Kakapo "The Unnatural History of the Kakapo" won two major awards at the Reel Earth Environmental Film Festival. Two of the most significant documentaries, both made by NHNZ, are "Kakapo – Night Parrot" (1982) and "To Save the Kakapo" (1997). The BBC's Natural History Unit also featured the kakapo, including a sequence with Sir David Attenborough in "The Life of Birds". It was also one of the endangered animals Douglas Adams and Mark Carwardine set out to find for the radio series and book "Last Chance to See". An updated version of the series has been produced for BBC TV, in
Flightless bird free to increase in abundance until the population was limited by food and territory. A study looking at energy conservation and the evolution of flightlessness hypothesized intraspecific competition selected for a reduced individual energy expenditure, which is achieved by the loss of flight. Some flightless varieties of island birds are closely related to flying varieties, implying flight is a significant biological cost. Flight is the most costly type of locomotion exemplified in the natural world. The energy expenditure required for flight increases proportionally with body size, which is often why flightlessness coincides with body mass. By reducing large pectoral muscles