A delicate but exquisitely preserved skull of a raven-sized bird with a sickle-like beak that inhabited Madagascar 68 million years ago shows scientists that they learned a lot about bird diversity during the dinosaur era.
Scientists on Wednesday said the bird, named Falcatakely forsterae, possessed a face unlike any other known bird from the dinosaur era – the Mesozoic era – not only in the shape of its beak but in its underlying anatomy.
Its beak superficially resembled that of a small toucan although the two species were not closely related. While modern birds exhibit a wide variety of beak shapes – from sword-billed hummingbirds to rhino hornbills – little of that diversity has been discovered among Mesozoic birds.
The 9 cm Falcatakely skull remains partially embedded in the rock because scientists did not want to risk damaging it. Instead they analyzed it using sophisticated scanning and digital reconstruction. Only his skull was found.
“Incredible, small, delicate, fragile, challenging to study – all at the same time,” said University of Ohio anatomy professor Patrick O’Connor, lead author of the research published in the journal Nature.
“Bird fossils are particularly rare in part because they have such delicate skeletons. Hollow bones are not great for surviving the fossilization process, ”added paleontologist and study co-author Alan Turner of Stony Brook University in New York.
“For this reason, we need to be aware that we are probably downsampling the diversity of Mesozoic birds. A recently discovered species like Falcatakely provides a glimpse of the tantalizing possibility of greater diversity of forms waiting to be discovered, ”Turner said.
Birds evolved from small feathered dinosaurs around 150 million years ago. The early birds retained many ancestral features, including teeth. The Falcatakely fossil has a single conical tooth at the front of the upper jaw. Falcatakely probably had a small number of teeth on his waist.
It belonged to an avian group, the enantiornithines, which did not survive the mass extinction of 66 million years ago, ending the Cretaceous period.
“Unlike early birds like Archeopteryx, which in many ways still looked like dinosaurs with their long tails and unspecialized snouts, enantiornithins like Falcatakely would have looked relatively modern,” Turner said.
It was in the underlying skeletal structure where its differences were most evident, O’Connor added, with more similarities to dinosaurs like the Velociraptor than to modern birds.