Dinosaur age bird could already fly well


Holotype of Junornis houi. (From Liu et. al; 2017)

From PLOS ONE:

Flight aerodynamics in enantiornithines: Information from a new Chinese Early Cretaceous bird

Di Liu, Luis M. Chiappe, Francisco Serrano, Michael Habib, Yuguang Zhang, Qinjing Meng

October 11, 2017

Abstract

We describe an exquisitely preserved new avian fossil (BMNHC-PH-919) from the Lower Cretaceous Yixian Formation of eastern Inner Mongolia, China.

Although morphologically similar to Cathayornithidae and other small-sized enantiornithines from China’s Jehol Biota, many morphological features indicate that it represents a new species, here named Junornis houi.

The new fossil displays most of its plumage including a pair of elongated, rachis-dominated tail feathers similarly present in a variety of other enantiornithines. BMNHC-PH-919 represents the first record of a Jehol enantiornithine from Inner Mongolia, thus extending the known distribution of these birds into the eastern portion of this region.

Furthermore, its well-preserved skeleton and wing outline provide insight into the aerodynamic performance of enantiornithines, suggesting that these birds had evolved bounding flight—a flight mode common to passeriforms and other small living birds—as early as 125 million years ago.

See also here.

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First Jurassic ichthyosaur discovery in India


This video about ichthyosaurs is called Sea Reptile Birth – Walking with Dinosaurs in HQ – BBC.

From PLOS ONE:

First Jurassic ichthyosaur fossil found in India

The fish-like reptile was over five-meter long, likely ate ammonites and other crunchy prey

October 25, 2017

A new near-complete fossilized skeleton is thought to represent the first Jurassic ichthyosaur found in India, according to a study published October 25, 2017 in the open-access journal PLOS ONE by Guntupalli Prasad from the University of Delhi, India, and colleagues.

Ichthyosaurs, literally ‘fish lizards’ in Greek, were large marine reptiles which lived alongside dinosaurs in the Mesozoic Era. While many ichthyosaur fossils have been found in North American and Europe, in the Southern Hemisphere, their fossil record has mostly been limited to South America and Australia.

Now, the authors of the present study report what they believe to be the first Jurassic ichthyosaur found in India, from the Kachchh area in Gujarat. The near-complete skeleton, nearly 5.5m long, is thought to belong to the Ophthalmosauridae family, which likely lived between around 165 and 90 million years ago. It was found among fossils of ammonites and squid-like belemnites, and its tooth wear patterns suggest it predated such hard, abrasive animals.

While the authors have not yet been able to pinpoint the ichthyosaur‘s species, they believe that a full identification could inform on possible ophthalmosaurid dispersal between India and South America. They hope that unearthing more Jurassic vertebrates in this region could provide further insights into the evolution of marine reptiles in this part of the globe.

Lead author Guntupalli Prasad notes: “This is a remarkable discovery not only because it is the first Jurassic ichthyosaur record from India, but also it throws light on the evolution and diversity of ichthyosaurs in the Indo-Madagascan region of the former Gondwanaland and India’s biological connectivity with other continents in the Jurassic.”

World’s oldest trees, new research


This video from the USA says about itself:

Devonian forest

4 November 2013

This scene is excerpted from the Colorado Geology: Devonian-Mississippian video (in progress). These trees are the Progymnosperm Archaeopteris, and the forest floor includes Racophyton. Major soils did not develop until the first trees evolved on land.

Animation by Joseph Rogers and Leo Ascarrunz. Special thanks to Ian Miller and James Hagedorn (DMNS) for their input.

Interactive Geology Project, University of Colorado-Boulder.

From Cardiff University in Wales:

Fossils from the world’s oldest trees reveal complex anatomy never seen before

Intricate web of woody strands inside 374-million-year-old tree trunks point to most complicated trees to have ever grown on Earth

The first trees to have ever grown on Earth were also the most complex, new research has revealed.

