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Home / Science / How we discovered a new kind of "missing link" between dinosaurs and birds

How we discovered a new kind of "missing link" between dinosaurs and birds



One of the most famous fossils in the world is Archeopteryx . With its beautifully preserved feathers, it has long been considered the first bird in the fossil record and is often referred to as the "icon of evolution". Only a handful of specimens have ever been found, his elusivity adds to his fascination.

But was it really the first bird – and could it really fly? Now that we know of dinosaur-derived birds, was Archeopteryx just another small dinosaur with a feathery shell?

My colleagues and I had the rare opportunity to study a Archeopteryx skeleton with one of the world's most powerful synchrotrons, a type of particle accelerator similar to an X-ray machine, but ten thousand billion times brighter than a hospital. We could see inside the rock and expose bone fragments that had never been seen before. What we discovered surprised us: this was a completely new breed of Archeopteryx .

The first Archeopteryx fossil was found in the Jurassic limestones of Bavaria in the summer of 1

861, just two years after the publication of Darwin's Origin of Species. It seemed to be one of Darwin's predicted "missing connections," the connection between reptiles and birds, especially between dinosaurs and birds.

It certainly looked like a bird, with delicately preserved feathers on its wings and a fan-shaped tail. It also had a wishbone or "Furcula", just like you would find in a roast chicken. And these two properties were then only suspected in birds. But Archeopteryx also had some very reptile-like features – a long, bony tail and a jaw filled with very sharp teeth – and seemed to lie between the two groups of animals.

The eighth copy "
John Nudds Author provided

A second copy was found in 1876, but Archeopteryx Fossils are generally elusive and we only have 12 copies found. One of them has been lost and some others are fragments.

Despite more than 150 years of study, we still have much to discover about this primitive bird. Much of the controversy concerns the question of whether Archeopteryx could fly, with the consensus that it was at best a "weak flapper".

The eighth specimen to be discovered was one of the least known. It was found in the early 1990s by a private collector in a quarry near Daiting in Bavaria, and changed ownership several times before it was cheaply sold to another private collector, believing that it was an ordinary pterosaur , It is rumored that the finder, when he realizes what he has done, plunges from the top of the quarry, as these specimens can change for millions of dollars.

The new owner, perhaps feeling guilty, was very secretive about his. English: bio-pro.de/en/region/ulm/magazin/05202/index.html Until 1996, the science of this specimen was no longer known (hence the nickname "the phantom") was shown as a cast sample in the Natural History Museum in Bamberg. In 2009, the dinosaur hunter Raimund Albersdörfer, also from Bavaria, acquired the specimen and in 2011 made it available to our research team for scientific studies.

John Nudds with the fossil.
John Nudds author provided

It is not well preserved and we called it "the ugly bird" because the bones had been separated after it died and were scrambled and crushed. The lower half of the body was missing completely. But we brought it to Grenoble, to the European Synchrotron Radiation Source (ESRF), where we could perform a virtual skeletal dissection and put together pieces of bone that were broken when the animal died 150 million years ago [196592002] All copies of Archeopteryx was classified as a species, Archeopteryx lithographica but this one seemed to be different. It was also collected from a different layer in the Rock Plate than the others, all of which came from the well-known Solnhofen Formation. Our specimen was obtained from the Moernsheim Formation, which lies above the Solnhofen Formation and is about half a million years younger.

Closer to Birds

First, we discovered that the skull bones were fused together. Then we found that the furcula had a button-like extension, which in modern birds is an attachment to the mighty flight muscles. None of these features were seen in Archeopteryx lithographica . An extensive opening in one of the bones of the shoulder girdle (called the coracoid) suggested that a large nerve was penetrating this bone, suggesting a stronger wing beat.

But our biggest surprise was when we noticed the bones of the wrist were fused together – another feature of modern birds known as "Carpo-Metacarpus". This provided a rigid structure that would have allowed the wings a strong downward stroke.

A synchrotron scan helped reveal the features of the fossil.
Paul Tafforeau / ESRF Author provided

Archeopteryx lithographica instead had the flexible wrist seen in its dinosaur ancestors. It was evident that our specimen displayed many of the features found in modern flight birds not seen in the "fluttering" Archeopteryx lithographica . We had discovered a new kind of science, and we named it Archeopteryx albersdoerferi after its owner, who had rescued her from the darkness.

Whenever a missing link is discovered, only two more missing links are created: what? came before, and what came afterwards. In this case, the Archeopteryx was discovered in 1996 with the description of feathered dinosaurs in China. Our new species is what came afterwards. It confirms Archeopteryx as the first bird and not only as one of several feathered theropod dinosaurs, as some researchers have recently suggested. Our research put Archeopteryx back in position as the first bird.


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