Adzebill

Aptornis otidiformis
Aptornis defossor The adzebills (genus Aptornis) were two closely related bird species, the North Island Adzebill (Aptornis otidiformis Owen 1844) and the South Island Adzebill (Aptornis defossor Owen 1871) of the extinct family Aptornithidae (Mantell 1848). The family was endemic to New Zealand, has been placed, by various studies of morphology and DNA, variously close to and far off from the Kagu of New Caledonia, as well as the trumpeters in the order Gruiformes. Its morphological closeness to the kagu may be the result of convergent evolution, although New Zealand's proximity to New Caledonia and shared biological affinities (the two islands are part of the same microcontinent ) has led some researchers to suggest they share a common ancestor from Gondwana.

In life the adzebills were massive gruiforms, the size of small moas (with which they were initially confused with on their discovery) with enormous downward pointed bill. They were flightless, having very reduced wings (smaller for their size than those of the dodo), and strong legs. The two species varied mostly in size, the North Island Adzebill being the smaller species. Their fossils have been found the drier areas of New Zealand, and only in the lowlands. Richard Owen, who described the two species, speculated that it was an omnivore, and analysis of its bones by stable isotope analysis has seemingly confirmed this. They are thought to have fed on large invertebrates, lizards, tuataras and even small birds.

The adzebills were never as common as the moas, and subjected to the same hunting pressure as the moas and other large birds by the settling Polynesians, they went extinct before the arrival of European explorers. Their remains have been found in archeological sites across New Zealand.

References

• Worthy, Trevor H., & Holdaway, Richard N. (2002) The Lost World of the Moa, Indiana University Press:Bloomington, ISBN 0-253-34034-9

External links

• Site with image