A Saurophaganax for William

Favourite Dinosaur of Young Dinosaur Fan

Recently, team members at Everything Dinosaur met a young dinosaur fan called William.  William told us that his favourite dinosaur was Saurophaganax and that he loved watching the Saurophaganax clips on the BBC television programme “Planet Dinosaur”.

An Illustration of the Giant Theropod Dinosaur Saurophaganax

Fearsome predator of the Late Jurassic.

Fearsome predator of the Late Jurassic.

Picture Credit: Everything Dinosaur

Saurophaganax is the biggest carnivorous dinosaur described from the Morrison Formation of the United States.  It is a contender for one of the largest Theropod dinosaurs known from Upper Jurassic strata and the fossils, although fragmentary, indicate an animal in excess of twelve metres in length.  Originally described as Saurophagus, the site where the first fossils of this dinosaur were discovered also yielded Stegosaur and Camptosaurus fossil material.  It has been suggested that these two bird-hipped dinosaurs were prey for the lizard-hipped Saurophaganax, hence the part of the television documentary programme in which a Saurophaganax lays claim to a Camptosaurus.

Nice to have met you William.

Spiny Plants, Ungulates and the Savannah Habitat

The Evolution of Spiny Plants Holds Key to the Establishment of the Savannah

The continent of Africa contains a wide diversity of habitats, dominating the south, central part of Africa are the grasslands, the extensive savannahs that are home to a great diversity of iconic animals.  A team of international scientists writing in the academic journal “The Proceedings of the National Academy of Sciences United States”, have mapped the origins of the African savannah and concluded that the emergence of this ecosystem is, at least in part, down to the grazing habits of antelopes and their kin.

Ancient Bovids Influenced Habitat Formation in Africa

Rusingoryx illustrated

Honking to communicate in the hot savannah.

Picture Credit: Todd Marshall

The picture above shows an illustration of Rusingoryx atopocranion a wildebeest from the Pleistocene Epoch.  Grazing bovids and antelopes may have had a remarkable impact on the evolution of plant communities.

In a study that plotted flora/faunal relationships on a continental scale, the researchers identified which mammal browsers are most closely associated with spiny communities of trees.  The team were able to show that over the last sixteen million years or so, plants from unrelated taxa developed spiny defences against being eaten a total of fifty-five times.  This pattern of convergent evolution suggests that the arrival and diversification of bovids in Africa changed the rules for persisting in woody communities.  Contrary to current understanding, this new data indicates that browsers predate fire by millions of years as agents driving the origin of the African savannah.

The study was conducted in an unorthodox manner.  The researchers, which included biologists from McGill University (Montreal, Quebec, Canada), started by observing fauna and flora relationships in Africa today and then working backwards in time to the middle of the Miocene Epoch.

An Arms Race Between Plants and Animals

Many browsers like gazelles, delicately pick leaves off branches full of wicked-looking spines that are several centimetres long.  The scientists were able to uncover what happened in the past by mapping the distribution and evolution of the spiny plants on which gazelles and their relatives like to feed today.

A Gerenuk Antelope Browsing

A Gerenuk Antelope Browsing

A Gerenuk Browsing on Trees.

Picture Credit: Everything Dinosaur

Research team member, Jonathan Davies, (McGill University) commented:

“It’s been difficult to get a picture of how savannah ecosystems evolved because the conditions needed to preserve animal and plant fossils are very different from one another.  By working with the African Centre for DNA Bar-coding at the University of Johannesburg, we were able to sequence and compare DNA from nearly two thousand trees, and show that African plants only developed spines about fifteen million years ago. That was about the same time that a new type of mammal, antelope and their relatives, spread across the continent following the collision between the continental plates of Africa and Eurasia.”

Prior to this collision, the African continent had been dominated by the large, now extinct, ancestors of browsing elephants and hyrax.  These large herbivores would have bull-dozed trees and trampled vegetation, so spines were an ineffective defence against them according to the lead author of the study, Tristan Charles-Dominique (University of Cape Town).  However, antelopes and their relatives that arrived in Africa after the continental plate collision were highly efficient browsers, often using their delicate lips and prehensile tongue to remove leaves from branches.  It is likely that plants developed spines to defend themselves against these new plant “predators”.

Evolving a Spiny Defence Against Browsers

The study suggests a remarkable “arms race” between the trees and plant-eaters.  The arrival of new and efficient herbivores on the continent of Africa led to the evolution of more and more elaborate defences, including longer and longer spines.  One of the implications of this research is that the loss of large mammals like antelopes today, through human activities such as the bush meat trade, may have a substantial impact on the African landscape, with present day open savannahs being converted into thicket or brush.  Extensive forests may also make a comeback.

The Paper:  “Spiny Plants, Mammal Browsers and the Origin of the African Savannahs”.

