Biological affinities and regional microevolution among pre-Hispanic communities of Colombia's Northern Andes

Dental non-metric data were used to examine the biological continuity of pre-Hispanic peoples of Colombia's Northern Andes, including highland, lowland and coastal peoples. This report contributes to studies regarding the peopling of South America by establishing a benchmark comparison that includes pre-Hispanic populations of the Northern Andes. The sample consisted of a total of 583 individuals from 56 cemeteries ranging in time from the Early Holocene (10,000 BP) to the Final Late Holocene (500 BP). Permanent dentitions from individuals between 5 and 40 years of age were scored for 87 dental traits based on the ASUDAS. A divergence matrix was programmed using the Smith's Mean Measure of Divergence equation (MMD). Bartlett's adjustment and Ascombe transformation were considered into MMD calculations. Principal Coordenate analysis was applied based on MMD matrix scores. A clear group was found that associated Initial Late Holocene samples with Final Late Holocene samples. Early Holocene samples are very different to that, and Middle Holocene samples show as morphologically intermediate series. A comparison of the frequencies by time and period showed that a limited biological continuity existed. Interbreeding among initial populations of the same regions is expressed in similar frequencies of dental traits within Early Holocene and Middle Holocene samples. Early Holocene samples did not match with Sinodont pattern according to discriminant function analysis. These findings help us to better understand the settlement process of human groups in the Northern Andes and its relationship with migratory movements in South America.