A human skull from the Yamnaya, a nomadic Bronze Age people from western Russia. Scientists theorize that plague epidemics may have enabled the Yamanaya and other groups of people to move into new territories. Image courtesy of Rasmussen, et al.
The Black Death has been infecting people centuries before the well-known 14th-century epidemic in Europe. In a new study reported in the journal Cell, researchers report that the bacterium Yersinia pestis, was infecting people as long as 5,000 years ago.
Read more in The New York Times.