Fossils from a 374-million-year-old tree found in north-west China have revealed an interconnected web of woody strands within the trunk of the tree that is much more intricate than that of the trees we see around us today.

The strands, known as xylem, are responsible for conducting water from a tree’s roots to its branches and leaves. In the most familiar trees the xylem forms a single cylinder to which new growth is added in rings year by year just under the bark. In other trees, notably palms, xylem is formed in strands embedded in softer tissues throughout the trunk.

Writing in the journal Proceedings of the National Academy of Sciences, the scientists have shown that the earliest trees, belonging to a group known as the cladoxlopsids, had their xylem dispersed in strands in the outer 5 cm of the tree trunk only, whilst the middle of the trunk was completely hollow.

The narrow strands were arranged in an organised fashion and were interconnected to each other like a finely tuned network of water pipes.

The team, which includes researchers from Cardiff University, Nanjing Institute of Geology and Palaeontology, and State University of New York, also show that the development of these strands allowed the tree’s overall growth.

Rather than the tree laying down one growth ring under the bark every year, each of the hundreds of individual strands were growing their own rings, like a large collection of mini trees.

As the strands got bigger, and the volume of soft tissues between the strands increased, the diameter of the tree trunk expanded. The new discovery shows conclusively that the connections between each of the strands would split apart in a curiously controlled and self-repairing way to accommodate the growth.

At the very bottom of the tree there was also a peculiar mechanism at play — as the tree’s diameter expanded the woody strands rolled out from the side of the trunk at the base of the tree, forming the characteristic flat base and bulbous shape synonymous with the cladoxylopsids.

Co-author of the study Dr Chris Berry, from Cardiff University’s School of Earth and Ocean Sciences, said: “There is no other tree that I know of in the history of Earth that has ever done anything as complicated as this. The tree simultaneously ripped its skeleton apart and collapsed under its own weight while staying alive and growing upwards and outwards to become the dominant plant of its day.

“By studying these extremely rare fossils, we’ve gained an unprecedented insight into the anatomy of our earliest trees and the complex growth mechanisms that they employed.

“This raises a provoking question: why are the very oldest trees the most complicated?”

Dr Berry has been studying cladoxylopsids for nearly 30 years, uncovering fragmentary fossils from all over the world. He’s previously helped uncovered a previously mythical fossil forest in Gilboa, New York, where cladoxylopsid trees grew over 385 million years ago.

Yet Dr Berry was amazed when a colleague uncovered a massive, well-preserved fossil of a cladoxylopsid tree trunk in Xinjiang, north-west China.

“Previous examples of these trees have filled with sand when fossilised, offering only tantalising clues about their anatomy. The fossilised trunk obtained from Xinjiang was huge and perfectly preserved in glassy silica as a result of volcanic sediments, allowing us to observe every single cell of the plant,” Dr Berry continued.

The overall aim of Dr Berry’s research is to understand how much carbon these trees were capable of capturing from the atmosphere and how this effected Earth’s climate.

Tyrannosaur discovery in Utah, USA


This 2015 video from the USA says about itself:

“Teratophoneus” is a genus of carnivorous tyrannosaurid theropod dinosaur which lived during the late Cretaceous period in what is now Utah, USA. It is known from an incomplete skull and postcranial skeleton recovered from the Kaiparowits Formation. “Teratophoneus” was named by Thomas D. Carr, Thomas E. Williamson, Brooks B. Britt and Ken Stadtman in 2011 and the type species is “T. curriei”. The generic name is derived from Greek “teras”, “monster”, and “phoneus”, “murderer”. The specific name honors Philip J. Currie.

