All about dinosaurs, fossils and prehistoric animals by Everything Dinosaur team members.
/Dinosaur and Prehistoric Animal News Stories

Fossil finds, new dinosaur discoveries, news and views from the world of palaeontology and other Earth sciences.

22 05, 2019

Fossilised Mouse Reveals Evolutionary Secrets of Colour

By | May 22nd, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Ancient Mouse Reveals a Colourful Mammalian Heritage

Many mammals are brightly coloured, we have golden marmosets, red pandas and of course, black and white zebras.  The evolutionary use of colour within the Kingdom Animalia has long held the fascination of scientists, academics and philosophers.  This week, an international team of researchers led by members of The University of Manchester have published a new study revealing the evidence of colourful pigments in the remains of a prehistoric mouse.

The Fossilised Remains of a Prehistoric Mouse

The fossilised remains of a mouse.

The well-preserved remains of a Pliocene mouse used in the study.

Picture Credit: The University of Manchester

Writing in the journal “Nature Communications”, this work marks a major breakthrough in our ability to define colour pigments within the fossilised remains of long extinct animals and emphasises the role colour plays in the evolution of life on our planet.  The paper entitled “Pheomelanin pigment remnants mapped in fossils of an extinct mammal”, outlines the use of X-ray imaging on the 3 million-year-old fossils in order to unravel the story of key pigments in ancient creatures and demonstrates how we might recognise the chemical signatures of specific red pigments in extinct animals to determine how they evolved.

Professor Phil Manning, (University of Manchester), the lead palaeontologist involved in this study explained:

“The fossils we have studied have the vast potential to unlock many secrets of the original organism.  We can reconstruct key facets from life, death and the subsequent events impacting preservation before and after burial.  To unpick this complicated fossil chemical archive requires an interdisciplinary team to combine their efforts to crack this problem.  In doing this, we unlock much more than just palaeontological information.”

Co-author, Professor Roy Wogelius, from the University’s School of Earth and Environmental Sciences, added:

“This was a painstaking effort involving physics, palaeontology, organic chemistry, and geochemistry.  By working as a team, we were able, for the first time, to discover chemical traces of red pigment in fossil animal material.  We understand now what to look for in the future and our hope is that these results will mean that we can become more confident in reconstructing extinct animals and thereby add another dimension to the study of evolution.”

This exciting, collaborative effort from numerous scientific disciplines reveals that within fossils with exceptionally preserved soft tissues, evidence of black pigmentation can be identified, but furthermore, traces of the much more elusive red animal pigment may be found.  The chemical residue of black pigment, which colours such animals as crows, was first resolved by this team in a previous study nearly ten years ago.  However, the red pigment, characteristic of animals such as foxes and red pandas, is far less stable over geological time and proved much more difficult to detect.

Apodemus atavus Life Reconstruction

Apodemus atavus - mouse from the Pliocene helps reveal the evolution of pigmentation.

A life reconstruction of the mouse from the Pliocene – Apodemus atavus.

Picture Credit: The University of Manchester

Professor Wogelius went on to say:

“We had data which suggested red pigment residue was present in several fossils, but there was no useful data available to compare this to pigmentation in modern organisms.  So, we needed to devote several years to analysing modern tissue before we could go back and review our results from some amazing fossil specimens.  In the end, we were able to prove that detailed chemical analysis can resolve such pigment residue, but along the way we learned so much more about the chemistry of pigmentation throughout the animal kingdom.”

Shining a Light on Pigmentation Thanks to the Stanford Synchrotron Radiation Lightsource

To unlock the hidden data within the fossil material, the Manchester-based scientists collaborated with researchers at some of the brightest sources of light on the planet, using synchrotron radiation at the Stanford Synchrotron Radiation Lightsource (USA), and also at the Diamond Light Source (located in Oxfordshire), to bombard the fossils with intense X-rays.  It is the interaction of these X-rays with the chemistry of these fossils that enabled the team to be the first to recognise the chemistry of red pigmentation (pheomelanin), in fur from the exceptionally well-preserved remains of a mouse that scuttled about in the Pliocene Epoch (Apodemus atavus).

The key to the study was identifying trace metals incorporated by ancient organisms into their soft tissues and comparing these to the modes of incorporation into living species.  The chemistry shows that the trace metals in the mouse fur are bonded to organic chemicals in exactly the same way that these metals are bonded to organic pigments in animals with high concentrations of red pigment in their tissue.

In order to confirm the team’s findings, modern comparison standards were analysed by synchrotron radiation and by specialists in pigment chemistry based at the Fujita Health University in Japan.

A False Colour Image of the Fossilised Mouse

A false colour image of the fossil mouse.

A false colour image of the 3 million-year-old fossil mouse used in the red pigment study.

Picture Credit: The University of Manchester

Summarising the significance of this research Professor Manning stated:

“Palaeontology offers research that is more than relevant to our everyday life.  Information gleaned from the fossil record is influencing multiple fields, including; climate research, the burial of biowaste and radwaste, the measure of environmental impact of oil spills on living species with techniques developed on fossil organisms.  Whilst our research is firmly anchored in the past, we set our sights on its application to the future.”

The scientific paper: “Pheomelanin pigment remnants mapped in fossils of an extinct mammal” by Phillip L. Manning, Nicholas P. Edwards, Uwe Bergmann, Jennifer Anné, William I. Sellers, Arjen van Veelen, Dimosthenis Sokaras, Victoria M. Egerton, Roberto Alonso-Mori, Konstantin Ignatyev, Bart E. van Dongen, Kazumasa Wakamatsu, Shosuke Ito, Fabien Knoll & Roy A. Wogelius and published in Nature Communications

Everything Dinosaur acknowledges the assistance of a press release from Manchester University in the compilation of this article.

17 05, 2019

The Jurassic Angiosperm Gap

By | May 17th, 2019|Dinosaur and Prehistoric Animal News Stories, Main Page, Palaeontological articles|0 Comments

The Jurassic Angiosperm Gap

Today, the flora of the world is dominated by the angiosperms (flowering plants), they are the most diverse and widespread group of land plants comprising more than four hundred families, but their origin remains a mystery.  The fossil record for flowering plants is sparse, but there are numerous, unequivocal angiosperm fossils known from Cretaceous rocks.  Fossils of angiosperms from the Cretaceous appear abruptly and demonstrate a remarkable abundance of different forms.  The apparently rapid evolution of flowering plants in the Cretaceous was commented upon by Charles Darwin, the author of the ground-breaking “The Origin of Species”.  Darwin described the diverse Cretaceous-aged fossils of flowering plants when very few earlier flowering plant fossils were known as “a great abominable mystery.”

