Wahlisaurus massarae: Paleontologists Find 200-Million-Year-Old Ichthyosaur Fossil

Saturday, February 3, 2018

Reconstruction of Wahlisaurus massarae. Image credit: James McKay.

The 200 million-year-old specimen is only the second known example of Wahlisaurus massarae, a species of ichthyosaur announced recently by a University of Manchester paleontologist.

Ichthyosaurs were predatory sea-going reptiles that ranged in size from 1 to 69 feet (0.3-21 m) long. They swam the world’s oceans for millions of years during the Triassic, Jurassic and Cretaceous periods.

Despite their profound adaptations to the aquatic realm, these reptiles disappeared about 30 million years before the end-Cretaceous mass extinction (65 million years ago) that marked the end for dinosaurs and the beginning of the age of mammals.

In 2016, a paleontologist and honorary scientist at the University of Manchester, Dean Lomax, described an ichthyosaur skeleton that he had examined in the collections of Leicester’s New Walk Museum and Art Gallery.

He spotted several unusual features of the bones and determined that the features were unique and represented a completely new species, Wahlisaurus massarae.

“When Wahlisaurus massarae was announced, I was a little nervous about what other paleontologists would make of it, considering the new species was known only from a single specimen,” Lomax said.

“As a scientist you learn to question almost everything, and be as critical as you can be.”

“My analysis suggested it was something new, but some paleontologists questioned this and said it was just ‘variation’ of an existing species.”

Photograph of Dean Lomax (left), Simon Carpenter (middle) and Deborah Hutchinson with the new specimen of Wahlisaurus massarae. Image credit: University of Manchester.

In the new study, Lomax teamed up with New Walk Museum paleontologist Mark Evans and Simon Carpenter, fossil collector of Somerset.

The study focuses on a specimen Lomax identified in Simon’s private collection, which is an almost complete coracoid bone (part of the pectoral girdle) that has exactly the same unique features of the same bone in Wahlisaurus massarae.

“You can only imagine my sheer excitement to find a specimen of Wahlisaurus massarae,” Lomax said.

“It was such a wonderful moment. When you have just one specimen, ‘variation’ can be called upon, but when you double the number of specimens you have it gives even more credibility to your research.”

The new discovery is from a time known as the Triassic-Jurassic boundary, right after a world-wide mass extinction.

For these reasons, the authors have been unable to determine exactly whether the ichthyosaur was latest Triassic or earliest Jurassic in age, although it is roughly 200 million-year-old.

The team’s results will be published in the Geological Journal.


D.R. Lomax et al. 2018. An ichthyosaur from the UK Triassic-Jurassic boundary: A second specimen of the leptonectid ichthyosaur Wahlisaurus massaraeLomax 2016. Geological Journal, in press; doi: 10.1002/gj.3155


Young Tourist Helps Edmonton Researchers in Discovery of Rare Colombian Fish Fossil

Saturday, February 3, 2018

This perfectly-preserved ancient fish fossil was discovered embedded in the flagstones of an old Colombian monastery by a young boy. (Oksana Vernygora)

Edmonton paleontologists are crediting a keen-eyed tourist for spotting a never-before-seen fish fossil in flagstones outside a Colombian monastery.

The perfectly-preserved "lizard fish" specimen is an estimated 90 million years old and has no modern relatives. The extremely rare specimen is the first fossil of its kind to ever be found in South America. 

"This fossil was one of those serendipitous, unexpected findings," said paleontologist Javier Luque, a PhD candidate at the University of Alberta's biological sciences department and co-author of the research paper on the find.


'Once in a lifetime discovery'

"It was kind of a once-in-a-lifetime discovery, in many ways."

The discovery was made in 2015 at the Monastery of La Candelaria by a young boy who spotted the outline of a fish in one of the flagstones outside the 17th-century building.

Curious about the strange rock, the boy snapped a photo and shared it with staff at Centro de Investigaciones Paleontologicas, a museum in nearby Ráquira, Boyaca. Workers there recognized it as a fossil right away and shared the discovery with the University of Alberta.

