Archaeopteryx feather not Archaeopteryx feather


This 2016 video says about itself:

Archeopteryx had strong feathers, bony jaws and teeth, and a tail with a line of bone running down its legs. Physically, it was exactly half-reptile, half-bird.

From The University of Hong Kong:

First discovered fossil feather did not belong to iconic bird Archaeopteryx

Imaging technology shows first discovered fossil feather did not belong to iconic bird Archaeopteryx

February 4, 2019

A 150-year-old fossil feather mystery has been solved by an international research team including Dr Michael Pittman from the Department of Earth Sciences, The University of Hong Kong. Dr Pittman and his colleagues applied a novel imaging technique, Laser-Stimulated Fluorescence (LSF), revealing the missing quill of the first fossil feather ever discovered, dethroning an icon in the process.

This fossil feather was found in the Solnhofen area of southern Germany in 1861. The isolated feather was used to name the iconic fossil bird Archaeopteryx and was closely identified with its skeletons. Unlike the feather impressions preserved in some Archaeopteryx fossils, the isolated feather is preserved as a dark film. The detailed 1862 description of the feather mentions a rather long quill visible on the fossil, but this is unseen today. Even recent x-ray fluorescence and UV imaging studies did not end the debate of the “missing quill.” The original existence of this quill has therefore been debated and it was unclear if the single feather represented a primary, secondary, or primary covert feather.

The results of this study are described in the journal Scientific Reports, and underscore the potential and scientific importance of Laser-Stimulated Fluorescence, which is being developed by Thomas G Kaye of the Foundation for Scientific Advancement, USA and Dr Pittman. “My imaging work with Tom Kaye demonstrates that important discoveries remain to be made even in the most iconic and well-studied fossils,” says Dr Pittman.

With the help of the LSF images, the team finally solved the 150-year-old missing quill mystery. The now completely visible feather allowed detailed comparisons with the feather impressions of Archaeopteryx and with living birds. Before this LSF work, the feather was thought to represent a primary covert from Archaeopteryx, but this study shows that it differs from coverts of modern birds by lacking a distinct s-shaped centerline. The team also ruled out that the feather represented a primary, secondary, or tail feather of Archaeopteryx. Instead, the new data indicates that the isolated feather came from an unknown feathered dinosaur and that its attribution to Archaeopteryx was wrong. “It is amazing that this new technique allows us to resolve the 150-year-old mystery of the missing quill,” says Daniela Schwarz, co-author in the study and curator for the fossil reptiles and bird collection of the Museum für Naturkunde, Berlin. This discovery also demonstrates that the diversity of feathered dinosaurs was likely higher around the ancient Solnhofen Archipelago than previously thought. “The success of the LSF technique here is sure to lead to more discoveries and applications in other fields. But, you’ll have to wait and see what we find next!” added Tom Kaye, the study’s lead author.

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How sauropod dinosaurs moved, new study


This video is called Sauropod OviparityWalking With Dinosaurs – BBC.

From the University of Bonn in Germany:

Long-necked dinosaurs rotated their forefeet to the side

Scientists investigated the tracks of sauropods

January 29, 2019

Long-necked dinosaurs (sauropods) could orient their forefeet both forward and sideways. The orientation of their feet depended on the speed and centre of mass of the animals. An international team of researchers investigated numerous dinosaur footprints in Morocco at the foot of the Atlas Mountains using state-of-the-art methods. By comparing them with other sauropod tracks, the scientists determined how the long-necked animals moved forward. The results have now been published in the Journal of Vertebrate Paleontology.

“Long-necked dinosaurs” (sauropods) were among the most successful herbivores of the Mesozoic Era — the age of the dinosaurs. Characteristic for this group were a barrel-shaped body on columnar legs as well as an extremely long neck, which ended in a relatively small head. Long-necked dinosaurs existed from about 210 to 66 million years ago — they thus had been able to assert themselves on earth for a very long period. Also their gigantism, with which they far surpassed other dinosaurs, points at their success.

Sauropods included the largest land animals in Earth history, some over 30 metres long and up to 70 tonnes in weight. “However, it is still unclear how exactly these giants moved,” says Jens Lallensack, paleontologist at the Institute of Geosciences and Meteorology at the University of Bonn in Germany. The limb joints were partly cartilaginous and therefore not fossilised, allowing only limited conclusions about the range of movement.

Detective work with 3D computer analyses

The missing pieces of the puzzle, however, can be reconstructed with the help of fossil footprints of the giants. An international team of researchers from Japan, Morocco and Germany, led by the University of Bonn, has now investigated an unique track site in Morocco at the foot of the Atlas Mountains. The site consists of a surface of 54 x 6 metres which was vertically positioned during mountain formation and shows hundreds of individual footprints, some of which overlap. A part of these footprints could be assigned to a total of nine trackways (sequences of individual footprints). “Working out individual tracks from this jumbled mess of footprints was detective work and only possible through the analysis of high-resolution 3D models on the computer,” says Dr. Oliver Wings of the Zentralmagazin Naturwissenschaftlicher Sammlungen der Martin-Luther-Universität Halle-Wittenberg in Germany.