Everything Dinosaur acknowledges the support of McGill University in the compilation of this article.

Remembering the Thylacine – Threatened Species Day

Remembering the Thylacine

On this day, eighty years ago, the last known Thylacine died at Beaumaris Zoo in Hobart.  It was on the 7th of September 1936, that staff at the Tasmanian zoo discovered “Benjamin”, as the animal was believed to have been named, dead.  Sadly, just two months earlier, the species Thylacinus cynocephalus had been granted protected status, after more than a hundred years of persecution.  Today, we live in what is regarded as more enlightened times, and September 7th in Australia is “National Threatened Species Day”, a day dedicated to honouring those people who work to protect Australia’s unique wildlife.  It is also a day for reflecting on how our own species has led to the demise of other species.  For example, the Thylacine was thought to attack and kill sheep and other domesticated animals and so it was hunted with bounties being paid for each “Tasmanian Tiger” killed.

The Last Known Thylacine circa 1935

A photograph of a Thylacine.

A picture of “Benjamin” the last known Thylacine to live in captivity.

Picture Credit: David Fleay

The Sad Tale of Benjamin – The Last Known Thylacine

Benjamin is believed to have been captured in the Florentine Valley area (south central Tasmania) in 1933 and brought to Beaumaris Zoo (Hobart).  Although once thought to be female, a more recent analysis confirmed that Benjamin was indeed, in all probability a male.  An inability to determine gender reflects the relative neglect the animal suffered in the zoo.  Indeed, the fact that the animal was even nick-named Benjamin has been challenged by a number of academics and authors.  The Tasmanian winter of 1936 was particularly severe and it seems that the last known Thylacine in captivity probably died of exposure after having been locked out of its sheltered sleeping quarters.  And so, the last Thylacine was dead.  Ironically, Beaumaris Zoo, for years dogged by financial difficulties, was to close shortly afterwards.  It was shut down by the Hobart City Council in the last week of November 1937.

In 1996, on the sixtieth anniversary of the death of the only Thylacine to have been given official protection, “National Threatened Species Day” was declared.  A time to reflect on the demise of the Thylacine and how similar fates await other species of flora and fauna unique to Australia unless action is taken to reverse their decline.

The CollectA Female Thylacine Model

Everything Dinosaur is proud to have added the beautiful CollectA female Thylacine model to its range of CollectA models.  The Thylacine, (Thylacinus cynocephalus), was the largest carnivorous marsupial to have lived in Australia in modern times and the last member of a once much more diverse group of marsupials.  The “Tasmanian Tiger” may be thought to be extinct, but is it?

The CollectA Thylacine Model

The CollectA Thylacine replica.

The CollectA Thylacine model.

Picture Credit: Everything Dinosaur

To purchase the CollectA “Tasmanian Tiger” model: The CollectA Thylacine Model

Is the Thylacine Extinct?

The main island that makes up the State of Tasmania is a fraction under 25,000 square miles in size, that’s around three times the size of Wales or about the size of the State of West Virginia in the USA.  There have been a number of reported sightings of “Tigers” both in Tasmania and on the Australian mainland.  Evidence for the existence of Thylacines is a little threadbare to say the least.  Blurred and very indistinct photographs, casts of footprints and some poor quality film footage, but nonetheless, there are a number of people, including academics who fervently believe that the Thylacine, although extremely endangered and very vulnerable, is still holding on.  Every now and then a new eyewitness account is published.

Let’s hope that the Thylacine still exists and that one day soon, September 7th will have even greater significance to the people of Australia.

Walking with Dinosaurs Down at the Beach

Surprise Discovery of Dinosaur Tracks At Tourist Hot Spot

Fossilised footprints of a large Theropod dinosaur have been discovered at one of Australia’s most popular tourist beaches.  Broome’s Cable Beach is a very popular tourist area and hundreds of people visit this beautiful part of the Western Australian coast every day.  However, the pristine white sands hide a secret, it overlies a series of Cretaceous rock exposures where plant fossils and occasionally dinosaur footprints can be found.

One of the Three-Toed Dinosaur Prints Found at Cable Beach

Dinosaur footprint at Cable Beach (Western Australia).

One of the three-toed dinosaur tracks at Cable Beach.

Picture Credit: ABC Kimberley, Sophia O’Rourke

Ms Bindi Lee Porth was collecting shells at the beach last Sunday evening, when she literally stumbled across an amazing fossil find.  She noticed a strange shape in the rock and as she puts it herself:

“I just sort of brushed all the sand away and it’s revealed this beautiful, like a bird, foot.”

