Study Shows Rats Did Not Cause The Plague
Boris Schmid led a team from the Nils Stenseth from University of Oslo went out to find rodent reservoirs of recurrent plague emergence by looking at climate fluctuations that occurred before big outbreaks. 7,711 historical outbreaks and 15 tree-ring climate records from Europe and Asia were examined. They wrote that variable climate conditions that have a role in wildlife outbreaks of plague in Asia were now identified in Juniper tree rings from northern Pakistan’s Karakorum Mountains.
Kazakhstan had warmer springs and wetter summers which can lead to increases in the density of gerbils and their fleas. As gerbil populations decrease as temperatures drop, fleas then go out to different hosts. “We have previously shown that an increase of 1 degree Celsius doubles the prevalence [of plague] in wild rodents in central Asia,” Stenseth tells New Scientist.