The long-jawed 'lizard fish' would have thrived in the oceans that once covered Colombia. (Oksana Vernygora)

The flagstone had been part of the busy pathway for more than 15 years, said Luque. 

"A kid was just walking around saw what he thought was a fish and sure enough, he took a photo with the inquiring mind of a child," Luque said.

"It was a fossil fish, perfectly preserved in two dimensions, just laying down, weathering as people were walking on top of it for so many years."


'Shocking to see'

The museum and the university often partner on fossil finds in the area, said Luque.

After getting the call, a team of U of A researchers joined the local paleontologists in retracing the boy's steps to locate and lift the stone for further examination.

Researchers were able to trace the origins of the fossil-bearing flagstone to a nearby abandoned quarry from where locals extracted slabs for construction several years ago.

The research paper on the fossil was recently published in the Journal of Systematic Paleontology.  It was co-authored by Oksana Vernygora, a fellow PhD candidate at the U of A led the research with assistance from her supervisor, and Allison Murray, a professor of biological sciences.

The rocks date from the Late Cretaceous period, and were deposited at a time when most of the northern Andes was underwater, which accounts for a rich record of marine life in the heart of the Andes mountains. 

"It's an entirely new group of fossil fish from the Cretaceous period in South America," Luque said. 


It has been named Candelarhynchus padillai, which combines  'Candelaria,' the name of the monastery where the fossil was discovered, and the Greek word for nose 'rhynchos,' due to its peculiar long and slender needle-like face.


And while the fossil's backstory has largely been explained, the fish tale has one more mystery.

Researchers lost touch with the boy who found the fossil. They have only his name.

They are hoping, with the recent publication of the research, the boy might eventually come forward, so they can give him proper credit.

"We certainly will make sure we properly acknowledge this discovery," Luque said. "It was the keen eye of a young kid that was able to recognize the shape of a fossil that we were not able to see for so many years. 

"It gives a beautiful message about keeping curious … and being able to see the world with fresh eyes."



Pittsburgh Paleontologist Says New Dino Discovery Disrupts A Major Biodiversity Theory

Friday, February 2, 2018

An artist's rendering of the Mansourasaurus shahinae, an African elephant-sized sauropod that lived about 80 million years ago. ANDREW MCAFEE / CARNEGIE MUSEUM OF NATURAL HISTORY

Mansourasaurus shahinae was a long-necked, plant eating dinosaur that lived during the late Cretaceous period, about 80 million years ago, and its discovery is disrupting a major theory in the field of paleontology.

Uncovered recently by a team of Egyptian paleontologists in the Sahara Desert, researchers believe the dinosaur would have resembled a smaller, Elephant-sized version of its cousin, the brontosaurus. The group published their findings Monday in the journal Nature Ecology and Evolution.

Matt Lamanna, paleontologist and principal dinosaur researcher at the Carnegie Museum of Natural History, helped study the skeleton after its discovery. He said fossils of more recent dinosaurs, like those that appeared 30 million years or less before going extinct, are rarely found in Africa -- but this one was remarkably well-preserved. 

"In fact, this is definitely the best dinosaur skeleton that's been found, probably within that entire time span in Africa," Lamanna said.

Parts of the Mansourasaurus shahinae's skull, ribs, shoulder and hind foot were found at the dig site.

Lamanna said it bears striking similarities to sauropods found in Europe, refuting a big theory in the field of paleontology that Africa was once an isolated continent. Mansourasaurus' discovery seems to prove that the creatures traveled between the two continents, and were not genetically isolated.

"To find a dinosaur from the end of the age of dinosaurs in Africa and have it be closely related to European dinosaurs was really exciting," Lamanna said. "It showed that this island continent hypothesis was at least not entirely correct, if not completely off base."

Lamanna said there's no current plan to move Mansourasaurus shahinae from Egypt at this time, though casts could be made to show parts of the specimen in other museums.


