The large beak of this ancient bird breaks new ground in the fossil record

Every day, scientists discover surprising new information that reshapes our understanding of the ancient world.

The latest groundbreaking discovery concerns a late Cretaceous bird with a very large beak – so large that it traces a new course in evolutionary history.

In a study published Wednesday in Nature, researchers describe a hitherto unknown species, Falcatakely forsterae, an ancient bird with an unusually large beak resembling that of a modern toucan.

Big bird – Researchers discovered the fossil of this unknown bird species ten years ago in Madagascar.

But the fossil specimen was fragile and contained many small bones, so it was not fully analyzed until 2017. But once the researchers analyzed the tiny fragments, they realized they had unearthed something really special. .

“As soon as we started carefully removing the stone from around those delicate bones, it really quickly became apparent that it was like, ‘Oh, okay, we’ve got something really neat here'” “, Patrick O ‘ Connor, lead author of the study and professor of anatomical sciences at Ohio University, recounts Reverse.

After removing the rock, the scientists used micro-computed tomography scanners to collect data to simulate the creature’s skull in 3D. They then used 3D printing to build a replica of the bird skull.

“There’s a lot of digital modeling that’s just about figuring out, you know, what the anatomy of this new animal is,” O’Connor says.

The researchers named the species Falcatakely (which roughly means “little flying sickle”) for her uniquely shaped face. They classified Falcatakely as an enantiornithine bird, a “group of birds that were alive in the days of dinosaurs,” says O’Connor. These birds often had teeth and claws on their wings. All known species are now extinct.

Again, Falcatakely is different from most other ancient birds that also lived 65 to 250 million years ago. Although birds of this era – known as the Cretaceous – have varied body shapes, when it comes to their faces, they tend to look the same.

Face time – But with its long and deep beak, Falcatakely broken the mold.

“We see Falcatakely has an extremely divergent face shape from anything it’s related to, ”says O’Connor.

The large beak of this bird is more like that of modern birds.

It is a curious discovery. Modern birds are much more diverse than the ancients when it comes to their faces. Anatomy can help explain the difference between most ancient birds – apart from Falcatakely – and modern ones. It all comes down to one bone in their skull: the premaxillary bone. Located at the top of a bird’s beak, ancient birds do not appear to have used this bone for food, unlike modern birds.

“All of this diversity in the shape of the modern bird face is really driven by a bone called the premaxilla bone,” says O’Connor. “And it’s the bone that does all this crazy differentiation through development to give you this vast array of face shapes that we see around us today.”

Stimulated by the Falcatakely Unique face shape, the researchers wanted to understand “what drives the shape of the face, not just in modern birds and in enantiornithin birds,” according to O’Connor.

They compared the bone structure of the newly discovered bird to other creatures, including non-avian creatures, like dinosaurs.

“We take a broader perspective to say, okay, we can look at a whole range of animals that are relatively closely related to each other. Some of them are modern birds, some are Mesozoic birds, and then those non-avian dinosaurs which are the closest relatives of avian radiation, ”says O’Connor.

They discovered the Falcatakely may have looked similar to modern birds due to convergent evolution, which occurs when unrelated animals evolve similarly and share the same traits. But unlike modern birds, the Falcatakely obtains its broad beak by enlarging the jawbone, another bone in the skull.

“The point of convergence is that it has this general general shape, but it doesn’t do it by modifying the same facial bones that we see in modern birds,” says O’Connor. On the contrary, the beak of this bird is closer to the structure of one of the most ferocious dinosaurs – velociraptors.

“It uses what we’ve described as a sort of primitive arrangement of bone structure that looks more like things like the velociraptor or the microraptor.”

A new path – The discoveries chart a new course in the fossil record and overturn scientists’ beliefs about what ancient birds might look like.

“We never would have predicted that something like that would have, you know, a really big, big beak, and that it would be based on the jawbone, because we’ve never seen that in the fossil record before,” said O’Connor

But, more importantly, the study reshapes our understanding of ancient birds and their evolution.

“The birds living in the Mesozoic were much more diverse than anything we’ve ever known,” says O’Connor.

Abstract: Mesozoic birds exhibit considerable diversity in size, flight adaptations, and feather organization1–4, but exhibit relatively conserved patterns of beak shape and development5–7. Although neornithine birds (i.e., the crown group) also exhibit constraints on facial development8,9, they have relatively diverse beak morphologies associated with a range of foraging ecologies. and behavior, unlike Mesozoic birds. Here we describe a bird with a crow-sized stem, Falcatakely forsterae gen. and sp. nov., from the Late Cretaceous period of Madagascar which possesses a long and deep rostrum, an expression of beak morphology that was previously unknown in Mesozoic birds and which is superficially similar to that of a variety of birds of the crown group (for example, toucans). Falcatakely’s rostrum is composed of an expansive edentulous maxilla and a small premaxilla with teeth. Morphometric analyzes of individual bony elements and the three-dimensional shape of the rostrum reveal the development of a neornithine-like facial anatomy despite maintaining a maxillary-premaxillary organization similar to that of non-avian theropods. The structure and increase in rostral height in Falcatakely reveals a degree of developmental lability and an increase in morphological disparity that was previously unknown in early branching avialans. The expression of this phenotype (and presumed ecology) in a stem bird emphasizes that union at the neornithine-like premaxillary rostrum was not an evolutionary prerequisite for beak enlargement.