# Genetic research on Yersinia pestis evolution > Live situation record from CLSTR: https://clstr.news/situations/genetic-research-on-yersinia-pestis-evolution > Updated: 2026-09-30T00:22:15.000Z. Sources: 9. Developments: 2. Genetic research into the bacterium Yersinia pestis is providing new insights into why the Black Death and subsequent outbreaks recurred for centuries following the initial 14th-century pandemic in Europe and Eurasia. An international research team, led by scientists from the University of Tartu, analyzed 26 genomes from 11 archaeological sites across Estonia, Russia, England, the Netherlands, and Switzerland. By combining radiocarbon dating with genetic chronologies and historical records, researchers reconstructed the pathogen’s evolution. The study, published in PNAS, refined the dating for a total of 75 plague genomes. The research indicates a major diversification of genetic lineages between 1450 and 1500. This suggests the bacteria could persist in environments among rodents and their parasites, creating new disease reservoirs that allowed the plague to periodically re-emerge in human populations until the 18th century. Scientists suggest the spread of the disease was likely influenced by environmental changes, such as droughts, and large-scale population movements. ## Timeline ### 2026-09-30: University of Tartu study reveals plague persisted in Europe for 400 years A DNA study led by the University of Tartu shows the plague persisted in Europe for 400 years after the Black Death, evolving into new genetic lineages through the 18th century. 7 sources. https://clstr.news/cluster/research-reveals-plague-persisted-in-europe-for-centuries-after-black-death ### 2026-09-21: Genetic traces explain why the Black Death recurred for centuries Genetic studies of Yersinia pestis reveal how the plague persisted and recurred across Europe and Eurasia for centuries by evolving and circulating among animal populations. 2 sources. https://clstr.news/cluster/genetic-traces-explain-why-the-black-death-recurred-for-centuries --- Cite as: Genetic research on Yersinia pestis evolution. CLSTR, https://clstr.news/situations/genetic-research-on-yersinia-pestis-evolution