Birds are often associated with flight, but not all of them take to the skies. Around 60 species — fewer than 1% of all bird ...

New Zealand's unique flightless nocturnal birds, like the kiwi and kakapo, showcase the country’s rich biodiversity.

If these birds can't fly, how did they spread across the globe? The standard explanation is that their common ancestor, also flightless, once roamed all over a southern supercontinent called Gondwana.

More than 99% of birds can fly. But that still leaves many species that evolved to be flightless, including penguins, ostriches, and kiwi birds. In a study in the journal Evolution, researchers ...

More than 99% of birds can fly. But that still leaves many species that evolved to be flightless, including penguins, ostriches, and kiwi birds. In a new study in the journal Evolution ...