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Plesiosaur Vertebrae from Lyme Regis

Plesiosaur Vertebrae United!

Having been on the Cumbrian coast last week as the last vestiges of hurricane Gonzalo battered the UK, our thoughts turned to elsewhere in the UK where strong winds and high tides might also be damaging the coastline.  One area we considered to be under particular threat was the Jurassic coast of Dorset.  The cliffs around Lyme Regis are very unstable and adverse weather conditions could lead to further rock falls and mud slides.  Ironically, our chum Brandon Lennon sent us some amazing pictures over the weekend of Plesiosaur dorsal vertebrae that had been found in the Lyme Regis area.  Not only is this fossil specimen very beautiful, but it seems behind every string of articulated vertebrae there is an interesting story…

Whilst visiting Lyme Regis for the Fossil Festival (May 2014), enthusiastic fossil hunter Chris East decided to try his luck and explore the beach west of Lyme Regis (Monmouth).  He found a Birchi nodule with signs of a fossilised bone encased within it.  Birchi nodules are rounded, calcareous concretions that can be found deposited in a thin layer above the shales with beef strata.  They are often associated with fossils, particularly Ammonites such as Microderoceras birchi.  Finding evidence of a bone, he thought it best if this specimen was professionally prepared and cleaned.  A very sensible idea, as once the rock had been cleaned and carefully prepared the nodule was seen to contain a row of beautifully preserved and articulated Plesiosaur vertebrae.

Plesiosaurs were a diverse group of marine reptiles that thrived during the Jurassic and Cretaceous.  There were two main types, the long-necked forms (Plesiosaurs) and the closely related, short-necked forms commonly referred to as Pliosaurs.

An Illustration of a Typical Jurassic Plesiosaur

An Illustration of a Plesiosaurus.

An Illustration of a Plesiosaurus.

Fossils of Plesiosaurs from Lyme Regis are much rarer than Ichthyosaurs, discovering this set of articulated vertebrae is an exceptionally rare find indeed.  Whilst in Lyme Regis earlier this month, Chris took the opportunity to show the vertebrae fossils to local fossil expert Brandon Lennon.  To Chris’s great surprise Brandon, on hearing where the Birchi nodule had been found, was able to add to his specimen.  Fossil expert Brandon, who regularly takes guided fossil walks onto Monmouth beach, had identified some Plesiosaur bones whilst exploring a recent mudslip on Monmouth beach.  Brandon was able to confirm that the isolated bones did come from the same individual Plesiosaur as the bones found by Chris East some months before.

The Plesiosaur Vertebrae Found by Brandon Lennon

Fossil specimen found by Brandon Lennon.

Fossil specimen found by Brandon Lennon.

Picture Credit: Brandon Lennon

Thanks to one local man’s expertise, the Plesiosaur fossil material was re-united.

The row of Articulated Plesiosaur Vertebrae

A row of 8 Plesiosaur vertebrae with associated ribs fragments.

A row of 8 Plesiosaur vertebrae with associated ribs fragments.

Picture Credit: Brandon Lennon

The beaches around the Dorset town of Lyme Regis can still yield such treasures. Storms over the winter months are likely to expose yet more fossil finds, however, we would urge caution as the frequent rock falls and mudslips from the unstable cliffs coupled with dangerous tides make this part of the coast no place for the inexperienced fossil hunter.  Our best advice is to go on a guided fossil walk with a local expert.  A fossil expert, such as Brandon Lennon, can show visitors the best (and safest) places to find fossils, you never know, you might just find a vertebra or two from a marine reptile.

For information on guided fossil walks: Lyme Regis Fossil Walks

Deinocheirus – Done and Dusted (For Now At Least)

Solving the Mystery of “Peculiar Terrible Hand”

Back in November 2013, team members at Everything Dinosaur wrote about of the most intriguing reports to come out of the annual Society of Vertebrate Palaeontology meeting that had just come to an end in Los Angeles.  As the dust settled and the researchers made their way home, here was a chance to reflect on the remarkable work done to help finally resolve a fifty year mystery.  What type of dinosaur was Deinocheirus?

Huge fossilised forelimbs and shoulder bones, discovered by a joint Polish/Mongolian expedition to the Gobi desert in 1965 had fascinated scientists for nearly half a century.  The arms were massive, measuring some 2.6 metres in length (including shoulder blades) and each hand ended in three-fingers, each finger tipped with an enormous, curved claw which in one case was over twenty centimetres long.