The Lost Continent of Laramidia

Tuesday, February 13, 2018

North America, 76 million years ago

In this article, we discuss the nature of North America in the Late Cretaceous Period. Between 100 and 70 million years ago, the entire continent was divided by a shallow sea. This sea was once filled with colossal marine lizards, long-necked plesiosaurs, toothed birds, and the occasional diving Pteranodon. The sea divided the land into two smaller continents: Appalachia in the east and Laramidia in the west. As residents of the eastern United States, we are saddened by the meager dinosaur fossils (so far) discovered in the east. However, the vast and exposed formations in the west tell an amazing story.

Fossil-bearing formations dot the landscape of Laramidia, from the North Slope of Alaska down into Mexico. Each formation exhibits a similar ecosystem to the other: there are always tyrannosaurs, horned dinosaurs (ceratopsians), duck-billed dinosaurs (hadrosaurs), and raptors (dromaeosaurs) among other creatures. However, there are always different species belonging to each group. Even formations of the same age, or nearly the same age, differ in their species when they occupy different latitudes on the continent. This suggests that there were multiple “mini-ecosystems” throughout Laramidia some seventy-five million years ago.

Around seventy million years ago, as continents shifted and climates grew colder, the sea began to dry up. This linked the mini-continents of Laramidia and Appalachia once again and opened vast new regions for land animals to inhabit. The fossils of this age suggest that the divided mini-ecosystems began to blend together. It was into this great new world that Tyrannosaurus rex appeared on the scene, occupying the role of top predator until the extinction of the dinosaurs sixty-five million years ago.

The divided continent of North America. Note that the column on the left displays only a small number of the dinosaurs in each ecosystems. Also note that the Kirtland Formation is slightly younger than the others displayed.

Earlier Burgess-Shale-Type Fossils Found in Greenland

Wednesday, January 31, 2018

Graham Budd has been critical of associations between Ediacaran fauna and Cambrian animals, and has also debunked alleged Precambrian animal ancestors such as Vernanimalcula (Stephen Meyer, Darwin’s Doubt, pp. 85, 90-91). Budd also was in attendance at the Darwin-doubting Altenberg 16 conference in 2008 (p. 292), confessing that the fossil record tells little about the origin of biological forms. This Cambrian expert from Uppsala University has a new paper in Geology describing new exquisitely-preserved fossils of the Burgess Shale type, but earlier. Along with lead writer Ben Slater, Graham Budd’s team unveils photographs of tiny but exquisite parts of arthropods, worms and other animals that burst into appearance in the Cambrian Explosion. What’s amazing is that these fossils were collected not in Canada or China, but in the northern reaches of Greenland.

The location, called Sirius Passet in Peary Land in the far north of Greenland, has been known as an early Cambrian fossil site, but it lies close to a geological fold belt. Having been heated to 200° C or more by metamorphism, most of the fossils at Sirius Passet have suffered thermal alteration and are difficult to interpret. Not far to the south, however, the team found sites in the same formation that escaped most of the alteration. News from Uppsala University describes how they found a “treasure trove of highly detailed fossils” of the Burgess Shale type.

The ‘Cambrian explosion’ of animal diversity beginning ~541 million years ago is a defining episode in the history of life. This was a time when the seas first teemed with animal life, and the first recognisably ‘modern’ ecosystems began to take shape.

Current accounts of this explosion in animal diversity rely heavily on records from fossilised shells and other hard parts, since these structures are the most likely to survive as fossils. However, since most marine animals are ‘soft-bodied’ this represents only a small fraction of the total diversity.

Rare sites of exceptional fossilisation, like the world-famous Burgess Shale, have revolutionised palaeontologists understanding of ‘soft-bodied’ Cambrian life. Because of the special conditions of fossilisation at these localities, organisms that did not produce hard mineralized shells or skeletons are also preserved. Such sites offer a rare glimpse into the true diversity of these ancient seas, which were filled with a dazzling array of soft and squishy predatory worms and arthropods (the group containing modern crustaceans and insects). [Emphasis added.]

Also important is that these fossils date earlier than the Burgess Shale by 10 million years (518 million instead of 508 million), and yet are recognizable as the same animals. This indicates that the Cambrian animals had a global distribution at the time they were fossilized. The same animals are found many thousands of miles apart on three continents.

