Kakapo relative wing size of any parrot. Its wing feathers are shorter, more rounded, less asymmetrical, and have fewer distal barbules to lock the feathers together. The sternum is small and has a low, vestigial keel and a shortened spina externa. As in other flightless birds and some flighted parrots, the furcula is not fused but consists of a pair of clavicles lying in contact with each coracoid. As in other flightless birds, the angle between the coracoid and sternum is enlarged. The kakapo has a larger pelvis than other parrots. The proximal bones of the leg and arm are disproportionately
Kakapo and was well adapted to avoid the birds of prey which were their only predators. As well as the New Zealand falcon, there were two other birds of prey in pre-human New Zealand: Haast's eagle and Eyles' harrier. All these raptors soared overhead searching for prey in daylight, and to avoid them the kakapo evolved camouflaged plumage and became nocturnal. When a kakapo feels threatened, it freezes, so that it is more effectively camouflaged in the vegetation its plumage resembles. Kakapo were not entirely safe at night, when the laughing owl was active, and it is apparent from owl nest