Animal-borne diseases have ruled the news cycle recently—from Zika and Ebola to SARS and MERS. However, little is known about the spread of these diseases in their animal hosts. More perplexing, the mechanisms that lead to human outbreaks remain elusive. Dr. Dan Salkeld of Colorado State University hopes to change that through the study of plague—the disease responsible for the Black Death in the Middle Ages. Plague is now a worse problem for the prairie dogs that Salkeld studies than it is for humans, but understanding its unique ecology may shed light elsewhere. By using plague and its complex, multispecies dynamics as a model, Salkeld hopes that we can achieve key insights into why, how, and when diseases like Ebola and Middle Eastern Respiratory Syndrome spill over into human populations.