Based on these huge arms and a few other scraps of fossil bone, most palaeontologists agreed that the fossils represented a giant form of ornithomimid, a member of the “Bird  Mimic” group of Theropod dinosaurs.  Although the arms were much bigger, they did resemble the arms and hands of agile, fast running ornithomimids such as Struthiomimus and Dromiceiomimus.  A formal announcement was made about the discovery in 1966, and Deinocheirus “Terrible Hand” was described based on this holotype material in 1970.

This was the cue for every dinosaur book publisher to include a picture of the fossil material in virtually every dinosaur book produced in the seventies and eighties, although very few attempts to illustrate the dinosaur were actually made if we recall correctly.

The Holotype Fossils of Deinocheirus (Deinocheirus mirificus)

Fearsome arms of Deinocheirus

Fearsome arms of Deinocheirus

Picture Credit: Everything Dinosaur

The woman in the photograph is Professor Zofia Kielan-Jaworowska, the scientist who led the 1965 expedition.  Although the limbs have been repositioned and remounted since this picture was taken, it does provide a very good impression of the scale of those fossilised limbs.

Writing in the journal “Nature” the scientists behind the paper presented at the conference last year have revealed more about the “enigma” that is the Ornithomimosaur Deinocheirus mirificus.  Turns out that this bizarre Theropod is even more amazing than previously imagined.  In the journal, the scientists describe two new specimens of Deinocheirus that were discovered in the same formation (Nemegt Formation) as the original holotype material.  These much more complete fossil remains have enabled the researchers which include Phil Currie (University of Alberta), Yuong-Nam Lee and Hang-Jae Lee (Geological Museum, Korea Institute of Geoscience and Mineral Resources) as well as Pascal Godefroit (Royal Belgian Institute of Natural Sciences), to build up a comprehensive picture of what this dinosaur looked like, where it lived and what it ate.

A New Interpretation of Deinocheirus (D. mirificus)

A bizarre looking Theropod after all.

A bizarre looking Theropod after all.

Picture Credit: Yuong-Nam Lee/Korea Institute of Geoscience and Mineral Resources

It is certainly the largest member of the Ornithomimosauria known to science, with an estimated length of around 11 metres, several tonnes in weight and standing about as tall as a modern-day Giraffe, but it was no vicious super predator.  Studies of the feet and hind legs indicate that this animal was probably a slow walker, one with a huge pot belly to boot.  A pot belly?  This dinosaur had an expanded pelvis with strong muscle attachments.  It probably had a large gut to help it digest the tough plant material that it ate.  The skull measures over a metre in length, but there were no teeth in the deep jaws.  Indeed, over a 1,000 gastroliths have been found in association with the fossils, along with fish remains in the body cavity indicating that this animal was probably a mega-omnivore, eating plants, but also insects, small animals and fish.

Deinocheirus lived next to a large river.  Seventy million years ago, this part of Mongolia resembled the Upper Nile.  The broad, wide toes with their blunt claws were ideally suited to assist this animal when walking over soft mud. It probably wandered into the river to feed on soft water plants, to catch the occasional fish and to avoid the attentions of the Tyrannosaur Tarbosaurus.  However, evidence that Tarbosaurus fed on Deinocheirus has been preserved on some of the bones.  Whether or not the bite marks and feeding gouges that have been identified indicate that Tarbosaurus predated on these large bipeds, or whether these marks were made as a result of scavenging a carcase remains unclear.  However, the deep, “U-shaped” wishbone of this dinosaur and those big shoulder bones suggest that this ponderous giant could inflict some serious damage should any unwary tyrannosaurid venture too close to those huge arms.

This dinosaur had a number of unique skeletal features, it had a pygostyle (fused vertebrae on the end of the tail), like a bird and a much thicker tail than its smaller ornithomimid relatives.  Perhaps one of the most intriguing features are the large number of tall neural spines.  The dorsal and sacral vertebrae have flat, blade-like extensions (neural spines).  To us, these spatulate spines resemble the bones seen in the humps of Bison.  Deinocheirus could have had a sail-like structure on its back, or maybe even a large hump.  It has been suggested that the hump, originally reported upon in 2013, could have been exaggerated. These neural spines could have supported a network of ossified tendons to help support this dinosaur’s huge gut and heavy tail.

