Bats are the only mammals that can fly. Scientists have therefore been eager to learn how they evolved from their terrestrial ancestors. Until recently, however, even the oldest fossil bats still looked essentially like modern bats. New fossils have revealed a species that is helping to connect the dots between bats and their nonflying forebears.
Findings from genetics and developmental biology have further illuminated bat origins, elucidating their place in the mammal family tree and the process by which the bat wing may have evolved.