South Africa’s oldest Australopithecus fossil


This video from South Africa says about itself:

6 December 2017

The Australopithecus fossil, Little Foot, was discovered by Wits [University of the Witwatersrand] palaeoanthropologist Ron Clarke.

From the University of the Witwatersrand in South Africa:

Litte Foot takes a bow

South Africa’s oldest, and the world’s most complete Australopithecus skeleton ever found, introduced to the world

December 6, 2017

South Africa’s status as a major cradle in the African nursery of humankind has been reinforced with today’s unveiling of “Little Foot”, the country’s oldest, virtually complete fossil human ancestor.

Little Foot is the only known virtually complete Australopithecus fossil discovered to date. It is by far the most complete skeleton of a human ancestor older than 1.5 million years ever found. It is also the oldest fossil hominid in southern Africa, dating back 3.67 million years. The unveiling will be the first time that the completely cleaned and reconstructed skeleton can be viewed by the national and international media.

Discovered by Professor Ron Clarke from the Evolutionary Studies Institute at the University of the Witwatersrand in Johannesburg, South Africa, the fossil was given the nickname of “Little Foot” by Prof. Phillip Tobias, based on Clarke’s initial discovery of four small footbones. Its discovery is expected to add a wealth of knowledge about the appearance, full skeletal anatomy, limb lengths and locomotor abilities of one of the species of our early ancestral relatives.

“This is one of the most remarkable fossil discoveries made in the history of human origins research and it is a privilege to unveil a finding of this importance today,” says Clarke.

After lying undiscovered for more than 3.6 million years deep within the Sterkfontein caves about 40km north-west of Johannesburg, Clarke found several foot bones and lower leg bone fragments in 1994 and 1997 among other fossils that had been removed from rock blasted from the cave years earlier by lime miners. Clarke sent his assistants Stephen Motsumi and Nkwane Molefe into the deep underground cave to search for any possible broken bone surface that might fit with the bones he had discovered in boxes. Within two days of searching, they found such a contact, in July 1997.

Clarke realised soon after the discovery that they were on to something highly significant and started the specialised process of excavating the skeleton in the cave up through 2012, when the last visible elements were removed to the surface in blocks of breccia. “My assistants and I have worked on painstakingly cleaning the bones from breccia blocks and reconstructing the full skeleton until the present day,” says Clarke.

In the 20 years since the discovery, they have been hard at work to excavate and prepare the fossil. Now Clarke and a team of international experts are conducting a full set of scientific studies on it. The results of these studies are expected to be published in a series of scientific papers in high impact, peer reviewed international journals in the near future.

This is the first time that a virtually complete skeleton of a pre-human ancestor from a South African cave has been excavated in the place where it was fossilised.

“Many of the bones of the skeleton are fragile, yet they were all deeply embedded in a concrete-like rock called breccia,” Clarke explains.

“The process required extremely careful excavation in the dark environment of the cave. Once the upward-facing surfaces of the skeleton’s bones were exposed, the breccia in which their undersides were still embedded had to be carefully undercut and removed in blocks for further cleaning in the lab at Sterkfontein,” says Clarke.

The 20-year long period of excavation, cleaning, reconstruction, casting, and analysis of the skeleton has required a steady source of funding, which was provide by the Palaeontological Scientific Trust (PAST) — a Johannesburg-based NGO that promotes research, education and outreach in the sciences related to our origins. Among its many initiatives aimed at uplifting the origin sciences across Africa, PAST has been a major funder of research at Sterkfontein for over two decades.

Professor Adam Habib, Vice-Chancellor and Principal of the University of the Witwatersrand says: “This is a landmark achievement for the global scientific community and South Africa’s heritage. It is through important discoveries like Little Foot that we obtain a glimpse into our past which helps us to better understand our common humanity.”

PAST’s chief scientist Professor Robert Blumenschine labels the discovery a source of pride for all Africans. “Not only is Africa the storehouse of the ancient fossil heritage for people the world over, it was also the wellspring of everything that makes us human, including our technological prowess, our artistic ability, and our supreme intellect,” he says.

The scientific value of the find and much more will be unveiled in a series of papers that Prof Clarke and a team of international experts have been preparing, with many expected in the next year.