To read an earlier article (published in 2018), that looked at the puzzle of when angiosperms evolved: When Did Flowers First Evolve?

Fossils of Water Lilies (Nymphaeales) Are Known from the Cretaceous but when did the Flowering Plants Evolve?

A water lily in flower.

From the time of the Dinosaurs, but when did the angiosperms first appear?

Picture Credit: Everything Dinosaur

Molecular Clock Dating and Genome Analyses Indicate Origins Earlier in the Mesozoic

Molecular clock studies have frequently suggested an earlier origin for angiosperms in the Jurassic, or even potentially within the Triassic.  However, many studies have lacked extensive sampling, especially at the ordinal and familial levels.  Now, in a new scientific paper published in the journal “Nature Plants”, researchers from the Chinese Academy of Sciences have mapped and plotted a comprehensive angiosperm phylogeny, sampling nearly 3,000 chloroplast genomes from species representing all 64 known plant Orders and 85% of all the flowering plant families described to date.  This most intensive study of living flowering plants has been cross-referenced with the fossil record of angiosperms and indicates an origin of these types of plants in the Late Triassic (around 209 million years ago – Norian stage of the Late Triassic).

This earlier age for angiosperm evolution leaves a gap between the earliest fossils and the origins of flowering plants of almost 70 million years, roughly the length of the entire Jurassic period, the authors term this huge period of geological time as “the Jurassic Gap”.

Identifying “The Jurassic Gap” in the Angiosperm Lineage

The "Jurassic Gap" in the evolutionary history of flowering plants.

Identifying the angiosperm “Jurassic gap”.  If flowering plants originated around 209 million years ago, then there is a gap of some 70 million years in the fossil record which if filled in would plot the rise of this important group and their radiation.

Picture Credit: Nature Plants with additional annotation by Everything Dinosaur

Arising in the Late Triassic and Early Jurassic

The authors of the paper propose that the earliest lineages of flowering plants originated in the Late Triassic or Early Jurassic.  These early parts of the angiosperm family tree are represented (as expected), by a few species totalling no more than a couple of hundred taxa or so.  These early members of the angiosperm group include water lilies (Nymphaeales), the woody plant order Austrobaileyales, which contains star anise and the large shrub Amborella trichopodanative to the island of New Caledonia in the southwest Pacific Ocean, a plant which is regarded as the sister taxon to the remaining angiosperms.

The data generated by the scientists indicates that major diversifications subsequently occurred in the Late Jurassic and Early Cretaceous resulting in 99.95% of the extant diversity of flowering plants.  The relationships of the five major clades of this large diversification (core angiosperms) have long been difficult to determine and the researchers conclude that despite this extensive study, more work is required to resolve this aspect of flowering plant evolution.

Linked to the Rise of Insects – Symbiotic Relationships with Flowering Plants

If the first angiosperms arose in the Triassic, this corresponds with the timing of the evolution of several types of insects including katydids, crickets, alderflies and the common ancestor of the Lepidoptera (moths and butterflies).  However, the spectacular diversification of core angiosperms in the Jurassic and Early Cretaceous notably also coincides with the origin and evolution of the Phytophaga, arguably the most diverse radiation of plant-feeding beetles.  Their association with angiosperms has long been proposed to account for the apparent evolutionary success of the Phytophaga.  Furthermore, modern beetle diversity in general as well as other pollinators, including moths and butterflies, had their origins in the Cretaceous, which coincides with the rise of flowering plants to ecological dominance and the major diversifications of extant angiosperm diversity in the phylogeny as reported by the Chinese Academy of Sciences.

The Present-day Diversity of Beetles Could be Linked in Part to the Success of Flowering Plants

A beetle.

Soldier Beetle – the evolution and radiation of flowering plants is linked to the radiation of the Insecta – a result of the symbiotic relationship between many angiosperms and insects.

Picture Credit: English-Country-Garden.com

To read an article about ancient wing scales found in a drill core that suggests a Triassic origin for the Lepidoptera: Ancient Butterflies Flutter By

Why the Jurassic Gap?

One explanation put forward for the “Jurassic Gap” is that in the early days of flowering plant evolution, these plants were rare and thus the chances of any number becoming preserved as fossils were slim.  Another explanation proposed, is perhaps they occurred in habitats that were unsuitable for preservation such as forests.  Charles Darwin commented that it was “wretchedly poor conjecture” that angiosperms could have had a pre-Cretaceous history on a remote, but lost, island, meaning that all evidence of early flowering plants had been essentially wiped out.

A somewhat less exotic explanation is that the structures, flowers or fruits of early flowering plants were too small to now be confidently assigned to angiosperm lineages.  Perhaps, more fossils will be found to help plug the “Jurassic Gap”, but for the time being this period of seventy million years or so remains a mystery.

Everything Dinosaur acknowledges the assistance of a press release from the Chinese Academy of Sciences in the compilation of this article.

14 05, 2019

Archaeopteryx Gets Company

By | May 14th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Alcmonavis poeschli – Another Late Jurassic “Early Bird”

Scientists have identified a new species of “proto-bird” which was contemporaneous with Archaeopteryx (A. lithographica).  Known from a single, fragmentary fossil, excavated from the Lower Tithonian Mörnsheim Formation of the Solnhofen Archipelago, the species has been named Alcmonavis poeschli.  Its discovery supports the hypothesis that there were numerous bird-like dinosaurs in the Late Jurassic.

The Late Jurassic of Europe Could Have Been Home to Numerous “Proto-birds”

Archaeopteryx could have been one of numerous bird-like dinosaurs from the Solnhofen Archipelago.

Picture Credit: Carl Buell

A Right Wing from a Volant Animal

A. poeschli is represented by a right wing (specimen number: SNSB-BSPG 2017 I 133).  The bones are partially dislocated but lying in proximal association, the fossils consist of the humerus, radius, ulna, the hand and finger bones with claws.  Although there are only a handful of bones to study, they show a number of derived characters such as a pronounced attachment area for the pectoralis muscle and a robust second finger.  These traits indicate that Alcmonavis is a more derived avialan than Archaeopteryx.

A Photograph Showing the Holotype Fossil of Alcmonavis poeschli

Alcmonavis poeschli holotype fossil material.

