The rodents, known variously as “land pigeons” or “the poor man’s dog,” may be in the process of being vindicated for one of their longest-standing charges: that they were the principal vectors of the bubonic plague, or the Black Death, which ravaged Europe for 400 years or so starting in 1347.
But a new study from the University of Oslo traces the roots of the disease back to gerbils from Asia, rather than rats. “If we’re right,” Professor Nils Christian Stenseth of the University told the BBC, “we’ll have to rewrite that part of history.”
Stenseth and his colleagues researched weather patterns (via tree-ring records) in Europe and Asia around the time of plague outbreaks, and they believe that their findings let rats off the hook. (Incidentally, the real culprit in the spread of the plague were fleas: Rats and gerbils were merely the vehicles that transmitted the fleas to humans.)
“We show that wherever there were good conditions for gerbils and fleas in central Asia, some years later the bacteria shows up in harbor cities in Europe and then spreads across the continent.”
In conclusion, down with gerbils. Rats forever.