With over 1,500 species, bats account for more than one fifth of all living mammal species2. They are distributed globally, are predominantly nocturnal and adapted to diverse foraging niches, ranging from insectivorous, sanguivorous, carnivorous, piscivorous, frugivorous and nectarivorous species1. Some species are exceptionally long-lived compared with other mammals of similar body size, capable of living 8–10 times longer than expected, showing few signs of ageing or cancer3. Several species host a diversity of viruses without overt disease symptoms and show unique immune adaptations4,5. Despite having the smallest mammalian genomes (approximately 2 Gb), they harbour a diverse endogenous genomic virosphere4,6 and many have active DNA transposons, which is exceptionally rare among mammals7. The acquisition and evolution of these unique traits have been the centre of heated debates, particularly in relation to the evolution of flight and echolocation. This is probably due to the difficulties in reconstructing bat evolutionary history8,9,10. Challenges have stemmed from: homoplastic and convergent molecular and morphological characters11,12; conflicting phylogenetic signals13; a paucity of chromosome-level bat genome assemblies1,14; rapid speciation events resulting in incomplete lineage sorting and introgression15; the dearth of phylogenetic methods required to handle this complexity; and a limited and fragmented fossil record16. Indeed, the fossil record...

1h 33m | R