The Broome Coastline and Dinosaur Tracks

This part of the coast of Western Australia is renowned for its dinosaur tracks, that date from the Early Cretaceous (130 million years ago), a time when Australia was part of a much larger land mass (Gondwana) and it was nearer the South Pole.  Despite the high latitude, the climate was temperate to sub-tropical and many different kinds of dinosaurs roamed the land.

A Close Up of One of the Dinosaur Footprints

Dinosaur tracks found on beach.

A close up of one of the exposed dinosaur footprints.

Picture Credit: ABC Kimberley

Last year, Everything Dinosaur reported on efforts by University of Queensland researchers to map the extensive trackways using drones.

To read an article about this: Mapping the Dinosaur Heritage of Western Australia

The three-toed prints were exposed by the shifting sands, to have a set of tracks found so close to such a popular tourist location is quite a surprise and Ms Porth initially doubted what she had found, after all, casts of dinosaur footprints set in concrete have been created elsewhere along the coast in a bid to inform visitors about the ancient heritage of this part of Western Australia.  However, after having the trace fossils examined by Queensland University palaeontologist, Steve Salisbury, it was confirmed that these prints were genuine.

Dr. Salisbury commented:

“There have been tracks spotted in the Cable Beach area over the years, most of those are Sauropod tracks, but this is the first time we’ve become aware of there being another type of dinosaur track in that area.”

Doctor Salisbury with a Latex Cast of a Three-Toed Dinosaur Footprint

Taking a latex cast of a dinosaur footprint.

Dr. Steve Salisbury with a latex cast of an Australian dinosaur footprint.

Picture Credit: ABC News/Erin Parke

More Than One Type of Three-Toed Dinosaur

Dr. Salisbury’s trained eyes spotted something else unusual about the tridactyl prints.  Claws marks at the end of the toes can be clearly made out so these tracks were probably made by a meat-eater, but some of the tracks are subtly different, this suggests that more than one type of Theropod dinosaur is represented.  The Queensland University based scientist hopes to study the casts and in situ prints in order to determine more information about the dinosaurs that created them.

Using a simple hip to stride length formula, Dr. Salisbury has calculated that some of the prints were made by a dinosaur that had a hip height of around two metres.  A spokesperson from Everything Dinosaur commented that although it was not possible to give an accurate size estimate for a dinosaur based on these preliminary findings and more measurements would need to be taken, but as a rough approximation, you could be looking at a dinosaur around six metres in length.  A dinosaur that size would be about as big as Australovenator, a fearsome meat-eating dinosaur that lived some thirty million years or so after these tracks were made.

It may not be the biggest meat-eating dinosaur tracks ever found, the prints don’t represent the biggest Theropod known from Australia, but they do indicate that even in the most unlikely places, amazing fossils can be found.

To read an article that calls for more research to be done on the Western Australia dinosaur tracks: More Research Urgently Needed to Help Preserve and Protect Western Australia’s Trace Fossil Heritage

What Other Tracks Might Lie Under the Sand at Cable Beach?

A three-toed dinosaur footprint.

One of the dinosaur footprints from Cable Beach (WA)

Picture Credit: ABC Kimberley

Update on “Sibirosaurus”

General Media Picks Up Story of Giant Siberian Dinosaur

A  number of media outlets recently carried the story of the discovery of giant dinosaur fossil bones in Siberia.  There were lurid headlines such as “terrifying newly discovered dinosaur was the size of eight elephants” and claims that the Siberian fossils represented one of the largest animals ever to have walked on Earth.  Readers of this blog will note that we at Everything Dinosaur tend to try and avoid hyperbole and the dinosaur in question, most likely a new species of long-necked dinosaur (likely to be a Titanosauriform), had already featured in the weblog back in March 2015.  The dinosaur has been given the nickname Sibirosaurus, but it has yet to be formally scientifically described.  The Titanosauriforms are the largest single group of dinosaurs within the Macronaria, a clade of Sauropods united by their very large naris  (nasal openings) in their skulls, which in a number of genera are actually much larger than the eye socket (orbit).

Media Outlets Getting Excited by “Sibirosaurus”

Macronarian Titanosauriform dinosaurs.

An artist’s impression of a typical Macronarian dinosaur.

Picture Credit: Damir G. Martin

The fossils of this dinosaur have been slowly but surely extracted from a layer of extremely hard sandstone, located halfway up a cliff.  To read Everything Dinosaur’s 2015 article on the excavation work and to see pictures of the fossil dig site: Sibirosaurus Strides In

Work is Continuing on the Fossil Bone Preparation

Fossil preparation work in the laboratory.

A member of the lab team works on the fossil bones of a Macronarian dinosaur.