Alcmonavis poeschli holotype.

Picture Credit: Bayerische Staatssammlung für Paläontologie und Geologie/AFP

The photograph (above), shows the wing of Alcmonavis poeschli as it was found in the limestone slab.  Alcmonavis poeschli is another example of a volant bird from the Jurassic period.  It may have been a more capable flyer than the urvogel (Archaeopteryx).  Scars on the wing bones suggest the placement of sizeable muscles, indicating that the raven-sized Alcmonavis was capable of flapping its wings with some force.

One of the authors of the scientific paper, published this week in the academic journal “eLife”, Oliver Rauhut of the Bayerische Staatssammlung für Paläontologie und Geologie (Bavarian State Collection of Palaeontology and Geology) stated:

“At first, we assumed that this was another specimen of Archaeopteryx.  There are similarities, but after detailed comparisons with Archaeopteryx and other, geologically younger birds, its fossil remains suggested that we were dealing with a somewhat more derived bird.  The wing muscles indicate a greater capacity for flying.”

This discovery indicates higher avialan diversity in the Late Jurassic than previously recognized.

Named after the Altmühl River

The genus name is derived from the old Celtic name for the Altmühl River which flows through the Solnhofen limestone region and from the Greek “avis” for bird.  The species name honours Roland Pöschl who leads fossil hunting expeditions to the Old Schöpfel Quarry, where the fossilised wing was discovered.

To read an article published in 2017 about another feathered dinosaur from Solnhofen: The Archaeopteryx That Wasn’t

To read an article from February 2019, that explains how the iconic Archaeopteryx feather fossil was reclassified: Iconic “Archaeopteryx” Feather Not From Archaeopteryx

13 05, 2019

“Oh We Do Like to be Beside the Seaside” – Triassic Marine Phytosaurs

By | May 13th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Austrian Phytosaur Fossils Point to Phytosaurs in Marine Environments

Look at most books that feature an illustration of the fauna of the Triassic and it is likely that squeezed into the colourful but so spurious illustration of early dinosaurs, beaked rhynchosaurs and cynodonts all going about their business but effectively ignoring each other, you will spot a phytosaur.  Phytosaurs, the long-snouted, semi-aquatic carnivores that resembled crocodiles but were certainly not crocodilian, were widely distributed during the Triassic.  However, very little evidence had emerged that linked these predators with marine ecosystems.  It had been thought phytosaurs were confirmed to freshwater or brackish environments.  The publication of a new scientific paper, reporting on the discovery of the remains of at least four individuals from an ancient lagoon, represents the best evidence yet that these formidable predators also inhabited the sea.

Phytosaurs in Marine Ecosystems

Mystriosuchus steinbergeri life reconstruction.

A newly described species of Austrian phytosaur provides evidence of a marine existence.  Mystriosuchus steinbergeri life reconstruction.

Picture Credit: Mark Witton (© 2019 The Linnean Society of London, Zoological Journal of the Linnean Society)

Mystriosuchus steinbergeri

Although the fossil remains were laid down in a coastal, lagoonal environment, these days, thanks to plate tectonics, the quarry site is two kilometres above sea level in a remote part of the Austrian Alps.  The fossils were found in 1980 by Sepp Steinberger, a member of a local caving club.  The species name (Mystriosuchus steinbergeri), was erected in his honour.  One of the reasons cited for the amount of time it has taken to fully study these fossils is that despite the relative abundance of phytosaur fossils compared to other Triassic vertebrates, there are not that many vertebrate palaeontologists that specialise in studying the Phytosauria.

Phylogenetic analysis positions this newly described species as the sister taxon to a clade comprising Mystriosuchus planirostris and Mystriosuchus westphali.  A study of the fossil bones indicates that the Austrian phytosaur specimens represent individuals that were at least eight years of age at the time of their death.  The palaeoenvironmental data recovered suggests that these archosaurian reptiles were living in a marine lagoon.  This provides strong evidence to support the idea that some phytosaurs may have adapted to living in saltwater as well as freshwater environments.

A Classic Triassic Diorama Depicting a Phytosaur

A phytosaur in a Triassic diorama.

A beautifully painted Triassic scene (Rudolph Zallinger).  A newly published scientific paper provides strong evidence for marine adaptations in the Phytosauria.

Picture Credit: Rudolph Zallinger

How Did They Die?

Everything Dinosaur contacted one of the authors of the scientific paper, Richard Butler (School of Geography, Earth and Environmental Sciences, University of Birmingham), enquiring about the discovery of four individuals, all roughly the same age and the same size (approximately 4 metres in length), being found together.

Professor Butler commented:

“As to how these animals died and were buried together, your guess is as good as mine!  It’s a puzzle, and I don’t have an answer.  However, I think it’s very unlikely that they died together on land and were somehow washed out tens of kilometres and buried together.  I think it’s more likely that they were living in the lagoon and died near to where they were buried.  Interestingly, the fact that there are multiple individuals all of a similar size might suggest some social/group behaviour, although again it’s quite speculative.”

When asked to put into context the significance of this evidence supporting the idea of some members of the Phytosauria adapting to marine environments, Professor Butler explained that there have been a handful of occurrences of the species Mystriosuchus planirostris recorded in marine sediments in northern Italy, and the basal phytosaur Diandongosuchus was also found in a marine deposit.  These fossil discoveries have led to speculation that both these species were possibly marine animals.  However, they’ve all been isolated specimens, and in the northern Italian sequences, for example, there is evidence to indicate that fully terrestrial animals had been washed into these marine deposits.  So, in the case of these fossils,  it is plausible that rather than being examples of marine phytosaurs, these are terrestrial phytosaurs that died on land and were washed out to sea.  The Austrian phytosaur material ascribed to Mystriosuchus steinbergeri might not be the first evidence found to support a marine environment hypothesis but it does probably represent the strongest evidence found to date.

The professor concluded that if he and his fellow authors are correct, then the phytosaurs represent yet another group of tetrapods that independently invaded marine environments.

The scientific paper: “Description and Phylogenetic Placement of a New Marine Species of Phytosaur (Archosauriformes: Phytosauria) from the Late Triassic of Austria” by Richard J Butler, Andrew S Jones, Eric Buffetaut, Gerhard W Mandl, Torsten M Scheyer and Ortwin Schultz published in the Zoological Journal of the Linnean Society.

