Scientists have discovered the oldest known evidence of the plague bacterium, *Yersinia pestis*, in the remains of individuals buried in Siberia. The discovery pushes back the known timeline of the plague’s existence by approximately 200 years, indicating it was present as early as 5,500 years ago. Analysis of ancient DNA extracted from skeletal remains revealed the genetic markers of the plague. This finding challenges previous assumptions about the disease’s origins and spread, suggesting it emerged earlier than previously believed. Researchers believe this ancient strain of the plague may have contributed to later, more widespread epidemics. The discovery provides valuable insights into the evolutionary history of this devastating disease and its impact on early human populations. Further research aims to understand how the plague evolved and spread across Eurasia.