Summary:
- This article discusses how the evolution of a pandemic bacterium, Yersinia pestis, which causes the plague, has been shaped by the loss of certain genes over time.
- Researchers found that as Y. pestis adapted to spread more efficiently between humans, it lost genes that were important for its survival in other environments, like the flea that typically carries the bacteria.
- The gene loss allowed Y. pestis to become a more specialized and deadly pathogen, highlighting how evolutionary changes can make some bacteria more dangerous during pandemics.