Picture Credit: Tomsk State University

The picture above shows one of the lab team members carefully removing the rock-hard matrix from a large bone (looks like a vertebra).   Claims in a number of newspapers that the dinosaur is a heavy as eight elephants (estimated weight up to fifty tonnes) and that these fossils represent one of the largest land animals known are a little premature, although it probably does represent a new species.  Dinosaur fossils have been found before in the sandstone rocks of the Kemerovo region of southern Siberia, but the fossils, in all probability do represent a species new to science.

A Piece of Dinosaur Fossil Bone at the Dig Site

A piece of dinosaur fossil bone.

A photograph of the Siberian dinosaur fossil bone at the dig site.

Picture Credit: Tomsk State University

The research is being conducted by Tomsk State University, St Petersburg State University and the Zoological Institute of the Russian Academy of Sciences.  A spokesperson from Everything Dinosaur commented that a formal research paper on this new dinosaur taxon will, in all likelihood be published next year.

Work has already been completed on the sacrum and it is hoped that these fossils along with foot bones from a Titanosauriform found in 1995 and likely to belong to the same species, will go on public display.

Although Fragmentary it is Likely a New Species of Titanosauriform will be Erected

Fossils of a new Titanosaur from Siberia.

Fossils of “Sibirosaurus” ready for cataloguing.

Picture Credit: Tomsk State University

3.7 Billion Year Old Microbial Structures?

A Rapid Emergence of Life on Earth?

When did life on Earth begin?  That is a very difficult question to answer, however, a team of scientists have published in the journal “Nature” this week suggesting that stromatolites (microbial colonies) existed in shallow marine environments as early as 3.7 billion years ago.  It’s all to do with waves and squiggles preserved in sedimentary strata from south-western Greenland.

Do These Wavy Lines and Structures Preserved in Ancient Sedimentary Rocks Indicate the Presence of Colonial Bacteria?

Are these wavy lines stromatolite fossils?

Evidence for ancient stromatolites?

Picture Credit: University of Wollongong

In the picture above the white scale bar represents 4 centimetres.

Although the paper is not without its controversy, if these waves and squiggles do turn out to be the ancient signatures left by mats of bacteria, then they would predate the previously oldest known fossils (from Australia) by some 200 million years or more.  Such claims are hotly contested, about as hot as the young Earth when the researchers (from a number of Australian institutions as well as from the UK), claim these stromatolites first existed.

The Isua Supercrustal Belt

The bleak, desolate uplands of south-western Greenland hold a secret.  The rocks here are the oldest surviving piece of the Earth’s surface.  As our planet continues to warm, so ice sheets shrink and slowly and surely, like the advance of geological time itself, new parts of our planet’s ancient crust are exposed.  This geological feature is called the Isua Supercrustal Belt (ISB).  Professor Martin van Kranendonk (University of New South Wales), specialises in the study of ancient life forms, dedicating his career to examining rocks for traces of Archean and Proterozoic life.  He and his colleagues hypothesise that the waves and cones seen in the ancient Greenland rocks are the traces of stromatolite stacks.

Researchers Exploring the ISB of Greenland

The Isua Supracrustal Belt of Greenland

The bleak and deserted part of south-western Greenland – on the hunt for ancient fossils.

Picture Credit: Picasa

Professor Kranendonk commented:

“We see the original unaltered sedimentary layers, and we can see how the stromatolite structures grow up through the sedimentary layering.  And we can see the characteristic dome and cone-shaped forms of modern stromatolites.”

If this is evidence of microbial colonies preserved in rocks some 3,700 million years old, then they predate by some 220 million years the previous most convincing and generally accepted evidence for the oldest life on Earth, the stromatolite fossils from the 3,480 million year old Dresser Formation of the Pilbara Craton, Australia.  These ancient rocks located in Western Australia are mostly volcanic in origin but the strata also preserves evidence of hydrothermal locations (hot springs), indicated by the presence of large quantities of the mineral barite.  These areas are associated with wrinkled structures, columns and cone shaped rocks, interpreted as evidence of stromatolite structures having existed within the hot springs and surrounding areas.

The ISB fossil material indicates the establishment of shallow marine carbonate production with biotic CO2 sequestration by 3,700 million years ago, close to the start of our planet’s sedimentary record.  If this is the case, then genetic molecular clock studies would push back the origin of life to before the Archaen Eon and into the Hadean Eon.  The Hadean Eon is the very oldest part of the Earth’s geological record.  It covers the period from our planet’s formation some 4.57 billion years ago to around 4 billion years ago (the start of the Archean Eon).  This suggests that life began on our planet when it was still being bombarded by extraterrestrial bodies, remnants from the formation of our solar system (the “Great Cometary Bombardment”).

Shark Bay Western Australia

Stromatolites can still be found today in various parts of the world (freshwater and marine environments).  For example, they can still be seen around the coast of Western Australia in a very saline body of water called Shark Bay.  The mushroom shaped structures found on the floor of the bay are the work of cyanobacterial communities.  Layers of mineral grains are glued together by the sticky, colonial bacteria.

