Category: Dinosaur and Prehistoric Animal News Stories

Aim to Keep “Dakota” in North Dakota

Hugely Important Duck-Billed Dinosaur Fossil Plans to Keep it in North Dakota

The permanent home for one of the most important dinosaur discoveries made in the last fifty years or so is under discussion in the United States.  The fossil, representing a duck-billed dinosaur that lived in the Late Cretaceous (Edmontosaurus regalis) has helped palaeontologists to learn a lot about these long extinct creatures as its state of preservation permitted large sections of the animal’s skin to be preserved along with ossified tendons, ligaments and even the possibility of having preserved internal organs.  Like many large specimens, the fossil has a nick-name, it is called “Dakota” as it was found in North Dakota back in 1999.  State officials in North Dakota are hoping that an agreement can be reached to permit the huge fossil to stay in the State, hopefully becoming a centre piece exhibit in a newly refurbished and expanded North Dakota Heritage Centre based in Bismarck (capital city of the State).  The Heritage Centre is due to re-open on November 2nd this year, the 125th anniversary of the State joining the United States of America.

A Close up of the Skin of the Edmontosaurus

Preserved skin on Late Cretaceous dinosaur fossil.

Preserved skin on Late Cretaceous dinosaur fossil.

Picture Credit: Associated Press

 To read more about the research into this remarkable dinosaur fossil: Dinosaur Fossil Begins to Show its Secrets

The Edmontosaurus died close to a river and the carcase was rapidly buried and a form of mummification took place, the fine grained sediments and the lack of oxygen when the body was buried prevented decay, hence the high degree of preservation.  The Edmontosaurus fossil was discovered by Tyler Lyson, on his uncle’s farm near the town of Marmarth.  The extraction and the preparation of the fossil was an enormous task.  The specimen was encased in two large blocks of stone, the largest of which weighed several tonnes.  The blocks were extensively scanned using sophisticated CT (computerised tomography) and even traces of organic compounds were identified in the matrix material.

Commenting on the importance and the significance of this fossil, North Dakota’s state palaeontologist John Hoganson said:

“We want to keep that iconic fossil in North Dakota.”

The fossil was prepared in the preparation laboratory at the Heritage Centre and it has been on exhibit in Bismarck, the State capital, but such is the importance of the fossil that it has been in demand from other museums and it was carefully packed up and sent over to Japan to take part in a major exhibition about Cretaceous dinosaurs before being returned to North Dakota.

A Model of an Edmontosaurus (E. regalis)

Edmontosaurus a member of the Hadrosaurine group of duck-billed dinosaurs.

Edmontosaurus a member of the Hadrosaurine group of duck-billed dinosaurs.

Picture Credit: Everything Dinosaur

The specimen is owned by Tyler Lyson, who since the fossil’s discovery has earned a doctorate in palaeontology from Yale University and is currently a post-doctoral researcher at the Smithsonian Institute.  Currently, Tyler is negotiating with the State Historical Society of North Dakota, sources suggest that the sum of money involved will be around $3 million USD to ensure the permanent future of this 76 million year old dinosaur.

Further research into “Dakota”: Dinosaur Mummy Reveals More Secrets

Tyler is reported to have said in a statement to the Associated Press:

“We are all working to keep Dakota at the North Dakota Heritage Centre and to establish a Marmarth Research Foundation endowment fund to be used to further vertebrate palaeontology.”

When the redeveloped Heritage Centre opens in November it will be a state-of-the-art museum and it would be fantastic to have “Dakota” as part of the dinosaur gallery.  It would also help with further study into this amazing specimen as keeping the fossil in a permanent home would help with fund raising efforts.  According to local sources, the finance to secure the fossil is not yet in place but it is likely that this iconic fossil will attract funding and significant sponsorship once arrangements for display have been put in place.

Dakota remains on loan to the Heritage Centre until 2015, all parties involved in the negotiations are keen to see the fossil stay in North Dakota and Everything Dinosaur team members are confident that there will be a swift resolution and that this fossil of a duck-billed dinosaur will remain in North Dakota.  Today, April 22nd is Earth Day, an annual event celebrated worldwide in which people demonstrate their support for environmental protection.  It is appropriate on this day of all days to be discussing the future of a dinosaur fossil, one that can tell scientists a lot about how these huge plant-eaters lived.

Ancient Shark Fossil Provides Insight into Jaw Evolution in Vertebrates

325 Million Year Old Fossil Suggests Sharks are Not “Primitive”

Often described as a group of animals that have remained virtually unchanged for millions of years, extant shark species (and there are something like 470 known species) are actually more highly evolved than previously thought.  The discovery of a remarkably well-preserved specimen of an ancient shark-like creature that once swam in a marine ecosystem more than 325 million years ago (Pennsylvanian Epoch of the Carboniferous), has provided palaeontologists with evidence to suggest that early cartilaginous and bony fishes have more to tell us about the evolution of jaws.

A study published in the academic journal “Nature”, vividly demonstrates how new fossil discoveries can dramatically alter our understanding of the evolution of vertebrates.  The fossil, a three-dimensional concretion, shows a combination of primitive and more advanced anatomical features in a cartilaginous fish, evidence of a sophisticated jaw has been identified along with a complete gill section.  Importantly, the fossil shows the arrangement of the jaw and the gills “in situ”, the fossil has preserved these delicate organs in their natural, life position.  The layout of these anatomical features are very similar to that found in bony fishes as well as cartilaginous fish.  This suggests that this specimen might represent a common ancestor of these extremely important vertebrates.

The Concretion that Represents the Fossilised Jaws and Gill Structures of a Palaeozoic Fish

Scale bar = 10 millimetres

Scale bar = 10 millimetres

Picture Credit: American Museum of Natural Hisotory/Pradel

The picture shows two lateral views (views from sideways on) of the fossil material that was later scanned at the European Synchrotron Radiation Facility to reveal its internal structures.

The first fish are believed to have evolved from Chordate animals (animals that possess a stiff rod that runs along or part-way along their body length for at least a portion of their life cycle).  The evolutionary links remain poorly known but fossils found in China indicate that the first jawless fish, (Agnathans) may have evolved more than 530  million years ago.  It is believed that sometime during the Silurian geological period, a crucial development in the history of life on Earth occurred, the first vertebrates with true jaws (Gnathostomes) evolved.  Although, this fossil, part of an enormous fossil collection donated to the American Museum of Natural History by Ohio University, may not represent the earliest jawed fish, its state of preservation has provided scientists with an insight into the evolution of jaws from modified gill arches.

