# Bayesian Inference of Sex-Specific Mortality Profiles and Product Yields from Unsexed Cattle Zooarchaeological Remains

## TL;DR

This paper introduces a Bayesian method to estimate sex-specific mortality and productivity in ancient cattle using archaeological data, revealing insights into prehistoric farming practices.

## Contribution

A novel Bayesian inference approach to derive sex-specific survival curves from unsexed cattle remains, enabling productivity estimates in zooarchaeology.

## Key findings

- The Bayesian model successfully infers sex-specific survival curves from unsexed cattle remains.
- Estimated productivity parameters suggest potential improvements in prehistoric slaughter management.
- Application to Neolithic sites reveals variations in herd productivity across Europe.

## Abstract

Zooarchaeological age-at-death profiles for domesticated ruminants can be inferred from tooth eruption, replacement, and wear. These profiles contain important information on slaughter management and have been used informally to infer the goals of past husbandry strategies. In principle, sex-specific survival curves could inform on various productivity parameters, including herd growth rates and sustainability, milk and meat yields, macronutrient and calorie yields, and feed consumed. Knowledge of these parameter values would allow identification of differences in husbandry economics in different archaeological contexts. However, archaeological age-at-death profiles are rarely sex-specific and are often derived from small sample sizes. As such, challenges remain in inferring sex-specific survival curves using explicit models that account for sampling uncertainty. We present a Bayesian inference approach for inferring sex-specific survival curves from unsexed cattle zooarchaeological age-at-death profiles that can accommodate data from any combination of age class boundaries. Our approach relies on the assumption that asymmetric sex-specific slaughter leads to a change in sex ratio over time, which we inform from slaughter practices in modern unimproved cattle herds. By combining inferred sex-specific archaeological survival curves with ethnographic productivity data from modern unimproved cattle, we are able to estimate herd growth rate, milk and meat yields, macronutrient and calorie yields, and feed consumed per animal. We apply our approach to zooarchaeological age-at-death profiles previously proposed to prioritise milk or meat production and to a set of profiles from ten Neolithic sites located across Europe. We infer that there was scope for improvement in prehistoric slaughter management.

The online version contains supplementary material available at 10.1007/s10816-025-09749-x.