A 20-million-year-old flea encased in amber is likely carrying a bacteria closely related to the Bubonic Plague, which is also referred to as the "Black Death."
According to Discovery News, a new study on the bacteria is published in the Journal of Medical Entomology. The bacteria found was an ancient strain of Yersinia pestis, which led to the deadly bacterial infection.
Yersinia pestis led to three types of plague, the Black Death chiefly among them. Inactive since 1959, per the World Health Organization, the Bubonic Plague killed 30 million people in Europe in the 14th century.
"Aside from physical characteristics of the fossil bacteria that are similar to plague bacteria, their location in the rectum of the flea is known to occur in modern plague bacteria," study lead author George Poinar, Jr., an entomology researcher in the College of Science at Oregon State University, said in a press release. "And in this fossil, the presence of similar bacteria in a dried droplet on the proboscis of the flea is consistent with the method of transmission of plague bacteria by modern fleas."
Fleas were a common source of the Bubonic Plague, as they would infect small animals and, in turn, humans.
"If this is an ancient strain of Yersinia, it would be extraordinary," Poinar said. "It would show that plague is actually an ancient disease that no doubt was infecting and possibly causing some extinction of animals long before any humans existed. Plague may have played a larger role in the past than we imagined.
"Since the dried droplet with bacteria is still attached to the tip of the proboscis, the flea may have become entrapped in resin shortly after it had fed on an infected animal.
"This might have been one of the rodents that occurred in the Dominican amber forest. Rodent hair has been recovered from that amber source."
