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How are bats related to rodents and other mammals?

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bat Livingstone's fruit bat (*Pteropus livingstonii*) in flight.

It is a common misconception that bats are related to rodents; in fact, bats are not even remotely related to mice, rats, or other members of the order Rodentia.1

Bats belong to their own distinct order, Chiroptera, which is the second-largest order of mammals, surpassed only by rodents in the number of species. While it was once theorized that bats were closely related to primates, modern genome analysis has placed them in a different superorder that includes animals such as pangolins and whales.1

Because the fossil record for bats is limited due to their tiny, delicate bones, their exact evolutionary history remains complex. It is believed that bats evolved from flightless insectivores, with fully developed flight capabilities appearing by the Eocene Epoch, approximately 45 million years ago. Today, bats are recognized as the only mammals capable of true flight.123