Instead of the large, articulated fossils from China and Canada, those at the Greenland sites are made up of tiny fragments. So rich were the deposits, they often found 100 specimens in a 50-gram sample.

A team of palaeontologists from Uppsala (Ben Slater, Sebastian Willman, Graham Budd and John Peel) used a low-manipulation acid extraction procedure to dissolve some of these less intensively cooked mudrocks. To their astonishment, this simple preparation technique revealed a wealth of previously unknown microscopic animal fossils preserved in spectacular detail.

Most of the fossils were less than a millimetre long and had to be studied under the microscope. Fossils at the nearby Sirius Passet site typically preserve much larger animals, so the new finds fill an important gap in our knowledge of the small-scale animals that probably made up the majority of these ecosystems. Among the discoveries were the tiny spines and teeth of priapulid worms — small hook shaped structures that allowed these worms to efficiently burrow through the sediments and capture prey. Other finds included the tough outer cuticles and defensive spines of various arthropods, and perhaps most surprisingly, microscopic fragments of the oldest known pterobranch hemichordates — an obscure group of tube-dwelling filter feeders that are distant relatives of the vertebrates. This group became very diverse after the Cambrian Period and are among some of the most commonly found fossils in rocks from younger deposits, but were entirely unknown from the early Cambrian. This new source of fossils will also help palaeontologists to better understand the famously difficult to interpret fossils at the nearby Sirius Passet site, where the flattened animal fossils are usually complete, but missing crucial microscopic details.

The photos of the small carbonaceous fossils (SCFs) in the paper show exquisite details of identifiable Burgess Shale type animals. Pieces of trilobite cuticles were also found. Trilobites are among the most complex of Cambrian animals, possessing articulated limbs, eyes and multiple body systems for locomotion, digestion and survival. The authors seem most excited about finding the earliest pterobranch hemichordates (a type of filter feeder known in the Burgess Shale), recognizing that the worldwide distribution indicates an even earlier origin. The paper says,

Our report of early Cambrian pterobranch fragments confirms this hypothesis [of early origin], and their potential affinities to Graptolithina also suggest that the divergence and radiation of the pterobranch clades containing cephalodiscids and graptolites had a somewhat deeper, early Cambrian origin.

Nowhere do they suggest evidence for evolution or transitional forms. On the contrary, these new fossils confirm the picture of abrupt appearance and stasis. The best the team can say is that this fossil site offers “new insights” into the fossilization process and may “reshape our view” of this ‘episode’ known as the Cambrian explosion:

“The sheer abundance of these miniature animal fossils means that we have only begun to scratch the surface of this overlooked resource, but it is already clear that this discovery will help to reshape our view of the non-shelly animals that crawled and swam among the early Cambrian seas more than half a billion years ago,” says Sebastian Willman, researcher at the Department of Earth Sciences, Uppsala University.

Marshall Is Back

In 2013, U.C. Berkeley paleontologist Charles Marshall published a critique of Darwin’s Doubt in the journal Science that Stephen Meyer considered the first critical review to actually address the main argument in the book: the inability of standard evolutionary mechanisms to explain the origin of morphological novelty in the Cambrian period. Meyer wrote a four-chapter response to Marshall in the follow-up book, Debating Darwin’s Doubt (2015).

Late last year, Marshall wrote an article in Science (November 29, 2017) called “A tip of the hat to evolutionary change,” in which he reviewed another paper in the same issue that claims to reveal “an unexpectedly simple pattern of driver action in peak evolutionary success.” That paper by Žliobaitė et al concludes from the fossil record of herbivorous mammals that species rise toward success and decline toward extinction in a “hat shape” graph (thus his title).  In passing, Marshall admits that “one of the challenges of studying evolution … is the hierarchical structure of the evolutionary process.” What drives innovation: abiotic (environmental) processes or biotic processes, like competition? How do they work together? How simple is the rise to “evolutionary success”?

Though only peripherally related to evolutionary processes in the Cambrian explosion, Marshall’s article shows what he thinks these days about the origin of biological novelty. Old-fashioned Darwinian competition is a driver of extinction, he agrees, but what drives innovation?