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Jurassic semi-marine reptile discovery


Vadasaurus herzogi, image credits Gabriel Bever, Mark Norell, 2017, Nature

From Johns Hopkins Medicine in the USA:

Recently discovered fossil shows transition of a reptile from life on land to life in the sea

Modern New Zealand reptile may be a close relative

December 6, 2017

Using modern research tools on a 155-million-year-old reptile fossil, scientists at Johns Hopkins and the American Museum of Natural History report they have filled in some important clues to the evolution of animals that once roamed land and transitioned to life in the water.

A report on the new discoveries about the reptile, Vadasaurus herzogi, appears online in the Nov. 8 issue of Royal Society Open Science, and suggests that some of the foot-long animal’s features, including its elongated, whip-like tail, and triangular-shaped head, are well suited to aquatic life, while its relatively large limbs link it to land-loving species.

Vadasaurus, which is the Latin term for “wading lizard,” was discovered in limestone quarries near Solnhofen, Germany, part of a once-shallow sea long explored for its rich trove of fossil finds.

The well-preserved fossil is housed in the American Museum of Natural History in New York, where the job of unlocking its evolutionary secrets fell to museum research associate Gabriel Bever, Ph.D., who is also assistant professor of functional anatomy and evolution at the Johns Hopkins University School of Medicine, and Mark Norell, Ph.D., the museum’s paleontology division chair.

“Anatomic and behavioral characteristics of modern groups of living things accumulated over long spans of time,” says Bever. “Fossils can teach us a lot about that evolutionary history, including the order in which those features evolved and their adaptive role in a changing environment.”

“Anytime we can get a fossil like this that is so well preserved, and so significant in understanding a major environmental transition, it is very important,” says Norell. “It’s so important,” he adds, “that we can consider Vadasaurus to be the Archaeopteryx of rynchocephalians.”

According to Bever, their work adds to the list of sea creatures whose ancestors were land-dwelling vertebrates. They include modern-day whales, seals, and sea snakes, and ancient (and now-extinct) species of ichthyosaurs, mosasaurs, and plesiosaurs.

Bever says their study offers evidence that Vadasaurus, likely an adult when it died, can be linked by its anatomy to a small group of marine species called pleurosaurs, which have long been thought to have terrestrial roots. Pleurosaurs lived during the Jurassic period, 185 to 150 million years ago. The eel-like creatures had reduced limbs that were probably used for steering rather than propulsion in the water. Until now, fossils of only three ancient species of pleurosaurs have been discovered.

Using two types of statistical algorithms and reconstructions of evolutionary “trees,” Bever and Norell say that Vadasaurus and the pleurosaurs are part of a larger lineage of reptiles called Rhynchocephalia. Like the sea-loving pleurosaurs, Vadasaurus’ skull was a triangular shape, an adaptation found among many streamlined, water-dwelling animals, such as most fish, eels and whales. An elongated snout, common among sea animals, featured teeth farther away from the body for ensnaring fish.

By examining the shape and structure of the Vadasaurus’ skull, Bever and Norell also concluded that Vadasaurus’ bite was likely a quick, side-to-side motion, compared with the slower, stronger bite typical of many land-dwelling animals.

Some 155 million years ago, Vadasaurus’ tail had begun to lengthen like most modern sea animals, says Bever, but not to the size of the 5-foot pleurosaur. Vadasaurus, they found, had 24 pre-sacral vertebrae, which span from the head to the beginning of the tail, whereas pleurosaurus had more than 50 such back bones.

Despite its aquatic features, Vadasaurus retained some features more often found among land vertebrates. For example, Vadasaurus still had the large limbs, relative to the size of its body, expected of a land-dwelling reptile. Bever speculates that Vadasaurus did not use its limbs for propulsion in the water, but to steer. He says Vadasaurus may have swum like a modern sea snake, moving its spinal column with an undulating kind of motion.

“Our data indicate that Vadasaurus is an early cousin of the pleurosaur,” says Bever. “And these two reptiles are closely related to modern tuatara.” The modern tuatara is a lizard-like, land-dwelling reptile that lives on New Zealand’s coastal islands and is the single remaining species of rhynchocephalian still left on Earth.

Bever notes that a complete evolutionary history of Vadasaurus will require more data and fossil finds.

“We don’t know exactly how much time Vadasaurus was spending on land versus in the water. It may be that the animal developed its aquatic adaptations for some other reason, and that these changes just happened to be advantageous for life in the water,” says Bever.

