Scientists have identified the fossilized remains of a bird that, with a wingspan of more than 7 meters (23 feet), could have been the largest bird that ever existed on Earth, Proceedings of the National Academy of Sciences reported.
The remains were found in 1983 in South Carolina by Charleston Museum volunteer James Malcom during excavations directed by Albert Sanders for a new terminal at the international airport of that city.
The creature, named by scientists as Pelagornis sandersi, was undoubtedly an extremely efficient glider with long, slim wings that helped it remain in the air despite its size, researchers said.
The species was so big - twice as large as the royal albatross, the largest living flying bird - that researchers had to dig up its remains with a power shovel.
The article says that scientists figure the bird lived between 28 and 24 million years ago, that is, after dinosaurs became extinct and before the first humans populated the region.
Those birds existed in all parts of the planet for tens of millions of years, but vanished some 3 million years ago during the Pliocene Epoch.
Paleontologists have not yet determined the cause of their extinction.
The remains of Pelagornis sandersi include thin, hollow bones, short legs and enormous wings, from which one can deduce that the bird was not very elegant on land but was a marvel in flight.
The question challenging scientists is how a creature could take flight and stay in the air when its size and weight exceed the maximums considered possible for flying birds.