8 05, 2019

A New Jurassic Scansoriopterygid Dinosaur – Ambopteryx

By | May 8th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Ambopteryx longibrachium – A New Bat-winged Dinosaur

Scientists from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), have identified a new species of flying dinosaur from Jurassic-aged strata in north-eastern China.  This dinosaur has been identified as a member of the Scansoriopterygidae dinosaur family and it had bat-like, membranous wings just like the related Yi qi, that was named and described back in 2015.  The little dinosaur, not much bigger than a starling, had a flap of skin from its arms to its torso, in essence a wing.  It has been named Ambopteryx longibrachium and this discovery supports the idea that within the forests of northern China during the Middle to the Late Jurassic, dinosaurs were experimenting with several different methods of gliding and powered flight.

A Life Reconstruction of the Newly Described Scansoriopterygid Dinosaur Ambopteryx longibrachium

Ambopteryx longibrachium life reconstruction.

A life illustration of Ambopteryx longibrachium.

Picture Credit: IVPP (Chinese Academy of Sciences)

Bizarre and Buck-toothed Little Flying Dinosaur

The fossil specimen was found by a local farmer who supplements his income like many folk in Liaoning Province by searching for fossils in the fine-grained sediments.  It is beautifully preserved and dates to around 163 million years ago, commenting on the discovery, one of the co-authors of the scientific paper, published this week in the journal “Nature”, Jingmai O’Connor of the IVPP stated:

“It would have been this tiny, bizarre-looking, buck-toothed thing like nothing alive today.”

The Beautifully Preserved Fossil Specimen (Ambopteryx longibrachium)

Ambopteryx fossil specimen.

Ambopteryx longibrachium fossil.

Picture Credit: Min Wang IVPP (Chinese Academy of Sciences)

A Secondary Form of Flight That Does Not Involve Feathers

Close to the origins of flight, dinosaurs closely related to birds were experimenting with a range of different wing structures.  One of the most bizarre of these is the scansoriopterygid named Yi qi, (pronounced: Ee-chee), which was described and named in 2015.  This little dinosaur had membranous wings, supported by a curved, rod-like bone (styliform), attached to the wrist.  Soft tissue proximal to the arm bones was interpreted as bat-like wings, although this interpretation was not widely accepted by the scientific community.  However, the discovery of another type of scansoriopterygid dinosaur with the same type of wings demonstrates that members of the Scansoriopterygidae were indeed taking to the air.

The new dinosaur, Ambopteryx longibrachium (meaning “both-wing” and “long arm,” a reference to this second method of dinosaur flight, one that does not involve feathered wings), provides confirmatory evidence of the evolution of dinosaurs with bat-like, membranous wings.

Palaeontologist Steve Brusatte, (University of Edinburgh), when asked to reflect on the significance of this newly published scientific paper commented:

“This fossil seals the deal, there really were bat-winged dinosaurs.”

Ambopteryx longibrachium – Takes to the Air

A gliding Ambopteryx longibrachium (dorsal view).

Ambopteryx longibrachium (dorsal view).  The speculated flying pose of this new Chinese dinosaur.

Picture Credit: Min Wang IVPP (Chinese Academy of Sciences)

An Evolutionary Dead End

The researchers conclude that marked changes in wing design evolved near the split between the Scansoriopterygidae and the avian lineage, the two clades took very different routes to becoming volant.  Furthermore, the scientists determine that the membranous wings supported by elongate forelimbs present in scansoriopterygids such as Yi and Ambopteryx was a short-lived evolutionary experiment and that the feathered, winged dinosaurs ultimately proved to be the more successful leading to the eventual evolution of the Aves.  The likes of Yi qi and Ambopteryx longibrachium were evolutionary dead ends.  Whether Ambopteryx was capable of sustained powered flight, or whether it moved from tree to tree entirely by passive gliding remains unknown.

Coming in to Land – Ambopteryx longibrachium

At home amongst the trees Ambopteryx longibrachium.

Coming into land, a gliding Ambopteryx moving effortlessly from tree to tree.

Video Image Credit: Min Wang IVPP (Chinese Academy of Sciences)

Stomach Contents Preserved

The stomach contents of the little dinosaur have been preserved.  The Chinese scientists recovered pieces of bone and small stones (gastroliths), which modern birds use to grind plant material, indicating Ambopteryx may have been omnivorous.  It may have lacked pinnate feathers, but the body was covered by a downy fuzz to help this small dinosaur keep warm.  Jingmai O’Connor speculates that male Ambopteryx may have sported long, ornamental tail feathers, as seen in other scansoriopterygids such as Epidexipteryx (E. hui).

The scientific paper examines the anatomical traits that enabled a mode of flight.  The wings of Ambopteryx were formed by elongated arm bones (humerus and ulna).  Aves (birds), have elongated finger bones (metacarpals), in effect, different solutions found in nature to achieve the same aim – volant activity.

Professor O’Connor added:

“The main lift-generating surface of bird’s wings is formed by the feathers.  In bats, pterosaurs and now scansoriopterygids, you have instead flaps of skin that are stretched out in between skeletal elements.”

Yi qi was Not Alone

It seems likely therefore, that with the discovery of a second bat-winged scansoriopterygid, there may be numerous other fossils of bizarre dinosaurs that were adapted to a life in the trees awaiting discovery in Liaoning Province.  It now seems that flight evolved more than once in the Dinosauria, Yi qi was not alone and the scientific community will provide further insight in the near future with regards to the remarkable and arguably the strangest of all the dinosaurs the Scansoriopterygidae.  Such research might be hindered by the small body-size of these creatures, the Ambopteryx specimen represents a sub-adult animal, it would have measured in life around 32 cm in length and weighed just a few hundred grammes.  Epidexipteryx and Yi qi were also small, E. hui has been estimated to have measured 30 cm long and weighed less than 200 grammes, whilst Yi qi is estimated to have had a wingspan of less than 60 cm and it would have been not much heavier.  The fact that any specimens of these tiny arboreal dinosaurs have survived at all is remarkable in itself.

A spokesperson from Everything Dinosaur commented:

“Much of our knowledge about these tree-dwelling dinosaurs has been derived from fossils discovered in the last twelve years or so.  Our blog was started back in 2007 and over the course of the life of our blog we have charted the rise in the knowledge and awareness surrounding the curious Scansoriopterygidae.  There has even been a model of scansoriopterygid produced by a mainstream manufacturer.  PNSO introduced a model of Yi qi this year.  Who knows what other remarkable dinosaurs are awaiting discovery?”