Living Stromatolites (Shark Bay Western Australia)

Stromatolites at Shark Bay (Western Australia)

Stromatolite structures exposed at low tide (Shark Bay)

Picture Credit: sharkbay.org

To read an article from Everything Dinosaur published in 2010 about fossil evidence for the earliest animals found: Sponge-like Fossils May Be Earliest Animals

The Importance of Allkaruen

The Significance of the Pterosaur Allkaruen

A few days ago, Everything Dinosaur featured an article on this blog about a newly described Early Jurassic Pterosaur named Allkaruen koi.  We were subsequently emailed by one young dinosaur fan asking us to explain the significance of this fossil discovery.

Time to Get Excited About Pterosaurs – Learning Lots about Flying Reptiles

Ikrandraco Pterosaur fossil

White bar shows scale.

Picture Credit: Scientific Reports/Xiaolin Wang et al

The photograph above shows the fossilised remains of Ikrandraco avatar, a new species of Pterosaur described in 2014.

To read our recent article on the discovery of a new Pterosaur (A. koi) from Patagonia (Argentina): New Long-Tailed Pterosaur from Patagonia

Pterosaur Fossils are Exceedingly Rare

Fossils of flying reptiles are exceedingly rare, of the 130 or so genera described to date, most are known from only a few fragmentary fossils, mere scraps of bone and teeth.  The light, delicate, pneumatic bones of Pterosaurs rarely survive the ravages of time and the fossilisation process.  Most corpses, don’t even get buried, the chances are the carcase would have been scavenged long before it settled on a lake bed or the bottom of a shallow sea.  Therefore, the naming of a new flying reptile species is, in itself, a significant event.  For Allkaruen koi, even more so, as the rocks in southern Argentina where the fossilised bones were found indicate that this flying reptile lived around 180 million years ago.

A Beautiful Braincase

The new Pterosaur genus has been erected after careful study of the skeletal elements including an almost perfect, three-dimensionally preserved braincase.  Most Pterosaur fossils are crushed, distorted or compacted but not in this case, one of just a handful of very well-preserved flying reptile braincases known in the fossil record.  The braincase of Allkaruen shows a unique combination of characteristics of both the Rhamphorhynchoids (non-monofenestratan breviquartossans) and the Pterodactyloidea – let’s explain what this means.

The Pterosauria – the Order of reptiles that includes all these flying reptiles can be split into to distinct and very different groups.

  1. Formerly referred to as the Rhamphorhynchoids (as the very well known Rhamphorhynchidae family is included in this group), but now known to include a number of other Pterosaur families that evolved in the Triassic and the Jurassic, characterised by long-tails and a lengthy fifth digit.
  2. The Pterodactyloidea essentially the vast majority of known Pterosaurs, a Jurassic/Cretaceous radiation of flying reptiles with thin bone walls, relatively long metacarpals and much shorter tails.

So, in short, the researchers have a braincase from an Early Jurassic Pterosaur that shows features of both groups, the basal group and the later, short-tailed, long toed, thin bone walled Pterodactyloidea.  By studying the braincase of Allkaruen the palaeontologists can learn more about how the Pterodactyloidea evolved.  They can see how the brains of flying reptiles changed over time.

A Phylogenetic Assessment of Allkaruen Compared to Rhamphorhynchus and the Later Pterosaur Anhanguera

The phylogenetic position of Allkaruen.

Where within the Pterosauria Order does Allkaruen fit in?

Picture Credit: PeerJ

The researchers compared the changing shape and structure of Pterosaur brains, comparing Allkaruen with the brain anatomy of Rhamphorhynchus (representing the basal group), with the brain anatomy of a later Cretaceous Pterosaur Anhanguera, a representative of the short-tailed Pterodactyloidea.  Allkaruen could be described as a sort of “halfway house” between these two groups, a snapshot in Pterosaur evolution permitting scientists to gain “insights into the origin of the Pterodactyloid neurocranium and improve our understanding of the tempo and mode of Pterosaur evolution.”

The scientists mapped the various elements of the brain by comparing the braincases of these three Pterosaurs, from this information they could plot the evolution of the inner ear, essentially the balance organ, vital if you are going to spend a long time in the air.  The brain volume of Allkaruen is much bigger than that of Rhamphorhynchus and from this it can be inferred that Allkaruen was a more advanced animal capable of better co-ordinated flight and faster reactions than the Rhamphorhynchidae.  The cerebellum (show in yellow in the three brain diagrams included in the picture above), is much larger in Allkaruen than it is in Rhamphorhynchus.  The cerebellum in vertebrates is found towards the back of the brain it coordinates and regulates muscular activity.  A bigger cerebellum is another indicator that Allkaruen was a better flyer than the more basal Pterosaurs.  This and other evidence is helping palaeontologists to understand more about how the Pterosaurs evolved.

