Microstructural findings on prenatally formed dental enamel support the assumption of an Iron age twin burial from Germany

Abstract

Only a few cases of twins have been reported in the bioarchaeological literature so far and their identification is usually prompted by the find situation. A confirmation of this assumption by purely gross-morphological methods is not reliable. More recently, aDNA analysis constitutes a more promising approach, although the preservation of the DNA can be a limiting factor. Here we present an alternative approach to test the twin hypothesis, based on the microscopic analysis of the pattern of incremental markings in prenatally formed dental enamel.

Three corresponding pairs of teeth from two perinatal human individuals from the Iron Age in Germany were chosen for microscopic analysis of their prenatal enamel. In all analyzed teeth, four accentuated incremental lines (AILs) with matching locations between the corresponding teeth were identified. The numbers of daily enamel growth increments between corresponding consecutive AILs was (almost) identical in the individuals.

Our results strongly suggest that the individuals shared a common intrauterine environment and therefore constitute twins. We conclude that the microscopic analysis of prenatally formed dental enamel is a powerful approach to test a twin sibling hypothesis in archaeological cases.