Dromornithidae

Dromornithidae, known as mihirungs (after Tjapwuring Mihirung paringmal, "giant bird") and informally as thunder birds or demon ducks, is an extinct family of large, flightless birds native to Australia from at least the late Oligocene (and perhaps as early as the early Eocene) to the Late Pleistocene. They were long classified in Struthioniformes (the ratites), but are now usually classified as a type of gigantic fowl (Galloanserae). Dromornithids were part of the Australian megafauna. One species, Dromornis stirtoni, was tall, making them among the largest birds ever. Only a single species, Genyornis newtoni survived into the Late Pleistocene. They are thought to have been herbivorous.

==Classification== The scientific name Dromornithidae derives from the Greek words , ("swift-running") and , ("bird"). The family was named by Max Fürbringer in 1888, citing W. B. Clarke and Gerard Krefft, Owen's separation from "Dromaeus" and Dinornis, and a note by von Haast allying Dromornis with Dromaeus. What the nearest relatives of this group are is a controversial issue. For many years it was thought that dromornithids were related to ratites, such as emus, cassowaries, rheas and ostriches. It is now believed that the similarities between these groups are the result of similar responses to the loss of flight. The latest idea on dromornithid relationships, based on details of the skull, is that they evolved early in the lineage that includes waterfowl (Anseriformes). However, some phylogenetic studies have recovered them as closer to gamefowl (Galliformes).