The kokako, a bird with an Yma Sumac-like range

The kokako is a very curious bird from New Zealand, of so ancient a lineage that it is certain that it has been in this country since before the time when New Zealand first became an oceanic island or archipelago. Its ancestor probably became isolated when the super continent, Gondwanaland, began to fragment some 80 million years ago. It is found nowhere else in the world, nor does it have any obvious living relatives. The dawn chorus of the kokako was a common sound in the forest before European settlement. The incredibly beautiful melodious organ-like notes hang over the valley before being answered by another of its kind, somehow enhanced and made more poignant by the dark brooding quality of the bush. Male and female may sing together for periods of up to half an hour, performing a duet of impressive harmony and complexity. Neighbouring kokakos may join in singing the same themes, resulting in a rondo-like chorus. In addition to song, kokakos communicate with a variety of calls, clicks, buzzes, cat–like noises and screeches, all used in particular social contexts. According to a recently published document, less than 400 pairs of kokakos currently exist.