An Illustration of Deinocheirus (D. mirificus)

A mega-omnivore that had to watch out for Tarbosaurus.

A mega-omnivore that had to watch out for Tarbosaurus.

Picture Credit: Michael Skrepnick

The model making company Collecta introduced a 1:40 scale replica of the mysterious Deinocheirus back in 2012.  At the time, we commended them for bringing out a model of this dinosaur when so very little of the total skeleton had been studied and described.  With the information regarding the hump, we at Everything Dinosaur amended our scale drawing to give an impression of a small hump over the pelvis, but the latest illustrations really emphasis the hump or sail on this animal’s back.  Ironically, Collecta gave their Deinocheirus model feathers, no evidence of feathers on the original holotype material or indeed on the more recently discovered fossils have been found, but it is thought that a number of ornithomimids were indeed, feathered.

An Illustration of the Collecta Deinocheirus Model (2012)

Scientists speculate that Deinocheirus was covered in simple feathers.

Scientists speculate that Deinocheirus was covered in simple feathers.

As lead author of the scientific paper, Yuong-Nam Lee states the researchers were just as surprised as anyone when they put the complete dinosaur together based on the three main specimens that had been found to date.

Yuong-Nam Lee went on to add:

“The discovery of the original specimen almost half a century ago suggested that this was an unusual dinosaur, but did not prepare us for how distinctive Deinocheirus is.  A true cautionary tale in predicting forms from partial skeletons.”

To view Everything Dinosaur’s origin article on this research, published in November 2013: A Helping Hand for Deinocheirus

To view the range of Collecta scale models available including the 1:40 replica of Deinocheirus: Collecta Scale Models of Prehistoric Animals

Prehistoric Times Issue 111 Reviewed

A Review of Prehistoric Times (Issue 111) Autumn 2014

Summer may be over for us in the northern hemisphere and for the UK the clocks go back next week heralding some months when nights are going to be longer than days.  However, perfect fireside reading has arrived in the nick of time, in the shape of the latest edition of the quarterly magazine “Prehistoric Times” and once again it is jam packed with interesting articles, fantastic artwork and features.  Decorating the front cover is a beautiful rendering of a Cretaceous fight scene between an unfortunate Hippodraco (iguanodontid) and a mob of Utahraptors.  This artwork was created by the very talented Julius Csotonyi and inside this issue there is a super interview with the palaeo-artist and a review of his new book “The Palaeoart of Julius Csotonyi” by Julius and Steve White.  Everything Dinosaur team members were sent a copy of this hardback a few months ago, it really is an excellent book showcasing the talents of a remarkable artist.  The interview with Julius conducted by “Prehistoric Times’s” editor Mike Fredericks, is supported by lots of illustrations which show the range of prehistoric animals and time periods covered by Julius in his new publication.  The scene featuring several Late Cretaceous herbivores demonstrating “dietary niche partitioning” is my personal favourite, although my nephew likes the eyeball-plucking raptor best – still that’s kids for you.

The Front Cover Artwork (Prehistoric Times Issue 111)

Prehistoric Times magazine.

Prehistoric Times magazine.

Picture Credit: Prehistoric Times

One of the featured prehistoric animals is Baryonyx and there are oodles (scientific term), of great illustrations sent in by readers on this member of the Spinosauridae and we greatly appreciated the article by Phil Hore on this Theropod.  We too, like Phil, have speculated on how many fossil specimens ascribed to prehistoric crocodiles in the past may well turn out to be evidence of widely dispersed spinosaurids.  Special mention to our chum Fabio Pastori for a simply stunning Baryonyx drawing.

The magazine has a bit of an “English theme” running through it.  Dinosaur discoveries of southern England are documented in another article, which features the artwork of John Sibbick and there is a well written piece by John Lavas that discusses the impact of Sir Arthur Conan Doyle’s “Lost World”, a novel that we are informed has not been out of print since its publication back in 1912.  Bringing things right up to date, our review of “Dinosaurs of the British Isles” is featured, a book which documents and catalogues the Dinosauria known from these shores.