The PNSO Yi qi Dinosaur Model

Yi qi dinosaur model (PNSO).

PNSO Yi qi dinosaur model.

Picture Credit: Everything Dinosaur

To read about the discovery of Epidexipteryx: Is it a Bird? Is it a Plane? No, it’s Epidexipteryx!

To read about the discovery of Yi qiYi qi The Dinosaur that Thought it was a Bat

To view the Yi qi dinosaur model and the other figures in the PNSO model range: PNSO Age of Dinosaurs

6 05, 2019

Suskityrannus – Our Best Glimpse Yet of a Mid-Cretaceous Tyrannosauroid

By | May 6th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Suskityrannus hazelae – The Shape of Things To Come

The first of what will probably turn out to be numerous new Theropod dinosaurs from southern Laramidia has been announced today.  Writing in the academic journal “Nature: Ecology & Evolution”, a team of international scientists have described a new species of relatively small-bodied tyrannosauroid that helps to fill a gap in the evolution of the Tyrannosaur family.  Significantly, the new dinosaur, named Suskityrannus hazelae, has the same general body shape and feet adapted to running (arctometatarsalian feet), as the later, much larger Tyrannosaurs such as Albertosaurus, Gorgosaurus and T. rex.  This suggests that Tyrannosaurs evolved many of their characteristic features whilst they were relatively small, secondary predators.   When Suskityrannus roamed western North America some 92 million years ago (Middle Turonian faunal stage), this little Theropod was the shape of things to come.

A Life Reconstruction of Suskityrannus hazelae

Suskityrannus hazelae life reconstruction.

The newly described Suskityrannus walks past two unconcerned Zuniceratops.

Picture Credit: Andrey Atuchin

The Moreno Hill Dinosaur Assemblage

Suskityrannus heralds from the Zuni Basin of New Mexico, specifically the Moreno Hill Formation and it has been described based on two associated but fragmentary skeletons.  Even so, these fossils represent the most complete examples of early Late Cretaceous tryannosauroids described to date.  Dinosaur fossils from the Turonian faunal stage are exceptionally rare, the fossils from the Moreno Hill Formation have provided palaeontologists with an insight into the types of dinosaur that were the forerunners of the key groups of dinosaur that were to dominate the terrestrial ecosystems of North America towards the end of the Cretaceous.  For example, the beautiful life reconstruction of Suskityrannus by Andrey Atuchin (above),  shows a three-metre long Theropod about to feed on some garfish that have become stranded as a result of a flood.  The pair of Zuniceratops are unconcerned about the proximity of the meat-eater, they are many times heavier and have nothing to fear from the fleet-footed tyrannosauroid.  In the background, to the right of the image a large Ornithopod dinosaur can be seen, we think this is probably a life reconstruction of the basal hadrosauroid Jeyawati.

In essence, that is what makes the dinosaurs from the Moreno Hill Formation so significant.  These sediments were laid down before the diversification of the tyrannosaurids, hardrosaurids and ceratopsids, all key components in later Cretaceous dinosaur assemblages from North America.

A Powerful Bite

Named Suskityrannus hazelae, (pronounced Sus-key-tie-ran-us haze-ah-lie), analysis of the jaw bone indicates that this dinosaur had an elongated skull measuring between 25 and 32 cm in length.  Despite its small size, less than 3 metres long, with a hip height of around 1 metre, Suskityrannus had a powerful bite, foretelling the evolutionary direction of later Tyrannosaurs which were to evolve massive skulls with bone crushing bite forces.

The Fossil Skeleton of S. hazelae Compared to the Dentary (Lower Jaw) of Tyrannosaurus rex

Suskityrannus compared to the jaw bone of a T. rex.

The fossil remains of Suskityrannus compared to a lower jaw from a Tyrannosaurus rex.

Picture Credit: Virginia Tech

What’s in a Name?

The name Suskityrannus hazelae is derived from “Suski,” the Zuni Native American tribe word for “coyote,” reflecting this tyrannosauroid’s position in the ecosystem as a secondary predator.  The species name honours Hazel Wolfe whose support made possible many expeditions to the Zuni Basin of New Mexico.  The first evidence, including a partial skull was found in 1997 by co-author Robert Denton (GeoConcepts Engineering).  The second, more complete specimen was found in 1998 by Sterling Nesbitt, a high school student at the time, but now based at the Department of GeoSciences (Virginia Tech).  Dr Nesbitt is the corresponding author for the scientific paper.  The fossils were housed at the Arizona Museum of Natural History for many years before they were formally studied.

Co-author, Steve Brusatte (School of GeoSciences, University of Edinburgh) commented:

“Suskityrannus is a key link between the enormous bone-crunching dinosaurs like T. rex and the smaller species they evolved from.  The new species shows that Tyrannosaurs developed many of their signature features like a muscular skull, broad mouth, and a shock-absorbing foot when they were still small, maybe as adaptations for living in the shadows.”

Dr Sterling Nesbitt and Suskityrannus hazelae

Co-author Sterling Nesbitt and fossil remains of Suskityrannus.

Corresponding author Sterling Nesbitt, with the fossilised remains of Suskityrannus laid out in their anatomical position.

Picture Credit: Virginia Tech

The Moreno Hill and the Bissekty Formations

The Moreno Hill Formation is analogous to the Bissekty Formation of Uzbekistan.  Within the northern hemisphere, dinosaur fossils from the Turonian faunal stage are exceptionally rare, although thousands of miles apart, the strata are approximately the same age (around 90 million-years-old) and the dinosaur specimens found provide evidence of similar faunas.  The tyrannosauroid Timurlengia was named and described from fragmentary remains from the Bissekty Formation in 2016, the publication of a scientific paper on Suskityrannus will help palaeontologists to better understand how relatively small-bodied tyrannosauroids evolved into giant apex predators some twenty million years later.

To read about the discover of Timurlengia: Fossil Study Suggests How Tyrannosaurs Got Big

How Big Were the Arms of Suskityrannus?

As for that other famous Late Cretaceous Tyrannosaur body trait, the much reduced arms, scientists are very much in the dark about how big the forelimbs of Suskityrannus were.  Very little forelimb fossil material has been recovered.  Scientists can’t even say with any certainty whether Suskityrannus had two-fingered or three-fingered hands.  Cross-sectional analysis of slices of bone indicate that both known specimens were juveniles.  The fossils are providing further information on tyrannosauroid ontogeny.  Despite not being fully-grown, the authors are confident that Suskityrannus was not as big as its descendants, the famous apex predators of the Campanian and Maastrichtian faunal stages of the Cretaceous.