The Evolution of Jaws in Fish (Agnathan compared to a Gnathostome)

How jaws may have evolved.

How jaws may have evolved.

In jawless fish (Agnathans), the first and second gill arches (branchial arches) support the first gill slit.  In jawed vertebrates, the first gill arch has become a pair of jaws and the first gill slit a spiracle to let water pass over the remaining gills.

Lead author of the research paper, post-doctoral researcher at the New York based museum, Alan Pradel stated:

“Sharks are traditionally thought to be one of the most primitive surviving jawed vertebrates.  Most textbooks in schools today say that the internal jaw structures of modern sharks should look very similar to those in primitive shark-like fishes, but we’ve found that’s not the case.  The modern shark condition is very specialised, very derived and not primitive.”

The story of this significant breakthrough, starts with Ohio University professors Royal and Gene Mapes and their students, who over the years amassed in excess of half a million Palaeozoic fossils from Arkansas, Oklahoma and Texas.  The fossils represent marine ecosystems and consist of invertebrates such as Trilobites, Ammonites, Brachiopods and Gastropods, as well as a number of fossils of primitive fish.  The fossilised skull of the new species named Ozarcus mapesae  is so well preserved it allowed scientists to create a three-dimensional model to show the organisation of the jaw in relation to the gill arches.  The trivial name for this new species honours the Ohio University professors.

Fish heads, including cartilaginous fish such as sharks and rays, are segmented into the jaws and a series of arches that support both the jaw and the gills.  However, as the fossils of most early Gnathostomes (jawed fish) are poorly preserved and usually distorted and flattened, this is the oldest known specimen found to date that shows the jaw/gill arch relationship in such clarity.

A Computer Generated Image that shows the Internal Structures of the Fossil

3-D image of fossil produced.

3-D image of fossil produced.

Picture Credit: American Museum of Natural History/Pradel

The picture above shows one of the three-dimensional images created after the fossil material had been bombarded with X-rays to produce the computer model.  The brain case can be seen at the top (shaded a tan colour), the structure of the jaws are shaded red, the jaws having evolved from the first gill arch.  The second gill arch, known as the hyoid arch is shown in blue.  The remaining gill arches are shaded yellow.

Commenting on the importance of this donated specimen, one of the study authors, John Maisey (American Museum of Natural History) added:

This beautiful fossil offers one of the first complete looks at all of the gill arches and associated structures in an early shark.  There are other shark fossils like this in existence, but this is the oldest one in which you can see everything.   There is enough depth in this fossil to allow us to scan it and digitally dissect out the cartilage skeleton.”

In order to study the three-dimensional concretion so the layout and the orientation of the delicate branchial arches (gill arches) could be mapped, the scientists took the specimen to the European Synchrotron Radiation Facility (ESRF), located at Grenoble in France so that high-resolution X-rays could bombard the specimen and produce a detailed, computer generated image of the fossil in three-dimensions.  The team discovered that the arrangement of gill arches is not like that seen in modern, extant sharks.  Instead the gill layout is fundamentally similar to that seen in bony fishes (Osteichthyans).

The authors state that it is not unexpected that sharks, because of their long evolutionary history, would undergo evolution of these anatomical structures, but bony fish may have more to tell us about the first jawed ancestors of land-living vertebrates such as ourselves than living sharks.  Bony fish are the most successful group of Gnathostomes.  All Tetrapods (that includes us) are descended from bony fish.

Sharks – A very Diverse and Geographically Widespread Group

Sharks - a diverse group with over 470 extant species.

Sharks – a diverse group with over 470 extant species.

Picture Credit: Everything Dinosaur

Ichthyosaur Fossil Discovered at Lyme Regis

New Ichthyosaur Fossil Discovery at Lyme Regis

Yesterday, team members at Everything Dinosaur received news that a beautifully preserved Ichthyosaur specimen had been discovered at Lyme Regis.  Our chum Brandon, a local fossil expert from Dorset, sent us some pictures and a video which illustrate the exciting discovery.   The specimen was discovered on the beach to the east of the town of Lyme Regis, near to where the council have been working to strengthen the cliff area and to improve the town’s coastal defences.

Video Footage of the Ichthyosaur Discovery

Video Credit: Brandon Lennon

 The video shows the block which contains the fossil specimen, vertebrae can be clearly seen along with some of the rib bones, the skull is only partially exposed.  The dig team will cut the block away from the surrounding material and carefully transport the specimen away so that it can be prepared and examined in detail.  From the video, the bones don’t look too compressed or deformed and although some of the distal elements of the skeleton are probably missing, this particular Ichthyosaur looks relatively complete.  It is a little difficult to get our bearings just from the video and the photographs that we have received but we think the specimen was discovered in the Blue Lias of the Church Cliffs section of beach, immediately east of Lyme Regis.

The Location of the Fossil Discovery

The location of the fossil find.

The location of the fossil find.

Picture Credit: Brandon Lennon

Water is carefully removed from around the fossil matrix, sand bags will be put in position to help keep the fossil material protected and then the dig team will map the exposed bones and work out the best way to cut and remove the stone block.

The Fossil Material is Carefully Examined

Icthyosaur fossil find April 2014.

Ichthyosaur fossil find April 2014.

Picture Credit: Brandon Lennon

Carefully the specimen is exposed and then the layout and orientation of the fossil material is studied.  Consideration needs to be given to the tide times as the specimen will be covered once the tide turns.

A Close up of the Ichthyosaur Fossil

The vertebrae can be clearly made out.

The vertebrae can be clearly made out.

Picture Credit: Brandon Lennon

The hand in the photograph helps to provide scale.  The Ichthyosaur is lying with its head facing towards the bottom right and the tail up towards the top left of the photograph.  The vertebrae can be clearly seen in the picture.  It is certainly a member of the Ichthyosauria Order, but it is very difficult to assign a species name to the specimen at this stage just having the short video and the photographs to study.  As a guess, it might be an example of Ichthyosaurus breviceps, however, it is best to wait until the fossil material has been more thoroughly prepared before any precise identification can be made.