The results of Žliobaitė and colleagues’ work also provide insight into the drivers of evolutionary innovation. The authors’ data for North America and Europe show that, although both biotic and abiotic factors contribute roughly equally to genus origination rates, neither contribution is statistically significant. As the authors note, this provides evidence that evolutionary innovation is not driven by biotic or abiotic external changes. Instead, the data support the idea that evolutionary innovation is influenced by intrinsic factors — the less-predictable origin of the ‘right’ variants at the right time, able to exploit either existing or new resources.

This statement indicates that nothing much has changed in his thinking. It appears Marshall still has no better tool for innovation than lucky mutations that just happen to arrive at the right time to be exploited. How this solution can possibly address the “hierarchical structure of the evolutionary process” leading to body plans with hierarchical levels of morphological innovation seems lost in academic jargon and generalizations.

The Greenland fossils are observational facts. Graham Budd’s team in that cold, remote, northern wasteland could look at those cold, hard facts under a microscope, seeing complexity that shouldn’t be there by any unguided natural process. If Charles Marshall had a better mechanism for innovation than sheer dumb luck, he has had years to announce it. Until and unless he does, Meyer’s thesis remains unchallenged: only intelligent design can account for the functional hierarchical organization revealed by the Cambrian animals.

Photo: Location in Greenland where fossils were found, by John S. Peel, via Uppsala University.

Source: Evolution News @DiscoveryCSC

Spectacular Dinosaur Stomping Grounds Discovered Just Outside D.C.

Wednesday, January 31, 2018

Photo: NASA/GSFC/Rebecca Roth.

Following Ray Stanford's 2012 discovery, a NASA volunteer works to excavate the slab containing the fossil footprints.

Some 110 million years ago, in the swamp that would become the Washington suburbs, a hulking, armored nodosaur trudged along a riverbank, leaving a telltale print in the mud. Offspring scrambled after it, while nearby, a long-necked sauropod squelched through the muck. Other dinosaurs crowded the setting. Several theropods - smaller cousins of the fearsome T. rex - may have been in pursuit of small, rodent-like creatures hopping about.

Within days, a flood covered the many footprints with rock, preserving them. Millennia passed, an asteroid struck, the continents shifted, sea levels fell, mammals rose, humans climbed down from trees and launched toward the stars. Finally, on a summer day in 2012, a self-taught fossil hunter named Ray Stanford noticed the unmistakable shape of the nodosaur's track as he drove out of a parking lot at what is now NASA's Goddard Space Flight Center in Greenbelt.


Years of excavation and analysis revealed the contours of that fossil print and dozens more on a single 10-foot-long slab of sandstone, Stanford and his colleagues announced Wednesday. It is the largest and most diverse assemblage from the dinosaur age found in the Mid-Atlantic region - and it ranks among the best fossil trackways in the world.

"I like to call it the Rosetta Stone," said Martin Lockley, a dinosaur track expert at the University of Colorado at Denver who participated in the research. The evidence on that slab surface preserves animals as they lived rather than as they died - revealing the ecology of their age in exquisite detail, he said.


And because no prints overlap, Lockley thinks the tracks were laid down and preserved in a "geologic instant" - no longer than a few days, but more likely during just a few hours. In such a contained setting, herbivore and carnivore, reptile and mammal, predator and prey all intersected and potentially interacted.

"One could literally make a movie about everything going on in this slab," said Stanford.

The retiree had no idea of the scale of his discovery when he stumbled upon the nodosaur footprint six years ago. He had come to Goddard to eat lunch with his wife, a NASA information specialist. He was heading home when he decided to take another look at an interesting bit of exposed sandstone stained brilliant red by large amounts of oxidized iron. Such rocks are ideal for preserving footprints, Stanford knew.

The scalloped impression of a nodosaur's four-toed foot validated his hunch, and a paleontologist from Johns Hopkins University confirmed the find.

