Kunbarrasaurus ieversi – Sheep-sized Armoured Dinosaur from Australia

Australia has its newest dinosaur.  Kunbarrasaurus has been identified from fossil remains formerly described as Minmi paravertebra following an in-depth, three-dimensional analysis of the skull.  This sheep-sized armoured dinosaur roamed what was to become Queensland around 100 million years ago.

A New Armoured Dinosaur from Australia Kunbarrasaurus

The fossil material, including a very well preserved skull was discovered in 1989 and assigned to the genus Minmi, however, extensive analysis of the fossil began in 2007 and the specimen was subjected to extensive CT scanning and three-dimensional modelling to reconstruct the palate, braincase, inner ear and nasal cavities.  The research team found that this basal member of the clade Ankylosauria was sufficient different from Minmi to warrant setting up in its own genus.

An Illustration of the Lightly Armoured Kunbarrasaurus (K. ieversi)

Kunbarrasaurus ieversi of the Cretaceous (Australia).

Picture credit: University of Queensland/Australian Geographic

The fossil which is partially articulated, was found eroding out of the mudstone rock exposed at Marathon Station, near Richmond (north-western Queensland).  The strata which makes up the Allaru Formation from which the specimen was excavated, represents a shallow, low energy marine environment.  It is likely that the corpse of this two-metre-long dinosaur was washed out to sea.  Or perhaps this dinosaur was washed out to sea and drowned, either way, its carcase sank and settled on the seabed and it was quickly buried providing excellent conditions for fossilisation and fossil preservation.

The Fossilised Remains of Kunbarrasaurus

The skull is to the left of the photograph.

Picture credit: University of Queensland

Significant Ankylosaur Discovery

The fossils, part of the Queensland Museum collection, represent the most complete dinosaur fossil found to date from eastern Gondwana (Antarctica, India, New Zealand and Australia).  In addition, it is the most complete ankylosaurian fossil known from that ancient, southern super-continent.  The cranial material (skull) is exceptional.  It is one of the few skulls associated with the Ankylosauria clade in which the sutures have not fused or been obliterated by the presence of heavy, dermal armour or the remodelling of bone.

The name Kunbarrasaurus (pronounced koon-bah-rah-sore-us)  means “shield lizard” in the local Mayi language of the indigenous Wunumara people from this part of Queensland.  The species name honours Mr Ian Ievers, the property manager at Marathon Station who discovered the fossil.

Commenting on the study, lead researcher Lucy Leahey, a PhD student at Queensland University stated:

“Ankylosaurs were a group of four-legged, herbivorous dinosaurs, closely related to stegosaurs.  Like crocodiles, they had bones in their skin and are commonly referred to as ‘armoured’ dinosaurs.”  When it was first studied back in the 1990s, the fossil was placed it in the same genus as Australia’s only other named Ankylosaur, Minmi, which is based on some bones from Roma in south-western Queensland.”

Computerised Tomography Yields Clues to Identity

Although a total of seven fossil specimens had been assigned to the genus Minmi, only two had been studied in detail.  In collaboration with scientists from the Denver Museum of Nature and Science the specimen was subjected to a detailed CT scan and from this Professor Lawrence Witmer (Ohio University) was able to reconstruct a complex, three-dimensional model of the skull, the nasal cavities and the inner ear.

Three Dimensional Cranial Osteology Study of Kunbarrasaurus

3-D Map of skull material.

Picture credit: University of Queensland

Kunbarrasaurus

Professor Witmer added:

“The CT reconstruction revealed that Kunbarrasaurus had a more complicated airway than other dinosaurs, but less so than ankylosaurs from the Northern Hemisphere.  The inner ear is proportionately enormous and unlike anything we have seen before in a dinosaur.”

Explaining that the inner ear configuration resembles that seen in a Tuatura or a turtle the scientists remain puzzled as to this complicated structures purpose.

One of the paper’s authors Dr Steve Salisbury (Queensland University) stated that the team did not know why the inner ear was shaped in this way.  In addition, the nasal (airway) passages in the skull were also very sophisticated, but not as those seen in more derived, later ankylosaurs found in North America.  These airways could have helped to give this plant-eating dinosaur a powerful sense of smell, or they may have helped keep the brain cool.

For the moment, Kunbarrasaurus has been classified as basal member of the Ankylosauria clade, Dr Salisbury said:

“It [Kunbarrasaurus] appears to represent an early, less heavily armoured member of the group, close to the point at which the Ankylosaurs diverged from the other main lineage of armoured dinosaurs, the Stegosaurs.”

