Australasian Science: Australia's authority on science since 1938

Australia’s Giant Flightless Fowl’s Far-Flung Family

The full text of this article can be purchased from Informit.

Australia’s giant mihirungs (Dromornithidae) were flightless fowl that included some of the most massive birds in the world, such as the horse-sized Dromornis stirtoni, which tipped the scales at 650 kg. But what were they related to?

In a new analysis published in Royal Society Open Science, palaeontologists from Flinders University and Argentina have revealed that these birds share their evolutionary roots with the giant Gastornis species in the Northern Hemisphere. Together they form a major lost branch on the evolutionary tree of fowl: chickens and ducks.

This group lived in Australia from 55 million years ago until becoming extinct about 50,000 years ago. When the last one died an entire taxonomic order, and some of the most spectacular birds ever to have lived, disappeared.

How did giant birds disperse across both hemispheres? The scientists suggest that small flying birds gave rise to giant flightless fowl twice – once in Australia and again in the Northern Hemisphere. “They form a neat parallel to how we now understand the ratites (emu, ostrich and kin) evolved,” says study leader A/Prof Trevor Worthy of Flinders University.

“At the base of the family tree of giant flightless ratites on each continent we now know there was a small flying bird like a tinamou. These dispersed across the oceans, settled on a continent, evolving into huge...

The full text of this article can be purchased from Informit.