Sorry about that, rats. Scientists say we’ve been crediting the wrong vermin for the spread of the Black Death. While rats have historically been blamed for bringing the plague epidemic to Europe from Asia in 1347, killing millions of people over some 400 years, gerbils are the actual culprits. Prof. Nils Christian Stenseth of the University of Oslo led a study that concluded the weather conditions in Asia during the time the plague spread between the two continents would have been more conducive to gerbils. “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,” Stenseth told the BBC.