A Single Fossilised Footprint

A single fossilised footprint found in south-eastern Queensland indicates that there may have been at least one type of Stegosaur that lived in this part of the world during the Middle Jurassic.  A spokesperson from Everything Dinosaur commented:

“There is some tantalising evidence to suggest that a number of different types of thyreophoran dinosaur existed in what was to become Queensland during the Jurassic and into the Early Cretaceous.  Tracks and footprints have been recorded from a number of locations and from a number of different aged strata but body fossils are exceptionally rare.  Kunbarrasaurus is only the second armoured dinosaur to be named from Australia.”

For replicas and models of armoured dinosaurs and prehistoric animals: PNSO Age of Dinosaurs Replicas.

Researchers Discovery Mineralised Blood Vessels in 80 Million-Year-Old Dinosaur

Stories of dinosaur soft tissue discoveries are becoming relatively common.  The unprecedented power of some of the very latest analytical tools are provided palaeontologists and other researchers with remarkable insights into the lives of the Dinosauria and other extinct creatures.  Once upon a time, the concept of a “dinosaur biologist” was just a pipe dream, but being able to study the biology of non-avian dinosaurs is becoming a distinct possibility.

American scientists including researchers from North Carolina State University and the University of Texas (Austin, Texas) have published details of the discovery of mineralised blood vessels preserved within the fossils of a duck-billed dinosaur – Brachylophosaurus canadensis.

A paper detailing the research “Timothy P. Cleland et al. Mass Spectrometry and Antibody-Based Characterization of Blood Vessels from Brachylophosaurus canadensis”, has just been published in the “Journal of Proteome Research”.

Blood Vessels from the Demineralised Fossilised Bones of a Duck-billed Dinosaur (B. canadensis)

Analysis strongly suggests that these are blood vessels.

Picture credit: Mary Schweitzer, North Carolina State University

Dinosaur Blood

Mary Schweitzer, one of the authors of the paper, is a leading authority on the identification of potential soft tissue remains in the fossils of extinct species.  In 2007, she was one of a group of scientists that published a paper detailing the discovery of soft tissue remains within the sixty-eight-million-year-old fossilised femur of a Hell Creek tyrannosaur.  Dr Schweitzer, formerly based in Montana is the Research Curator (palaeontology) at the North Carolina Museum of Sciences, part of North Carolina State University.

To read two articles related to the Dr Schweitzer’s research: The Hunt for Dinosaur DNA and also: Ancient Mosquito Fossil with its Victim’s Blood.

The leader of the research, Dr Tim Cleland (University of Texas) commented:

“This study is the first direct analysis of blood vessels from an extinct organism and provides us with an opportunity to understand what kinds of proteins and tissues can persist and how they change during fossilisation.”

Brachylophosaurus canadensis – Contribution to the Advancement of Science

Thanks to the extensive fossil material associated with this Late Cretaceous hadrosaur, scientists have been able to gain a great deal of information about this particular member of the Dinosauria.  For example, a superbly well-preserved specimen allowed palaeontologists to identify dinosaur stomach contents, other specimens have contributed to our understanding of the radiation and evolution of duck-billed dinosaurs and in 2009, a team of American researchers found evidence of proteins in the femur of a Brachylophosaurus: Dinosaur Femur Reveals Dinosaur Proteins.

An Illustration of the Duck-billed Dinosaur Brachylophosaurus canadensis

Brachylophosaurus illustrated.

Picture credit: Houston Museum of Natural Science

Structures Resembling Blood Vessels

Structures which resembled blood vessels have been recovered before from fossil dinosaur bones after removal of the mineral material (demineralisation).  In this study, the research team set about testing these structures to see if they were likely to be endogenous to the bone (belonging to Brachylophosaurus) or whether such structures were the result of bacteria colonising the empty spaces in the bone after the original organic components had rotted away.

Using high-resolution mass spectrometry and an immunofluorescence study the scientists found two lines of evidence to support the idea that these structures did originate from the dinosaur and that they represent components of the blood vascular system.  Firstly, peptide sequencing of the extracts from the bone proved to be consistent with peptides from extant archosaurian blood vessels (ostrich and chickens).  Secondly, proteins identified by the mass spectrometry assessment could be localised to the tissues using antibodies specific to these proteins.

One of the proteins identified was myosin, it is found in the smooth muscles associated with the lining of blood vessels.  The scientists report that:

“When all data are taken into consideration, the most parsimonious explanation is that these vessels, derived from demineralised dinosaur bone, are endogenous.”