But NASA was about to start construction on a new building in precisely that spot. Eager to get the fossil out of the way, the agency asked Compton Tucker - a climate scientist with experience using ground-penetrating radar - to survey the area and determine the extent of the sandstone. Then, over two chilly winter weekends, a cadre of volunteers from Goddard unearthed the whole hunk of rock.

At one point during the excavation, a NASA employee sheepishly confided that he walked past the outcrop every day without noticing what was embedded in it. "Look, you're an astrophysicist," Stanford recalls telling him. "Your mind is out there," he said, pointing to the sky. "I'm a dinosaur hunter. My mind is down here."

Stanford's keen attention to the ground beneath his feet is legend in the paleontology community. In a quarter-century of searching, he has tripled the number of dinosaurs and winged reptiles identified in Maryland. He discovered a nodosaur hatchling that is now on display at the Smithsonian and has filled his living room with so many fossils that his insurance company demanded he install extra supports to keep the house from collapsing beneath their weight.

But none of that, the 79-year-old Stanford maintains, can compare to his Goddard find: "It is more than I ever expected."

The excavated slab weighed more than four tons, so the space flight center arranged to have paleontologist Stephen Godfrey make a fiberglass cast that would be easier to study. The model was installed in Stanford's basement in fall 2015, where he would meticulously brush fine silt grains into the mold's dips and divots to reveal the prints. Then came hours of staring at the slab and attempting to divine what happened 110 million years ago from the faint impressions on its surface.

"I could not sleep," he recounted this week. "It was a time of total amazing discovery."

"Every time you came down and looked at it and turned the light at a different angle, you'd see something new," added his wife, Sheila, who often joined him in surveying the slab. Like her husband, she has no formal paleontology training. But she spotted some of the slab's more interesting features, including the impression of a winged pterosaur dipping its pointed jaw into the earth in search of food, then pushing off from the ground to take flight.

In all, the slab contains some 70 footprints from at least eight types of animal, the Stanfords and their colleagues report in an article published Wednesday in the journal Scientific Reports. Just one other discovery from the Mesozoic era (the 200 million-year span during which dinosaurs roamed the Earth) bears as many mammal prints.

The report highlights additional oddities: a dark, bulbous lump called a "coprolite," otherwise known as fossilized dinosaur poop, and a tubular structure that was probably the body of some prehistoric worm.

Two days before the find was to be announced, Stanford paid a visit to the fiberglass model, which Goddard installed on a wall in its Earth Science building. (The actual sandstone slab sits in a warehouse in Maryland.) Running his hand along its rugged surface, he pointed to a set of mammal prints.

"Our ancestors," he said. And then, "look how close his steps are." That proximity suggests the mammal was sitting on his haunches to search for food, much the way a squirrel might pose upright while nibbling a nut.

"They're foraging," Stanford said. He floated his hand over to the footprints of carnivorous theropods that appear nearby. "But someone else is foraging on them."

Looking with him, Tucker pointed out how the size, shape and spacing of the theropod tracks looked almost synchronized. "We think they could be hunting the mammals as a group," he said. "That shows some kind of social behavior."

Though the question of pack hunting among dinosaurs is still debated in the paleontology community, recent discoveries in Utah and China lend credibility to the theory.

The fiberglass cast will remain on display at Goddard for the foreseeable future. Its reception by NASA scientists depends on their background. Tucker, a climate researcher, looks at the fossils and considers whether the planet is headed toward a repeat of the Mesozoic, when high-atmospheric carbon dioxide levels heated the Earth. His colleague Melissa Trainer, who studies the environments on other planets, imagines a day when scientists uncover traces of life on alien worlds.

As for Stanford, he finds poetry in the fact that dinosaurs once walked the same landscape as astronomers and rocket scientists. Even in the Space Age, he said, the Earth "still has surprises."


Mansourasaurus shahinae: Egyptian Dinosaur Discovery Fires up Paleontology World, Shows Ties to Europe

Tuesday, January 30, 2018

The titanosaurian dinosaur Mansourasaurus shahinae is depicted in an artist's drawing. The dinosaur lived on the coast of what is now the western desert of Egypt approximately 80 million years ago. | REUTERS

A long-necked dinosaur unearthed in Egypt has yielded the first evidence of contact between African and European dinosaurs shortly before the creatures disappeared for good about 66 million years ago, scientists said Monday.