From the University of Utah in the USA:

New tyrannosaur fossil is most complete found in Southwestern US

Researchers are amazed to find nearly complete skeleton with many bones in life position

October 19, 2017

A remarkable new fossilized skeleton of a tyrannosaur discovered in the Bureau of Land Management’s Grand Staircase-Escalante National Monument (GSENM) in southern Utah was airlifted by helicopter Sunday, Oct 15, from a remote field site, and delivered to the Natural History Museum of Utah where it will be uncovered, prepared, and studied. The fossil is approximately 76 million years old and is most likely an individual of the species Teratophoneus curriei, one of Utah‘s ferocious tyrannosaurs that walked western North America between 66 and 90 million years ago during the Late Cretaceous Period.

“With at least 75 percent of its bones preserved, this is the most complete skeleton of a tyrannosaur ever discovered in the southwestern US,” said Dr. Randall Irmis, curator of paleontology at the Museum and associate professor in the Department of Geology and Geophysics at the University of Utah. “We are eager to get a closer look at this fossil to learn more about the southern tyrannosaur’s anatomy, biology, and evolution.”

GSENM Paleontologist Dr. Alan Titus discovered the fossil in July 2015 in the Kaiparowits Formation, part of the central plateau region of the monument. Particularly notable is that the fossil includes a nearly complete skull. Scientists hypothesize that this tyrannosaur was buried either in a river channel or by a flooding event on the floodplain, keeping the skeleton intact.

“The monument is a complex mix of topography — from high desert to badlands — and most of the surface area is exposed rock, making it rich grounds for new discoveries, said Titus. “And we’re not just finding dinosaurs, but also crocodiles, turtles, mammals, amphibians, fish, invertebrates, and plant fossils — remains of a unique ecosystem not found anywhere else in the world,” said Titus.

Although many tyrannosaur fossils have been found over the last one hundred years in the northern Great Plains region of the northern US and Canada, until relatively recently, little was known about them in the southern US. This discovery, and the resulting research, will continue to cement the monument as a key place for understanding the group’s southern history, which appears to have followed a different path than that of their northern counterparts.

This southern tyrannosaur fossil is thought to be a sub-adult individual, 12-15 years old, 17-20 feet long, and with a relatively short head, unlike the typically longer-snouted look of northern tyrannosaurs.

Collecting such fossils from the monument can be unusually challenging. “Many areas are so remote that often we need to have supplies dropped in and the crew hikes in,” said Irmis. For this particular field site, Museum and monument crews back-packed in, carrying all of the supplies they needed to excavate the fossil, such as plaster, water and tools to work at the site for several weeks. The crews conducted a three-week excavation in early May 2017, and continued work during the past two weeks until the specimen was ready to be airlifted out.

Irmis said with the help of dedicated volunteers, it took approximately 2,000-3,000 people hours to excavate the site and estimates at least 10,000 hours of work remain to prepare the specimen for research. “Without our volunteer team members, we wouldn’t be able to accomplish this work. We absolutely rely on them throughout the entire process,” said Irmis.

Irmis says that this new fossil find is extremely significant. Whether it is a new species or an individual of Teratophoneus, the new research will provide important context as to how this animal lived. “We’ll look at the size of this new fossil, it’s growth pattern, biology, reconstruct muscles to see how the animal moved, how fast could it run, and how it fed with its jaws. The possibilities are endless and exciting,” said Irmis.

During the past 20 years, crews from the Natural History Museum of Utah and GSENM have unearthed more than a dozen new species of dinosaurs in GSENM, with several additional species awaiting formal scientific description. Some of the finds include another tyrannosaur named Lythronax, and a variety of other, plant-eating, dinosaurs — among them duck-billed hadrosaurs, armored ankylosaurs, dome-headed pachycephalosaurs, and a number of horned dinosaurs, such as Utahceratops, Kosmoceratops, Nasutoceratops, and Machairoceratops. Other fossil discoveries include fossil plants, insect traces, snails, clams, fishes, amphibians, lizards, turtles, crocodiles, and mammals. Together, this diverse bounty of fossils is offering one of the most comprehensive glimpses into a Mesozoic ecosystem. Remarkably, virtually all of the dinosaur species found in GSENM appear to be unique to this area, and are not found anywhere else on Earth.