Outlining the implications for this research, Dr Cleland explained:

“This will provide new avenues for pursuing questions regarding the evolutionary relationships of extinct organisms, and will identify significant protein modifications and when they might have arisen in these lineages.”

Visit Everything Dinosaur’s website: Everything Dinosaur.

New Pterosaur Genus Discovered in Utah

Much excitement was generated at the annual Society of Vertebrate Palaeontology conference in Dallas (Texas), when Brooks Britt, an Associate Professor of Geology at Brigham Young University (Utah) updated the audience on a remarkable fossil discovery from north-eastern Utah, close to the State border with Colorado.  During the Late Triassic, the western part of North America was covered in vast sand dunes.  The area resembled the Sahara of today.  Just like in the Sahara, there were pockets of life clustered around water sources.

Associate Professor Britt and his colleagues have for some years now been excavating the fossilised remains of fauna that lived around an oasis approximately 210 million years ago.  For these residents, surrounded by the desert, their collective luck ran out when during a severe drought the water evaporated and much of this ancient ecosystem was wiped out.  The bad luck of the Triassic animals is good fortune for palaeontologists as they have been able to piece together a remarkable picture of the fauna of this Late Triassic oasis.

Triassic Pterosaur

One of the most impressive discoveries made so far, came in 2014.  The quarry known as the Saints and Sinners Quarry had been explored for more than a decade.  The beds that make up the quarry are fossiliferous as they represent lake shoreline sediments, rocks laid down at an oasis that was surrounded by vast desert dunes.  Brigham Young University student Scott Meek unearthed from the sandstone the partial remains of a pterosaur.

Pterosaur fossils from the Late Triassic and Early Jurassic are rare in North America.  The specimen has yet to be formally described and named but it does represent a new species (most likely a member of the Dimorphodontidae family or possibly ancestral to this pterosaur family).

An Concept Drawing of the New Late Triassic Pterosaur from Utah

Four-fanged hunter of the oasis.

Picture credit: Josh Cotton

Although not large when compared to later members of the Pterosauria, the Utah specimen had a wingspan of around 1.3 metres, making it about the size of a modern day European Herring Gull (Larus argentatus).  It had a large head and a jaw lined with over one hundred pointed teeth (110 in total).

Fangs on a Triassic Pterosaur

Four of the teeth, located towards the front of the lower jaw were more like fangs.  The largest of them measures 2.5 centimetres long.  This is one pterosaur that would have looked very mean indeed!  The orbits (eye-sockets) are smaller than seen in other members of the Dimorphodontidae family, perhaps as this flying reptile lived in a very bright and sunlit environment with lots of glare from the surface of the lake and the surrounding desert it may have evolved smaller eyes to help protect its vision from the excessive bright light, although this is only speculation on our part and we await with interest the scientific paper on the pterosaur specimen that will probably be published next year.

A Triassic Oasis – Teeming with Life

Associate Professor Britt specialises in studying sediments.  These sediments help to build up a picture of the climate and the environment at the time.  These sandstones have also revealed what happened to the animals that depended on the oasis and why the fossil assemblage came to be formed, Brooks Britt explained:

“The animals likely died during a severe drought, and the sediments indicate their carcasses were buried when the rains returned to normal and the lake filled, with the lapping waves burying the bones with sand.”

The fossil is also relatively three-dimensional.  Most pterosaur fossil bones are easily crushed and distorted.  Associate Professor Britt added:

“Outside of a find in Greenland, this is the first good Triassic pterosaur from North America.”

The scientists also found a wealth of other vertebrate fossils, including at least twenty individual Coelophysoid theropod specimens, plus the teeth of a much more substantial meat-eating dinosaur.  In addition, cursorial crocodylomorph fossils (the victim in the pterosaur illustration), along with evidence of sphenosuchians and a drepanosaurid, a representative of a bizarre group of Late Triassic reptiles that may have been arboreal, were discovered.

Why Didn’t the Pterosaur Fly Away?

All the other vertebrate fossils found at the dig site are from entirely terrestrial animals.  These animals would have been effectively trapped by the desert and not capable of travelling the distance required to find a new habitat when the oasis began to dry up, but why didn’t the pterosaur just fly away?  Perhaps other pterosaurs were able to leave and this fossil represents an old or sick individual.