The Ichthyosauria were an Order of fast-swimming, nektonic and (as far as we know entirely marine), predatory marine reptiles with dolphin-shaped bodies.  As a group, these highly specialised reptiles evolved in the Early Triassic and thrived throughout the Jurassic and for much of the Cretaceous, before finally becoming extinct around 80 million years ago.

An Illustration of a Typical Jurassic Ichthyosaur

Dolphin-like prehistoric animals.

Dolphin-like prehistoric animals.

Lyme Regis is an amazing place to visit and a fossil hunting trip to the beach is highly recommended, although we at Everything Dinosaur would advise that you take advantage of the local knowledge of a fossil hunting expert so that you can get the most from your visit.

To read more about guided fossil walks: Guided Fossil Walks (Lyme Regis)

We look forward to hearing more about this exciting fossil find and no doubt there will be more marine reptile discoveries made over the next few months.

The Weird and the Wonderful – Chinese Triassic Marine Reptiles

Parahupehsuchus longus – Armoured Marine Reptile with a “Corset”

As life on Earth recovered from the devastating End Permian mass extinction event which took place some 250 million years ago, it seems that a myriad of strange and bizarre vertebrates evolved to take advantage of vacant niches in ecosystems that had arisen due to the extinction of so many different types of organism.  One of the strangest marine creatures known to science has just been described in the on line scientific journal PLOS One.  It seems that as environments and ecosystems recovered in the Early Triassic, so marine Tetrapods evolving the capability to eat other marine Tetrapods came about in earnest and the first Tetrapod apex predators of the sea appeared.  This led to the evolution of body armour and other forms of protection in smaller marine Tetrapods that were now the potential prey.  Step forward the bizarre Parahupehsuchus longus, around a metre long, marine reptile that evolved a bony tube that completely surrounded its body wall, like a sort of armoured corset.  Just like a corset, breathing movements and body movements may have been restricted, but the primary role for this unusual pseudo carapace was probably protection against attacks from a much larger predatory marine reptile that shared P. longus’s watery world.

Back in 2011, scientists from the Wuhan Centre of China Geological Survey undertook a field excavation in Yuan’an County, Hubei Province, (east central China), to find Early Triassic marine reptile fossils.  The strata in this part of China represents exposures of marine sediments laid down in a shallow tropical sea around 248 million years ago (Jialingjiang Formation).  The area had been mapped and studied since the late 1950′s and a number of marine reptile genera unique to this part of the world had already been named and described.  However, when Chinese scientists first studied these fossil rich deposits, the strata was believed to be younger, dated to the Anisian faunal stage of the Middle Triassic.  The rocks at this location were thought to be roughly the same age as Triassic marine strata found in the provinces of Yunnan and Guizhou (south-western China).  More recent studies have assigned the sediments exposed around Yuan’an County to be up to three million years older than most of the sedimentary rocks bearing marine reptile fossils in Yunnan and Guizhou.  The rocks which entombed Parahupehsuchus longus date to around 248 million years ago (Olenikian faunal stage of the Lower Triassic).  This is significant because the vertebrate fossils found in Yuan’an County are much closer to the End Permian extinction event than those from south-western China, the ecosystem represented is one that is at an earlier stage of recovery from the most devastating extinction event known.

Parahupehsuchus longus (Holotype Material WGSC 26005)

Scale bar = 10cm

Scale bar = 10cm

Picture Credit: PLOS One

In the diagram above the strange bony carapace-like structure surrounding the body of this new species of marine reptile can be clearly made out.  The labels in red have been added by Everything Dinosaur to help readers gain a better understanding as to the layout of the fossil as the skull and much of the tail is missing.

The research team identified more than ten marine reptile specimens, one partially complete fossil represents this new genus.  Most of the marine reptile specimens discovered represented animals of around a metre in length, but one fossil suggests a marine reptile of around 4 metres in length.  Although not formally described yet, the skull is robust and the teeth that of a meat-eater.  It has been suggested that this reptile was the apex predator.  Parahupehsuchus evolved its corset-like body to resist attacks from this much larger marine reptile.  Surprisingly, very few fish fossils have been found in the strata that contains the marine reptile fossils.  This might be a reflection of fossil preservation bias, but if there were few fish species present and this may not be that surprising as something like 57% of all marine families died out at the end of the Permian, it seems that marine reptiles evolved to attack and hunt other marine reptiles.  The corset of Parahupehsuchus may have evolved as a response to the predatory pressure.

Parahupehsuchus has been assigned to the Hupehsuchia Order of marine reptiles.  This Order currently consists of just three genera, all of which are found in the Lower Triassic sediments of Hubei Province.  The first named and described was Nanchangosaurus, then in 1972 a near complete specimen of a new type of marine reptile that had been discovered was named this was Hupehsuchus.  Palaeontologists consider that Parahupehsuchus was closely related to Hupehsuchus.

Parahupehsuchus pronounced “par-rah-hoop-pay-sook-cus” means beside Hupehsuchus which refers to the taxonomic relationship between these two genera.  The term Hupehsuchus is derived from Hupeh, an alternative spelling for Hubei Province and the Greek word for crocodile.

Hupehsuchus nanchangensis  Fossil Material (specimen number WGSC 26004)

Scale bar = 10cm

Scale bar = 10cm

 Picture Credit: PLOS One

The more complete specimen (diagram B) above, provides scientists with clues to how Parahupehsuchus might have looked.  It may have had a long narrow, toothless snout like its close relative Hupehsuchus.  It was probably capable of moving around on land as well as being adapted to a marine environment and although the tail is missing in the holotype specimen it is likely that the tail was quite powerful and Parahupehsuchus propelled itself through the water with sideways movements of its tail, in a similar to modern Crocodilians today.

If indeed Parahupehsuchus had a toothless jaw, then it may have eaten soft-bodied creatures such as squid.  This bizarre marine reptile remains unique amongst vertebrates for the strange configuration of its trunk.  Its body is completely surrounded by a bony tube, around fifty centimetres long and nearly seven centimetres deep.  The tube is made up of overlapping ribs and gastralia (belly ribs).  This tube and the presence of dermal armour on the dorsal surface of the skeleton (back) have been interpreted as defensive features to withstand the bites of larger marine reptiles.  This is evidence that by the Early Triassic, ecosystems had recovered enough from the End Permian extinction event to permit the establishment of complex marine Tetrapod food chains dominated by large apex vertebrate predators.

