Bats are the only mammals capable of sustained flight rather than simple gliding.

The longer version

Other mammals glide, stretching a membrane between limbs to travel from tree to tree, but none can generate lift through flapping. Bats do, using a wing formed from an enormously elongated hand whose finger bones support a thin, flexible membrane.

That membrane is active rather than passive. Muscles and elastic tissue within it change shape during each stroke, and tiny sensors detect airflow so the wing can adjust instantly. Powered flight is expensive, so bats pair it with a high metabolic rate, an efficient heart and, in many species, the ability to enter torpor when conditions turn cold or prey disappears.

Where this entry sits

This collection gathers small surprises about mammals, reptiles, amphibians, birds, fish, insects, and the pets living alongside people. Expect odd details about senses, anatomy, and everyday behaviour that many people never notice in the animals around them. The full list sits on the Animals page, where every entry is listed in order.