Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Stunning fossil discovery reveals the second most primitive flying bird

Stunning fossil discovery reveals the second most primitive flying bird

Paleontologists in Japan have discovered the fossil remains of a 120-million-year-old flying dinosaur that seriously shakes the birds' pedigree.

Many of you may have heard of Archeopteryx —a winged, long-tailed dinosaur that lived during the Late Jurassic period about 160 million to 140 million years ago. This creature, with its flight and tail feathers, is the earliest known flying dinosaur and a critically important species to broaden our understanding of bird origin and flight evolution.

A new study published today in Communications Biology now describes the second most primitive or major flying dinosaur in the evolutionary record, an entirely new genus and species known as Fukuipteryx prima . The newly described species replaces Jeholornis which is currently the third most primitive bird.

Discovered in Japan, this dinosaur lived 1

20 million years ago during the Early Cretaceous period (145 million to 100 million years ago), but the authors of the new study, led by paleontologist Takuya Imai of the Dinosaur Research Institute in Fukui Prefectural University of Japan, have good reason to believe that this species appeared before that time.

The image of Fukuipteryx's artist prima.
Image : Masanori Yoshida

Archeopteryx is still the king of basal birds, but very important physical characteristics associated with modern birds do not appear until early Cretaceous. The most notable of these features is the pygostyle, a triangular plate located at the tip of the spine that modern birds use to support flying feathers. As the new book reveals, Fukuipteryx is an early Pygostyle bird capable of limited flight, but its dangerous end may not have contributed to this capacity. Fukuipterix was discovered in the career of the dinosaurs of Kitadani near Katsuyama City in Fukui Prefecture, Japan, and is the first bird of this crucial period to be discovered outside northeastern China. The fossil, a three-dimensional preserved specimen, was almost completely raised – the size of a dove – when it died. 3D preservation is a rarity, since most other bird fossils of this period have been cut into flat slabs, creating two-dimensional impressions. Therefore, fossil Fukuipteryx was able to provide more anatomical information than usual.

One observation came as a big surprise to the researchers. Although the species is the most anatomically primitive bird of the Early Cretaceous, it is found in relatively young sediment, and more evolutionarily advanced species are found in a sediment older than the fossil Fukuipteryx .

"We were so surprised that we did the whole analysis again because we decided we had done something wrong," Ezima told Gizmodo in an email. But it turned out the same no matter how many times we checked our data and methods – the result did not change. "

Left: Fukuipteryx fossil receives. Right: Illustration of the bones contained inside.
Image : T. Imai et al., 2019

In order to carry out the analysis, Imai and his colleagues carefully measure the specimen and perform a comparative physical analysis with other fossil birds. Paleontologists could not remove the fossil bones from the rock for fear of damaging the specimen, so they used a micro-CT scan technique to observe the skeleton embedded in the rock in a procedure similar to how medical X-rays work, but with microscopic accuracy and the ability to smooth data in a digital 3D model.

Physical analysis reveals some similarities with Archeopteryx such as a large iron bone, a molten pelvis, and similar forelimbs.

" Fukuipteryx shows some unexpected combination of adaptations when viewed in the context of the early dinosaur flight," says Dennis Wojten, a paleontologist at Palacký University in the Czech Republic who did not participate in the study. in an email to Gizmodo. "Some of the bones of the shoulders and wings that would play an important role in air travel look quite primitive and largely resemble those of the oldest flying dinosaur discovered so far – Archeopteryx ."

However, unlike Archeopteryx however, Fukuipteryx had a fully formed pygostyle. The important thing is that the imam and his team do not believe that pygostyle is related to the fields and is instead a by-product of shrinking tails among these dinosaurs during evolutionary time. The authors believe that Fukuipteryx may fly, but is not as experienced as modern birds, and is likely to glide or swing at short distances.

Despite their much more modern tail shape, researchers have positioned Fukuipterix "as the second most primitive flying dinosaur, only after Archaeopteryx " because of the very primitive bones of the ramen said Wighton.

The discovery of the pygostyle of Fukuipteryx is not as big a deal as it may sound in terms of its evolutionary role in bird flight, but it is a big deal as to where it places birds in the pedigree phylogenetic tree .

"A couple of theropod dinosaurs [ten-bird-dinosaurslike T. Rex and predatory birds] that apparently didn't fly, apparently had a pygostyle," Imam said. "Studies by Fukuipteryx show that pygostyle evolved at least twice during the evolution of birds, once in the pedigree of Fukuipteryx and once in the pedigree of modern birds. The observation that the long tail of Jeholornis is phylogenetically more advanced than the short-tailed Fukuipteryx together with the presence of pygostyle in non-avian theropods, suggests that pygostyle is not obligatory [9]a paleontologist at the Vertebrate Paleontology Laboratory at the University of Hong Kong added a little color to these details.

"The earliest diverging fossil birds had long tails and are known from late Jurassic rocks from southern Germany and early Cretaceous rocks from northeastern China. What makes Fukuipteryx special is that its tail is short instead, and ends in a condensed peak called a pygostyle, ”explained Pitman, who did not participate in the new research, in an email to Gizmodo. "This is surprising because this type of tail was previously known only in later-breeding fossil birds such as Jinguofortis Confuciusornis and Sapeornis and is what we now see in [19659003] Pitman said the discovery was important in that it extended the fossil record from the earliest birds to the early Cretaceous of Japan.

Wighton says researchers have provided "a detailed review of Fukuipterix that will certainly help reconstruct the wider context of early dinosaur flight," but he pointed out an important limitation.

"Although quite a number of his bones have been found, the highly informative skull is unfortunately too damaged to be included in the description," Witton told Gizmodo. "As many informative adaptations have been identified in the skull, only time will tell whether Fukuipterix really maintains its primitive position among the pioneers of dinosaur flight. However, this is not something the authors could prevent. Fossilization is a rare process and since the bones of flying animals tend to be fragile, they are often damaged upon detection. "

In conceptual terms, Wighton says that the term" primitive "does not always accurately reflect the passage of time. He explained:

In fact, Fukuipteryx and Jeholornis share the sky with a wide variety of modern dinosaurs, similar to birds, which probably already enjoy much more advanced flying capabilities. Fuquipterix lived about 35 million years after Archaeopteryx and therefore may not retain the exact adaptations that allowed the first flying dinosaurs to ascend into the sky after all. Nevertheless, it fits well into a theory that has been gaining traction over the last few years.

When traditionally the evolution of a dinosaur flight was seen as beginning in a species that gives birth to all other feathered leaflets, including modern birds, we now begin to see that the Mesozoic period may have been the stage of many diverse dinosaur flight experiments that not necessarily limited to one line. Because comparable habits can lead to many similar skeletal adaptations, reconstructing the family relationships of a diverse group of extinct flying dinosaurs may prove much more difficult than is currently thought. Because modern birds with highly advanced flight adaptations are the only dinosaurs that survived the catastrophic impact of the meteorite at the end of the Cretaceous, no directly comparable primitive birds can be observed today. This makes the interpretation of the bizarre experiments on flights during the Mesozoic not only very challenging but also very important for the harvesting of the lost diversity of dinosaurs.

Funny how science works. The beginning of a field can lead to overly simplistic theories, but they often appear only this way. Truth is almost always more complex, as we learn, for example, with human evolution . The more we learn about the past, the more complex it seems. But what seems impossible now cannot always be so. We just have to keep digging, literally and figuratively, for more evidence.

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