The Front Dorsal Region of Parahupehsuchus longus

White scale bar shown on actual fossil material = 1cm

White scale bar shown on actual fossil material = 1cm

Picture Credit: PLOS One

The unique corset-like body protection is made up of a combination of fused true ribs, belly ribs (gastralia) and neural spines.

Key

red = dermal armour, scales and ossicles (da)

dark brown = first segment of neural spine (ns1)

dark green = second segment of neural spine (ns2)

grey = ribs (ri)

orange = lateral gastralia (lg)

white = median gastralia (mg)

green = bones of the left forelimb

arf (pink) = anterior rib facet extending from the parapophysis, dia (light brown) = diapophysis of the neural arch, para (yellow) = parapophysis main facet.

Note that ribs and gastralia overlap in a complex manner and the double rib articulation prevents rib motion.  This would have made chest movements difficult for breathing and restricted the body movements to aid swimming and locomotion on land.

Although, the ribs are expanded in a similar way to that of a turtle’s shell, Parahupehsuchus is not closely related to the Chelonia (turtles, tortoises and terrapins).  This might be an example of convergent evolution.

Scientists hope to find more fossils of this strange marine reptile in rocks that make up the Jialingjiang Formation and with further research they intend to build up a more detailed picture of the food chain that is represented by this Lower Triassic fossil material.

Huge Extraterrestrial Impact that Shaped Our World

Impact Earth 3.26 Billion Years Ago

Scientists have discovered tell-tale signs in the geology of Earth which reveal a catastrophic ancient impact event that would have dwarfed the dinosaur killing asteroid of sixty-five million years ago.  Approximately, 3.26 billion years ago, the region we now know as South Africa was hit by a colossal rock from space, a rock that would have been at least three times the size of the space rock responsible for the Cretaceous impact event.  Such was the magnitude of the impact that the Earth’s crust shifted, giving rise to some of the tectonic features that are still found today.

The study, published in the academic journal “Geochemistry, Geophysics, Geosystems” focuses on the geological formation called the Barberton greenstone belt in South Africa.  This formation can be found in the north-east of South Africa and it partially borders the sovereign state of Swaziland.  The rocks are mainly continental and consist of some of the oldest continental crust rocks known.  The research team examined the seismology of the region and they estimate that between 3.47 billion and 3.23 billion years ago the area was the site of a massive impact from outer space.

Huge Extraterrestrial Object Crashes into Earth Around 3.26 Billion Years Ago

Cataclysmic impact event.

Cataclysmic impact event.

Picture Credit: Don Davis commissioned by NASA

During that time in the formation of the Earth and the solar system, our planet had cooled sufficiently for oceans to form and primitive bacterial thrived, although at the time there was very little oxygen, the most significant gases in the atmosphere were nitrogen and carbon dioxide.  The impact event occurred after the “Late Heavy Bombardment – LHB” which was a period of several hundred million years ending around 3.7 billion years ago when the inner rocky planets and satellites of the solar system was bombarded by space debris, left over from the creation of the planets and other bodies that make up our solar system.  The space rock, perhaps an asteroid or even a comet from further out in the solar system crashed into Earth. The object measured between 37 and 58 kilometres across and smashed into the region of southern Africa at a speed of more than 20 kilometres a second (a speed of around 43,000 miles an hour).  The crater caused would have measured over five hundred kilometres in diameter (300 miles), although this has been eroded away.  The resulting impact sent seismic waves through the entire planet and it is likely that these seismic waves exceeded the amplitudes of typical earthquake waves. The duration of extreme shaking was also far longer, probably hundreds of seconds, than that from strong earthquakes.  Debris thrown up into the atmosphere would have sufficient momentum to leave the Earth’s orbit, firestorms would have ravaged the planet and tsunamis hundreds of metres high would have smashed into the nascent continents.  Indeed, water at the surface of the oceans would have been boiled away.  Such was the force generated that subduction might have occurred as a result, helping to shape the continents.

Geologist, Donald Lowe of Stanford University and a co-author of the scientific study explained:

“We can’t go to the impact sites.  In order to better understand how big it was and its effect we need studies like this. We knew it [the impact event] was big, but we didn’t know how big.”

The Earth and the primitive life upon it would have been devastated, wiping out whole genera of bacteria, but just like the extinction event that marks the end of the Cretaceous, other organisms would have evolved to replace those that had died out, just as the Mammalia rose to prominence with the extinction of the Dinosauria.  The shock of the impact could also have moved the tectonic systems around the Earth’s crust into a higher gear, making the planet more tectonically active.  The impact of this event, so long ago, is still being felt by the Earth today the researchers speculate.  Identified by the presence of spherule beds in the Barberton greenstone belt, this Archean impact event has shaped the way the Earth’s continents and oceans came about.

The Size and Scale of the Impact

Impact event in the Barberton greenstone belt of South Africa.

Impact event in the Barberton greenstone belt of South Africa.

Picture Credit: American Geophysical Union

The illustration above compares the extraterrestrial object responsible for the Chicxulub impact that may have helped wipe out the dinosaurs, with the Archaen impact event and the world’s highest mountain, Mount Everest.  The impact craters illustrated are compared with the island of Hawaii for scale.  The estimated crater formed by the collision around 3.26 billion years ago may have been as much as five hundred kilometres across.

Commenting on the research, geologist Frank Kyte of the UCLA (University of California, Los Angeles) stated:

“This is providing significant support for the idea that the impact may have been responsible for this major shift in tectonics.”

Bizarre New Triassic Marine Reptile Described

Atopodentatus unicus from Yunnan Province

The fossils of a bizarre marine reptile with a unique mouth have been discovered in south-western China.  Although its body resembles other types of marine reptile, the skull and the mouth are extremely unusual and nothing like them has been seen before in the fossil record.   A number of scientists have speculated about this strange anatomical arrangement, the upper jaw resembles a vertical slit with fine teeth arranged to form sieve-like structure. A prehistoric animal that has a “zipper” for an upper jaw.   These adaptations indicate that this three-metre long sea creature evolved to fit a very specialist niche in the marine ecosystem of 245 million years ago.