Or alternatively, the shape of the pterosaur’s wings may provide a clue.  The wings of this creature are relatively short and broad, suggesting that they were not adapted to long distance flight.

These wings are more suited to short flights with the need to dodge and to weave, perhaps round obstacles such as trees.  This new pterosaur may have been an agile flier well suited to a life hunting in the trees close to the lake, but once the lake dried up, it may not have been capable of travelling the large distance required in order to find a new home.

We look forward to reading more about the “Saints and Sinners” pterosaur in 2016.

For scale models of pterosaurs and other prehistoric animals: CollectA Deluxe Scale Prehistoric Animal Models.

North America’s Newest Pterosaur – Cimoliopterus dunni

A new species of fish-eating, toothy flying reptile has been named and described from a partial rostrum found by an amateur fossil hunter in Texas.  This new Texas pterosaur named Cimliopterus dunni is the second in the Cimliopterus genus, the first, now named Cimliopterus cuvieri is known from fossil material found close to Maidstone in Kent (southern England).  This newly described Texan pterosaur links Texas to England according to the author of the scientific paper just published in the academic journal the “Journal of Vertebrate Paleontology”, Dr Timothy S. Myers.

The Fossilised Rostrum (beak) of the New Texan Pterosaur

Texas pterosaur had an English cousin.

Picture credit: Hillsman Jackson, Southern Methodist University

In the picture above, the Texas fossil specimen, found in 2013 is compared against the illustrations made of the 1851 Maidstone fossil find.

Small Fossil = Big Problems

Both the English 1851 pterosaur fossil (found in a chalk pit near Maidstone, Kent) and the Texas material belong to the family of pterosaurs called the Ornithocheiridae, a diverse and globally distributed pterosaur family.  They have both been assigned to the genus Cimoliopterus, however, the English fossil material was known by several other names before finally being assigned a genus of its own back in 2013, coincidently the same year as the Texas rostrum was found, as prolific amateur fossil collector Brent Dunn was exploring the spillway of Lake Lewisville, north of Dallas.

Many of the pterosaur fossils found in southern England and assigned to the Ornithocheiridae are extremely fragmentary.  During the latter half of the 19th century some of the leading scientists of the time, Owen, Seeley and Hooley studied the very worn and poorly preserved pterosaur fossils excavated from the upper Cretaceous chalk deposits of southern England.  Between name they named a number of genera, most of which were based on mere scraps of fossils with very few if any clearly defined autapomorphies (distinctive anatomical features).

Assigned to the Pterodactylus Genus

When first described, the Maidstone specimen was assigned to the Pterodactylus genus, over the years this assessment fell out of favour and various other names were erected.  Richard Owen for example, re-named this specimen as Coloborhynchus cuvieri.  Further revisions followed, just two years ago the specimen was assigned its own genus and named Cimliopterus cuvieri (Rodrigues and Kellner).  The genus name means “chalk wing”, the species name in this case honours the French scientist and anatomist Georges Cuvier.  The Texas trivial name honours the fossil finder – Brent Dunn who sadly passed away a few months after his discovery.

As both the English and American fossils were found in marine sediments, biostratigraphical dating has been carried out.  These fossils date from the Cretaceous, from around 94 million years ago, a time when the Atlantic was beginning to open up and North America was splitting away from Europe as the super continent of Laursaia broke up.

Pterosaur Relatives from Two Diverging Landmasses

Closely related flying reptile species one from the southern United States and one from southern England suggests that these reptiles moved between North America and England earlier in the Cretaceous, despite the gradual widening of the nascent Atlantic Ocean, a process that is on-going today.  They are different species so some evolutionary divergence must have occurred, in essence two groups of the same species became separated and gradually over time they took slightly different evolutionary paths resulting in two distinct species being found in the fossil record.

Commenting on his research, Dr Myers (Research Curator, Shuler Museum of Palaeontology, Southern Methodist University) stated:

“The Atlantic opened the super-continent Pangaea like a zipper, separating continents and leaving animal populations isolated, so gene flow ceased and we start to see evolutionary divergence.  Animals start to look different and you see different species on one continent versus another.  Pterosaurs are a little trickier because unlike land animals they can fly and disperse across bodies of water.  The later ones are pretty good flyers.”

A Typical Member of the Ornithocheiridae (Guidraco from China)

Model has an articulated jaw.