See also here.

‘Haarlem museum archaeopteryx not archaeopteryx’


This video says about itself:

Haarlem, Netherlands museums and big church

17 November 2016

Bringing you into a couple of the really great Haarlem museums, Frans Hals Museum and Teylers Museum, and showing you a few other smaller museums, and into the big church, the Grote Kerk.

Frans Hals Museum is one of the top attractions of Haarlem.

The museum is located in the old part of town in a building that dates back to 1609 and was originally a retirement home for single old men.

Inside are works by many other Haarlem artists of the 17th century. Several stately rooms saved from torn down houses have been partially reconstructed from other Haarlem locations with period furniture and decor.

Of course the main attraction are the paintings – 16 of them by Frans Hals, who lived most of his life in Haarlem, between 1616 and 1664, keeping very busy creating many individual portraits, and especially famous for the large group ensembles.

In this principal room it seems like you have entered a great banquet hall divided up in different tables. And as you walk in it seems all the guests have turned around to look at you. There are groups of officers and administrators of the hospital, life-sized, some of them seated with faces turned to the spectator as if posing for a photograph, some standing, all splendidly decorated.

Hals was the master of showing emotional expression in faces. You really feel as if you know these people, as if you’d met them before. This truth of expression and the jovial character, and the ample rich costumes of the 16th century make it seem like you’re really looking at the Holland of 300 years ago – as if you’re a watching historical play, not just an art gallery. The solo portraits are equally powerful as the groups.

Teylers Museum is the oldest historical museum in the Netherlands and the interior retains that very old-fashioned feeling, like stepping back into 1778 when it was established.

Right away upon entering the first room you’ll notice these display cases with that original feeling.

The room is mostly fossils and bones of old creatures, including some remnants of early human and prehuman, and the first example ever found of the Archaeopteryx, a flying dinosaur.

Next we enter a room filled with the variety of scientific instruments including what had been the world’s largest electrostatic generator from the 18th century, old telescopes, microscopes, recording devices, telephones, whatnot.

A small darkened room showcases luminescent minerals. Then we get to the most famous gallery in the museum. It’s the Oval Room that dates back to its founding in the late 1700s with mineral displays in the center and all around it, scientific instruments from the 18th century. The room was designed for research and study with scientific experiments conducted here, and public demonstrations held – in the upper level archives and a library.

More museums, then the big church, Grote Kerk. This impressive church has been the heart of the city and its most important landmark for centuries. Located right in the middle of the market square, it was built in the Gothic style of architecture, originally as a Catholic Church between 1370 and 1520 when it was finished.

From the Ludwig-Maximilians-Universitaet Muenchen in Germany:

Early avian evolution: The Archaeopteryx that wasn‘t

December 4, 2017

Paleontologists at Ludwig-Maximilians-Universitaet (LMU) in Munich correct a case of misinterpretation: The first fossil “Archaeopteryx” to be discovered is actually a predatory dinosaur belonging to the anchiornithid family, which was previously known only from finds made in China.

Even 150 million years after its first appearance on our planet, Archaeopteryx is still good for surprises. The so-called Urvogel has attained an iconic status well beyond the world of paleontology, and it is one of the most famous fossils ever recovered. In all, a dozen fossil specimens have been assigned to the genus. Archaeopteryx remains the oldest known bird fossil, not only documenting the evolutionary transition from reptiles to birds, but also confirming that modern birds are the direct descendants of carnivorous dinosaurs. LMU paleontologist Oliver Rauhut and Christian Foth from the Staatliches Museum für Naturkunde in Stuttgart have re-examined the so-called Haarlem specimen of Archaeopteryx, which is kept in Teylers Museum in that Dutch city and has gone down in history as the first member of this genus to be discovered.

In the journal BMC Evolutionary Biology, Foth and Rauhut now report that this fossil differs in several important respects from the other known representatives of the genus Archaeopteryx. In fact, their taxonomic analysis displaces it from its alleged perch on the phylogenetic tree: “The Haarlem specimen is not a member of the Archaeopteryx clade,” says Rauhut, a paleontologist in the Department of Earth and Environmental Sciences at LMU who is also affiliated with the Bavarian State Collections for Paleontology and Geology in Munich.

