Home / Science / The first dinosaur feather ever found is still controversial

The first dinosaur feather ever found is still controversial

The famous fossil feather.

The famous fossil feather.
Image: Museum für Naturkunde

A fossilized feather found 159 years ago in Germany is back in the paleontological spotlight, with new research claiming that the feather is from a similar bird Archeopteryx, much to the chagrin of dissenting scientists.

When it is discovered out of context, a feather fossil presents a severe headache for paleontologists. This is the case for a 150 million year old feather found in a German limestone quarry in 1861. Without a frame of reference, scientists were unable to tell which species this fossil, the first dinosaur feather ever discovered, belonged to, or what part of the body it came from.

With the discovery of a Archeopteryx fossil a few years later, scientists naturally linked the two together. This connection was not entirely outrageous, as modern scientists have discovered other reasons to connect the iconic bird-like dinosaur to the isolated feather. Dating back to the Jurassic, Archeopteryx it represents an extremely important species, as it has shown an important evolutionary link between dinosaurs and birds.

Artistic impression of an Archeopteryx skeleton, including a falling primary hidden feather.

Artistic impression of a Archeopteryx skeleton, including a falling primary hidden feather.
Image: Ryan Carney

Last year a Research the paper written in collaboration with paleontologist Michael Pittman of the University of Hong Kong has cast a serious shadow on this assumption, concluding that the isolated feather belongs to some “unknown feathered dinosaur.”And certainly not Archeopteryx.

Not so fast, says an international team of scientists led by the University of South Florida. Their new article, published today in Scientific Reports, claims that the feather indeed belongs to Archeopteryx, as previously assumed. The new study was suggested by the claims made in the Pittman paper and others recent documents wrote on the subject, as Ryan Carney, the first author of the new paper and USF biologist, explained in an email.

“We wanted to formally address the errors and set the record straight (fossils), so to speak,” Carney wrote. “Also, I was a big fan of high school debates, so I like that kind of thing. “

Carney and his colleagues analyzed nine different aspects of the fossilized feather, with a focus on the long quill. These details they were then compared with similar anatomical features seen in modern birds. The team also studied the skeletal fossils of Archeopteryx, of which 13 are known to exist. The researchers looked at “every feather in every Archeopteryx fossil, every single isolated feather tip and every relevant piece of feather literature from the 1800s to the present, ”Carney said.

A central component of the new document is an anatomical feature known as the primary secret. In birds, primary coverts are the shortest group of feathers strung near the top edge of a wing, overlapping the longer primary feathers used for flight and gliding. The isolated feather fossil appears to be a primary secretone that is identical in size and shape to those seen on the upper surface of the Archeopteryx wing, according to research. As further evidence, notes the team that the fossil feather was found near the same site in Germany that produced four Archeopteryx skeletons.

Based on the available evidence, “the most empirical and parsimonious conclusion is that this feather represents a primary cover from the ancient wing of Archeopteryx,”The authors wrote in their study.

In terms of other interesting findings, the researchers I believe the feather came from the animal’s left wing and an analysis of the preserved melanosomes – micro-scale pigment structures –suggests that the whole feather was dull black, which contradicts claim of previous research Archeopteryx the feathers were slightly modeled.

The 1862 drawing of the fossil feather. showing an alleged pen.

The 1862 drawing of the fossil feather. showing an alleged pen.
Image: T. G. Kaye et al., 2019

It is important to note that Carney’s team did not actually analyze the fossil same, but rather a high resolution digital scan of a drawing made of the fossil. German paleontologist Hermann von Meyer created the life-size trace of the fossil in 1862 using a drawing mirror. Digital scanning allowed for “more accurate and precise measurements,” the authors wrote.

In contrast, Pittman’s team, which included Thomas Kaye of the Arizona Foundation for Scientific Advancement, used a technique called laser-stimulated fluorescence (LSF) to create a chemical ‘halo’ of the feather, allowing the team to see features on the fossil that would otherwise be invisible. A comparative analysis of all known feather preservatives Archeopteryx Samples were also run. Scientists had previously identified the feather as a file Archeopteryx primary secret, but Pittman and his team of colleagues felt their data ruled it out as a possibility.

The feather seen with laser-stimulated fluorescence.

The feather seen with laser-stimulated fluorescence.
Image: T. G. Kaye et al., 2019

When asked to comment on the new article, Pittman said his team “never even considered using a drawing, as the LSF image and fossil show us the primary data,” adding that the resulting data discrepancies observed in the two documents “result from the use of two different data sources.” For example, Pittman indicated a perfectly centered line on the 1862 drawing, which does not appear centered on the LSF image. It may not seem like much, but even the smallest feature can affect how other parts of the feather are interpreted, He said. Pittman believes that “science would have been better served” if Carney and his colleagues “had used all available data and created error bars” to account for the most likely positions of certain characteristics.

Carney, on the other hand, believes this debate has finally been resolved.

“Given the isolated nature of the feather, we can never have 100% absolute certainty,” he said, but “the mountain of evidence speaks for itself.” Furthermore, there are “no other known feathered dinosaurs at that time and place that have anything close to the advanced flight feather stage represented by this isolated feather,” he added.

Right, but Pittman’s concerns are not without guarantees. T.he source of this feather is clearly still controversial, so hopefully future research will to resolve this debate in one way or another.

It may seem superfluous to spend so much time and energy on a single feather, but as Carney pointed out, no known feathered dinosaurs except Archeopteryx can currently explain this fossil. And if Pittman is right – that he belongs to an unknown species – it means that there are some important fossils out there still waiting to be discovered.

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