Picture credit: Everything Dinosaur

The picture above shows a typical member of the Ornithocheiridae pterosaur family.  As a group they are noted for their dentition (teeth), the long and pointed fangs of these creatures were particularly well suited to catching fish.  Most of the fossils of ornithocheirids are associated with marine deposits, so it has been suggested that these pterosaurs were accomplished fliers able to soar effortlessly over the sea rather like some species of sea bird do today.

The CollectA Deluxe model range contains a number of scale models of iconic pterosaurs: CollectA Deluxe Prehistoric Life Models.

The Lack of Toothy Pterosaur Fossils from North America

The fossil record to date shows that toothed pterosaurs are generally abundant during the Cretaceous in Europe, Asia and South America, but the fossils of this type of flying reptile are exceedingly rare in North America.

The new Texas native, Cimoliopterus dunni, is only the third toothed pterosaur species from the Cretaceous of North America.   All three of the toothy Cretaceous-era pterosaurs discovered so far from North America were found in the “Lone Star” State.   Even so, Cimoliopterus dunni is most closely related to England’s Cimoliopterus cuvieri and not to the other two genus of Texan toothy pterosaur so far named (Aetodactylus halli, also named by Dr Myers (2010) and Uktenadactylus wadleighi* which was named in 1994).

Texan Pterosaurs

Despite all three Texan toothed pterosaurs being assigned to the Ornithocheiridae family, the two other pterosaurs are associated with older strata.  In the case of Uktenadactylus*, these fossil remains are associated with rocks at least ten million years older than the marine shale deposits where the rostrum of Cimoliopterus dunni was found.

To read Everything Dinosaur’s article on the discovery of Aetodactylus: The Expanding Ornithocheiridae, say hello to “Eagle Finger” of Texas.

Ironically, Uktenadactylus also has a very close relative known from England – Coloborhynchus clavirostris known from the Albian age Cambridge Greensand deposits which underlie many of the chalk formations to be found in England.

Dr Myers explained:

“Given the small sample size, it’s odd that we have two that are so closely related to the English species.  It’s hard to draw any statistically significant conclusions from that, but it definitely indicates this is not a one-off, and that there was some relatively strong, significant connection.  Two means a lot more than one in this case.”

Dr Myers is not hypothesising about a land bridge connecting these two continents, although sea levels may have fluctuated over time resulting in these types of pterosaur indulging in a bit of “island hopping” only for the sea levels to rise again, isolating groups of these flying reptiles which led to the speciation.

The Bizarre Global Distribution of the Toothed Pterosaurs

Despite the identification of a third species of toothy Pterosaur from Texas, the mystery of why there is so little evidence to tie in North American and South American Pterosauria remains.

Dr Myers added:

“There are toothed Pteranodontoids in South America, lots of individuals and lots of different species, but no close relatives to the toothed Pteranodontoids in North America.  That might indicate there was some barrier to dispersal from the south.  It’s unusual we don’t see a connection between these pterosaur populations.  Maybe we will when we find more of this material.”

The quest to find more toothed pterosaur specimens can catch even the most dedicated and experienced palaeontologist out.  Back in January 2011, Everything Dinosaur reported on the naming of a new genus of toothed pterosaur identified from a partial jaw discovered in Canada.  The pterosaur was named Gwawinapterus beardi.  However, subsequent analysis revealed that the fossil specimen was more likely to have come from a prehistoric predatory fish.

To read about the Canadian discovery: New Pterosaur with Teeth Like a Piranha.

Gwawinapterus Unravelled: Mistake in Naming Flying Reptile.

*Formerly known as Coloborhynchus wadleighi.

Ceratopsians from Appalachia

A serendipitous discovery made by Dr Nick Longrich (University of Bath), whilst exploring the fossil collection of the Yale Peabody Museum (New Haven, Connecticut) has helped to provide a tantalising glimpse into the Late Cretaceous dinosaur fauna of North America.

Fragment of Jawbone from North America

The fragment of upper jawbone (maxilla) has been identified as coming from a early member of the horned dinosaur family and it reinforces the idea that thanks to the Western Interior Seaway, the dinosaurs on the eastern part of the landmass that we now know as North America were very different and genetically diverging from the dinosaurs living on the western part of the continent.

Although to the casual observer the fossil specimen looks like a mere scrap of fossil bone, this is the first evidence of a horned dinosaur found in eastern North America.

An Artists Impression of What the Dog-sized Dinosaur Would Have Looked Like

First fossil evidence of Ceratopsians in eastern North America.

Picture credit: Nicholas Longrich/University of Bath

A Dog-sized Dinosaur

Described as being about the size of a Labrador dog, Dr Longrich has not been able to assign a genus to his fossil find.  However, this does represent a new species, one that is difficult to name given the lack of fossil material.

