Dinosaur Tracks Getting Mapped in Western Australia

The extensive dinosaur tracks that can be found along the coast of western Australia are getting plenty of tender loving care as a team of scientists led by researchers from the University of Queensland attempt to map and produce three-dimensional images of all these ancient trace fossils.  Researchers are setting out to map the dinosaur heritage of western Australia.

The fossilised footprints, permitting palaeontologists to go “walking with dinosaurs” are found near to the town of Broome (Western Australia) and north along the coast of the Dampier Peninsula, a relatively remote area, some nine hundred kilometres south-west of the city of Darwin.  The dinosaur trackways were granted National Heritage status, after a successful lobbying campaign, back in 2011, yet scientists have not been able to map all the tracks and prints preserved in this area, famous for its high tides.

Australia’s Dinosaur Heritage

The tides are part of the problem, this is a macro-tidal environment with tidal surges in excess of ten metres frequently occurring.  A number of prints are only exposed for a few hours a day whilst other tracks are only exposed on extremely low tides that occur just a couple of times per year.

A Jumble of Sauropod Prints Exposed on the Shoreline

These tracks could have been made by a herd of sauropods.

Picture credit: Dr Steve Salisbury

The Dinosaurs of Western Australia

Back in the spring of 2014, Everything Dinosaur reported in this blog on the calls for more research to be done on this unique fossil assemblage.   The hundreds of tracks represent many kinds of Early Cretaceous dinosaurs – theropods, stegosaurs, ornithopods and sauropods.  Some of the footprints believed to have been made by sauropods (long-necked, large-bodied, long-tailed giants) measure over 1.5 metres in diameter, making them some of the largest dinosaur trace fossils known to science.

To read this earlier article: Call for More Work to be Done on Western Australia’s Dinosaur Tracks.

Although, some of the tracks, especially the three-toed (tridactyl) prints are very obvious, the only way the extent of the tracks can be fully appreciated is by viewing them from the air.  Drones and light aircraft have been employed by the researchers to photograph and plot the dinosaur footprints.  In addition, some of the drones and aircraft have been kitted out with LiDAR equipment, which is helping to create a three-dimensional map of the terrain.  LiDAR (light detection and ranging), uses pulsating laser lights to plot features in the landscape in combination with satellite positioning technology to make highly accurate maps of the tracks.

A Variety of Research Methods Employed

More mundane research methods are also being employed such as photographing individual prints and making silicon rubber moulds.  All this research is very worthwhile as some of the prints are being rapidly eroded away by the action of the sea and tides.

Drones are Used to Plot the Dinosaur’s Movements

Dr Salisbury and colleagues are using drones to plot the trackways.

Picture credit: Damian Kelly

Early Cretaceous Dinosaur Tracks

It is believed that these tracks were made in the Early Cretaceous, around 130 million years ago (Barremian faunal stage of the Cretaceous), these fossils are something like twenty million years older than the dinosaur fossils associated with Queensland such as the titanosaurs Diamantinasaurus and Wintonotitan.

Commenting on the mapping project, Dr Steve Salisbury (University of Queensland) stated:

“These tracks are at least 15 to 20 million years older than the majority of dinosaur fossils that have been found at sites in eastern Australia.  We can, to a degree, accurately reconstruct scenes that happened 130 million years ago.  That’s not imagination, that’s piecing it together from the evidence found in the rocks.  It’s a powerful way of bringing these ancient worlds back to life.”

We at Everything Dinosaur wish the research team every success with their colossal mapping effort.  They are helping to preserve and to secure data from a very important Early Cretaceous fossil site.

CollectA have produced a number of models of dinosaurs that once roamed Gondwana, including titanosaurs, stegosaurs and theropods: CollectA Deluxe Prehistoric World Figures.

Fragmentary Fossils from Australia Provide Clues to the Origins of the Megaraptorids

Meet Australia’s largest known theropod, a predator that would have exceeded seven metres in length and a dinosaur armed with dreadfully sharp and powerful claws.  Claws, that unlike the dromaeosaurids the famous “raptors”, with their sickle-toe killing claws, were found on the hands.  Say hello to the newest member of a bizarre group of theropods the megaraptorids, although you can’t be formally introduced yet, as this meat-eater does not have a scientific name.

Australia’s Largest Meat-Eating Dinosaur Known to Date

An Early Cretaceous predator.

Picture credit: Julius T. Csotonyi

The Megaraptorid Phylogeny

The megaraptorids are represented by a number of genera, most of which are known from very few, fragmentary fossils.  Their phylogenetic relationship with other theropods remains in doubt, some palaeontologists have suggested that this group of meat-eating dinosaurs from the Southern Hemisphere may be related to the Coelurosauria clade, whilst other scientists have proposed that this group should be nested within the allosaurids.