The animal has been named Atopodentatus unicus, the name translates from the Latin to mean “peculiar teeth of unique shape” and one glance at an illustration of this particular beastie shows why the nomenclature is so appropriate.

An Illustration of A. unicus

Strange Triassic marine reptile.

Strange Triassic marine reptile.

Picture Credit: Nobu Tamura 2014

This is one of those occasions when the interpretation of the fossil material and a resulting illustration needs to proceed any further discussion so that the reader can gain an impression of just how weird this animal was.

The land that makes up the border between the south-western Chinese provinces of Guizhou and Yunnan is very important to palaeontologists as they try to reconstruct how life on Earth bounced back following the End Permian mass extinction.  The rocks laid down in this region represent Early and Middle Triassic marine faunas, the fine sediments that were deposited at the bottom of a shallow, tropical sea have preserved a wealth of marine reptile fossils, along with fishes and a vast array of invertebrates.  By recording the diversity of life preserved within this series, scientists can see how life on Earth recovered from the mass extinction event that marked the end of the Permian geological period.  The Atopodentatus fossil material was found in  Luoping County (Yunnan Province), the strata in this area has been dated to around 245 million years ago (Anisian faunal stage of the Middle Triassic), a little over five million years since the extinction event that saw an estimated 95% of life on the planet wiped out.  At this time in the Triassic, a number of different types of marine reptile had evolved, all of which were descended from terrestrial ancestors.

A large number of Ichthyosaur specimens have been discovered, some Ichthyosaurs co-existed with Atopodentatus but in younger Triassic rocks (Ladinian to Carnian faunal stages 230 to 225 million years ago), it seems that Ichthyosaurs has established themselves as the largest and most important marine reptile group.  The other types of marine reptile that lived alongside Atopodentatus are almost as bizarre.  There are primitive Sauropterygians, such as Nothosaurs and animals that are ancestors of the much more familiar Plesiosaurs and Pliosaurs, Protorosaurs, partially marine reptiles that were to give rise to the long-necked Tanystropheus and other peculiar Archosauriforms.  It seems that this part of the world was a “melting pot” for marine reptile evolution with some groups, surviving into the Jurassic, with other types completely dying out within a few million years.

A Specimen of the Sauropterygian Nothosaur called Keichousaurus

Keichousaur Fossil

 These rocks have been explored and mapped for more than ten years, by an international team of scientists. The report on the strange Atopodentatus has been published in the academic journal “Naturwissenschaften”, the study into A. unicus was conducted by scientists from the Canadian Museum of Nature, the Wuhan Institute of Geology and Mineral Resources as well as the Chinese Academy of Sciences.

Dr Xiao-Chun Wu (Canadian Museum of Nature) and his colleagues named the new prehistoric creature Atopodentatus unicus and suggest it belonged to a Superorder of reptiles called the Sauropterygians.  Staff from Everything Dinosaur, having reviewed the fossil bones have suggested it might be a type of Nothosaur, but one with a very specialised feeding method.  The body of the animal was quite long, the neck short and the skull much deeper than other similar sized Triassic marine creatures.  Most Nothosaurs were fish-eaters, but the dentition and the morphology of the jaws suggest that this newly discovered reptile had a weak bite and teeth unsuitable for tackling struggling prey.

On each side of the mouth, A. unicus had around 35 small, pointed teeth in the front of the upper jaw.  There were around 140 similarly shaped teeth in the rest of the upper jaw, with at least 100 located in the horizontal portion  with reminder located in the vertical, zipper-like portion of the top jaw.  There were nearly 200 teeth located in the lower jaw, over half of which were in the horizontal portion with the reminder located in the shovel-headed front part. All the teeth were covered in enamel, indicating even wear across all parts of the crown of the tooth, but the teeth do not look very worn, perhaps this hints at the sort of prey this animal specialised in catching.  Whatever it was eating, it probably had this food resource all to itself amongst the vertebrates as no other creature found to date has anything approaching the jaw anatomy of this marine reptile.

The Prepared Fossils (Atopodentatus unicus)

Bizarre Triassic marine reptile.

Bizarre Triassic marine reptile.

Picture Credit: Long Cheng/Wuhan Institute of Geology and Mineral Resources

The picture shows the long, serpentine body of the reptile with the deep, shovel-shaped skull shown as an inset.  Note the well developed limbs, particularly the large humerus.  This prehistoric animal was probably only partially marine, still capable of venturing out onto land, although the broad wrist bones and elongated fingers and toes enabled the limbs to be used to help the animal swim.

As to what this animal actually ate, no one knows for sure, there is nothing similar living today that seems to have anything remotely like its specialised feeding apparatus, or is there?  The Bowhead Whale (Balaena mysticetus), has plates of baleen made from keratin in its mouth which it uses to sieve out planktonic organisms as it swims through Arctic waters.  The mouth of Atopodentatus may have been adapted for sieving out small creatures but not from open water like the huge-mouthed Bowhead, but from soft mud on the sea floor.  Dr. Wu and his colleagues, suggest that the broad, shovel-like head of this marine reptile may have ploughed through soft sediments with its teeth sieving out soft-bodied creatures such as marine worms.

The doctor added:

“It is obvious that such delicate teeth are not strong enough to catch prey, but were probably used as a barrier to filter micro-organisms or benthic invertebrates such as sea worms.  These were collected by the specialised jaws, which may have functioned as a shovel or push-dozer and a grasper or scratcher.”

At the moment, the actual function of the jaws remain a mystery.  Perhaps a specimen will be found with stomach contents preserved or perhaps some trace fossils will be discovered the reveal a ploughed up seabed.  One of the few certainties surrounding this bizarre creature is that like a number of the strange marine reptiles that existed in the Mid Triassic seas of China, within a few million years this particular branch of the marine family tree had become extinct.

