Maybe It Was Gerbils Spreading Black Death

From the Feb. 26, 2015, Chicago Tribune "Oh, rats!  Study cites gerbils for Black Death" by Sarah Kaplan, Washington Post.

Scientists now say that it was not the much-maligned black rat that spread that horrible disease across Europe eight centuries ago.  They have identified a new culprit, that favorite little pet, the gerbil.

A climate study of 14th-century Europe contradicts the notion that the plague outbreaks were caused by disease-carrying fleas hosted by the continent's rats.  In order for the rats to have spread it, you would have needed warm summers with little precipitation..  But, there is no relationship between them.

"Instead, the Black death, as the epidemic was known, seemed to be tied to the climate in Asia.  Analysis of 15 tree-ring records, which document yearly weather conditions, shows that Europe always experienced plague outbreaks after central Asia had a wet spring followed by a warm summer -- terrible conditions for black rats, but ideal for Asia's gerbil population."

Numbers of gerbils increased and they carried their bacteria-laden fleas to Europe along the Silk Road arriving a few years later to clobber Europe's population.  Over 100 million died in the "Second Plague pandemic" in the mid-14th century.  It continued to recur until the 1800s.

Beware the Horrible Gerbil.  --DaCoot