The secret to a longer, healthier life may lie in the DNA of bats, which are known for their extraordinary longevity compared to their body size. These flying mammals, some of which can live over 50 years, appear to have evolved powerful immune defenses and unique ways of eliminating damaged cells. These traits may help them avoid diseases like cancer and stay healthy for decades. Scientists are now studying bat DNA to uncover genetic strategies that could one day help improve human health as people age. To explore this, Juan Manuel Vazquez, a postdoctoral fellow at the University of California, Berkeley, collected tissue samples from various bat species across the Western U.S. Using mist nets set up near water sources at night, his team captured bats, took small biopsy samples, and released them. Their focus was on the genus Myotis, which includes some of the longest-living bat species. One example is Brandt’s myotis, a species that was recaptured 50 years after being banded in Europe. In a recent study published in Nature, Vazquez and his colleagues analyzed the genomes of eight Myotis species. They found a strong link between lifespan and immune function, with longer-lived bats having more genes related to fighting cancer. The research also showed that genes involved in aging overlap with those responsible for disease defense, suggesting that understanding one could provide insights into the other. In the lab, Vazquez tested bat cells by exposing them to harmful chemicals and observed that the longest-lived species, the little brown bat, responded by activating genes that promote cell death rather than those that repair DNA. This suggests that bats may use different strategies to eliminate damaged cells. Bats have thrived for millions of years and now make up 20% of all mammal species, living on every continent except Antarctica. Among these, the Myotis genus includes species with vastly different lifespans—some can live over 50 years, while others only about seven. Their immune systems are also unique, allowing them to host many viruses without getting sick. This ability may explain why some viruses, including those related to the coronavirus that causes COVID-19, can jump from bats to humans. Researchers believe that bats' intense physical activity and strong immune defenses are connected, and that their genetic makeup helps them both fight viruses and live longer. Vazquez and his colleagues continue to study these genetic mechanisms, hoping to apply their findings to human health and disease prevention.