Tracy Ford continues his series on how to draw dinosaurs by discussing integumental coverings – feathers, quills and bristles on the Dinosauria.  He makes some excellent points and it is great to see a piece that features one of our favourite dinosaur discoveries of recent times, Kulindadromeus zabaikalicus.  This little feathered, plant-eating dinosaur makes another appearance in the Palaeo News section, along with updates on the Spinosaurus quadruped/bidped debate, giant prehistoric birds, a newly described Archaeopteryx specimen and a short report on Dreadnoughtus schrani .  Dreadnoughtus is important as a large number of bones have been found, helping palaeontologists such as Dr. Kenneth Lacovara (Drexel University), to estimate the body mass of this huge Titanosaur.  This dinosaur discovery adds a whole new dimension to body mass estimations using femora radii.  Everything Dinosaur wrote a short article on this discovery, it was favourably commented upon by the scientists behind the research paper and we basked in the glory of being praised by the researchers (for a few days at least).

To read more about “Prehistoric Times” and to subscribe: Prehistoric Times Magazine

Dan LoRusso is interviewed about his work on the Battat “Terra” model range and there is a special feature on the bizarre, sabre-toothed Thylacosmilus.  The “English” theme is re-visited once again with a fascinating article penned by Allen A. Debus which examines the way palaeontology was depicted in the popular press of the 19th Century, the list of references at the end of this article is especially helpful.  Amongst the many other features and news stories is an interview with Todd Miller, the director of the film all about the controversy surrounding the Tyrannosaurus rex named “Sue”, the thirteenth documented T. rex dinosaur discovery hence the film’s title “Dinosaur 13″.  We had the very great pleasure of meeting Pete Larson in London just a few weeks before the film’s August 15th premier.  Pete chatted about the documentary and Everything Dinosaur did some work on behalf of the media company responsible for the distribution of this excellent film in the UK back in the summer.

Ah well, summer may be over but at least we have another super edition of “Prehistoric Times” to keep us occupied over those long autumn evenings.

Those Plucky Placoderms

Armoured Fish Made a Significant Contribution to Vertebrate Evolution

The Placoderms were a hugely diverse and very successful group of fishes, whilst they lasted. For in terms of this groups’ persistence, in geological terms they make a relative short appearance in the history of life on Earth.  As a group the Placoderms were around for approximately sixty-five million years, not a bad innings but nothing like the longevity of other types of fish such as the sharks, rays and certain Actinistians, the Coelacanth for example.  The Placoderms, or to be more correct, the Class Placodermi first evolved in the Late Silurian and they disappear from the fossil record at the end of the Devonian Period.

Perhaps the most famous Placoderm is the giant predator Dunkleosteus.  Several species are known and with some specimens estimated to have reached lengths of around ten metres or more, at the time, (Dunkleosteus lived towards the end of the Devonian something like 370 – 360 million years ago), this fish would have been one of the largest vertebrates ever to have evolved.

Dunkleosteus – An Illustration

Fearsome marine predator of the Late Devonian.

Fearsome marine predator of the Late Devonian.

Picture Credit: Everything Dinosaur

Dunkleosteus may have looked like a typical Placoderm with its head and thorax covered in articulated armour plate, but the Placodermi, it turns out are being seen as one of the most important group of vertebrates to have existed  It is not just because they evolved into the likes of Dunkleosteus, regarded by many as the world’s first, vertebrate, super-predator, but this group of armoured fishes seems to have achieved a number of “firsts” in terms of the Chordata (animals with a spine or spine-like structure in their bodies).

Firstly, palaeontologists have found a number of fossils that suggest that early members of the Placodermi were amongst the first types of vertebrate to evolve a jaw.  Recently, Everything Dinosaur wrote a short article about a remarkable fossil discovery form China which reveals some remarkable features: A Jaw Dropping Discovery.

In addition, although the majority of Placoderms seemed to have been poor swimmers, with most of them living close to the bottom, a number of families were active and nektonic, indeed these types of fish were the first to evolve paired pelvic fins, a fishy equivalent of legs, although not connected with the spine.  Paired pelvic fins are an anatomical feature found in most types of extant fish today.