Call for more Work to be Done on Western Australia’s Dinosaur Trails

Research being Carried out on the Dampier Peninsula Dinosaur Tracks

Usually when team members at Everything Dinosaur are asked to write about Australian dinosaur research, the focus is on sites in Queensland or indeed Victoria, however, a series of extensive dinosaur tracks located in Western Australia, along the Dampier peninsula north of the small town of Broome, are rapidly coming to prominence.  In the Early Cretaceous, around 130 million years ago (Barremian faunal stage), Australia was much further south than it is today, it was not a separate continent but attached to the landmass that would become Antarctica.  Coal deposits and plant fossils indicate that the climate at this southerly latitude was much warmer than it is today, there was probably no permanent ice at the poles and the land that was to become Western Australia was a huge flood plain, crossed by large, slow moving rivers.  Dinosaurs flourished in this environment and evidence of the diversity of the dinosaurs has been preserved in a multitude of dinosaur tracks.  The trackways can be found all along the coast north of Broome, where the Lower Cretaceous Broome sandstone is exposed.  The lengths of the tracks are very significant, some of the trackways can be correlated over a tens of metres, they are regarded as “mega track sites”, otherwise known colloquially as “dinosaur freeways”.

Tridactyl Theropod Tracks from the Broome Area

Three-toed dinosaur tracks.

Three-toed dinosaur tracks.

Picture Credit: Government of Western Australia (Dept. of State Development)

In a survey undertaken in 2011 a number of dinosaur trackways were classified and assessed, something in the region of fifteen different types of dinosaur have been identified including Sauropods, Ornithopods, Theropods and armoured dinosaurs (Thyreophora).

Dr. Steve Salisbury (University of Queensland), one of the researchers who carried out the study in 2011 is keen to see further research work undertaken and is enthusiastic about making the dinosaur tracks and trails better known to the public.  However, it is important that any studies are undertaken with the utmost respect for the feelings of the local indigenous people as the tracks and footprints play an important role in local aboriginal art and culture.  Dr. Salisbury commented on the importance of these Cretaceous dinosaur footprints:

“There are some really important ones, scientifically and culturally, that we don’t really want to let everyone know where they are.  But there are plenty of tracks that it would be fantastic to share them with people… Broome should embrace what it’s got on its doorsteps because it’s really special.”

In addition, care should be taken when it comes to publicising the location of some of the tracks, thefts of dinosaur footprints have occurred and in 1996 prints made by an armoured dinosaur were stolen from the Crab Creek area on the north coast of Roebuck Bay.  The theft of dinosaur fossils, even trace fossils such as footprints is an all too often occurrence, to read an article about the theft of a dinosaur footprint from Jurassic aged strata near to the town of Moab in Utah: Dinosaur Footprint Stolen in Utah.

Some of the Sauropod prints (long-necked dinosaurs) are huge.  Individual prints have been measured at over 1.7 metres long.  Although ichnologists (the term used to describe a person who studies trace fossils), are not able to assign a genus to the footprints, it has been estimated that some of the Sauropod dinosaurs that made the tracks were in excess of thirty metres in length.

Giant Sauropod Trackways from Western Australia

Dinosaur tracks from the Broome area of Western Australia.

Dinosaur tracks from the Broome area of Western Australia.

Picture Credit: Government of Western Australia (Dept. of State Development)

The enormous, rounded prints of a Sauropod dinosaur can be clearly seen in this picture taken in the Red Cliffs area.

The scientists hope that their studies will help shed more light on the ecology of this part of the world in the Early Cretaceous.  The large number of different dinosaur species that the tracks potentially represent gives the palaeontologists the opportunity to learn a little more about the behaviour and interactions of the Dinosauria.  The team intend to digitally map the locations using technology similar to that used recently to recreate the famous Sauropod/Theropod tracks preserved in the Paluxy River of Texas.

To read more about the Paluxy River trace fossils: Digitally Mapping a Famous Set of Dinosaur Tracks

Dr. Salisbury explained what the dinosaur footprints and tracks showed:

“Some of them look like they’re on a mission; they’re definitely heading somewhere.  Other ones look like they’re lost, and they’re wandering around in circles… We’ve got a record of what they were doing and it’s a hundred and thirty million years old, so it’s pretty special.  If you could go back in time and look at the Broome area, you would have seen all these different types of dinosaurs wandering around; it would have been really special. It’s your own Cretaceous Park, on your doorstep.”

The tracks are sacred to the local indigenous people.  The Aborigine tribes in the area believe that the tracks help explain their creation story and the scientists are keen to record the fossils, take latex rubber copies of the prints but to leave all the tracks in situ.  The first recorded description of a print made by non-indigenous people dates back to the 1930′s but the entire region has not been fully studied to date.  The survey undertaken in 2011 highlighted the importance and the significance of the location, now scientists are hoping to learn more by walking in the footsteps of dinosaurs.

Earliest Cardiovascular System Described from Chinese Cambrian Arthropod

Oldest Known Cardiovascular System Identified – Fuxianhuia protensa

The fossil of an Arthropod found in rocks laid down around 520 million years ago with an exquisitely preserved cardiovascular system has been described by a team of scientists led by researchers from the Natural History Museum in London.  The specimen represents the oldest known fossil showing a rudimentary heart and blood vessels known to science.  Thanks to remarkable fossil sites such as the Burgess Shale deposits in British Columbia and beautifully preserved remains of Cambrian creatures from highly fossiliferous strata from south-western China, palaeontologists have built up an astonishing amount of data on life in the seas and oceans of the world around 520 to 500 million years ago, a period in the geological history of planet Earth known as the Cambrian explosion due to the range and diversity of organisms that had evolved at that time.

The exquisitely preserved specimen represents Fuxianhuia protensa from the Middle Cambrian aged strata of the Chengjiang Formation (the Moatianshan shales of Yunnan Province, south-west China).  Fossils of this shrimp-like creature are very common in these marine shales, sixteen different phyla that have been identified from the Chengjiang Formation, a location that rivals the Burgess Shales in terms of the rich fossil record that has been preserved, although the material from the Chengjiang Formation is slightly older than the fossils from the Walcott Quarry section of the Burgess Shale deposits.  Until this particular specimen had been studied, it has been assumed that most of the internal organs of early Arthropods would not survive the fossilisation process.  Some fossils had been found that indicated the presence of a digestive tract and back in October 2013, Everything Dinosaur reported the discovery of an Arthropod (Alalcomenaeus spp.) from the same region of Yunnan Province that showed signs of a brain and the soft tissue preservation of a nervous system, here we report on the discovery and mapping of a complete cardiovascular system in a 520 million year old Arthropod.

