Ostriches, emus, cassowaries, rheas, and kiwis can't fly. Unlike most birds, their flat breastbones lack the keel that anchors the strong pectoral muscles required for flight. Their puny wings can't possibly lift their heavy bodies off the ground. ... (Read "Big Bird" in National Geographic magazine.)

How did Emus lose the ability to fly?

Changes in regulatory DNA, not gene mutations, are the culprit, scientists say. FLIGHTLESS FANCY Emus (one shown with a chick) and related birds may have lost the ability to fly because of changes in DNA that regulates genes.

Can Emus fly at all?

The emu has wings and feathers, but he can't fly. He's the second largest bird on earth, after the similarly flightless ostrich and is native to Australia. Emus were once able to fly, but evolutionary adaptations have since robbed them of that gift.