That’s why this fossil discovery is so important.

Dinosaur Fossil Skulls as Teaching Aids

A Set of Eleven Dinosaur Skulls

At this time of year, more so than any other time of year, our offices are inundated with requests from teachers and teaching assistants regarding information on suitable dinosaur themed teaching resources for school.  With many of the Everything Dinosaur team members having a background in education, we do appreciate how busy educationalists are at the moment as they prepare for the start of the new academic year.

We have been helping a number of teaching teams as they prepare to introduce dinosaurs as a term topic theme.  Working under the “land before time” or the creative curriculum’s “footprints in the past”, Everything Dinosaur is able to advise and assist with the preparation of schemes of work.  Take for example, the Year 2 teacher who contacted our office this week, with a request to help provide suitable resources for her class of eager seven year-olds.

We recommended a set of model dinosaur skulls (Safari Ltd dinosaur skulls) and we helped the teacher further by providing additional information on each of the dinosaurs featured in this eleven piece model set.

A Set of Dinosaur Fossil Skulls Ideal for School

Dinosaur fossil skull models, ideal for school.

A set of eleven dinosaur fossil skulls.

Picture Credit: Everything Dinosaur

These well made and quite accurate plastic replicas represent herbivores, carnivores and even an omnivore.  Can the class work out what the dinosaurs ate by examining the skulls?  Can they identify a potential omnivore?  Naturally, this is a great way to help reinforce understanding regarding the terms herbivore, carnivore and omnivore.  Can the children identify living carnivores, omnivores and herbivores?  Where do human beings fit into this?

To view the dinosaur skulls and to see the range of other prehistoric animal models and replicas Everything Dinosaur offers: Safari Ltd Dinosaur and Prehistoric Animals

Identifying Dinosaurs by their Skull Shape

The dinosaur skull set provides lots of scope for independent research on dinosaurs and for sorting games.  For example, we recommend that the fossil skulls be buried in a small sand tray and then the children can have a go at excavating fossils using old art brushes and other digging tools.   What sort of tools would a palaeontologist use?  One teacher split his class into eleven groups and gave each group a different skull. Each group was then challenged to produce a science poster with lots of facts about their dinosaur.

Dinosaur Skull Models

Everything Dinosaur helping to identify dinosaur skulls.

Identifying dinosaur skulls.

Picture Credit: Everything Dinosaur

Commenting on the use of the skulls in education a spokesperson from Everything Dinosaur stated:

“These robust models are great for creative teaching projects.  Using inexpensive props such as these, teaching teams can conduct all sorts of lesson activities that appeal to all types of learners.  The fossil models are very kinaesthetic and children love to handle them and they are very well made and accurately represent real dinosaur fossil skulls.  These models not only help children learn about individual dinosaurs but they can gain an appreciation of the diversity of the Dinosauria and how different types of prehistoric animal adapted to particular ecological niches.”

New Long-tailed Pterosaur from Patagonia

Allkaruen koi – Braincase and All

A team of international scientists including Leicester University’s David Unwin and Oliver Rauhut (conservator at the Bavarian Collection for Palaeontology and Geology), have announced the discovery of a new species of long-tailed Pterosaur from Patagonia (Argentina).  Writing in the academic journal “PeerJ”, the researchers were able to infer new information about how Pterosaurs adapted to an aerial lifestyle thanks to the three-dimensional preservation of the cranial material.  From this skull material, the team were able to gain fresh insights into the braincase and the structure of the inner ear.  The new species of Pterosaur will help palaeontologists to better understand differences between the primitive, primarily long-tailed “rhamphorhynchoids”, also known as non-pterodactyloids and the more derived and later, short-tailed pterodactyloids.

An Illustration of the New Pterosaur (Allkaruen koi)

Allkaruen Pterosaru illustration.

An illustration of the newly described Jurassic Pterosaur from Argentina called Allkaruen.

Picture Credit: Gabriel Lio

The Evolution and Radiation of the Pterosauria

The fossilised remains of this new Pterosaur come from the Cañadón Asfalto Formation, exposed in the northern/central Chubut Province of southern Argentina.  The fossil material came from a single bedding plane formed from freshwater limestone deposits, indicating that there was a large, inland body of water present.  The fossils were scattered although elements such as the mandible preserved a degree of articulation.  The rocks of the Cañadón Asfalto Formation had been thought to be about 162 million  years of age (Callovian to Oxfordian faunal stages – latest Middle to earliest Late Jurassic), however recent radiometric and biostratigraphical analysis suggests that these rocks might be much older.  Research published in 2013 (Cúneo et al), indicates an age range for this formation of between 183 and 165 million years (Toarcian to Bathonian faunal stages).

