Timpson, A. | Search bioRxiv

bioRxiv2025

Improving archaeological metadata reporting in human paleogenomicstudies

Paleogenomic research has dramatically increased our understanding of past demographic and adaptive processes, but has also been criticized for a perceived disconnect between geneticists and other parties involved in the study of the past. For interdisciplinary research to be productive, contextual metadata associated with paleogenomic samples should be accessible in the same publication. Here, we conduct a pilot study examining the extent of archaeological metadata reporting in 30 peer-reviewed human paleogenomic studies, based on genetic sequences from 3911 ancient humans predominately from Western Eurasia, published between 2013 and 2024. We show inconsistent reporting of archaeological data across studies, and have sought to identify the driving factors. Overall, we found no strong explanatory variables, though some metadata fields - like Geolocation - have improved in completeness over time. These inconsistencies mean that metadata reporting is often insufficient to directly investigate the relationship between patterns of cultural and genetic change on the basis of published data alone. We propose a minimum information checklist as a best-practice guideline for collecting and reporting archaeological data in the future.

genomics↗

bioRxiv2024

Lethal Plague Outbreaks in Lake Baikal Hunter-gatherers 5500 Years Ago

The rise of zoonotic diseases in prehistory is often associated with the Neolithic agricultural transition1,2. In particular, plague has been linked to population declines in Late Neolithic Europe3,4. Although plague is amongst the most devastating diseases in human history, early strains of Yersinia pestis, the causal agent of plague, lack virulence factors required for the bubonic form5, and their severity remains unclear. Here, we describe the oldest strains of plague reported so far, associated with two early phases of outbreaks among prehistoric hunter-gatherers in the Lake Baikal region in East Siberia, beginning from [~]5600-5400 years ago (cal. BP). These outbreaks occur across four hunter-gatherer cemeteries; the largest of these (Ust-Ida I) has a 38.7% detection rate for plague infection (39% detection across all sites). By reconstructing kinship pedigrees, we show that small familial groups are affected, consistent with human-to-human spread of the disease, and the first outbreak occurred within a single generation. Intriguingly, the infections appear to have resulted in acute mortality events, especially among children. Zoonotic transmission is separately indicated by a Brucella infection in one of the children. Interestingly, we see differences in functional genomic variants in the prehistoric plague strains, including in the ypm superantigen known from Y. pseudotuberculosis today. The new strains diverge ancestrally to all known Y. pestis diversity and push back the Y. pestis divergence from Y. pseudotuberculosis by some 2000 years6. Our results show that plague outbreaks happen earlier than previously thought and that these early outbreaks were indeed lethal. The findings challenge the common notion that high population densities and lifestyle changes during the Neolithic transition were prerequisites for plague epidemics.

genetics↗