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.

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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.

Saber-toothed cats’ illnesses, new research


This video from the USA is about the La Brea Tar Pits and Natural History Museum and a saber-toothed cat.

From Science News in the USA:

Surgeon aims to diagnose deformities of extinct saber-toothed cats

By Lesley Evans Ogden

9:00am, October 13, 2017

Robert Klapper has examined scores of damaged and diseased human knees, hips and shoulders. But a visit to the La Brea Tar Pits and Museum introduced the orthopedic surgeon to the suffering of an extinct cat — and a scientific mystery. In 2000, Klapper took a break from his patients at Cedars-Sinai Medical Center in Los Angeles to visit the nearby tar pits, where myriad mammals and other animals (SN: 5/17/14, p. 18) have been getting stuck for the last 40,000 years. (Yes, modern birds and insects still wander in).

After examining a museum display of broad-snouted dire wolf (Canis dirus) skulls, Klapper made a beeline for the security guard and asked to see a curator. He badgered then collections manager Chris Shaw with questions about why the skulls looked so perfect — no signs of cancers, fractures or arthritis.

“Instead of throwing me out,” Klapper says, Shaw took Klapper into the bowels of the museum and pulled out a drawer of bones from saber-toothed cats (Smilodon fatalis), one of the abundant prehistoric animals preserved in the pits about 14,000 years ago. Klapper noticed a pelvis with a surface that reminded him of a medieval mace: One hip socket was spiky with sharp edges, a telltale sign of arthritis. At the healthy hip socket, the bone was billiard ball smooth.

That kind of bone damage did not happen overnight. The arthritic animal had been disabled for years, Klapper estimated, perhaps even from birth. The surgeon asked a favor: “I’d love to get a CT scan.” Signing out the ancient cat’s pelvis, he says, was a thrill.

Paleontologists have long debated whether saber-toothed cats were solitary or social hunters. If this lame cat had been unable to hunt for years, which is what its traumatized hip bone indicated to Klapper, it could have survived only with help from other cats.

Klapper scanned that fossilized cat pelvis but left the images untouched for years, occupied with his hospital job and hosting ESPN Radio’s Weekend Warrior, a health and sports program. Now, collaborating with Emily Lindsey, a paleoecologist at La Brea, Klapper plans to use more sophisticated radiology techniques to diagnose the deformity and possibly deduce clues about the cat’s lifestyle.

It’s still early days for the revitalized project, Lindsey cautions, but “I’m really excited about it.” The museum houses some 2,000 fossils of saber-toothed cats, several of which the two plan to scan in the months ahead.

Ancestor of apes, humans weighed five kilograms


Apes, humans family tree, image courtesy of University of Tübingen

From the American Museum of Natural History in the USA:

Last common ancestor of humans and apes weighed about five kilograms

Ape ancestor was about the size of a gibbon

October 12, 2017

New research suggests that the last common ancestor of apes — including great apes and humans — was much smaller than previously thought, about the size of a gibbon. The findings, published today in the journal Nature Communications, are fundamental to understanding the evolution of the human family tree.

“Body size directly affects how an animal relates to its environment, and no trait has a wider range of biological implications,” said lead author Mark Grabowski, a visiting assistant professor at the Eberhard Karls University of Tübingen in Germany who conducted the work while he was a postdoctoral fellow in the American Museum of Natural History’s Division of Anthropology. “However, little is known about the size of the last common ancestor of humans and all living apes. This omission is startling because numerous paleobiological hypotheses depend on body size estimates at and prior to the root of our lineage.”

Among living primates, humans are most closely related to apes, which include the lesser apes (gibbons) and the great apes (chimpanzees, gorillas, and orangutans). These “hominoids” emerged and diversified during the Miocene, between about 23 million to 5 million years ago. Because fossils are so scarce, researchers do not know what the last common ancestors of living apes and humans looked like or where they originated.

To get a better idea of body mass evolution within this part of the primate family tree, Grabowski and coauthor William Jungers from Stony Brook University compared body size data from modern primates, including humans, to recently published estimates for fossil hominins and a wide sample of fossil primates including Miocene apes from Africa, Europe, and Asia. They found that the common ancestor of apes was likely small, probably weighing about 12 pounds, which goes against previous suggestions of a chimpanzee-sized, chimpanzee-like ancestor.

Among other things, the finding has implications for a behavior that’s essential for large, tree-dwelling primates: it implies that “suspensory locomotion,” overhand hanging and swinging, arose for other reasons than the animal simply getting too big to walk on top of branches. The researchers suggest that the ancestor was already somewhat suspensory, and larger body size evolved later, with both adaptations occurring at separate points. The development of suspensory locomotion could have been part of an “arms race” with a growing number of monkey species, the researchers said. Branch swinging allows an animal to get to a prized and otherwise inaccessible food — fruit on the edges of foliage — and larger body would let them engage in direct confrontation with monkeys when required.

The new research also reveals that australopiths, a group of early human relatives, were actually on average smaller than their ancestors, and that this smaller size continued until the arrival of Homo erectus.