Instead, the two scientists assign the fossil to a group of bird-like maniraptoran dinosaurs known as anchiornithids, which were first identified only a few years ago based on material found in China. These rather small dinosaurs possessed feathers on all four limbs, and they predate the appearance of Archaeopteryx. “The Haarlem fossil is the first member of this group found outside China. And together with Archaeopteryx, it is only the second species of bird-like dinosaur from the Jurassic discovered outside eastern Asia. This makes it even more of a rarity than the true specimens of Archaeopteryx,” Rauhut says.

Made in China

The Haarlem specimen was found about 10 km to the northeast of the closest Archaeopteryx locality known (Schamhaupten) a full four years before the discovery of the skeleton that would introduce the Urvogel to the scientific world in 1861. Schamhaupten was once part of the so-called Solnhofen archipelago in the Altmühl Valley in southern Bavaria, the area from which all known specimens of the genus Archaeopteryx originated. Its taxonomic reassignment therefore provides new insights into the evolution of the bird-like dinosaurs in the Middle to Late Jurassic. “Our biogeographical analysis demonstrates that the group of dinosaurs that gave rise to birds originated in East Asia — all of the oldest finds have been made in China. As they expanded westward, they also reached the Solnhofen archipelago,” says Christian Foth. Thus, the fossil hitherto incorrectly assigned to the genus Archaeopteryx must have been one of the first members of the group to arrive in Europe.

Around 150 million years ago, the area known today as the Altmühl Valley was dotted with the coral and sponge reefs and lagoons of the Solnhofen archipelago, and the open sea lay to the West and South. The Haarlem fossil was originally recovered from what was then the eastern end of the archipelago, quite close to the mainland. Unlike Archaeopteryx, anchiornithids were unable to fly, and might not have been able to reach areas further offshore. On the other hand, all true fossils of Archaeopteryx found so far were recovered from the lithographic limestone strata further to the west, closer to the open sea. Based on the new findings, Rauhut argues that other known Archaeopteryx fossils may need reassessment: “Not every bird-like fossil that turns up in the fine-grained limestones around Solnhofen need necessarily be a specimen of Archaeopteryx,” he points out.

The authors of the new study have proposed that the Haarlem specimen be assigned to a new genus, for which they suggest the name Ostromia — in honor of the American paleontologist John Ostrom, who first identified the fossil as a theropod dinosaur.

Mammoth discoveries in Michigan, USA


This video from the USA says about itself:

30 November 2017

University of Michigan paleontologists conducted a second excavation this week at the Chelsea-area farm where the skull, tusks and dozens of intact bones of an ice age mammoth were pulled from the ground in late 2015.

A U-M news video of the skull and two attached tusks being hoisted from the muddy excavation pit with a backhoe on October 1, 2015, has been viewed more than 875,000 times on YouTube.

From the University of Michigan in the USA:

More mammoth bones recovered from Michigan farm where skull, tusks and dozens of intact bones of an ice age mammoth were found

November 30, 2017

University of Michigan paleontologists conducted a second excavation this week at the Chelsea-area farm where the skull, tusks and dozens of intact bones of an ice age mammoth were pulled from the ground in late 2015.

A U-M news video of the skull and two attached tusks being hoisted from the muddy excavation pit with a backhoe on Oct. 1, 2015, has been viewed more than 875,000 times on YouTube.

Nothing that dramatic happened during the two-day follow-up. But 40 additional bones and bone fragments from the Bristle Mammoth were recovered, and the researchers were able to thoroughly document the site. That just wasn’t possible two years ago, in the one-day rush to get the skull and tusks out of the ground.

“This return to the Bristle site was absolutely a success. We got the kind of information that we need to do the science right, and we were also able to recover an impressive amount of additional material from this animal,” said U-M paleontologist Daniel Fisher, who led both Bristle digs and who is overseeing the analysis of the bones and the environmental samples.

“So I’m confident that as a result of this second excavation, we’ll have more insight into what happened here,” said Fisher, director of the U-M Museum of Paleontology.

Bristle’s farm deserved a second visit in part because a single radiocarbon date from one of the mammoth bones showed the animal to be more than 15,000 years old. Also, several lines of evidence point to human processing of the mammoth carcass for food.

If additional studies substantiate those preliminary findings, the Bristle Mammoth “would represent the earliest instance of human interaction with a mammoth in the eastern Great Lakes basin,” Fisher said.

