Broad-billed parrot sketch actually shows that the wings are not particularly short. They appear broad, as they commonly are in forest-adapted species, and the alula appears large, a feature of slow-flying birds. Its sternal keel was reduced, but not enough to prevent flight, as the adept flying "Cyanoramphus" parrots also have reduced keels, and even the flightless kakapo, with its vestigial keel, is capable of gliding. Furthermore, Hoffman's account states that it could fly, albeit with difficulty, and the first published illustration shows the bird on top of a tree, an improbable position for a flightless bird. The broad-billed parrot may have
Kakapo non-dispersive sex when food is plentiful. A female kakapo will likely be able to produce eggs even when there are few resources, while a male kakapo will be more capable of perpetuating the species when there are plenty, by mating with several females. This supports the Trivers–Willard hypothesis. The relationship between clutch sex ratio and maternal diet has conservation implications, because a captive population maintained on a high quality diet will produce fewer females and therefore fewer individuals valuable to the recovery of the species. The beak of the kakapo is adapted for grinding food finely. For this reason, the