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Wings Archeopteryx It is one of the best-known dinosaurs in science, but its place in the genealogical tree of evolution has not been discussed. The reported discovery of a brand new species of Archeopteryx with distinctive bird features suggests that its relationship with modern birds is more meaningful than we thought. Critics, on the other hand, say that it is premature to designate the fossil specimen as belonging to a new species.
This is called Archeopteryx albersdoerferi – a Jurassic dinosaur that looks less like a reptile and a bird than any other known Archeopteryx species, according to new research published today in historical biology. If confirmed, it will only be the third kind of Archeopteryx identified among the 12 known fossilized skeletons (or 10, depending on who you ask for).
This fossil was discovered in 2009 (number eight), but a new analytical technique was used for the analysis. It is therefore the classic case of an old fossil seen under new eyes. That the authors of the new study declare the specimen as a separate species should not be a surprise.
Virtually all new fossils of Archeopteryx was first declared new species before being reintegrated into one of the two known species, either Archeopteryx lithography or Archeopteryx siemensii, after further examination. The same thing could happen to Archeopteryx albersdoerferiBut only time will tell.
Archeopteryx is one of the most intriguing dinosaurs in paleontological history. Discovered in the 1860s, this dinosaur of the Jurassic era was celebrated as a remarkable demonstration of evolution in action. Not quite lizard and not quite a bird, it seemed to show, almost literally, lizards evolving into birds. Archeopteryx was described as a "transitory" species – a so-called missing link between extinct dinosaurs and modern birds.
Over the years, however, paleontologists have struggled to place Archeopteryx in the family tree that leads to modern birds. The discovery of other creatures resembling birds of the era of dinosaurs, whose size and characteristics better match the appearance of modern birds, led some scientists to conclude that Archeopteryx was a stalemate of evolution, and that modern birds have a different common ancestor.
Archeopteryx has been dubbed "a non-avialan theropod-like bird converge," meaning a non-avian feathered dinosaur that has acquired the characteristics of a bird during the process of convergent evolution.
That's what makes this new analysis so potentially important. The lead author of the new study, Martin Kundrát of the Pavol Jozef Šafárik University in Slovakia, said the specimen was more like a modern bird than any other Archeopteryx specimen discovered to date. The new paper is so nudging Archeopteryx a step or two closer to the family tree that leads to modern birds.
This Archeopteryx fossil was fired from the Mörnsheim formation in Germany, and he is the youngest of all known Archeopteryx specimens about 500,000 years old, according to the study. All Archeopteryx The fossils date back to the Upper Jurassic, about 150 million years ago, at the time of the first bird-like dinosaurs.
It looks a lot like an older species called A. lithographica, say the researchers, but the age of the new fossil, associated with its unique physical features, distinguishes it as a distinct species from Archeopteryx.
To study the specimen, the Kundrát team used a scanning technique called synchrotron microtomography, which allows scientists to visualize specimens in three dimensions and observe the interior features without having to open them.
"By digitally dissecting the fossil, we found that this specimen was different from all the others," said John Nudds, co-author of the study and paleontologist at the University of Manchester, in a statement. "He had skeletal adaptations that would have allowed for a much more efficient flight." In a nutshell, we found out what A. lithographica evolved into – a more advanced bird, better suited to fly – and we have described this as a new species of Archeopteryx. "
The researchers documented several distinct skeletal features, such as the fusion of his cranial bones, unique elements of the wings and chest (chest) and a more solid arrangement of the bones of the hand. Importantly, none of these features are found in older versions. Archeopteryx The researchers noted that the specimens, which look more like reptiles.
"This is the first time that many bones and teeth have Archeopteryx have been examined in all aspects, including the exposure of their internal structure, "said Kundrát," The use of synchrotron microtomography was the only way to study the specimen because it is strongly tablet with many broken bones partially or totally hidden in limestone.
Winged Archeopteryx Dino could fly, but scientists do not know how
Because of its bird characteristics, Archeopteryx is one of the most intriguing dinosaurs in science. Since its discovery 150 years ago, paleontologists have wondered if the Upper Jurassic dinosaur could fly.
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Troublingly, the researchers claim that their new study offers "the first synchrotron microtomographic examination of [Archaeopteryx] Genus ", which is categorically wrong: At the beginning of this year, a research team from the European Synchrotron Radiation Facility in Grenoble, France, and the University of Palacký in the Czech Republic, used a synchotron to study the flight potential of Archeopteryx. The fact that Kundrát and Nudds failed to report on this closely related research published in Nature Communications is a flagrant omission.
Dennis Voeten, lead author of Nature Communications, said the new study was "a welcome contribution to our understanding of variability Archeopteryx exhibits in the genre ", but he is not convinced that the fossil represents a new species.
"Almost all specimens were included in their own species at one time, and subsequent revisions remained unable to separate these animals into a limited number of" natural ", well-defined species," Voeten told Gizmodo.
The growth rate and the physical variability of Archeopteryx "Remains difficult to reconstruct," he said, and several key features, such as bone size and subtle physical traits, could be the result of individual variations or even bone deformities after the death of the animal, rather than signs of a separate species.
"Nevertheless, this new article provides a second powerful example of the value of synchrotron tomography for the reliable visualization of inestimable and fragile fossil internal structures," he said. "Future assessments of the beautiful fossils of Archeopteryx will undoubtedly reveal what morphological characters are associated with its true specific diversity and result from other factors at play. "
Finally, the first image used in this post – a reconstruction of the artist by A. albersdoerferi – takes serious liberties. Although Archeopteryx has physical characteristics compatible with the flight, it has not yet been proved that it was a free flight. As I wrote earlier this year, "scientists do not know if this animal used its wings for passive gliding or active powered flight.
Another possibility is that Archeopteryx was a terrestrial animal that did not fly at all, using its wings for something else, such as catching prey, jumping or doing sexual demonstrations. "
That being said, the recent work of Voeten and Kundrát is in line with Archeopteryx to be a flying creature, but its exact flight mode remains a mystery.
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