The specimens were lost during World War II and relocated in 2011, when researchers returned to the midden and found another two graves. The first two hunter-gatherer graves were found in 1875 in a shell midden, an ancient pile of waste like mussel shells and fish bones, in Riņņukalns, Latvia. pestis couldn’t really drive big outbreaks,” says lead author Ben Krause-Kyora, a biochemist and archaeologist at Christian-Albrecht University of Kiel, to Nicola Davis at the Guardian.

Compared to the strain of bacteria that caused the infamous Black Death in the 14th century, the ancient microbe seems to lack the genes that would have enabled it to spread quickly from person to person.

Genetic analysis suggests the bacteria itself may have evolved about 7,000 years ago. Scientists found a strain of the plague bacteria in 5,000-year-old human remains. The bacteria that causes the bubonic plague ( Yersinia pestis) may be about 2,000 years older than previously thought, according to a new study published on Tuesday in the journal Cell Reports. Ancient DNA and proteins gathered from the specimen's bones and teeth revealed the presence of Yersinia pestis.

Black death game