Gender-associated infant mortality in archaeological samples

For decades, a peculiar phenomenon has been described in bioarchaeology: The analysis of skeletons from prehistoric and historical burial sites often reveals a very unexpected sex ratio characterized by a clear surplus of buried men and a lack of buried women. Attempts to explain this phenomenon have so far been unsatisfactory. For example, errors in sex determination, a faster decomposition process of female skeletons, or separate burial sites for men and women have been discussed. A lack of women has also been proven in Roman period cemeteries in what is now Austria, such as the eastern burial area of Roman Ovilava, today`s Wels in Upper Austria. Here, twice as many skeletons classified as male were found as female. A female deficit of this magnitude is highly unusual for a civilian town like Ovilava and contradicts all biological expectations - the natural sex ratio at the time of birth is 105 biologically male newborns to 100 biologically female newborns. The higher mortality of male children leads to an even gender ratio in young adulthood and ultimately to a surplus of women in later adulthood. This typical pattern of contemporary societies does not apply to certain prehistoric and historical populations. This interdisciplinary project aims to examine a different explanation for the lack of women in Roman cemeteries: It is assumed that the female sex had a lower value in Roman society, which led to a preference for male children from birth onwards and systematic neglect of female children. It is therefore assumed that there was a pronounced disadvantage for girls in Roman society, which led to increased mortality among the female sex, ultimately resulting in a lack of women in adulthood. To test this assumption, the skeletons of children and adolescents buried in the eastern cemetery of the Roman city of Ovilava between the 1st and 4th century AD were examined. It is not possible to determine the sex of children and adolescents based on skeletal features alone, which is why the biological sex of 57 children and adolescents is to be determined with the help of genetic analyses (aDNA). The subsequent step is then to clarify whether female and male children were buried in different cemetery areas. Furthermore, the different treatment of girls and boys could manifest itself in different dietary patterns and an increased disease burden. In addition, it is assumed that the mortality rate of girls increased in phases of crises that shook Roman society, such as climatic changes, wars, and pandemics. The skeletons will therefore be dated by applying C14-analysis to be able to assign them to the various crisis phases during the period of Roman rule in todays Austria. Consequently, the project should help to clarify possible discrimination against female children in Roman times.