Those plucky Placoderms may have been amongst the first types of animal to develop teeth.  Recently a team of scientists from Australia and Bristol University studying fossilised remains of Placoderms from Western Australia found evidence of the first types of teeth, teeth with a structure very similar to our own.  To read more about this: The Origins of a Toothy Grin

Fossils from the same rocks (Go Go Formation) western Australia gave palaeontologists a remarkable insight into the reproductive strategies of many types of ancient fish.  One species of Placoderm, known from just a single fossil specimen represents the oldest example of a vertebrate capable of giving birth to live young (viviparity). Materpiscis attenboroughi was a small, bottom of the reef dwelling fish whose fossilised remains preserved in a limestone nodule showed evidence of an embryo and an umbilical cord.  This was evidence of internal fertilisation within the fossil record and the oldest known case of viviparity.

Materpiscis attenboroughi – A Remarkable Placoderm

Materpiscus means "Mother Fish".

Materpiscus means “Mother Fish”.

Picture Credit: Museum Victoria

The remarkable Placodermi may have just added another evolutionary “first” to their string of impressive attributes.   A scientific paper published in the journal “Nature” provides details on a fossil discovery that hints at the very first example of copulation amongst vertebrates.  The international team of researchers that led the study into the Antiarch (an-tee-arc) Placoderm called Microbrachius dicki state that this was the earliest animal known from the fossil record to stop reproducing by spawning (external fertilisation).

Professor John Long (Flinders University, South Australia), was the lead author of the academic paper.  The Professor, a renowned expert on Devonian fishes had earlier worked on Materpiscus attenboroughi.  The fossils of M. dicki are relatively common.  This small freshwater Placoderm grew to about ten centimetres in length and lived around 385 million years ago.

Professor Long Explains the Key Points of the Research

Studying Placoderms and other Devonian fish.

Studying Placoderms and other Devonian fish.

Picture Credit: Flinders University

Commenting on the research, Professor Long stated:

“We have defined the very point in evolution where the origin of internal fertilisation in all animals began.  That is a really big step.”

A close inspection of a fossil revealed that one of the Microbrachius specimens had a peculiar “L-shaped” appendage.  Further study revealed that this was the male fish’s genitalia.

The Professor pointed out:

“The male had large bony claspers, These are the grooves that they used to transfer sperm into the female”.

On the other hand, the females had a small bony structure at the rear that helped to lock the male organ in place during mating.  Constrained by the anatomy, the fish probably had to mate side by side, a sort of “square dance position” as described by the researchers.

An Illustration Showing the Proposed Mating Position of M. dicki

Mating "square dance" style.

Mating “square dance” style.

Picture Credit: Flinders University/Nature

However, copulation using this method does not seem to have stayed around for very long in these Devonian fish.  As fish evolved, they reverted back to external fertilisation (spawning), whereby male and females release sperm and eggs respectively into the water and fertilisation relies more on chance.  It took several more millions of years before the ancestors of today’s sharks and rays evolved copulation.

The Placodermi may be most famous for the likes of Dunkleosteus, but scientists are beginning to realise that these strange, armoured fish may have contributed much more to the evolution of the vertebrates than just the first, back-boned  super-predator!

Nosing Around Dinosaurs

New Study Sniffs Out Details of the Pachycephalosaur Nose

A study into the nasal passages conducted by a team of scientists from Ohio University suggests that certain types of dinosaur used their complicated noses to help cool their brains as well as to enhance their ability to smell.  The study, which focused on specimens from the Pachycephalosauridae family (the bone-heads), involved the development of computer models derived from CT scans of fossilised skulls in order to map the airflow in and out of a dinosaur’s snout.  Palaeontologists have known for some time that a number of different types of dinosaur had very complex nasal passages.  The nasal region although mostly associated with breathing (respiration), also plays an important role in helping to define and enhance a creature’s sense of smell.  In addition, the ability to bring in air at an ambient temperature into the skull may have a function in helping the brain to keep cool.  In the Late Cretaceous of North America, Pachycephalosaurs may have had small brains in their heavily armoured skulls but they did not want them to cook inside those thick heads.

A Model of a Typical Member of the Pachycephalosauridae Family

Nosing around the nasal passages of dinosaurs.

Nosing around the nasal passages of dinosaurs.

Picture Credit: Everything Dinosaur

Lead author of the research, which has just been published in the academic journal “The Anatomical Record”, Jason Bourke (Ohio University) states:

“Figuring out what’s going on in their [dinosaurs] complicated snouts is challenging because noses have so many different functions.  It doesn’t help that all the delicate soft tissues rotted away millions of years ago.”