To read more about this earlier discovery: Ancient Arthropod Brain and Nervous System Studied

Although many fossils of F. protensa are known, its taxonomic position with the Arthropoda remains unclear, it is thought to be a basal member of this phyla, which today is the largest phylum of animals and includes crustaceans, insects, spiders, mites, scorpions, centipedes, king crabs millipedes and a number of extinct Orders such as the Trilobita.  The external skeleton is most commonly preserved, either as parts shed as the animal grew or as complete specimens that represent animals that died, however, due to the exquisite degree of preservation in some specimens from the Chengjiang Formation, scientists now have a much better understanding of the internal anatomy of early Arthropods.  What is remarkable, is that sophisticated cardiovascular and nervous systems seem to have evolved in the Arthropoda at an early stage in the history of life on Earth.

Fuxianhuia Fossils that have been used in the Study

Cardiovascular system in 520 million year old Arthropod preserved.

Cardiovascular system in 520 million year old Arthropod preserved.

Picture Credit: Journal of Nature Communications

The photograph shows examples of the F. protensa fossil material used in the study.  Diagram (a) is a view of specimen YKLP 11336 from above (dorsal view), the location of the digestive tract running down the centre of the body is indicated by the black arrows.

Illustration (b) shows the head and the front of the animal (anterior view), specimen number YKLP 11337, the white arrows indicate the mouth of the creature.  Part (c) shows the filled gut within the abdominal segments, the gut has been preserved as carbon in this specimen (YKLP 11338).  Diagram (d) shows empty gut area marked by arrows in abdominal segments Ab9 to Ab14.

Diagram (e) shows the preserved outline of the cardiovascular system (YKLP 11335), A1 in the photograph marks the position of the left antenna and ey marks the position of the right eye.  The black triangles towards the top of the picture indicate the position of the bottom portion of the animal’s headshield.  The white outlined triangles towards the bottom of photograph (e) show the end of the thorax portion of the animal’s body.

Scale Bars

Most complete specimens of F. protensa are around 30 mm in length, the scale bars in the photographs are:

(a) = 5 mm

(b, c and d) = 1 mm

(e) = 4 mm

Commenting on the significance of this fossil discovery, palaeontologist Xiaoya Ma (Natural History Museum, London), one of the authors of the scientific paper published in the journal “Nature Communications” stated:

“It is an extremely rare and unusual case that such a delicate organ system can be preserved in one of the oldest fossils and in exquisite detail.  However, under very exceptional circumstances, soft tissue and anatomical organ systems can be preserved as fossils.”

Scientists now have an excellent understanding of the internal organisation of the anatomy of this Arthropod.  Usually, soft tissue decays rapidly after death and fossils typically only preserve the hard parts of an organism, such as the exoskeleton in the case of the Arthropoda.  With Fuxianhuia protensa the fossils show a tubular heart in the middle of the body with a complex system of blood vessels leading to the creature’s antennae, eyes, brain and limbs.  The cardiovascular system consists of the heart and the blood vessels.  It allows blood to circulate and to deliver oxygen and nutrients around the body.  Most higher forms of life in the Kingdom Animalia have such a system, although those organisms without a real body cavity such as flatworms and jellyfish do not.

The specimens studied suggest that as early as 520 million years ago, Arthropods had evolved a complex internal anatomy which is very similar in structure to the internal anatomy found today in extant Arthropods such as shrimps.

Like the Burgess Shales, the Chengjiang Formation material has preserved much of an ecosystem that thrived in a shallow marine environment more than half a billion years ago.  It seems that these two ancient environments suffered much the same fate as each other even though just like today, in the Cambrian, these two locations were thousands of miles apart.  Both the Burgess Shale Formation and the Chengjiang Formations represent shallow marine environments which were on slopes.  From time to time mudflows, buried entire ecosystems and as a result, a wealth of organic material has been preserved.  A large number of Fuxianhuia fossil material is known from Yunnan Province, scientists believe that this Arthropod was benthic (living on the sea floor), although it is not known whether this animal was an active hunter or a scavenger.

A Schematic Diagram of the Internal Anatomy of Fuxianhuia protensa

Digestive tract and cardiovascular system of Fuxianhuia protensa

Digestive tract and cardiovascular system of Fuxianhuia protensa

Picture Credit: Journal of Nature Communications

The diagram above shows the internal anatomy of F. protensa.  Diagram (a) shows the cardiovascular system (red) shown in relation to the brain and central nervous system (blue).  Diagram (b) shows the whole reconstruction, with brain and segmental ganglia (blue) overlaid against the external skeleton of the animal.  Diagram (c) shows the cardiovascular system in relation to the digestive tract (green).  In all three diagrams, the tubular heart organ can be seen running down the central region of the thorax.

Thanks to highly detailed fossils from British Columbia and south-western China, scientists have been able to acquire a lot of knowledge about life in the oceans of the world during the Cambrian geological period.  Although, advanced and highly evolved cardiovascular systems were present in many organisms, the paucity of the fossil record that pre-dates the Cambrian prevents scientists from calculating when key structures such as hearts and brains first evolved.  Given the degree of sophistication seen in the Fuxianhuia material two competing theories have been put forward.  Firstly, such specialised internal structures such as hearts, brains and a cardiovascular system must have evolved gradually with incremental changes many millions of years before the Cambrian.  Secondly, the evolution of such specialised internal organs occurred relatively quickly in response to the development of predator/prey interactions and the increased availability of food resources.

The research team are able to conclude that organisms had cardiovascular systems before Fuxianhuia, but evidence of lacking in the fossil record so no further light on the subject can be cast for the time being.

The genus name Fuxianhuia is after Lake Fuxian in Yunnan Province, the specific or trivial name “protensa” means “elongated” a reference to the elongated thorax of the creature.

Digitally Reconstructing a Famous Dinosaur Trackway

Dinosaur Tracks Lost to Science for Decades Recreated Using Digital Technology

A set of dinosaur tracks, one from a large Sauropod dinosaur, the second set from a meat-eating dinosaur, have been digitally recreated permitting scientists to study the complete tracks for the first time in more than seventy years.  The footprints, which cover a distance of approximately forty-five metres, are part of a number of dinosaur trackways preserved in near marine sediments that were laid down between 113 and 110 million  years ago (Cretaceous geological period).  The Theropod dinosaur’s three-toed prints overlie the larger Sauropod prints and this indicates that the large herbivorous dinosaur passed first, perhaps the carnivore was stalking the Sauropod.  The tracks, now forming part of the bed of the Paluxy River in Texas are often referred to as the “dinosaur chase tracks”, although scientists cannot be certain whether or not the Theropod was stalking its prey.