Saber-toothed cat evolution, new research


This 2017 video from the USA is called Prehistoric Predators – Sabertooth.

From ScienceDaily:

Ancient DNA offers new view on saber-toothed cats‘ past

October 19, 2017

Researchers who’ve analyzed the complete mitochondrial genomes from ancient samples representing two species of saber-toothed cats have a new take on the animals’ history over the last 50,000 years. The data suggest that the saber-toothed cats shared a common ancestor with all living cat-like species about 20 million years ago. The two saber-toothed cat species under study diverged from each other about 18 million years ago.

“It’s quite crazy that, in terms of their mitochondrial DNA, these two saber-toothed cats are more distant from each other than tigers are from house cats,” says Johanna Paijmans at the University of Potsdam in Germany.

Paijmans and colleagues reconstructed the mitochondrial genomes from ancient-DNA samples representing three Homotherium from Europe and North America and one Smilodon specimen from South America. One of the Homotherium specimens under investigation is a unique fossil: a 28,000-year-old mandible recovered from the North Sea.

“This find was so special because Homotherium is generally believed to have gone extinct in Europe around 300,000 years ago, so [this specimen is] over 200,000 years younger than the next-to-youngest Homotherium find in Europe,” Paijmans explains.

The new DNA evidence confirmed that this surprisingly young specimen did indeed belong to a Homotherium. The discovery suggests that the saber-toothed cats continued to live in Europe much more recently than scientists previously thought.

“When the first anatomically modern humans migrated to Europe, there may have been a saber-toothed cat waiting for them,” Paijmans says.

The finding raises new questions about how and why the saber-toothed cats went extinct. Paijmans says they are now interested in studying DNA from other samples of saber-toothed cats. Although it will be technically challenging, they also hope to recover and analyze DNA from much older Homotherium specimens.

This project received funding from the European Research Council, the European Union’s Seventh Framework Programme for research, technological development, and demonstration and the Lundbeck Foundation.

Fossil sea turtle baby, new research


Tasbacka danica, photo by Johan Lindgren

From North Carolina State University in the USA:

Keratin, proteins from 54-million-year-old sea turtle show survival trait evolution

October 17, 2017

Researchers from North Carolina State University, Lund University in Sweden and the University of Hyogo in Japan have retrieved original pigment, beta-keratin and muscle proteins from a 54 million-year-old sea turtle hatchling. The work adds to the growing body of evidence supporting persistence of original molecules over millions of years and also provides direct evidence that a pigment-based survival trait common to modern sea turtles evolved at least 54 million years ago.

Tasbacka danica is a species of sea turtle that lived during the Eocene period, between 56 and 34 million years ago. In 2008 an extremely well-preserved T. danica hatchling was recovered from the Für formation in Jutland, Denmark. The specimen was less than 3 inches (74 millimeters) long. In 2013 paleontologist Johan Lindgren of Lund University uncovered soft tissue residues from an area located near the sea turtle’s left “shoulder.” He collected five small samples for biomolecular analysis.

The shells of modern sea turtle hatchlings are dark colored — this pigmentation gives them protection from aerial predators (such as seagulls) as they float on the ocean surface to breathe. Since turtles are reptiles, and therefore cold-blooded, the dark coloration also allows them to absorb heat from sunlight and regulate their body temperature. This elevated body temperature also allows more rapid growth, reducing the time they are vulnerable at the ocean surface.

The T. danica hatchling specimen appeared to share this coloration with its living counterparts. The researchers observed round organelles in the fossil that could be melanosomes, pigment-containing structures in the skin (or epidermis) that give turtle shells their dark color.