“There appears to be a decrease in overall body size within our lineage, rather than size simply staying the same or getting bigger with time, which goes against how we generally think about evolution,” Grabowski said.

Cambrian animal discovery in Utah, USA


This video says about itself:

20 June 2014

In this episode of Palaeo After Dark, the group talks about an interesting and enigmatic fossil species from the Burgess Shale called Siphusauctum gregarium, which looks somewhat like a crinoid but is possibly completely unrelated. The group also gets sidetracked into conversations about echinoderms, the importance of the Burgess Shale, and shipping grandfather clocks on the Oregon Trail.

From the University of Kansas in the USA:

Obscure’ stalked filter feeder lived in Utah some 500 million years ago

October 11, 2017

Summary: The only fossilized specimen of a species previously unknown to science — an ‘obscure’ stalked filter feeder — has just been detailed for the first time.

To the untrained eye, it looks like a flower crudely etched into rock — as if a child had scratched a picture of a bloom. But to the late fossil hunter Lloyd Gunther, the tulip shape he unearthed at Antimony Canyon in northern Utah looked like the remnant of an ancient marine animal.

Years ago, Gunther collected the rock and later gave it to researchers at the University of Kansas’ Biodiversity Institute — just one among thousands of such fossils he donated to the institute over the years.

But this find was the only fossilized specimen of a species previously unknown to science — an “obscure” stalked filter feeder. It has just been detailed for the first time in a paper appearing in the Journal of Paleontology.

“This was the earliest specimen of a stalked filter feeder that has been found in North America,” said lead author Julien Kimmig, collections manager for Invertebrate Paleontology at the Biodiversity Institute. “This animal lived in soft sediment and anchored into the sediment. The upper part of the tulip was the organism itself. It had a stem attached to the ground and an upper part, called the calyx, that had everything from the digestive tract to the feeding mechanism. It was fairly primitive and weird.”

Kimmig researches the taxonomy, stratigraphy and paleoecology of the Cambrian Spence Shale found in Utah and Idaho, where Gunther found the obscure filter feeder.

“The Spence Shale gives us soft-tissue preservation, so we get a much more complete biota in these environments,” he said. “This gives us a better idea of what the early world was like in the Cambrian. It’s amazing to see what groups of animals had already appeared over 500 million years ago, like arthropods, worms, the first vertebrate animals — nearly every animal that we have around today has a relative that already lived during those times in the Cambrian.”

In honor of fossil hunter Gunther, a preeminent collector who performed fieldwork from the 1930s to the 2000s, Kimmig and Biodiversity Institute colleagues Luke Strotz and Bruce Lieberman named the newly described species Siphusauctum lloydguntheri.

The stalked filter feeder is just the second animal placed within its genus, and the first Siphusauctum to be discovered outside the Burgess Shale, a fossil-rich deposit in the Canadian Rockies.

“What these animals were doing was filtering water to get food, like micro-plankton,” Kimmig said. “The thing is, where this one was located we only found a single specimen over a period of 60 years of collecting in the area.”

Kimmig said it isn’t yet known if the newly discovered stalked filter feeder lived a highly solitary life or if it drifted off from a community of similar animals.

“It’s hard to tell from a single specimen,” he said. “There were algae found right next to it, so it likely was transported there. The algae found with it were planktonic algae that were floating themselves. It could have fallen just next to it — but that would be a big coincidence — so that’s why we’re thinking it came loose from somewhere else and got mixed in with the algae.”

Kimmig and his KU colleagues say the newly described specimen varies in key areas from similar known species of stalked filter feeders from the Cambrian.

“There are several differences in how the animal looked,” Kimmig said. “If you look at the digestive tract preserved in this specimen, the lower digestive tract is closer to the base of the animal compared to other animals. The calyx is very slim — it looks like a white wine glass, whereas in other species it looks like a big goblet. What we don’t have in this specimen that the others have are big branches for filter feeding. We don’t know if those weren’t preserved or if this one didn’t have them.”

According to the researchers, there are no species alive today that claim lineage to Siphusauctum lloydguntheri. But Kimmig said there were a few contemporary examples that share similarities.

“The closest thing to the lifestyle — but not a relative — would be crinoids, commonly called sea lilies,” he said. “Unfortunately, there’s likely not a relative of Siphusauctum in the world anymore. We have thousands of similar fossil specimens in the Burgess Shale, but it’s hard to identify what these animals actually were. It might be possibly related to contemporary entoprocts, which are a lot smaller than this one — but it’s hard to tell if they’re related at all.”

Ultimately, the mysterious stalked filter feeder is a reminder of the strange and vast arc of evolution where species continuously come and go, according to Kimmig.

“It is enigmatic because we don’t have anything living that is exactly like it,” he said. “What is fascinating about this animal is we can clearly relate it to animals existing in the Cambrian and then we just don’t find it anymore. It’s just fascinating to see how evolution works. Sometimes it creates something — and it just doesn’t work out. We have some lineages like worms that lived long before the Cambrian and haven’t changed in appearance or behavior, then we have things that were around for a couple of million years and just disappeared because they were chance victims of mass extinctions.”