The Famous Dinosaur “Chase” Tracks (Paluxy River, Texas)

Famous dinosaur tracks - Theropod and Sauropod tracks.

Famous dinosaur tracks – Theropod and Sauropod tracks.

Picture Credit: Everything Dinosaur

The picture above shows a potential interpretation of the Paluxy River tracks, with the huge, plant-eating dinosaur being stalked by the bipedal, Theropod dinosaur.  It is difficult to assign a genus to these dinosaur footprints, but it has been speculated that the Theropod may have been a member of the Acrocanthosaurus genus, as fossils of this large predator have been found in similar aged rocks and a dinosaur bone from the Glen Rose Formation, has been assigned to Acrocanthosaurus.

Using a technique called photogrammetry, scanning and combining photographs taken during research at the location back in the 1940′s, the scientists were able to build a digital model of the site.  The computer model created is the only complete record available to study as some of the physical tracks themselves have been lost.

The Paluxy River dinosaur tracksite is among the most famous in the world.  In 1940, Dr. Roland T. Bird, a American palaeontologist from the American Museum of Natural History (New York), described and excavated a portion of the site containing associated Theropod and Sauropod trackways, the so-called “dinosaur chase tracks.  As the river flow was in danger of completely eroding away the dinosaur footprints, it was decided to remove the tracks in a serious of carefully excavated blocks.  The trackway was thus broken up into a number of sections.  Split up as it was, the fossil specimens were housed in different museum collections and over the years the slabs have deteriorated and a portion of the track has been lost.

The research team, which included scientists from Liverpool University, the Royal Veterinary College (London) and Indiana-Purdue University, Indiana, applied state-of-the-art photogrammetric techniques to seventeen black and white photographs of the tracks that had been taken by Dr. Bird during the 1940 trace fossil study.  By producing highly detailed scans of the original photographs and their corresponding negatives the researchers were able to digitally reconstruct the site prior to its fateful excavation.  Furthermore, the three-dimensional study was able to corroborate sketches drawn by Dr. Bird when the trackway was first scientifically described.

Sixteen of the Photographs from the 1940 Expedition Used to make the 3-D Digital Map

Some of the original photographs used to create the 3-D image.

Some of the original photographs used to create the 3-D image.

Picture Credit: PLOS One

This new mapping technique demonstrates the exciting potential for digitally recreating palaeontological, geological, or archaeological specimens that have been lost to science, but for which photographic documentation still exists.

Using dinosaur footprints made back in the Aptian/Albian faunal stage of the Cretaceous, this work has dramatically illustrated the potential for the technique of historical photogrammetry, permitting the creation of highly detailed and precise 3-D maps of sites that may have been physically lost and just preserved in photographs.  In this instance, the last time the set of dinosaur tracks was complete was back in 1940 prior to the removal of the footprint blocks.

A Digital View of the Reconstructed Tracks

Video Credit: PLOS One

Commenting on the significance of this study, lead researcher Dr Peter Falkingham (Royal Veterinary College) stated:

“Here we’re showing that you can do this to lost or damaged specimens or even entire sites if you have photographs taken at the time.  That means we can reconstruct digitally, and 3-D print, objects that no longer exist.”

The World’s Most Northerly Dinosaurs

Duck-Billed Dinosaur Bone from Axel Heiberg Island

Much has been discovered about the northern ranges of Late Cretaceous dinosaurs over the last two decades or so.  Palaeontologists now recognise that during the last few million years of the Cretaceous geological period a number of different dinosaur genera adapted to living at high latitudes, year round residents of territory which today is well within the Arctic Circle.  There have been a number of important fossils finds at locations such as those from the Prince Creek Formation (North Slope Borough, Alaska), only recently a new genus of pygmy Tyrannosaur was scientifically described – Nanuqsaurus hoglundi.

To read more about this new Tyrannosaur: The “Polar Bear” Tyrannosaur

Although the climate was much milder, the weather at these very high latitudes would have been seasonally extreme.  There would have been long periods of total darkness with the sun never ascending over the horizon with snow falls and temperatures close to or below freezing for prolonged periods.  In the summer, the high latitude would have have guaranteed twenty-fours of daylight for a number of weeks and the overall climate, based on studies of plant fossils and pollen suggests an environment similar to the state of Oregon in the United States or perhaps British Columbia (Canada).  The fossils found in the Prince Creek Formation are certainly important, but they do not represent the most northern dinosaur discovery to date.  That honours goes to a single, fossil bone found during a geological survey of the remote Axel Heiberg Island in 1992.  Axel Heiberg Island is seventy-nine degrees north and is one of the larger islands of the Canadian Arctic Archipelago.  It is uninhabited, although some research teams set up seasonal summer camps.

The highly abraided dinosaur bone was determined as being a Hadrosaurine veretebra (back bone), although the genus remains uncertain.  It was found in the Kanguk Formation which consists of marine strata laid down during the Late Cretaceous.  A number of other vertebrate fossils have also been found but to date only one dinosaur bone.  It is likely that this fossil was deposited during the Campanian faunal stage of the Late Cretaceous (around 83 – 74 million years ago).

During the Campanian, the eastern Canadian Arctic was likely isolated both from western North America by the Western Interior Seaway and from more southern regions of eastern North America by the Hudson Seaway.  This fossil suggests that large-bodied Hadrosaurid dinosaurs may have inhabited a substantial polar insular landmass during the Late Cretaceous, where they would have lived year-round.  Being effectively marooned on the land mass, these dinosaurs were unable to migrate southwards  to escape the worst of the winter weather.  It is possible that the resident herbivorous dinosaurs could have fed on non-deciduous conifers, as well as other woody twigs and stems, during the long, dark winter months when most deciduous plant species had lost their leaves and others would have died back due to the lack of sunlight.

It is likely that other dinosaur fossil discoveries await on the islands that make up the Canadian Arctic Archipelago, however, the difficulty in reaching them, the extreme climate and the lack of a road network or suitable airstrip means that much more research has been carried out in Alaska than on the islands of the high Arctic.  Palaeontologists are confident that further research will establish a rich and diverse Late Cretaceous ecosystem that was dominated by dinosaurs.

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