Kakapo its specific epithet "habroptilus" comes from "habros" "soft", and "ptilon" "feather". The bird has so many unusual features that it was initially placed in its own tribe, Strigopini. Recent phylogenetic studies have confirmed the unique position of this genus as well as the closeness to the kākā and the kea, both belonging to the New Zealand parrot genus "Nestor". Together, they are now considered a separate superfamily within the parrots, Strigopoidea, the most basal of all living parrots. Within the Strigopoidea, the kakapo is placed in its own family, Strigopidae. The common ancestor of the kakapo and the genus "Nestor"
Flightless bird the lineage. This indicates that the distinctive flightless nature of ratites is the result of convergent evolution. Two key differences between flying and flightless birds are the smaller wing bones of flightless birds and the absent (or greatly reduced) keel on their breastbone. (The keel anchors muscles needed for wing movement.) Adapting to a cursorial lifestyle causes two inverse morphological changes to occur in the skeleto-muscular system: the pectoral apparatus used to power flight is paedorphically reduced while peramorphosis leads to enlargement of the pelvic girdle for running. Repeated selection for cursorial traits across ratites suggests these adaptions comprise a