A closer look

Epidemiologists don't just guess where a pandemic started; they use hardcore math to rewind a virus's family tree. By combining geographic location data with viral DNA mutations, researchers use Bayesian phylogeography to map exactly how pathogens like Ebola spill over from bats and travel across human borders. This statistical time-travel assigns probabilities to every possible route of infection, allowing us to pinpoint the precise forest clearing where the outbreak began.