Given a dearth of dinosaur skeletons from Africa, paleontologists have battled to reconstruct a map of how the animals spread across the world after the “supercontinent” Pangaea broke up into different land masses some 200 million years ago.

Many believed Africa’s dinosaurs were completely isolated from cousins on other continents by the time their heyday was brought to an abrupt end, possibly by an asteroid strike.

The new specimen, an elephant-sized plant-eater given the name Mansourasaurus, sheds new light on Afro-European dinosaur ties, its discoverers said.

Looking at its physiology, the team concluded that Mansourasaurus was “more closely related to dinosaurs from Europe and Asia than it is to those found farther south in Africa or in South America,” according to a statement from Ohio University.

“This, in turn, shows that at least some dinosaurs could move between Africa and Europe near the end of these animals’ reign. Africa’s last dinosaurs weren’t completely isolated.”

Very few dinosaur fossils from the late Cretaceous period, about 100 to 66 million years ago, have been unearthed on the African continent.

Much of the land where fossils may be found is today covered in lush vegetation, unlike the exposed rock in which bones are frequently found in Patagonia, for example.

Discovered in the Sahara Desert, Mansourasaurus is the most complete dinosaur skeleton from the late Cretaceous ever found in Africa.

The remains include scattered bits of the creature’s vertebrae, skull, lower jaw, ribs, and leg bones.

Mansourasaurus is a titanosaur, a group that also included some of the biggest land animals ever to have lived, such as Argentinosaurus, Dreadnoughtus, and Patagotitan.

“When I first saw pics of the fossils, my jaw hit the floor,” said study co-author Matt Lamanna of the Carnegie Museum of Natural History.

“This was the Holy Grail — a well-preserved dinosaur from the end of the Age of Dinosaurs in Africa — that we paleontologists had been searching for for a long, long time.”


Source: AFP-JIJI,

Kootenayscolex barbarensis: Cambrian Period Worm Had Hair-Sized Bristles on Its Head and Body

Tuesday, January 30, 2018

Kootenayscolex barbarensis. Image credit: Danielle Dufault / Royal Ontario Museum.

 A new species of bristle worm that lived about 508 million years ago (Cambrian period) has been identified from fossils found in Marble Canyon and Burgess Shale sites, both in British Columbia, Canada.

Dubbed Kootenayscolex barbarensis, the ancient worm was a type of annelid, a highly diverse group of animals that includes modern-day leeches and earthworms.

“While the diversity of annelids in terms of their anatomies and lifestyles makes them ecologically important and an evolutionarily interesting group to study, it also makes it difficult to piece together what the ancestral annelid may have looked like,” said Karma Nanglu, a PhD candidate at the University of Toronto and a researcher at the Royal Ontario Museum.

Although annelids are found all over the world — from the bottoms of oceans and lakes to mountain glaciers — their early evolutionary history is confounded by a poor fossil record, with few species described from well-preserved body fossils near the evolutionary origins of the group.

“While isolated pieces of annelid jaws and some mineralized tubes secreted by the animals are well known, preservation of their soft tissues is exceedingly rare,” said Dr. Jean-Bernard Caron, also from the University of Toronto and the Royal Ontario Museum.

“You need to look to truly exceptional fossil deposits like those found in the Burgess Shale to find well-preserved body fossils. Even then, they’re quite uncommon and many of the currently described species there are still poorly understood.”

Kootenayscolex barbarensis had a pair of long sensory structures called palps on its head, with a small medial antenna between them. Its body was covered in fleshy appendages called parapodia which bear bristles called chaetae. These structures are used for movement. Image credit: Jean-Bernard Caron / Royal Ontario Museum.

Kootenayscolex barbarensis was up to 1.2 inches (3 cm) long and had hair-sized bristles on the head.

“The worm possessed paired bundles of hair-sized bristles spread along the body,” Nanglu said.

“This is one of the diagnostic features of this group of animals.”