The genus name comes from the local Tehuelche dialect word “all” for “brain” and “karuen” which means “ancient”, in recognition of the superb three-dimensional preservation state of the fossil  skull.  The species name means “lake” in the Tehuelche language, reflecting the fact that the fossils were found in lacustrine deposits,

Fossils and Line Drawings of the Allkaruen koi Material

Fossils of the Jurassic Pterosaur Allkaruen

Fossils of the braincase, line drawings of the braincase along with drawings of the mandible and vertebrae.

Picture Credit: PeerJ

Two Main Types of Pterosaur

Pterosaurs have remarkable skeletal adaptations for life in the air and they were the first vertebrates to achieve powered flight.  Two major body plans have traditionally been recognised, rhamphorhynchoids (non-pterodactyloids) and the pterodactyloids.  These two types of flying reptile differ considerably in their general anatomy and also they exhibit very different head postures and neuroanatomy (nervous systems and the study of the brain).  Computerised tomography was employed to scan the uncrushed braincase that enabled the scientists to infer more information regarding the shape of the brain and the inner ear.  This study has provided new information on the origins of the highly derived neuroanatomy of pterodactyloids, as, until this new fossil discovery, only a few three-dimensionally preserved braincases of flying reptiles were known and these demonstrated a large morphological gap between the specimens.  The braincase of Allkaruen has helped fill in a portion of that gap to give scientists a better understanding of how the flying abilities of these reptiles evolved.

Dr. Diego Pol (CONICET, Museo Paleontológico Egidio Feruglio, Trelew, Chubut, Argentina) and corresponding author for the published paper stated: 

“Allkaruen shows an intermediate state in the brain evolution of pterosaurs and their adaptations to the aerial environment.  As a result, this research makes an important
contribution to the understanding of the evolution of all of Pterosaurs.”

A phylogenetic analysis was undertaken and Allkaruen is nested between monofenestratan breviquartossans (Rhamphorhynchidae) and derived pterodactyloids.  Given the age of the fossil and its phylogenetic affinities to Rhamphorhynchus and the Pterosaur known as Darwinopterus it has been suggested that this flying reptile had a long tail with a diamond shape rudder on the end of it.  Analysis of the cranium indicates that Allkaruen had two parallel crests on the top of its skull and it appeared to have teeth restricted to the middle and anterior (front) part of its jaws.  Although the exact diet of this Pterosaur is not known, given the context of the fossil material and the shape of the teeth, Allkaruen most likely fed on fish.

To read an article on the transitional fossil Darwinopterus: Darwinopterus – A Transitional Pterosaur

Dr. Oliver Rauhut has had a busy couple of weeks, he was also one of the principal authors of the scientific paper on the Early Jurassic meglosaurid Wiehenvenator.  To read about the “Monster of Minden”:Wiehenvenator albati – The Monster of Minden

Wiehenvenator albati – “The Monster of Minden”

The “Monster of Minden” – Wiehenvenator albati

A new species of large, Middle Jurassic carnivorous dinosaur has been described.  Writing in the academic journal “Palaeontologica Electronica” the researchers, which include Dr. Oliver Rauhut, (conservator at the Bavarian Collection for Palaeontology and Geology), identify this new Theropod as a member of the Megalosauroidea.  Named Wiehenvenator albati, it could be a potential sister taxon to Torvosaurus and a dinosaur that might have been about the same size as Torvosaurus gurneyi, reaching an estimated length of around ten metres.

An Illustration of the Newly Described Middle Jurassic Theropod from Germany

New dinosaur from Germany (Wiehenvenator)

Scale bar = 1 m (an illustration of Wiehenvenator)

Picture Credit: Palaeontologica Electronica (based on an illustration of Torvosaurus by Scott Hartman

The picture above shows the known fossil bones of Wiehenvenator.

A German Dinosaur

Fragmentary fossils including elements from the skull and jaws, caudal vertebrae, ribs and bones from the lower legs and ankle were excavated from a disused quarry located in Northrhine-Westphalia (Germany) back in 1999.  The fossils were found by chance, it was a routine inspection, however, once the first bones had been discovered a field team was brought in to ensure all the fossil material present could be collected.  The strata in which the fossil material was found are Middle Callovian in age (around 163 to 165 million years old) and they represent marine sediments.  During this time, much of the land that was to form western Europe lay under a warm, shallow tropical sea.  A number of small islands existed and it seems that this archipelago was home to this hunter, a dinosaur that is estimated to have weighed more than two tonnes.

Skull and Elements of the Jaws in their Anatomical Position

The skull and jaws of Wiehenvenator.

The skull and jaw fossils located in their anatomical position (Wiehenvenator).