The researchers were amazed by the results: the trackways are extremely narrow — the right and left footprints are almost in line. Also, the forefoot impressions are not directed forwards, as is typical for sauropod tracks, but point to the side, and sometimes even obliquely backwards. Even more: The animals were able to switch between both orientations as needed. “People are able to turn their palms downwards by crossing the ulna and radius,” says Dr. Michael Buchwitz of the Museum für Naturkunde Magdeburg. However, this complicated movement is limited to mammals and chameleons in today’s terrestrial vertebrates. It was not possible in other animals, including dinosaurs. Sauropods must therefore have found another way of turning the forefoot forwards.

How can the rotation of the forefoot be explained?

How can the rotation of the forefoot in the sauropod tracks be explained? The key probably lies in the mighty cartilage layers, which allowed great flexibility in the joints, especially in the shoulder. But why were the hands rotated outwards at all? “Outwardly facing hands with opposing palms were the original condition in the bipedal ancestors of the sauropods,” explains Shinobu Ishigaki of the Okayama University of Science, Japan. The question should therefore be why most sauropods turned their forefeet forwards — an anatomically difficult movement to implement.

A statistical analysis of sauropod tracks from all over the world could provide important clues: Apparently the animals tended to have outwardly directed forefeet when the foreleg was not used for active locomotion but only for carrying body weight. Thus the forefeet were often rotated further outwards when the animal moved slowly and the centre of mass of the body was far back. Only if the hands were also used for the forward drive, a forefoot directed to the front was advantageous. The analysis furthermore showed that the outer rotation of the forefeet was limited to smaller individuals, whereas in larger animals they were mostly directed forward. The large animals apparently could no longer rotate their forefeet sideways. “This loss of mobility was probably a direct result of their gigantism,” says Lallensack.

English Jurassic ichthyosaur, new study


This 8 January 2019 video from England says about itself:

Medical scanner helps to unlock the mysteries of a giant ichthyosaur skull

This is the skull and postcranial skeleton of the Early Jurassic (~200 million year old) ichthyosaur, Protoichthyosaurus prostaxalis. It was collected in 1955 at Fell Mill Farm near Shipston-on-Stour, Warwickshire.

I first began to study this specimen in late 2014, and after more than four years, the research has finally been published.

Working together with Dr Laura Porro and Nigel Larkin, we have thoroughly described this incredible specimen, which has never formally been described. Each individual bone of the skull and skeleton has been examined in great detail and described.

From the University of Manchester in England:

Medical scanner helps to unlock the mysteries of a giant prehistoric marine reptile

January 8, 2019

A nearly metre-long skull of a giant fossil marine ichthyosaur found in a farmer’s field more than 60 years ago has been studied for the first time.

Using cutting-edge computerised tomography (CT) scanning technology, the research reveals new information including details of the rarely preserved braincase.

The almost 200 million year old fossil, which was found in 1955 at Fell Mill Farm in Warwickshire, had never formally been studied prior to this research.

Now, thanks to data collected from CT scans, the research team were able to digitally reconstruct the entire skull in 3D. It is the first time a digital reconstruction of a skull and mandible of a large marine reptile has ever been made available for research purposes and to the public.

Although thousands of ichthyosaur fossils have been unearthed in the UK, this specimen is particularly important and unusual because it is three-dimensionally preserved and contains bones of the skull that are rarely exposed.

In 2014, as part of a project at Thinktank Science Museum, Birmingham, palaeontologists Dean Lomax, from The University of Manchester, and Nigel Larkin began to study the skull and its incomplete skeleton for the first time and were soon convinced of its importance.

Dean, the lead author and one of the world’s leading ichthyosaur experts, explains: “The first time I saw this specimen I was puzzled by its excellent preservation.

Ichthyosaurs of this age (Early Jurassic) are usually ‘pancaked’, meaning that they are squished so that the original structure of the skull is either not preserved or is distorted or damaged. So to have a skull and portions of the skeleton of an ichthyosaur of this age preserved in three dimensions, and without any surrounding rock obscuring it, is something quite special.”

The ichthyosaur was originally identified as a common species called Ichthyosaurus communis, but after studying it closer, Dean was convinced it was a rarer species. Based on various features of the skull, he identified it as an example of an ichthyosaur called Protoichthyosaurus prostaxalis. With a skull almost twice as long as any other specimen of Protoichthyosaurus, this is the largest specimen so far known of the species.