To determine the structural and chemical composition of the soft tissues Lindgren collected and see if the fossil sea turtle did have a dark colored shell, the researchers subjected the sample to a selection of high-resolution analytical techniques, including field emission gun scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM), in situ immunohistochemistry, time-of-flight secondary ion mass spectrometry (ToF-SIMS), and infrared (IR) microspectroscopy.

Lindgren performed ToF-SIMS on the samples to confirm the presence of heme, eumelanin and proteinaceous molecules — the components of blood, pigment and protein.

Co-author Mary Schweitzer, professor of biological sciences at NC State with a joint appointment at the North Carolina Museum of Natural Sciences, performed histochemical analyses of the sample, finding that it tested positive against antibodies for both alpha and beta-keratin, hemoglobin and tropomyosin, a muscle protein. TEM, performed by University of Hyogo evolutionary biologist Takeo Kuriyama, and Schweitzer’s immunogold testing further confirmed the findings.

In the end, the evidence pointed to these molecules as being original to the specimen, confirming that these ancient turtles shared a pigmentation-based survival trait with their modern-day brethren.

“The presence of eukaryotic melanin within a melanosome embedded in a keratin matrix rules out contamination by microbes, because microbes cannot make eukaryotic melanin or keratin,” Schweitzer says. “So we know that these hatchlings had the dark coloration common to modern sea turtles.

“The data not only support the preservation of multiple proteins, but also suggest that coloration was used for physiology as far back as the Eocene, in the same manner as it is today.”

The scientific report on this is here.

Extinct fanged kangaroos, new research


This video says about itself:

The Fossil Record and Evolution of Kangaroos

28 February 2016

I would first like to give visual credit to BBC Earth, which they have some epic shots on kangaroos.

From the University of Queensland in Australia:

Fanged kangaroo research could shed light on extinction

October 16, 2017

Fanged kangaroos — an extinct family of small fanged Australian kangaroos — might have survived at least five million years longer than previously thought.

A University of Queensland-led study has found the species might have competed for resources with ancestors of modern kangaroos.

Research into species diversity, body size and the timing of extinction found that fanged kangaroos, previously thought to have become extinct about 15 million years ago, persisted to at least 10 million years ago.

The fanged kangaroos, including the species Balbaroo fangaroo, were about the size of a small wallaby.

UQ School of Earth and Environmental Sciences PhD student Kaylene Butler said the research involved Queensland Museum holdings of ancient fossil deposits from the Riversleigh World Heritage Area, where kangaroo fossil evidence goes back as far as 25 million years.

“Fanged kangaroos and the potential ancestors of modern kangaroos are both browsers — meaning they ate leaves — and they scurried, but did not hop,” Ms Butler said.

“Northern Queensland was predominantly covered in rainforest when these fanged kangaroos first appear in the fossil record.

“There is a lot of research to be done before we can be sure what their canine teeth were used for but some have suggested they were used to attract potential mates. We do know that despite their large canines they were herbivorous (plant eaters).

“We found that fanged kangaroos increased in body size right up until their extinction.”

Ms Butler said the research aimed to fill significant gaps in the understanding of kangaroo evolution, and new fossil finds were helping to bring ancient lineages into focus.

“Currently 21 macropod species are listed as vulnerable or endangered on the International Union for the Conservation of Nature Red List of Threatened Species,” she said.

She said understanding when and why kangaroos went extinct in the past could help with understanding what drove extinction of such animals.

“Currently, we can only hypothesise as to why balbarids became extinct — the original hypothesis related to events during a change in climate 15 million years ago but the balbarids persisted past that,” she said.

“This new finding of their persistence until 10 million years ago means something else must have been at play, such as being outcompeted by other species.”

Ms Butler last year discovered two new ancient species of kangaroo, Cookeroo bulwidarri and Cookeroo hortusensis.

She has worked on fossil material as part of her PhD research supervised by former UQ Robert Day Fellow Dr Kenny Travouillon, now of the Western Australian Museum, and UQ’s Dr Gilbert Price.