Picture Credit: Palaeontologica Electronica

“The Monster of Minden”

Nicknamed “The Monster of Minden”, due to the town’s close proximity to the fossil dig site, Wiehenvenator was probably the apex predator on the island archipelago.  The teeth associated with this dinosaur are strongly recurved with the root making up more than two thirds of the tooth length.  The largest teeth identified so far (from the maxilla), measure in excess of 13 centimetres long.

The Teeth of Wiehenvenator albati (Various Views)

The teeth of the "Monster of Minden"

The strongly recurved teeth of Wiehenvenator.

Picture Credit: Palaeontologica Electronica

The picture above shows various views of the fossil teeth associated with the jawbones or found as loose items at the dig site.  The scale bar for 1 and 2 is 1 centimetre, the scale bar in the other images represents 5 centimetres (except picture 9).  The dinosaur was named Wiehenvenator for the Wiehengebirge, a chain of hills south of the town of Minden, where the holotype specimen was found and venator, Latin for hunter.  The trivial name honours Friedrich Albat, who found the holotype specimen.

Commenting on the significance of the discovery, Dr. Rauhut stated:

“Apparently there was in these islands a wide range of sometimes very large predators mainly from the group of Megalosauroidea as finds from France and England, as well as the new predators from Germany show.  The Megalosauroidea were the first giant predatory dinosaurs of Earth’s history.”

Differences in the Middle and Late Jurassic Theropod Fossil Records

The discovery of Wiehenvenator adds to the number of large Theropods known from the Callovian faunal stage of the Jurassic.  The research team comments on the number of large Theropods from the Middle Jurassic that are classified as Megalosauroids and they suggest that a rapid radiation of Megalosaurs is suggested between the Toarcian and the Bathonian faunal stage of the Jurassic (approximately 183 to 166 million years ago).  The scientists postulate that this radiation and increase in the number of Megalosaurs was probably triggered by the Pliensbachian-Toarcian extinction event that took place around 183 million years ago.  They comment that this extinction event may have been more significant for Theropod evolution than the larger end Triassic mass extinction.  The team then go on to review the changes in Theropod genera that took place from the Middle Jurassic onwards.

Two Views of the Right Maxilla (Upper Jaw Bone) of Wiehenvenator

The right maxilla of Wiehenvenator.

Right maxilla of Wiehenvenator albati in lateral (1) and medial (2) views

Picture Credit: Palaeontologica Electronica

The picture above shows two views of the right maxilla of Wiehenvenator albati, top (1) lateral view and bottom (2) medial view.

Less Megalosaurs More Allosaurs

The fossil record indicates a faunal turnover from Megalosauroidea dominated Middle Jurassic to Allosauroid/Coelurosaur dominated Late Jurassic Theropod faunas. The researchers plotted the number of different Theropod fossils found globally between the Middle Jurassic to the Late Jurassic.  Although the paucity of the fossil record makes a complete analysis impossible, the team did infer that there was a change in the proportion of different types of Theropod dinosaur represented as the Jurassic progressed.  The once dominant Megalosaurs were replaced by Coelurosaurs and Allosaurs.

Middle Jurassic Theropods Compared to Late Jurassic Theropods (Assessed by Clade)

Changing Theropod genera during the Jurassic.

A fossil record comparison of Theropods (Middle Jurassic compared to Late Jurassic).

Picture Credit: Palaeontologica Electronica

The Impact on Large Taxa (Apex Predators)

Theropod faunal turnover in the Jurassic.

Theropod faunal turnover (taxa estimated to be >250 kgs in size).

Picture Credit: Palaeontologica Electronica

When body mass is considered and Theropod dinosaurs estimated to be less than 250 kilogrammes in weight are removed, the impact of the rise in the number of Coelurosaurs is lost, suggesting that these dinosaurs did not rise to the apex predator niche during this period.  Large megalosaurids which dominated the apex predator niche globally during the Middle Jurassic had been substantially replaced by allosaurids by the end of the Jurassic.  The scientists are quick to point out that these figures are not conclusive, bias because of the large number of Theropods from the Upper Jurassic Morrison Formation is discussed along with the difficulties of undertaking analysis of this sort due to the relatively poor fossil record of large meat-eating dinosaurs over the time period studied.

However, an analysis of environmental preferences of Allosauroids and Megalosauroids indicates that the former preferred inland environments, whereas the latter are more common in nearshore environments.  From this it could be inferred that megalosaurids preferred to “be beside the seaside”.

The publication: “A new Theropod dinosaur megalosaurid from the late Middle Jurassic (Callovian) of north-western Germany: Implications for Theropod evolution and faunal turnover in the Jurassic.  By: Oliver WM Rauhut, Tom Huebner, and Klaus-Peter Lanser. In: Palaeontologia Electronica 2016.

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