The U-M team had been trying to make a return trip to Bristle’s farm for a while but needed to find a time that worked for Fisher, excavator James Bollinger and farmer James Bristle, who harvested corn from the dig site in October.

“The crops are off, so it’s really a perfect time to do it,” Bristle said Tuesday morning as Bollinger began removing soil from a site directly south of the October 2015 excavation.

“It was such a hurried thing the first time around,” said Bristle, who renamed his farm Mammoth Acres after that find. “So this is an opportunity to complete the discovery process.”

The first mammoth bones were discovered while Bristle was installing a drainage system at a low spot in one of his fields. The farmer gave U-M researchers one day to recover whatever remains they could find; after that, the drainage project and his harvest for the year needed to resume.

Bristle later donated the mammoth remains to the university, and some of them are now on display at the U-M Museum of Natural History. This week, additional bones were found in clays that were disturbed in 2015 when a sump pump was installed as part of the drainage project. The newly discovered bones will also be donated to the university, Bristle said.

During the first Bristle dig, 55 to 60 nearly complete mammoth bones were found, accounting for 30 to 40 percent of the animal’s skeletal mass. The animal was a male in its mid-40s and would have weighed about 9 tons.

In addition to the skull with teeth and tusks, most of the vertebrae and ribs were found, along with parts of the shoulder blades and the pelvis. Notably missing are the limb and foot bones and the tail vertebrae.

This week, the researchers added 40 more bones and bone fragments, including several vertebrae, skull fragments, an intact rib, part of a shoulder blade, a piece of the pelvis, and what appears to be part of the mandible.

Most of the workers in the muddy pit with Fisher were current or former U-M students. Scott Johnston, a 2017 graduate in the Department of Earth and Environmental Sciences who has worked at the U-M Museum of Natural History since he was 14, found a jagged, softball-sized fragment of the mammoth‘s skull on Wednesday.

“I knew immediately that it was skull bone because nothing else looks exactly like it,” Johnston said. “The feeling was pure euphoria.”

Nichole Lohrke was a double major in German and evolutionary anthropology two years ago when she heard about the Bristle mammoth discovery. A few months later, she went to work in Fisher’s lab, repairing the Bristle tusks and skull. She added a minor in paleontology, graduated last spring, and on Wednesday found a plum-sized piece of the animal’s skull.

“The first Bristle excavation is what inspired me to get into paleontology,” she said. “I heard about it on the news and thought, ‘That is so cool. I would love to be part of that.’ And now I’m here.”

One goal of the second Bristle excavation was to find more bones and, possibly, additional evidence of human involvement. But an even higher priority was to reconstruct the geological context of the mammoth remains, something that simply wasn’t possible during 2015’s get-what-you-can-in-a-day dig.

The Bristle bones were found about 10 feet below the current land surface, in fine-grained clays and marls from the bottom of a pond that no longer exists.

On Tuesday of this week, the researchers dug a pit just south of the October 2015 location and collected sediment samples from the layers exposed in one of the walls. They collected samples at 2-inch intervals, from a couple feet below the top of the pit wall to the gravel at its bottom, a distance of about 13 feet. The gravel at the bottom of the pit is from a time 17,000 to 18,000 years ago, when glacial ice still covered the region, Fisher said.

Organic material from some of the samples will be radiocarbon-dated. If the dates grow steadily older with increasing depth, as expected, the researchers can have increased confidence in the dates of the Bristle Mammoth bones.

Pollen grains and fungal spores will be extracted from the sediments and analyzed to help reconstruct ancient environments and to provide proper context for the mammoth find.

Spores from the Sporormiella fungus are found today in the dung of domestic livestock animals as well as wild herbivores. The spores are preserved in recognizable form for thousands of years and are used in paleoecological studies as a proxy for the abundance of ancient grazing mammals such as mammoths.

If the fungal spores are found in the various ancient sediment layers at the Bristle site, their distribution could reveal when grazing mammals were present at the site as well as the timing of their local extinction.

Pollen grains would show what types of plants were growing at the time of the Bristle Mammoth and how the vegetation mix changed over time as the climate shifted.

The oldest well-documented, published evidence for humans in Michigan is about 13,000 years ago, the age of the spear-wielding Clovis hunters. But several lines of evidence from the Bristle Mammoth, including the single radiocarbon date, imply that humans processed the carcass more than 2,000 years before the Clovis hunters arrived.

