measurements made