In order to gain an appreciation of the nasal passages of long extinct dinosaurs, the team examined the snouts of extant relatives of the Dinosauria, namely birds, crocodiles and other reptiles including lizards.  The study of fossil skulls of Pachycephalosaurs was supported by lots of dissections, blood-vessel injections to map blood flow as well as CT scans.  The researchers also relied upon computer models that provided a three-dimensional analysis of airflow.

A technique more commonly applied to the study of airflow in the aerospace industry, a technique called computational fluid dynamics was used to better understand how extant animals such as Alligators and Ostriches breathe.

As PhD student Jason Bourke explained:

“Once we got a handle on how animals breathe today, the tricky part was finding a good candidate among the dinosaurs to test our methods.”

The team turned to a family of bird-hipped dinosaurs known as the Pachycephalosaurs, the bone-headed dinosaurs.  These particular dinosaurs were chosen as a number of specimens were readily available to study in the United States/Canada and skulls attributed to several genera were known.   The thick skulls with their ornamentation may have been used  by these relatively small dinosaurs for head-butting or visual displays.  The skull bones, some of which are several inches thick, has helped to preserve details of the nasal passages which the scientists were able to map and analyse in great detail.

Getting Up a Dinosaur’s Nose

Airflow in the nasal passages in the Pachycephalosaur Stegosaurus validum is mapped.

Airflow in the nasal passages in the Pachycephalosaur Stegoceras validum is mapped.

Picture Credit: Ohio University/The Anatomical Record

One Pachycephalosaur that was studied was Stegoceras (S. validum) and the researchers were able to show that some of the airflow that they mapped would have carried odours to the olfactory region, helping to improve this dinosaur’s sense of smell.  In addition, the team tried to piece together the shape of the nasal concha, otherwise known as the turbinates, that help to direct and manage airflow through the nasal passage.  This small bone, superficially resembles a sea shell (hence the name) and the fossil evidence supports the presence of such a bone but it is not found in the Dinosauria fossil record (as far as we at Everything Dinosaur know).  As the researchers point out, there is the bony ridge preserved on Pachycephalosaur skulls that indicate its presence and when airflow models were created, the best and most efficient ones produced included a turbinate structure within the model.

Commenting on the research results, Jason Bourke stated:

“We don’t really know what the exact shape of the respiratory turbinate was in Stegoceras, but we know that some kind of baffle had to be there.”

Study co-author Ruger Porter (Ohio University), pointed out that turbinates may well direct air to the olfactory region, but they might have also played another critical role, helping to cool the brain or at least helping to conserve moisture that might have been lost during exhalation.

Porter pointed out:

“The fossil evidence suggests that Stegoceras was basically similar to an Ostrich or an Alligator.  Hot arterial blood from the body was cooled as it passed over the respiratory turbinates and then that cooled venous blood returned to the brain.”

Whether this new research supports the theory that these dinosaurs were warm-blooded (endothermic) is being debated, but it does suggest there was more going on within dinosaur’s noses than scientists had previously thought.  It is hoped that the research team will be able to apply their analytical methods to other types of dinosaur such as the Thyreophora (armoured dinosaurs), known for their notoriously complex nasal passages.  This research may also provide answers to the questions concerning the bizarre shape of many crests found in Lambeosaurine dinosaurs (duck-billed dinosaurs).

Giant Kangaroos Made for Walking

Giant Sthenurine Kangaroos Probably Walked Rather Than Hopped

The Pleistocene prehistoric fauna of Australia may not quite be as embedded into the public’s consciousness as the Woolly Mammoths, Cave Bears and Sabre-Toothed Cats that represent examples of European Pleistocene prehistoric animals, but if anything, ancient “Aussies” were even more amazing than the shaggy coated examples typical of the fauna of the western hemisphere.  In a new study, published in the on line academic journal PLOS One (Public Library of Science), a team of researchers propose that ancient, giant Australian Kangaroos were walkers rather than hoppers, making up part of a prehistoric fauna that was truly astonishing.

The Kangaroos in question are the heavy-weight members of the Sthenurinae (the short-faced kangaroos).  A sub-family of the Macropodidae (means “big feet”), the family to which all Kangaroos belong.  Following a rigorous comparative analysis, the research team conclude that these large animals, some of which stood over two metres tall, did not hop but were adapted to a pedestrian lifestyle, these animals were walkers.  Sadly, like most of Australia’s mega fauna these herbivores became extinct and did not make it into the Holocene.  The last of the Sthenurinae died out about 30,000 years ago, shortly before the last of the Neanderthals in western Europe.