The Bristle Mammoth remains were found in pond sediments. Fisher suspects early humans butchered the carcass and placed selected portions at the bottom of the pond for storage, using boulders to anchor their meat stash.

Examination of the sediments revealed during this week’s dig suggest the pond was small, perhaps only 20 to 30 yards across, said Fisher, a professor in the Department of Earth and Environmental Sciences and in the Department of Ecology and Evolutionary Biology.

The weather was ideal for this week’s two-day dig, with sunny skies and unseasonably warm temperatures both days. Excavation costs of the second dig are being covered by Friends of the University of Michigan Museum of Paleontology, a group of avocational paleontologists associated with the university.

215 pterosaur eggs discovered


This video says about itself:

30 November 2017

They were known to rule the skies in the Jurassic and Cretaceous periods, but it seems that pterosaurs had a slow start in life. A new study has revealed that the giant reptiles had a two year incubation and couldn’t fly when they hatched. The findings suggest that young pterosaurs were ‘less precocious than previously assumed.’ The researchers analysed 215 eggs of the pterosaur species Hamipterus tianshanensis found in China.

From the American Association for the Advancement of Science in the USA:

Hundreds of fossilized eggs shed light on pterosaur development

November 30, 2017

An invaluable collection of more than 200 eggs is providing new insights into the development and nesting habits of pterosaurs.

To date, only a small handful of pterosaur eggs with a well-preserved 3-D structure and embryo inside have been found and analyzed — three eggs from Argentina and five from China. This sparse sample size was dramatically increased upon the discovery of 215 eggs of the pterosaur species Hamipterus tianshanensis from a Lower Cretaceous site in China.

Xiaolin Wang et al. used computed tomography scanning to peer inside the eggs, 16 of which contain embryonic remains of varying intactness. The most complete embryo contains a partial wing and cranial bones, including a complete lower jaw. The samples of thigh bones that remain intact are well-developed, suggesting that the species benefited from functional hind legs shortly after hatching.

However, the structure supporting the pectoral muscle appears to be underdeveloped during the embryonic stage, suggesting that newborns were likely not able to fly. Therefore, the authors propose that newborns likely needed some parental care. Based on growth marks, the team estimates one of the individuals to be at least 2 years old and still growing at the time of its death, supporting the growing body of evidence that pterosaurs had long incubation periods.

Lastly, the fact that a single collection of embryos exhibits a range of developmental stages hints that pterosaurs participated in colonial nesting behavior, the authors say. Denis Deeming discusses these findings in a related Perspective.

Dugong ancestor discovery in California


This video says about itself:

4 September 2015

Sirenia” are an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. Four species are living, in two families and genera. These are the dugong and manatees. Sirenia also include Steller’s sea cow, extinct since the 18th century, and a number of taxa known only from fossils. The order evolved during the Eocene, more than 50 million years ago.

From Associated Press:

Remains of ancient sea cow unearthed on California island

Nov 28, 2017

VENTURA, Calif. — Scientists say they’ve unearthed fossil remains of a sea cow that lived in the shallow waters off Southern California’s Channel Islands some 25 million years ago.

The fossil skull and rib cage were discovered this summer on Santa Rosa Island, about 50 miles northwest of Los Angeles, the National Park Service announced Tuesday.

Scientists say the remains may be from a previously unknown sea cow species but they won’t know for sure until the skull is analyzed by an expert.

Some fossilized remnants of at least from four other sea cows also were found nearby.

Sea cows are torpedo-shaped plant-eaters that graze in shallow waters and can grow up to 13 feet long. The only living species are the dugong and three types of manatee.

Two researchers from the U.S. Geological Survey found the skull and rib cage in a steep ravine while mapping earthquake faults, said Yvonne Menard of the park service. Erosion may have only recently revealed them.

“This sea cow may have only been exposed the past few years after being buried for millions of years,” said Jonathan Hoffman with the Santa Barbara Museum of Natural History, which is protecting the fossils.

“They’re embedded in rock and the top surface has been exposed,” Menard said.

That surface has been covered with plaster-impregnated bandages and burlap to protect the fossils until work to excavate them can resume in late spring, Menard said.

The work is slow because researchers need to formulate a plan to excavate in the wilderness area, Hoffman said.

Researchers hope to uncover the teeth of the sea cow, which could help determine the animal’s diet and its age when it died.

