Scientists have discovered that Australia was once inhabited by a variety of giant birds – including a kangaroo-sized flying turkey – which roamed the continent more than two million years ago.

The finding was based on an analysis of fossils and bones found in 1880 which have long been thought to belong to a “giant ancestral pigeon”.

But a fresh examination revealed that the remains belonged to five separate species of giant megapodes. One of the species was a turkey-like creature which weighed up to 18 lbs and was four times the size of the modern brush turkey.

“It's been quite surprising,” Elen Shute, a researcher from Flinders University, told ABC News.