“However, unlike any living forms, these bristles were also partially covering the head, more specifically surrounding the mouth.”

“The new species seems to suggest that the annelid head evolved from posterior body segments which had pair bundles of bristles, a hypothesis supported by the developmental biology of many modern annelid species.”

“The fine anatomical details preserved in Kootenayscolex barbarensis allow us to infer not only its evolutionary position, but also its lifestyle,” Nanglu added.

“Sediment preserved inside their guts suggests that, much as their relatives do in modern ecosystems, these worms served an important role in the food chain by recycling organic material from the sediment back to other animals that preyed on them.”

The findings are published in the January 22 edition of the journal Current Biology.


Karma Nanglu & Jean-Bernard Caron. 2018. A New Burgess Shale Polychaete and the Origin of the Annelid Head Revisited. Current Biology 28 (2): 319-326; doi: 10.1016/j.cub.2017.12.019


Scientists Discover 11th Archaeopteryx Fossil, the Oldest Yet

Saturday, January 27, 2018

The oldest specimen of Archaeopteryx was found in Germany. Photo by O. Rauhut/LMU


Mansourasaurus shahinae: School Bus-sized Dinosaur Fossil Found in Sahara Desert

Wednesday, January 31, 2018

The scientists recovered parts of its skull, lower jaw, neck and back vertebrae, ribs, shoulder and forelimb, back foot and osteoderms. (Image Source: Carnegie Museum of Natural History)

Researchers have found the fossil of a dinosaur in the Sahara Desert, which could help explain the evolution of the animals in the continent.

Scientists have unearthed in a Sahara Desert oasis in Egypt fossils of a long-necked, four-legged, school bus-sized dinosaur that lived roughly 80 million years ago, a discovery that sheds light on a mysterious time period in the history of dinosaurs in Africa.

Researchers said on Monday the plant-eating Cretaceous Period dinosaur, named Mansourasaurus shahinae, was nearly 33 feet (10 meters) long and weighed 5.5 tons (5,500 kg) and was a member of a group called titanosaurs that included Earth’s largest-ever land animals. Like many titanosaurs, Mansourasaurus boasted bony plates called osteoderms embedded in its skin.

Mansourasaurus, which lived near the shore of the ancient ocean that preceded the Mediterranean Sea, is one of the very few dinosaurs known from the last 15 million years of the Mesozoic Era, or age of dinosaurs, on mainland Africa. Madagascar had a separate geologic history.

Its remains, found at the Dakhla Oasis in central Egypt, are the most complete of any mainland African land vertebrate during an even larger time span, the roughly 30 million years before the dinosaur mass extinction 66 million years ago, said paleontologist Hesham Sallam of Egypt’s Mansoura University, who led the study published in the journal Nature Ecology and Evolution.

The scientists recovered parts of its skull, lower jaw, neck and back vertebrae, ribs, shoulder and forelimb, back foot and osteoderms. A lot of Africa is covered in grasslands, savannas and rain forests that obscure underlying rock where fossils may be found, said postdoctoral researcher Eric Gorscak of the Field Museum in Chicago, who was formerly at Ohio University.

While as massive as a bull African elephant, Mansourasaurus was modestly sized next to titanosaur cousins such as South America’s Argentinosaurus, Dreadnoughtus and Patagotitan and Africa’s Paralititan, some exceeding 100 feet (30 meters) long.

“Mansourasaurus, though a big animal by today’s standards, was a pipsqueak compared to some other titanosaurs,” said paleontologist Matt Lamanna of the Carnegie Museum of Natural History in Pittsburgh.

The researchers determined Mansourasaurus was more closely related to European and Asian titanosaurs than to those from elsewhere in Africa and other Southern Hemisphere land masses including South America formerly joined in a super-continent called Gondwana.

“This, in turn, demonstrates for the first time that at least some dinosaurs could move between North Africa and southern Europe at the end of the Mesozoic, and runs counter to long-standing hypotheses that have argued that Africa’s dinosaur faunas were isolated from others during this time,” Lamanna said.

By: Reuters