Bats have long fascinated researchers with their uncanny ability to tolerate lethal viruses that would devastate other species.
A sweeping study of more than 500 vesper bat species has now uncovered a striking explanation buried in their genes.
These bats, it turns out, possess two entirely separate sets of antibody genes, a genomic architecture without precedent among mammals.
Antibodies are the immune system's precision weapons, tailored to recognise and neutralise a vast array of pathogens.
By maintaining a duplicated genetic toolkit, bats may be able to mount broader and more adaptable defences than any other mammal.
This revelation not only rewrites part of the textbook on mammalian immunity but also carries tangible medical promise.
Scientists suspect that decoding the bat's strategy could inspire innovative drugs and vaccines for people.
In effect, the very animals we once feared as reservoirs of disease may hold clues to conquering it.