Whatever the exact taxonomic relationship, these dinosaurs are characterised by having large hand claws, specifically an oversized first digit (thumb claw).  This new Australian dinosaur, whose fossils were found in an opal mine back in 2005, is no exception, based on a partial manual ungual (claw bone), it has been estimated that this carnivore had a twenty-five centimetre long thumb claw.

Megaraptorid

This newest member of the theropod family of Australia, is just one of two meat-eating dinosaurs to be known from more than a single bone* from “Down Under”.  It has been nicknamed “Lightning Claw”, this has nothing to do with this dinosaur’s imagined reactions, but a reference to the outback town of Lightning Ridge in New South Wales, where the fossils were found by opal miners Rob and Debbie Brogan.

The fossils are natural casts of opal and consist of a metatarsal, parts of the forearm, pieces of rib, fragments of the pelvis and a partial giant claw from the right hand.

Views of the Natural Cast of the Proximal End of the Claw

The strong hands with their highly recurved claws could have been used to dismember prey.

Picture credit: Bell et al 2015

Australovenator wintonensis

* The other Australian theropod dinosaur known from more than one bone is Australovenator (Australovenator wintonensis) the fossils of which come from Queensland but were found in strata at least 10 million years younger than the New South Wales fossil find.

Since Australovenator also possessed over-sized hand claws, it is likely that these two dinosaurs were related, the interpretation of “Lightning Claw” created by the very talented Julius Csotonyi, is based on more substantial dinosaur remains including those of Australovenator.

A Model of the Dinosaur Called Australovenator

The CollectA Australovenator replica.

Picture credit: Everything Dinosaur

Dinosaur Models

The dinosaur model pictured above is the CollectA Prehistoric World Australovenator replica, to view this large model range: CollectA Prehistoric World Dinosaur Models.

Lead author of the scientific paper, just published in the journal “Gondwana Research”, Dr Phil Bell (University of New England), explained the significance of these opalised fossils:

“I immediately recognised this fossil was something new.  When I compared it to other Australian and South American dinosaurs, it was clear it was a megaraptorid which is a relatively rare group of dinosaurs, mostly known from Argentina.”

Grappling Hooks for Hands

Dr Bell along with co-authors from the University of Bologna (Italy) and Elizabeth Smith of the Australian Open Centre, which received the fossils as a donation from Rob and Debbie Brogan, have stated that the nasty predator with grappling hooks for hands, a sort of Freddy Krueger of the Dinosauria, roamed the flood plains of New South Wales around 110 million years ago (Albian faunal stage).  The age of the strata is significant as this makes “Lightning Claw” the earliest representative of the megaraptorids known.

Australia’s Cretaceous dinosaur fauna is largely made up of dinosaurs that are known from elsewhere on the landmasses that once made up the super-continent of Gondwana.  It had been thought that the majority of the Australian dinosaurs were immigrant taxa.  This may be a too simple explanation and a more complex two-way faunal interchange between Australia, Antarctica and South America may have taken place.

Commenting on this Dr Bell stated:

“What is fascinating about this discovery is it changes the popular notion that Australian dinosaurs came from ancestors derived from Africa and South America – instead the “Lightning Claw” appears to be the ancestor of all megaraptorids, meaning this group appeared first in Australia.”

Tyrannosaur Footprint Found in British Columbia

Palaeontologists and ichnologists (scientists who study trace fossils including footprints), are examining the preserved impression of a three-toed footprint made by a large dinosaur during the Late Cretaceous.  The single print measures fifty-nine centimetres long and it may have been made by a substantial tyrannosaurid.

Dinosaur Footprint

The footprint was found approximately ten kilometres from the small settlement of Tumbler Ridge.  Something like fifteen tyrannosaur footprints have been discovered to date, from locations as far apart as New Mexico, Alberta and Mongolia, but this is the ninth print to have been reported from British Columbia.  The print was found by Carina Helm, a geography student at the University of British Columbia who was out working in the area with her father.  The track was found on August 20th.

Explaining the circumstances behind the discovery, Carina explained:

“My dad and I were returning in the evening from repairing boardwalks on one of the hiking trails, when I told him I knew of some big exposed rock slabs.  We worked out that these were maybe from an age that could feature dinosaur tracks, so we decided to make a detour to have a look.”

The father and daughter team did not have to search for long to find the fossil.

The Three-Toed Dinosaur Footprint

The white line helps to show the outline of the track.

Picture credit: The Helm Family

Commenting on the Dinosaur Footprint Discovery

Looks like mobile phones have lots of uses, for example, the phone in the picture helps to show scale.

Carina added:

“The very first rock I went to, right beside the road, had this huge track-shape on it with three toes.  I thought, surely, that is too big to be a footprint?  I showed it to my dad and next thing he was on his cell-phone to Rich McCrea telling him about the find.”

