In just four years in the mid-fourteenth century, the medieval pandemic of 'Black Death' killed 17-28 million Europeans, or 30-40% of the total population. Further resurgences later in the century eliminated 90% of the households around Montpellier in southern France. It is in this region that Raoult et al. went searching for the causative agent of the Black Death. Although this agent has been presumed to be
Some genetically engineered mice harbor unwanted mutations that hitchhike alongside desired modifications, affecting experimental outcomes.