The fossils found in Antarctica represent the oldest giant members of an extinct group of birds that patrolled the southern oceans. Their wingspan reached 6.4 meters. This is twice the size of today’s largest bird to date, the wandering albatross. An article that reveals more details about the life of individuals that have now turned into fossils is published in Scientific Reports.
The huge birds of the pelagornitids have traveled extensively across the oceans of the Earth for at least 60 million years. While a much smaller pelagornitid fossil dates back 62 million years ago, one recently described fossil – a piece of a bird’s paw 50 million years old – shows that the larger pelagornitids arose just afterlife recovered from the mass extinction 65 million years ago, when relatives died out. birds 3 dinosaurs. The second pelagornithid fossil, part of the jawbone, dates from about 40 million years ago.
“Our discovery of fossils with a wingspan of 5 to 6 meters shows that birds evolved to truly gigantic proportions relatively quickly after the extinction of the dinosaurs and ruled the oceans for millions of years,” explains Peter Kloss, a graduate student at the University of California, Berkeley.
The last known pelagornitid appeared 2.5 million years ago, during climate change when the Earth cooled down and the ice age began.
Pelagornitids look quite intimidating, not only because of the huge wingspan. They are known as “sharp-toothed” birds because of their bony protuberances that resemble sharp teeth. Although these are not real teeth like those of humans and other mammals. The bony protrusions were covered with a horny material, keratin, which is similar to our nails. These pseudo-teeth have helped birds catch squid and fish in the sea when they may have hovered over most of Earth’s oceans for weeks.
The fossils that paleontologists describe are among many collected in the mid-1980s from Seymour Island off the Antarctic Peninsula. These findings were subsequently moved to the University of California Berkeley Museum of Paleontology. After analyzing the fossil samples later, scientists came to the conclusion that one of the parts of the fossils – the fossil foot bone, tarsometatarsus – came from an older geological formation than was originally thought. Thus, the age of the fossil was about 50, not 40 million years. This is the largest specimen of the entire extinct group of pelagornitids.
In another newly discovered fossil, the middle part of the lower jaw, parts of a pseudo-tooth are preserved; during the life of the bird, they would be up to 3 cm in size. The remaining part of the jaw, approximately 12 cm long, was obtained from a very large skull, which would be up to 60 cm in length. Using measurements of the size and distance between these teeth and an analytical comparison with other pelagornitid fossils, the authors proved that the fragment came from a single bird. As large, if not larger, than the largest known bone-toothed skeletons.