The Peace Region Palaeontology Research Centre

Rich McCrea, is one of the palaeontologists at the The Peace Region Palaeontology Research Centre (P.R.P.R.C.), based in Tumbler Ridge.  This institute was founded in 2003 to help excavate, preserve and showcase the vertebrate body and trace fossils associated with this part of the Canadian Province.  Most of the footprints alleged to have come from large theropods that have been found in this region have come from remote, difficult to access locations.  In contrast, this new find was close to a road and is much more accessible.

A Likely Tyrannosaurid Track

Rich and colleague Lisa Buckley were able to confirm that this track was most likely made by a tyrannosaurid.  Although the print measures fifty-nine centimetres long, the foot that made it would actually have been bigger, the tip of the longest toe and its claw impression have been eroded away.  When asked to speculate the type of tyrannosaur that might have made this track, the P.R.P.R.C. palaeontologists have suggested that this track could  have been made by an Albertosaurus.

A Model of an Albertosaurus (Large, Late Cretaceous Tyrannosaur)

Albertosaurus (Carnegie Collectibles – Safari Ltd).

Picture credit: Everything Dinosaur

To view the range of prehistoric animals made by Safari Ltd: Safari Ltd Dinosaur Models.

Outlining how the scientists concluded that this was indeed the footprint of a tyrannosaur, Rich McCrea stated:

“It can sometimes be a challenge to identify the maker of a single print, especially one that has been weathered by the elements.  Even with the tips of the digits (the claw impressions), eroded away, the footprint found by Carina Helm still possesses characteristics that make it identifiable as the product of a meat-eating (theropod) dinosaur.  In addition to the morphological features of the footprint, which bears great similarity to the ones discovered in the Autumn of 2011 and subsequently ascribed to the ichnospecies Bellatoripes fredlundi, the size of the print and the age of the rocks it was found in provide further evidence that the track-maker was a tyrannosauroid.”

A Problem Fossil

This fossil is posing a bit of a problem for the Tumbler Ridge Museum Foundation, the organisation that established the P.R.P.R.C., the fossil is close to a road and therefore it could be vandalised or stolen.  Attempts could be made to remove the specimen, but this too, presents problems.  The slab of rock containing the print is large and transporting the fossil to Tumbler Ridge would present quite a logistical challenge.

Young Carina is proving to have quite a knack for finding trace fossils, earlier in the Summer, she was part of a team that found two other trackways preserved in much older rocks in the Tumbler Ridge area.

How Did the Ankylosaur Get Its Club Tail?

Dinosaurs as “Living Tanks”

Ankylosaurs are often described as “living tanks” these quadrupeds seemed to have taken body armour to the extremes with some specimens such as Saichania from Asia and the Late Cretaceous North American ankylosaurids Euoplocephalus and Ankylosaurus even having armoured eyelids.  They were a very diverse and widespread group of ornithischian dinosaurs, in every sense of the world.  True, ankylosaur fossils have been recorded from China, Mongolia, Canada, the United States, Australia and there have even been fragmentary bones attributed to an ankylosaur found near Folkestone (Kent, England).

In addition, these animals have very wide pelvic regions in proportion to the rest of their robust bodies.  The wide pelvis is an adaptation to accommodate a large gut.

Heavily Armoured Dinosaurs with a Long Evolutionary History

Armoured dinosaur models.

Picture credit: Everything Dinosaur

Most children can describe these herbivores, they may be very well known members of the Dinosauria, with an albeit brief appearance in the film “Jurassic World” adding to their popularity, however, a mystery surrounding the Ankylosauridae may finally have been solved.

How Did the Ankylosaur Tail Club Evolve?

By mapping the evolutionary history of these armoured dinosaurs from their Jurassic origins through to the very end of the Cretaceous the answer as to how some members of the Ankylosauridae developed that distinctive tail club may have finally been resolved.

According to research published in the academic publication “The Journal of Anatomy”, the fused tail came first and the bony club evolved later. Postdoctoral researcher Victoria Arbour (North Carolina State University and the North Carolina Museum of Natural Sciences), authored the report, a study she started when at the University of Alberta under the tutelage and guidance of renowned palaeontologist Professor Phil Currie.

Studying the Ankylosauridae Family

Victoria has spent a large part of her career studying the Ankylosauridae and she is viewed by Everything Dinosaur team members as the “go to” person when it comes to the ankylosaurids.

For example, back in October 2014, Everything Dinosaur reported on a new species assigned to the Ankylosauridae named by Victoria – Zaraapelta (Z. nomadis), fossils of which were found during an expedition to Mongolia led by Professor Currie.

To read more about Zaraapelta: Zaraapelta – In Praise of Victoria Arbour.