The sea cow also travelled without ever leaving home. The shallow sea floor where it died actually was located about 150 miles south, in the area of San Diego and Baja California, Hoffman said.

Over millions of years, the land moved northward with the movement of the Pacific tectonic plate and the sea floor was pushed up to nearly 1,400 feet above sea level.

See also here.

Feathered dinosaurs, new study


This video says about itself:

29 July 2016

Ali and Sean travel back 150 million years to the Jurassic period to get a look at a flying dinosaur called the Anchiornis. Tour guide Simon reveals that this dinosaur actually had feathers!

From the University of Bristol in England:

Feathered dinosaurs were even fluffier than we thought

November 28, 2017

A University of Bristol-led study has revealed new details about dinosaur feathers and enabled scientists to further refine what is potentially the most accurate depiction of any dinosaur species to date.

Birds are the direct descendants of a group of feathered, carnivorous dinosaurs that, along with true birds, are referred to as paravians — examples of which include the infamous Velociraptor.

Researchers examined, at high resolution, an exceptionally-preserved fossil of the crow-sized paravian dinosaur Anchiornis — comparing its fossilised feathers to those of other dinosaurs and extinct birds.

The feathers around the body of Anchiornis, known as contour feathers, revealed a newly-described, extinct, primitive feather form consisting of a short quill with long, independent, flexible barbs erupting from the quill at low angles to form two vanes and a forked feather shape.

The observations were made possible by decay processes that separated some of these feathers from the body prior to burial and fossilisation, making their structure easier to interpret.

Such feathers would have given Anchiornis a fluffy appearance relative to the streamlined bodies of modern flying birds, whose feathers have tightly-zipped vanes forming continuous surfaces. Anchiornis’s unzipped feathers might have affected the animal’s ability to control its temperature and repel water, possibly being less effective than the vanes of most modern feathers. This shaggy plumage would also have increased drag when Anchiornis glided.

Additionally, the feathers on the wing of Anchiornis lack the aerodynamic, asymmetrical vanes of modern flight feathers, and the new research shows that these vanes were also not tightly-zipped compared to modern flight feathers. This would have hindered the feather’s ability to form a lift surface. To compensate, paravians like Anchiornis packed multiple rows of long feathers into the wing, unlike modern birds, where most of the wing surface is formed by just one row of feathers.

Furthermore, Anchiornis and other paravians had four wings, with long feathers on the legs in addition to the arms, as well as elongated feathers forming a fringe around the tail. This increase in surface-area likely allowed for gliding before the evolution of powered flight.

To assist in reconstructing the updated look of Anchiornis, scientific illustrator Rebecca Gelernter worked with Evan Saitta and Dr Jakob Vinther, from the University of Bristol’s School of Earth Sciences and School of Biological Sciences, to draw the animal as it was in life.

The new piece represents a radical shift in dinosaur depictions and incorporates previous research.

The color patterns for Anchiornis are known from fossilised pigment studies, the outline of the flesh of the animal has been constructed by examining fossils under laser fluorescence, and previous work has described the multi-tiered layering of the wing feathers.

Evan Saitta said: “The novel aspects of the wing and contour feathers, as well as fully-feathered hands and feet, are added to the depiction.

“Most provocatively, Anchiornis is presented in this artwork climbing in the manner of hoatzin chicks, the only living bird whose juveniles retain a relic of their dinosaurian past, a functional claw.

“This contrasts much previous art that places paravians perched on top of branches like modern birds.

“However, such perching is unlikely given the lack of a reversed toe as in modern perching birds and climbing is consistent with the well-developed arms and claws in paravians.

“Overall, our study provides some new insight into the appearance of dinosaurs, their behavior and physiology, and the evolution of feathers, birds, and powered flight.”

Rebecca Gelernter added: “Paleoart is a weird blend of strict anatomical drawing, wildlife art, and speculative biology. The goal is to depict extinct animals and plants as accurately as possible given the available data and knowledge of the subject’s closest living relatives.

“As a result of this study and other recent work, this is now possible to an unprecedented degree for Anchiornis. It’s easy to see it as a living animal with complex behaviours, not just a flattened fossil.

“It’s really exciting to be able to work with the scientists at the forefront of these discoveries, and to show others what we believe these fluffy, toothy almost-birds looked like as they went about their Jurassic business.”