Co-author Nigel Larkin added: “Initially, the aim of the project was to clean and conserve the skull and partially dismantle it to rebuild it more accurately, ready for redisplay at the Thinktank Museum. But we soon realised that the individual bones of the skull were exceptionally well preserved in three dimensions, better than in any other ichthyosaur skull we’d seen. Furthermore, that they would respond well to CT scanning, enabling us to capture their shape digitally and to see their internal details. This presented an opportunity that couldn’t be missed”

The skull isn’t quite complete, but several bones of the braincase — which are rarely preserved in ichthyosaurs — are present. To unlock information contained in the skull, these bones were micro-CT scanned at Cambridge University in 2015 by expert palaeontologist and co-author, Dr Laura Porro of University College London (UCL).

The fossil only preserved bones from the left side of the braincase; however, using CT scans these elements were digitally mirrored and 3D printed at life size to complete the braincase. Finally, the entire skull was CT scanned at the Royal Veterinary College (RVC) using a scanner typically reserved for horses and other large animals.

Dr Porro added: “CT scanning allows us to look inside fossils — in this case, we could see long canals within the skull bones that originally contained blood vessels and nerves. Scans also revealed the curation history of the specimen since its discovery in the ’50s. There were several areas reconstructed in plaster and clay, and one bone was so expertly modelled that only the scans revealed part of it was a fake. Finally there is the potential to digitally reconstruct the skull in 3D. This is hard (and risky) to do with the original, fragile and very heavy fossil bones; plus, we can now make the 3D reconstruction freely available to other scientists and for education.”

The use of modern technologies, such as medical scanners, have revolutionised the way in which palaeontologists are able to study and describe fossils.

Dean added: “It’s taken more than half a century for this ichthyosaur to be studied and described, but it has been worth the wait. Not only has our study revealed exciting information about the internal anatomy of the skull of this animal, but our findings will aid other palaeontologists in exploring its evolutionary relationship with other ichthyosaurs.”

Pterosaurs, new discovery


This 6 December 2018 video says about itself:

Devil of the Jurassic

Pterosaurs came in all sorts of shapes and sizes during their time on Earth, and one of the most important pterosaur discoveries was the uncovering of this species – Sordes pilosus.

Liopleurodon, big Jurassic plesiosaurs


This 7 January 2019 video says about itself:

Liopleurodon (meaning ‘smooth-sided teeth’) is a genus of large, carnivorous marine reptile belonging to the Pliosauroidea, a clade of short-necked plesiosaurs. The two species of Liopleurodon lived during the Callovian stage of the Middle Jurassic Period (c. 160 to 155 mya).

Liopleurodon … was the apex predator of the Middle to Late Jurassic seas that covered Europe.

The largest species, L. ferox, is estimated to have grown up to 6.4 metres (21 ft) in length. Liopleurodon fossils have been found mainly in England and France. Fossil specimens that are contemporary (Callovian) with those from England and France referable to Liopleurodon are known from Germany. Currently, there are two recognized species within Liopleurodon. Only L. ferox is known from more or less complete skeletons.

Big Jurassic carnivorous dinosaur discovery


This 19 December 2018 video is about the discovery of the oldest ceratosaurian dinosaur in the Italian Alps.

From PeerJ:

The oldest large-sized predatory dinosaur comes from the Italian Alps

December 19, 2018

Early Jurassic predatory dinosaurs are very rare, and mostly small in size. Saltriovenator zanellai, a new genus and species described in the peer-reviewed journal PeerJ — the Journal of Life and Environmental Sciences by Italian paleontologists, is the oldest known ceratosaurian, and the world’s largest (one ton) predatory dinosaur from the Lower Jurassic (Sinemurian, ~198 Mya).

This unique specimen, which also represents the first Jurassic dinosaur from Italy, was accidentally discovered in 1996 by a fossil amateur within a quarry near Saltrio, some 80 km N-E of Milan. Many bones of Saltriovenator bear feeding marks by marine invertebrates, which represent the first case on dinosaurian remains and indicate that the dinosaur carcass floated in a marine basin and then sunk, remaining on the sea bottom for quite a long time before burial.

Although fragmentary, “Saltriovenator shows a mosaic of ancestral and advanced anatomical features, respectively seen in the four-fingered dilophosaurids and ceratosaurians, and the three-fingered tetanuran theropods, such as allosaurids,” says first author Cristiano Dal Sasso, of the Natural History Museum of Milan, who reassembled and studied the fossil for several years.

“Paleohistological analysis indicates that Saltriovenator was a still growing subadult individual, therefore its estimated size is all the more remarkable, in the context of the Early Jurassic period,” says co-author Simone Maganuco.

“The evolutionary ‘arms race’ between stockier predatory and giant herbivorous dinosaurs, involving progressively larger species, had already begun 200 million of years ago.”

The evolution of the hand of birds from their dinosaurian ancestors is still hotly debated. “The grasping hand of Saltriovenator fills a key gap in the theropod evolutionary tree: predatory dinosaurs progressively lost the pinky and ring fingers, and acquired the three-fingered hand which is the precursor of the avian wing,” remarks co-author Andrea Cau.