An intact skull of Australian megafauna bird Genyornis newtoni has finally been discovered, revealing that the ancient creature resembled a giant goose.
Genyornis was first discovered more 128 years ago. The only previously known fossil of the species was found in 1913 but was badly damaged. Now, a skull fossil described in a Historical Biology paper, provides new insight into the ancient bird.
Today, the largest bird is the ostrich which weighs up to 150kg, followed by the emu and cassowary which can reach more than 70kg.
But up until recently megafauna birds around the globe were much bigger. Much. Much bigger.
Among extinct giant birds are Madagascar’s elephant birds, Aepyornis, New Zealand’s moa, and “terror birds” like Dromornis. The largest grew to more than 800 kg in weight. The terror birds had giant, razor sharp beaks used for hunting and slicing their prey, recalling their dinosaur ancestors.
Genyornis was giant, at an estimated 230kg, but much less is known about what it looked like and how it lived. The species went extinct about 45,000 years ago.
The new Genyornis skull was found at South Australia’s (SA) Lake Callabonna in 2019 along with near complete fossils of the body. And it shows that Australia’s megafauna bird is unlike any other.
“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 first author Phoebe McInerney, a palaeontologist at SA’s Flinders University.
It also has a surprisingly large brain case and unusual casque (enlargement of the bone) on top of its head.
The ancient bird’s skull shares similarities with modern waterfowl including the Australian magpie goose.
“The exact relationship of Genyornis within this group has 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,” McInerney adds.
“We were particularly excited to discover the first fossil upper bill of Genyornis, for the first time we could put a face on this bird, one very different to any other bird, yet like a goose” says senior author Trevor Worthy, also from Flinders.
The authors found further evidence that Genyornis was well adapted to aquatic habitats. It had protection against an influx of water through its ears and throat.
Genyornis, the new skull reveals, was basically a giant prehistoric goose.
Shedding light on Genyornis in such great detail provides palaeontologists a glimpse into how the animals lived, and may even give some insights into why they went extinct.