Madagascar Cretaceous bird had a sickle-shaped beak | Paleontology

Paleontologists in Madagascar have identified a new genus and species of enantiornithine bird that had a long, deep beak, a morphology hitherto unknown in Mesozoic birds.

Falcatakely forsterae surrounded by non-avian dinosaurs and other animals from Madagascar’s Late Cretaceous period. Image credit: Mark Witton.

The newly identified bird species lived between 70 and 68 million years ago (Late Cretaceous) in present-day Madagascar.

Appointed Falcatakely forsterae, it belongs to the Enantiornithines, an extinct group of birds known exclusively from the Cretaceous and mainly from fossils discovered in Asia.

“Enantiornithins represent the first great diversification of early birds, occupying ecosystems alongside their non-avian relatives such as Velociraptor and TyrannosaurusSaid Dr Alan Turner, researcher in the Department of Anatomical Sciences at Stony Brook University.

“Unlike the first birds, such as Archeopteryx, with long tails and primitive features in the skull, enantiornithins like Falcatakely forsterae would have looked relatively modern.

Reconstruction of the life of Falcatakely forsterae with its unique beak. Image credit: Mark Witton.

Falcatakely forsterae was small, about the size of a crow, and had a sickle-shaped beak.

“We don’t really know why certain beak shapes evolve, but we do know that they are used for a multitude of functions such as handling objects, grooming feathers, feeding and other vital behaviors,” Dr Turner said.

“In the case of Falcatakely forsterae, it was probably the same thing and it is important to discover that this early riser in the Cretaceous had such an evolved beak.

Falcatakely forsterae is known from a well-preserved partial skull found in northwestern Madagascar.

“The exquisite quality of the preservation is exceptional and reveals many important details,” said the paleontologists.

“For example, a complex series of grooves on the outer surface of the bones making up the side of the face indicate that the animal has harbored an expansive keratin cover, or beak, throughout life.”

Reconstruction of the life of Falcatakely forsterae. Image credit: Mark Witton.

Using high-resolution micro-calculated tomography and digital modeling, they practically dissected individual bones from the rock.

“It quickly became apparent that the bones making up the face Falcatakely forsterae are organized unlike those of any dinosaur, avian or non-avian, although they have a superficially similar face to a number of modern bird groups living today, ”they said.

“All living birds build the skeleton of their beak in a very specific way. It is mainly formed by a single enlarged bone called the premaxilla.

“In contrast, most birds of the dinosaur age, like the iconic Archeopteryx, have a relatively unspecialized muzzle composed of a small premaxilla and a large maxilla.

“Surprisingly, in Falcatakely forsterae we found this primitive bone arrangement similar, but with a general face shape reminiscent of some modern birds with a high and long upper beak and completely different from anything known in the Mesozoic.

“It turns out that you can make a modern looking mouthpiece in a number of ways,” Dr. Turner said.

“The basis for the development of the skeleton of modern beaks did not have to be there for a ‘modern’ looking beak to evolve.”

The discovery is described in a journal article Nature.

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PM O’Connor et al. A bird from the Upper Cretaceous of Madagascar reveals a unique development of beaks. Nature, published online 25 November 2020; doi: 10.1038 / s41586-020-2945-x