New study finds gerbils, not rats, were to blame for Black Death outbreaks

Looks like we owe some rats a very belated apology.

A new study published in the Proceedings of the National Academy of Sciences suggests that gerbils, not black rats, were to blame for recurring epidemics of the bubonic plague across Europe.

"If we're right, we'll have to rewrite that part of history," professor Nils Christian Stenseth, of the University of Oslo and an author on the study, told BBC News.

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Scientists originally thought that recurrences of the Black Death — which began in the 14th century — were caused by infected rats; humans became sick when fleas jumped from their rodent hosts onto people. But by analyzing tree-ring records in Europe against the timelines of plague outbreaks, researchers now believe gerbils, which thrive during wet springs followed by warm summers — the same weather conditions that matched up with outbreaks — were the plague-carrying problem.

"Whenever 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," Stenseth said.

Sorry, rats. Thanks a lot, gerbils.