Commenting on the discovery a spokesperson from Everything Dinosaur stated:

“When we made our palaeontology predictions for 2019, the last prediction we made was that more tyrannosaurids would be named and described from fossil material associated with southern Laramidia.  We suggested that two new species would be named.   Suskityrannus hazelae has helped us to confirm our prediction made earlier this year, at least in part.  We are expecting more Theropod news to come out of the southern United States over the next few months.  These are exciting times for anyone studying the Tyrannosauroidea.”

To read about the discovery of a tyrannosauroid from central Utah that lived approximately four million years before Suskityrannus: Moros intrepidus Fleet Footed Tyrannosauroid Leaps 70 Million Year Gap

4 05, 2019

How Dinosaurs Ran Could Provide Key to Origins of Flight

By | May 4th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Caudipteryx Flapped its “Wings” as it Ran

Scientists from Tsinghua University (Beijing), in collaboration with colleagues from the Chinese Academy of Sciences have suggested that the way in which some Theropod dinosaurs ran caused their feathered arms to move up and down.  Involuntary wing flapping might have been the first stage in the evolution of powered, active flight.  This is the conclusion reached in a new scientific paper published in the academic journal “PLOS – Computational Biology”, after a series of highly innovative experiments that involved building a robotic dinosaur and strapping artificial wings to young ostriches.

Modelling the Running Action of Caudipteryx

Calculating the flapping of the wings (Caudipteryx).

Mechanically modelling the running action of the basal feathered dinosaur Caudipteryx.

Picture Credit: PLOS – Computational Biology

Ground Up or Tree Down

Most scientists now accept that the Dinosauria is divided into two divisions, the avian dinosaurs – the birds and the non-avian dinosaurs, essentially all the other dinosaurs.  In addition, it is also widely believed that a type of maniraptoran dinosaur (a clade that contains true birds and those dinosaurs closely related to birds), evolved into our feathered friends.  Trouble is, how did powered flight, a trait very closely associated with most birds alive today come about?  Were some dinosaurs arboreal, clambering amongst the branches of trees and they then evolved the ability to glide and finally powered flight came about in what is described as a “tree down” approach.  Or, were fast-running, cursorial dinosaurs learning to leap into the air and over many generations, feathered arms became longer and stronger and the lift generated led to the evolution of volant dinosaurs and subsequently the birds?  This theory is termed “ground up”.

The debate has persisted for more than a hundred years.

Proavis – A Hypothetical Attempt to Assess “Ground Up” – Fast Running Led to the Evolution of Powered Flight

A model of the hypothetical transitional animal Proavis.

A model of the hypothetical animal Proavis.  An early attempt to examine how fast-running bipedal animals might have evolved into birds.

Picture Credit: Grant Museum of Zoology

Taking a Mechanical Approach

The researchers adopted a mechanical approach to this evolutionary conundrum.  They looked at one of the most basal, non-flying feathered dinosaurs known – Caudipteryx and assessed whether if this dinosaur ran fast enough, its running gait might have caused its feathered arms to flap involuntarily.  In theory, if the arms were strong enough, the wings and their feathers large enough, flapping whilst running fast could generate lift and if the lift to body weight ratios were right, then the dinosaur could take to the air.  In essence, passive wing flapping may have been an evolutionary precursor to later active wing flapping and powered flight.

An Illustration of Caudipteryx

Cauditperyx.

A basal feathered dinosaur that could not fly, but could it flap?

Picture Credit: Everything Dinosaur

An assessment of the fossilised bones of the pheasant-sized Caudipteryx led the researchers to determine that Caudipteryx had a top speed of 8 metres per second (28.8 kmh or 18 mph).  However, simulations using mechanical and computer models suggested that at even lower speeds from 2.5 to 5.8 metres per second, the gait of Caudipteryx would have created strong enough vibrations through its body to cause the wings to flap.

Testing the Physical Movement of Artificial Wings on Young Ostriches

Young ostriches fitted with artificial wings.

Testing the movement of artificial wings in young ostrich locomotion study.

Picture Credit: PLOS – Computational Biology

A Life-size Robotic Caudipteryx

To test their calculations, the scientists built a life-size, robotic Caudipteryx and tested its running performance on a treadmill.  Several young ostriches were kitted out with artificial wings equipped with sensors that could detect lift and forward thrust, or any coefficient drag.  These birds were then put on the treadmill to see how they would perform.  In addition, five different sizes of feathers on the wings were tried, the larger feathers producing more results akin to the development of powered flight.

Five Different Wing Sizes and Feathers were Tested

Wing and feather variations used in the locomotion experiment.

Five different wing and feather combinations were tested.

Picture Credit: PLOS – Computational Biology

Professor John Hutchinson (Royal Veterinary College, London), an expert on animal locomotion, although not directly involved in the research, described this physical modelling approach as “ambitious and creative”, but questioned the paper’s main findings.  The study, for example, may have oversimplified the biology, reducing a living organism to a series of springs and constituent parts with individual mass, subsequently compiled to produce a single result.  Caudipteryx could have ran with its arms held very close to its body, helping it to reduce air resistance as it moved quickly, but also negating some of the lift and thrust that might have been generated by its feathered forelimbs.

Despite his reservations, Professor Hutchinson sees this study has helping to “lay groundwork that could be built upon and tested more rigorously.”

It seems that for the time being, the debate between “tree down” and “ground up” remains unresolved and it is not certain how much of a role passive arm flapping as a result of terrestrial locomotion influenced the evolution of active wing flapping, the precursor to a truly aerial existence.

1 05, 2019

Denisovans Lived on the “Roof of the World”

By | May 1st, 2019|Dinosaur and Prehistoric Animal News Stories, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Jaw Fossil Indicates Denisovans Occupied the Tibetan Plateau

Denisovans, occupied the Tibetan Plateau long before Homo sapiens arrived in the region.  Furthermore, the ability to cope with less oxygen at high altitudes may have been passed onto our species when ancient members of Homo sapiens, bred with Denisovans.  The analysis of a fragmentary lower jaw bone reveals the presence of Denisovans at least 160,000 years ago at the Baishiya Karst Cave complex in Xiahe, China.  The ability to survive in such extreme climates had been thought to be a unique trait of H. sapiens, that is now not the case and what is more, the enigmatic and poorly known Denisovans seem to have passed on a gene that helps modern people cope with living at high elevations.