This new study involved examining the fossilised remains of some of the earliest known ankylosaurids, dinosaurs like the Chinese Liaoningosaurus from Yixian County, Liaoning Province (north-eastern China), as well as many Late Cretaceous forms.  An ankylosaur’s tail is composed of a handle and a bony knob.  The knob is comprised of fused osteoderms, a special kind of bone formed in the skin.  The handle is represented by the distal end of the tail (caudal vertebrae) that support the weight of the knob.

Commenting on the Study

Victoria explained:

“In order for an ankylosaur to be able to support the weight of a knob and swing it effectively, the tail needs to be stiff, like an axe handle.  For that to occur, the vertebrae along the tail had to become less flexible, otherwise the momentum generated by the knob’s weight could tear muscle or dislocate vertebrae.”

Gobisaurus – A 90-Million-Year-Old Ankylosaur

Tracing the tale of the Ankylosaurus tail.

Picture credit: Sydney Mohr

A Tale of Tails

Other ankylosaurids included in the analysis were Gobisaurus (Turonian faunal stage of the Cretaceous) and Pinacosaurus from the younger Campanian faunal stage of the Cretaceous.

Three Ways in Which the Ankylosaurid Tail Could Have Evolved

There are three ways in which the bony club and the fused, stiffened tail could have evolved:

1. Bony club first – early ankylosaurids would show evidence of osteoderms forming and enveloping the end of the tail
2. Handle first – primitive members of this family would have overlapping or fused tail bones
3. The club and handle could have evolved simultaneously, if this was the case, then Early Cretaceous ankylosaurids would show both anatomical features, perhaps with tails getting stronger and tail clubs getting heavier over time

How Did the Ankylosaurs Get their Unusual Tails?

Three different theories of ankylosaurid tail evolution.

Picture credit: Journal of Anatomy

Comparative Analysis

The comparative analysis revealed that by the Early Cretaceous, ankylosaurids had begun to develop stiff tails with fused caudal vertebrae.  The bony knob feature did not appear in the fossil record until the Late Cretaceous.

Dr Arbour concluded:

“While it’s possible that some of the species could still have developed the handle and knob in tandem,” it seems most likely that the tail stiffened prior to the growth of the osteoderm knob, in order to maximise the tail’s effectiveness as a weapon.”

The upshot of this conclusion is that ankylosaurs used their tails as defensive weapons first and then only later did the heavy club on the tail evolve.   Commenting on this work a spokesperson from Everything Dinosaur stated:

“This is a fascinating study, one can speculate that the bony club tail evolved in response to the emergence of bigger and more dangerous theropod predators such as the tyrannosaurids that could be regarded as the apex terrestrial predators in the Northern Hemisphere towards the end of the Mesozoic.”

The Tail Bones of Ankylosaurs

Caudal anatomy of ankylosaurs.

Picture credit: Journal of Anatomy

Tail Clubs

The picture above shows (A) an oblique dorsal view of the tail club of Dyoplosaurus acutosquameus from Canada, the fossils of which are around 76 million years old (Campanian).  This is typical of the derived Ankylosaurine tail  with a fused tail and a bony club.  Gobisaurus (G. domoculus) line drawing is (B) a left lateral view of this earlier ankylosaurid’s tail showing fusing of the bones.

Picture (C) shows the same fossil specimen as (B), but this time viewed from the other side, the deep groove running along the bottom is the haemal canal.  X-ray (D) and the interpretive drawing (E) are from an ankylosaur tail from Alberta, the last tail bone is small and rounded when compared to the long distal caudal bones.  Picture (F) shows two tail bones from Mymoorapelta maysi, a basal member of the Ankylosauria known from the Late Jurassic of the United States.

Typical of Nodosaurids and Basal Ankylosaurs

This anatomy is typical of nodosaurids and other basal ankylosaurs, the prezygapophyses (forward projecting points of bone located on the neural arch of the vertebrae), overlap the adjacent vertebrae by about 25% of the centrum (the main part of the vertebra situated below the neural arch).  In contrast, picture (G) shows the fossilised remains of Liaoningosaurus (L. paradoxus) which dates from the Aptian faunal stage making the fossil some 120 million years old.  The boxed area in (G) is highlighted and magnified (H).  In Liaoningosaurus the prezygopophyses overlap the preceding vertebra by at least 50% including a much more fused and stiffened tail, more typical of later ankylosaurids.

Ankylosaur Tail Club

 This research has provided new evidence to help scientists understand the evolution of ankylosaurid tails.  Fossils from China such as those of Liaoningosaurus suggest that the mechanism to support a tail club may have evolved at least forty million years before it was taken to extremes by the Late Cretaceous ankylosaurs such as Euoplocephalus and Pinacosaurus.  Early ankylosaurids evolved the handle first, those distal ossified osteoderms came later.

For models and replicas of armoured dinosaurs and other prehistoric creatures: PNSO Age of Dinosaurs.