Kakapo became isolated from the remaining parrot species when New Zealand broke off from Gondwana, around 82 million years ago. Around 30 million years ago, the kakapo diverged from the genus "Nestor". Earlier ornithologists felt that the kakapo might be related to the ground parrots and night parrot of Australia due to their similar coloration, but this is contradicted by recent studies; rather, the cryptic colour seems to be adaptation to terrestrial habits that evolved twice convergently. The kakapo is a large, rotund parrot; the adult can measure from in length, and weight can vary from at maturity. Males are larger
Kakapo have a polygynous lek breeding system. It is also possibly one of the world's longest-living birds. Its anatomy typifies the tendency of bird evolution on oceanic islands, with few predators and abundant food: a generally robust physique at the expense of flight abilities, resulting in reduced wing muscles and a diminished keel on the sternum. Like many other New Zealand bird species, the kakapo was historically important to Māori, the indigenous people of New Zealand, appearing in many of their traditional legends and folklore; however it was also heavily hunted and used as a resource by Māori, both for its