A Digital Reconstruction of the Fossil Mandible

A digital reconstruction of the Xiahe mandible identified as Denisovan.

View of the virtual reconstruction of the Xiahe mandible after digital removal of the adhering carbonate crust.  The mandible is so well preserved that it allows for a virtual reconstruction of the two sides of the mandible.  Mirrored parts are in grey.

Picture Credit: Jean-Jacques Hublin (MPI-EVA)

The study, undertaken by a team of international researchers including Shara Bailey (New York University), as well as scientists from the Institute of Tibetan Plateau Research, the Chinese Academy of Sciences, Lanzhou University, and the Max Planck Institute for Evolutionary Anthropology, has been published in the journal “Nature”.

Using a technique known as ancient protein analysis, the researchers found that the mandible’s (lower jaw) owner belonged to a Denisovan population from Siberia.  This population occupied the Tibetan Plateau, regarded as the “Roof of the World” because it rises three miles (five kilometres), above sea level.  This suggests that the enigmatic Denisovans were adapted to a low oxygen environment.  In contrast, evidence of Neanderthals is rarely found above 2,000 metres and what evidence there is, probably indicates that Homo neanderthalensis populations only occasionally climbed to such heights, perhaps for the purpose of a special hunt or ceremony.  They do not seem to have persisted at high altitude.

The research team state that Denisovans had already adapted to living in this high-altitude setting significantly prior to the appearance of Homo sapiens.  Previous genetic studies found present-day Himalayan populations carry the EPAS1 allele in their genome, passed on to them by Denisovans, which helps with adaptation to their specific and demanding environment.

A Posterior View of the Fossil Mandible

Digital reconstruction of the Denisovan jaw bone from China.

Digital reconstruction of the Denisovan jaw bone.  Reconstructed area is shaded grey.

Picture Credit: Jean-Jacques Hublin (MPI-EVA)

Who were the Denisovans?

Denisovans are members of a hominin group currently only known directly from fragmentary fossils, the genomes of which have been studied from a single site, Denisova Cave in Siberia.  They are also known indirectly from their genetic legacy through gene flow into several low-altitude East Asian populations and high-altitude modern Tibetans.  The presence of a new species of ancient human was confirmed when a research team led by Svante Pääbo from the Max Planck Institute for Evolutionary Anthropology (MPI-EVA), conducted a genetic study on a single fossil finger bone from the Denisova Cave site.

To read an article from 2010 that summarises the Max Planck Institute for Evolutionary Anthropology research: Finger Bone Hints at New Species of Hominin.

Commenting on the significance of linking a fossil to the Tibetan Plateau, one of the paper’s co-authors Jean-Jacques Hublin (MPI-EVA), stated:

“Traces of Denisovan DNA are found in present-day Asian, Australian, and Melanesian populations, suggesting that these ancient hominins may have once been widespread.  Yet, so far, the only fossils representing this ancient hominin group were identified at the Denisova Cave.”

Indeed, Everything Dinosaur published a report back in 2016 that linked the Inuit people of the Arctic to a Denisovan ancestry: Extinct Human Cousin Helped the Inuit Survive.

A Photograph of the Actual Fossil Jaw Bone (Lateral View)

Denisovan fossil jaw bone ( Baishiya Karst Cave).

Xiahe Denisovan jaw bone from the Baishiya Karst Cave (Gansu Province, China).

Picture Credit: Dongju Zhang (Lanzhou University)

Discovered by a Monk

In this newly published paper, the researchers describe a hominin lower mandible that was found on the Tibetan Plateau in the Baishiya Karst Cave in Xiahe, Gansu Province, China.  The fossil was originally discovered in 1980 by a local monk who donated it to the 6th Gung-Thang Living Buddha who then passed it on to Lanzhou University.  Since 2010, researchers Fahu Chen and Dongju Zhang from Lanzhou University have been studying the cave site from where the mandible originated in a bid to find more human remains.  In 2016, a collaboration began with the Department of Human Evolution at the Max Planck Institute for Evolutionary Anthropology and although no DNA has been recovered, the team did manage to extract proteins from one of the large molars within the jaw.  These proteins were then categorised using a technique called ancient protein analysis.

The Reconstructed Denisovan Jaw Bone

Denisovan jaw bone identified on the Tibetan Plateau (digital reconstruction).

A view of the Denisovan jaw bone from China. The grey area represents reconstructed elements.

Picture Credit: Jean-Jacques Hublin (MPI-EVA)

Piecing Together the Face of a Denisovan

The fossil record of the Denisovans is particularly sparse, it is limited to just some teeth and part of a finger.  This is the first fossil of its kind to be found and perhaps, if more Denisovan fossils can be discovered, then it hints at the possibility that anthropologists might be able to reconstruct the skull.

Co-author Shara Bailey explained:

“Although we still do not know the shape and size of the Denisovan skull, now with a lower jaw we can start to piece together the puzzle of what they actually looked like”.

Everything Dinosaur acknowledges the assistance of a press release from New York University in the compilation of this article.

29 04, 2019

Cretaceous Crabs Ruffle Feathers

By | April 29th, 2019|Dinosaur and Prehistoric Animal News Stories, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Callichimaera perplexa et al Challenging the Definition of a Crab

An international team of scientists reported the discovery of a variety of Late Cretaceous marine crustacea that have challenged the current definitions of what makes a crab.  Writing in the academic journal “Science Advances”, the researchers from the University of Alberta, Kent State University, the University of Montreal, the Smithsonian Tropical Research Institute in Panama, the Canadian Parks and Wilderness Society, the National Autonomous University of Mexico, the University of Nevada, and the College of Communication and Design in Boca Raton, Florida, as well as Yale University , describe the discovery of hundreds of beautifully-preserved specimens from the USA and Colombia.

A Life Reconstruction of the Cretaceous Crab  Callichimaera perplexa

Callichimaera perplexa life reconstruction.

A life reconstruction of Callichimaera perplexa.

Picture Credit: Elissa Martin, (Yale Peabody Museum of Natural History)

The preserved remains include hundreds of tiny shrimp fossils and an entirely new branch of the evolutionary tree for crabs (Order Decapoda).