Dr Longrich (from the Milner Centre for Evolution, part of the Department of Biology and Biochemistry at Bath University), was examining some of fossils held in the collection of the Peabody Museum at Yale University when he noticed the jaw fragment.  It had been found on a farm in North Carolina in 1985 and labelled as a maxilla from a duck-billed dinosaur.

Intrigued by the bizarre shape of the bone and not being able to place the maxilla within any hadrosaurid genus that was familiar to him, Dr Longrich decided to study this fragment in greater detail.

Views of the Maxilla Identified as Ceratopsian

Various views, dorsal, lateral, ventral etc.

Picture credit: Nicholas Longrich/University of Bath

Although the fossil bone was only around four centimetres in length, Nicholas was able to compare this fragment of upper jaw with other ornithischian dinosaurs and the short teeth sockets, the tooth socket arrangement in the jaw and their shape and the way that the toothrow curved led him to assign this fossil to the Leptoceratopsidae family.

Introducing the Leptoceratopsids

The Leptoceratopsidae are a family of ceratopsids known from fossil finds from Asia and North America, although some fragmentary fossils from Sweden and Australia have been assigned by some authors to this family.  They are characterised by their small size (less than three metres long), presence of a neck frill but no horns other than pronounced jugal bones.  They may have been facultative bipeds, mostly walking on all fours but with the ability to walk or run on their hind legs should the need have arisen.

Regarded as basal ceratopsians, this is a bit of a misnomer as the group persisted until the very end of the age of dinosaurs with a number of species living alongside the giant quadrupeds such as the better known horned dinosaurs such as Styracosaurus, Triceratops and Centrosaurus.

The number of genera in this family has been swelled in recent years due to a number of new fossil discoveries such as Zhuchengceratops from China and Gryphoceratops and Unescoceratops from southern Alberta (Canada).

A Unique Slender and Down-turned Toothrow

The maxilla has some unique autapomorphies (unique anatomical characteristics).  It is long, narrow and down-curved, this suggested a specialised feeding strategy.  What exactly this little herbivorous dinosaur fed on is open to speculation but during the time when it lived (around 77 million years ago), the flowering plants were rapidly evolving.  Perhaps, it evolved to feed on a certain group of plants that represented the undergrowth of forests and woodlands.

A Dinosaur from a “Lost Continent”

During the later stages of the Cretaceous, rising sea levels cut the continent of North America in two.  In the east, the long spit of land called Laramidia existed and thanks to the wealth of fossil finds from Alberta, Utah and Montana a great deal is known about the dinosaur fauna that roamed the eastern part of the divided landmass.

The fauna of the eastern part, called Appalachia, is not well known in comparison.  Fossil discoveries have been few and far between, much of the Cretaceous-aged fossil bearing material has been eroded away and not a great deal of sedimentary, fossil-bearing strata is exposed in the eastern part of the United States when compared to the vast open spaces of the west.

The Continent of North America During the Late Cretaceous

Lots of information known about Laramidia ceratopsids but this is the first fossil ceratopsid bone identified from Appalachia.

Picture credit: University of Bath

The leptoceratopsid fragment fits into a larger pattern of dinosaur evolution.  It does not resemble any of the Leptoceratopsidae genera known from Laramidia.  This suggests that as the landmass of Appalachia became more and more isolated, genetic divergence occurred with the isolated dinosaur species evolving different forms from their cousins in the west.

For models and replicas of North American dinosaurs and other prehistoric animals: Wild Safari Prehistoric World Models and Replicas.

Asian Dinosaurs in North America?

Many of the dinosaurs from Laramidia resemble Asian dinosaurs more closely than those identified from Appalachia.  Tyrannosaurus rex for example, had an Asian cousin Tarbosaurus bataar.  There is also a close resemblance in hadrosaur faunas.  From time to time as sea levels rose, the northern tip of Laramidia was able to connect with Asia, a land-bridge was formed and this enabled periods of fauna exchange between the continents to occur.  However, Appalachia remained an island for much of the Late Cretaceous and this permitted a largely unique dinosaur fauna to evolve.

Dr Longrich’s paper on the Leptoceratopsidae maxilla has been published in the academic journal “Cretaceous Research”.  Thanks to his keen eyesight whilst exploring the Peabody Museum, the Late Cretaceous dinosaur fauna of eastern North America is well and truly in the spotlight.

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