Hunter-gatherers in Siberia died of a plague outbreak 5,500 years ago

Plague outbreaks killed hunter-gatherer groups in southeastern Siberia approximately 5,500 years ago, according to DNA evidence extracted from the teeth of victims. Researchers, including Ruairidh Macleod from the University of Oxford, sequenced bacterial DNA from Yersinia pestis at four ancient burial sites near Russia's Lake Baikal. This discovery marks the earliest documented plague outbreak and the oldest strain of Y. pestis ever sequenced. Previously, scientific understanding suggested that early strains of Y. pestis lacked the genetic factors for high lethality and that plague primarily impacted humans with the advent of settled farming communities living in close proximity to rats and domesticated animals. The findings challenge these long-held theories about the disease's origins and early evolution.