Ancient Siberian graves reveal oldest plague outbreak, reshaping its origin story

A Nature study of four Siberian graves near Lake Baikal, dating to about 5,500 years ago, found Yersinia pestis DNA in roughly 40% of the remains, offering the oldest evidence of plague and suggesting two prehistoric outbreaks that spread within families among hunter‑gatherers. The bacterium likely caused pneumonic plague at the time—not the flea‑borne bubonic form that emerged later—and the findings challenge the idea that the Neolithic agricultural shift was the primary driver of plague emergence, showing it could affect hunter‑gatherer communities as well.