The plague-causing bacterium may have first come to Europe with the large-scale migration of steppe nomads in the Stone Age, millennia before the first known historical epidemics. Findings also confirm plague bacteria undergoing genetic mutations related to its virulence at the time of its arrival.

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The plague-causing bacterium may have first come to Europe with the large-scale migration of steppe nomads in the Stone Age, millennia before the first known historical epidemics. Findings also confirm plague bacteria undergoing genetic mutations related to its virulence at the time of its arrival.