HUMAN EVOLUTION × GENETICS

The Black Death

1347 to 1352 CE

Phanerozoic · Cenozoic · Quaternary · Holocene · Meghalayan

A bacterium killed something like half of Europe in five years. Seven centuries later it was identified by sequencing it out of the teeth of the people it killed, buried in a London plague pit, and the strain was traced back to a cemetery in the Tian Shan mountains where the epidemic seems to have started.

Why it matters

The deadliest documented event in human history, and the first pandemic whose cause was named by reading the dead rather than the records. What was recovered was not a trace of the disease but the pathogen's own genome, which is how the same method has since been turned on plagues nobody could identify at all.

Dating & uncertainty

The dates come from written records. What ancient DNA added is the culprit, Yersinia pestis, sequenced from the teeth of London plague victims, and a source region traced to fourteenth-century central Eurasia.

Sources

1. Bos et al. (2011), Nature · A draft genome of Yersinia pestis from victims of the Black Death
2. Spyrou et al. (2022), Nature · The source of the Black Death in fourteenth-century central Eurasia
3. Keller et al. (2019), PNAS · Ancient Yersinia pestis genomes from across Western Europe reveal early diversification during the First Pandemic

Earth history as one day

23:59:59.9913 ms before midnight

if Earth’s 4.54 billion years were compressed into a single day