Genyornis newtoni: The Giant Goose of Prehistoric Australia

Australia’s prehistoric plains once hosted a golden era of enormous flightless birds. Among them was the “Demon Duck of Doom”, which roamed what is now the Northern Territory about 15 million years ago.

Scientists now say there is room for another creature in our affections: a truly colossal bird that appears to have looked rather like a present-day goose - only, of course, much bigger.

Genyornis newtoni has been known to science for a long time. The species disappeared roughly 45,000 years ago and was originally described in 1913.

Reaching up to 2.25 metres tall and weighing as much as 230 kilograms, Genyornis newtoni would have cut an imposing figure in the grassland environments it favoured across a huge area of Australia.

However, a recent find indicates that scientists may have misunderstood this bird.

Genyornis newtoni skull offers a clearer picture

Palaeontologists have found a nearly complete, articulated skull of Genyornis newtoni. It is only the second skull ever recovered for the species. The first, which formed the basis of the 1913 description, was, with no disrespect intended, in exceptionally poor condition.

For the first time, researchers can properly examine the animal’s head - and it was an extraordinary one. The fossil shows that Genyornis would have been conspicuous among other birds, with an appearance markedly unlike that of its nearest relatives.

Its skull featured a very large braincase, substantial jaws and a triangular bony crest known as a casque. Indeed, certain characteristics of the Genyornis newtoni skull aligned not with its closest relatives, but with early waterfowl lineages that were diverging at the time.

Its bill resembled those of birds still seen today, including the Australian magpie goose (Anseranas semipalmata).

“Genyornis newtoni had a tall and mobile upper jaw like that of a parrot but shaped like a goose, a wide gape, strong bite force, and the ability to crush soft plants and fruit on the roof of their mouth,” says Flinders University palaeontologist Phoebe McInerney.

“The exact relationships of Genyornis within this group have been complicated to unravel, however, with this new skull we have started to piece together the puzzle which shows, simply put, this species to be a giant goose.”

The team scanned the fossil to produce a detailed three-dimensional reconstruction. They could then compare it with the skulls of living birds, helping them determine how the Genyornis head may have worked and how it might have appeared beneath its more modest covering of flesh, skin and feathers.

“The form of a bone, and structures on it, are partly related to the soft tissues that interact with them, such as muscles and ligaments, and their attachment sites or passages,” says Flinders University palaeontologist Jacob Blokland.

“Using modern birds as comparatives, we are able to put flesh back on the fossils and bring them back to life.”

Evidence for a giant goose adapted to water

The evidence appears to settle the matter. This giant bird possessed several adaptations associated with aquatic environments.

The arrangement of its ear meant the canal would have been shielded from water when Genyornis dipped its head below the surface. Its bill was structured to provide similar protection for its throat. The bill’s form also suggests it was well suited to gripping and tearing aquatic vegetation.

If that interpretation is correct, it may help account for the extinction of Genyornis. The freshwater habitats in which it would have prospered have since turned saline, radically changing the ecosystem.

Further detailed study - and, ideally, the discovery of additional fossils - will probably reveal more. Even so, it is remarkable to finally gain a clearer understanding of this extraordinary species.

Picture the scene. It is dawn in a grassy swamp, with mist drifting over the land. The first shafts of sunlight rise above the horizon and the landscape begins to wake. Across the water, birds start calling.

“HONK,” trumpets Genyornis. “HONK. HOOOOONK.”

Magnificent.

The research has been published in Historical Biology.