A Very “Goofy-looking” Crab – Callichimaera perplexa

According to lead researcher, Yale University palaeontologist Javier Luque, the most significant fossil discovery is Callichimaera perplexa, which at around 95-million-years-old, is the earliest example of a swimming arthropod with paddle-like legs since the eurypterids (sea scorpions), that are believed to have died out in the Permian.  The genus name derives from the mythical creature called a chimera, which was formed from the body parts of a variety of different animals.  In a press release from Yale University, it is stated that the binomial scientific name translates as “perplexing beautiful chimera.”

Examining a Fossil Specimen (Callichimaera perplexa)

Callichimaera perplexa fossil specimen.

Examining a Callichimaera perplexa fossil.

Picture Credit: Yale University

A Unique and Very Strange Cretaceous Nektonic Crab

Measuring around 2-3 centimetres in diameter, Callichimaera is described as looking very strange with large, unprotected compound eyes with no sockets, bent claws, leg-like mouth parts, a long body and an exposed tail.  It was nektonic (an active swimmer), as an adult it resembled typical crab larval stages.  This suggests that some ancient crabs may have retained a few of their larval traits into adulthood, amplified them, and developed a new body architecture.  This is an evolutionary process called “heterochrony” – a change to the timing or rate of development relative to the ancestor.

The Diverse Body Plans of Swimming Crabs and other Nektonic Arthropods

The huge variations in the Arthropoda body plan.

The diverse body plans of selected arthropods.

Picture Credit: Yale University

Luque commented:

“Callichimaera perplexa is so unique and strange that it can be considered the platypus of the crab world.  It hints at how novel forms evolve and become so disparate through time.  Usually we think of crabs as big animals with broad carapaces, strong claws, small eyes in long eyestalks, and a small tail tucked under the body.  Well, Callichimaera defies all of these ‘crabby’ features and forces a re-think of our definition of what makes a crab a crab.”

A Computer-generated Image Showing the Underside of Callichimaera perplexa

Digital reconstruction of Callichimaera (ventral view),

A view of the ventral side (underside of the body) of Callichimaera.

Picture Credit: Yale University

The scientific paper: “Exceptional Preservation of mid-Cretaceous Marine Arthropods and the Evolution of Novel Forms via Heterochrony” by J. Luque1, R. M. Feldmann, O. Vernygora, C. E. Schweitzer, C. B. Cameron, K. A. Kerr, F. J. Vega, A. Duque, M. Strange, A. R. Palmer and C. Jaramillo published in the journal Science Advances.

Everything acknowledges the assistance of a press release from Yale University in the compilation of this article.

28 04, 2019

A New Hadrosauroid Dinosaur from Mongolia

By | April 28th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Gobihadros mongoliensis – A Newly Described Hadrosauroid from Mongolia

Scientists have described a new species of basal hadrosauroid from the Baynshire Formation of the central and eastern Gobi Desert (Mongolia).  It has been named Gobihadros mongoliensis.  At approximately three metres long, this cow-sized, Ornithischian may not be the most impressive dinosaur to have been found, but its discovery is significant for vertebrate palaeontologists.  G. mongoliensis is the first non-hadrosaurid hadrosauroid from the Late Cretaceous of central Asia known from an almost complete, articulated skull and postcranial material.

A Skeletal Reconstruction of Gobihadros mongoliensis

Gobihadros mongoliensis skeletal reconstruction.

A skeletal reconstruction of the basal hadrosauroid Gobihadros mongoliensis.

Picture Credit: PLOS One

Writing in the on-line academic journal “PLOS One”, the researchers David Evans (Royal Ontario Museum, Ontario, Canada), Khishigjav Tsogtbaatar (Mongolian Academy of Sciences), David Weishampel (John Hopkins University, Maryland, USA) and Mahito Watabe (Osaka City University, Japan), have concluded that Gobihadros is similar to Bactrosaurus johnsoni from eastern China and Gilmoreosaurus mongoliensis from the Iren Nor region of Inner Mongolia.

Outside of the Hadrosauridae Family

A phylogenetic assessment places Gobihadros outside of the Hadrosauridae, the family of dinosaurs commonly referred to as the duck-billed dinosaurs.  Gobihadros most certainly had a broad beak, very typical of a duck-billed dinosaur, but it has been classified as a basal member of the Hadrosauroidea, essentially the next classification bracket up from the Hadrosauridae, encompassing all the duck-billed dinosaurs and all dinosaurs more closely related to them than to Iguanodon.

Views of the Skull and Jaw Bones of Gobihadros mongoliensis

Views of the skull and mandible of Gobihadros mongoliensis.

Skull and mandible (MPC-D100/763) of Gobihadros mongoliensis in left lateral (A), dorsal (B), ventral (C), and posterior (D) views.

Picture Credit: PLOS One

From the Baynshire Formation

The fossil material was collected over a period of several years from the sandstone and mudstone deposits from a number of sites associated with the Baynshire Formation.  The dinosaur was described from two superbly preserved specimens, a complete and uncrushed skull (MPC-D100/763) and the holotype, which consists of an almost complete skull and postcranial skeleton found largely in an articulated state.  Although, the exact date of the Baynshire Formation remains open to debate, recent studies place the sediments in the early Late Cretaceous (Cenomanian-Santonian faunal stages).

Line Drawings of the Skull and Jaws of G. mongoliensis

Line drawings of the skull of Gobihadros mongoliensis.

Skull (MPC-D100/763) of Gobihadros mongoliensis in left lateral (A), anterior (B), dorsal (C), and posterior (D) views.

Picture Credit: PLOS One

Helping Scientists to Understand an Evolutionary Transition

The exquisite nature of the fossil preservation and its completeness has provided palaeontologists with one of the most detailed anatomical records of a hadrosauroid.  New information has been compiled documenting the evolutionary transition of the Hadrosauroidea towards the Hadrosauridae.  In addition, comparison with the fossil remains of much younger hadrosaurids from the Late Cretaceous of Asia (Maastrichtian faunal stage), such as Saurolophus angustirostris, Kerberosaurus manakini, Wulagasaurus dongi and Kundurosaurus nagornyi suggests that later Asian hadrosaurids migrated into Asia from North America, rather than sharing a common Asian ancestor with Gobihadros mongoliensis.

The scientific paper: “A New Hadrosauroid (Dinosauria: Ornithopoda) from the Late Cretaceous Baynshire Formation of the Gobi Desert (Mongolia)” by Khishigjav Tsogtbaatar, David B. Weishampel, David C. Evans and Mahito Watabe published in PLOS One.

Load More Posts