On a winter's night in the Western United States, a team of Berkeley students stretched fine mist nets across a dark stream, waiting for a creature that may secretly hold the keys to a longer human life. They caught bats, took tiny wing biopsies, and let them fly off — and the DNA those samples revealed is now reshaping how scientists think about growing old.
Biologist Juan Manuel Vazquez was fascinated by the puzzle during his graduate studies at the University of Chicago: bats, relative to their body size, live astonishingly long lives. Yet almost no genomic data existed to explain why. So after he joined UC Berkeley as a postdoctoral fellow in 2020, he set out across the region with undergraduates to gather tissue samples from these remarkable mammals, focusing on the genus Myotis.
The payoff, published in the journal Nature, is the first analysis of eight Myotis genomes. It points to a powerful connection between lifespan and the immune system. The longer-lived bats carried higher levels of genes linked to fighting cancer, and the researchers found striking overlap between genes tied to aging and genes involved in disease defense. The lesson, Vazquez suggests, is that aging and infection may not be as separate as we once believed.
The most surprising clue came from the laboratory. Vazquez, who now keeps cell cultures from 259 individuals across 32 species, exposed cells from the little brown bat (Myotis lucifugus) — North America's longest-lived bat — to toxic chemicals that cause severe damage. Instead of switching on DNA-repair genes, the cells did the opposite: they ramped up activity that promotes cell death. "The longest-lived bat in North America decides 'I can't save this ship' and immediately switches gears to prioritize killing off the damaged cells," Vazquez said.
Remarkably, that exact strategy is shared by another long-lived, cancer-resistant animal: the elephant. When a cell is too damaged to save, both creatures kill it before it can turn dangerous — a simple but powerful defense against disease.
Bats have been thriving for roughly 60 million years and today make up about 20% of all mammal species. Among the 1,511 known bat species, around 139 belong to Myotis, a group where close relatives can have wildly different lifespans. Brandt's myotis can survive half a century, while the black Myotis of South and Central America lives only about seven years — a gap Vazquez compares to a relative living nine times longer than modern humans.
Understanding these strategies, says Berkeley professor Peter Sudmant, could help us live fuller, healthier lives. "If you start looking at long-lived species like elephants, whales and bats, you start finding ways that nature has actually already resolved a lot of these problems in human health," Vazquez added.