A Comparison Between an Extant Sthenurinae Kangaroo (Sthenurus stirlingi) and a Large Extant Species

Both these types of Kangaroo can stand up to two metres tall.

Both these types of Kangaroo can stand up to two metres tall.

Picture Credit: Wells and Tedford, 1995.  Original artist Lorraine Meeker, American Museum of Natural History, with additional annotation from Everything Dinosaur

As for reasons for their extinction, that question remains to be answered, however, it is thought that the presence of man on the continent from around 60,000 years ago had a severe impact on the fauna of Australia.  Giant Short-faced Kangaroos such as Simosthenurus occidentalis (short-faced, strong tail, western Kangaroo), known from fossils found in south-western Australia, probably could not move very quickly and could be caught by human hunters.  The use of fire could also have devastated their forest habitats leaving these browsers with little food.

The research team was led by Professor Christine Janis, (Professor of Ecology and Evolutionary Biology at Brown University, Rhode Island, USA).  Over one hundred comparative measurements were made, comparing the skeletons of living and extinct Kangaroo and Wallaby types.  For Professor Janis, her eureka moment occurred in 2005.  She was examining the bones of a mounted skeleton of a Sthenurine Kangaroo in a Sydney museum when she noticed how inflexible the spine looked when compared to a modern-day counterpart.  The professor began to wander whether these Pleistocene roos moved in the same way as extant Kangaroos.

Working in collaboration with the papers co-authors, Borja Figuerido of the University of Malaga (Spain) and Karalyn Kuchenbecker, a former undergraduate at Brown University, the Professor spent several years examining the fossilised remains of extinct Kangaroos to determine their method of locomotion.  In the published account of their studies, the team hypothesise that in their motion the extinct Sthenurines were very different from large Kangaroos found today.  The scientific paper is intriguing entitled: “Locomotion in Extinct Giant Kangaroos: Were the Sthenurines Hop-Less Monsters?”.

Extant Kangaroos can hop very quickly and utilise this unique form of motion to cover vast distances very efficiently.  They can also move about on all fours as their front limbs are capable of helping to support bodyweight, an anatomical characteristic absent in the larger members of the Sthenurinae.  The tail of many  members of the Macropodidae is also able to bear weight, providing additional support for many Kangaroos and Wallabies.  The use of the tail as a fifth limb has been referred to as a “pentapedal” stance.  Extinct Kangaroos such as Sthenurus stirlingi seem to lack the flexible spine need to make leaps and bounds.  Their anatomy seems best suited to putting one foot in front of the other – a walking Kangaroo!

Sthenurines had proportionally bigger hip and knee joints.  The shape of the pelvic area differs significantly as well (see diagram above).  The Sthenurines had a broad and flared pelvis that would have allowed for proportionally much larger gluteal muscles than other Kangaroos.  Those muscles would have allowed them to balance weight over just one leg at a time, as do the large gluteals of humans during walking.  Unlike modern Kangaroos with their four-toed feet, the extinct Sthenurines had just one, massive toe on the end of each foot.  The research team conclude that when the anatomy of all the Macropodidae is considered, the “weird” ones are the extant species that hop.  They are very lightly built for their size and their preferred method of locomotion may not be typical for the group as a whole.  A bit like using the Cheetah as a template for all Felidae motion.

Commenting on the research Professor Janis stated:

“If it is not possible in terms of biomechanics to hop at very slow speeds, particularly if you are a big animal and you cannot easily do pentapedal locomotion, then what do you have left?  You have to move somehow.”

An over reliance on walking, which is not as efficient as hopping, might explain the demise of these Kangaroos about 30,000 years ago.  These animals might have been easier to catch so humans took a toll on the population.  Or as the climate became more arid, these walking Kangaroos were not able to migrate far enough to find new sources of food.

An Artist’s Impression of a Short-Faced Kangaroo

Short-faced Kangaroo a pedestrian.

Short-faced Kangaroo a pedestrian.

Picture Credit: Brian Regal

The research team admit that more evidence is required to back up their anatomical study.  Ideally, if a set of “walking Kangaroo” tracks could be discovered, that would add considerable weight to their hypothesis.

Indonesian Cave Paintings Change Ideas About the Origin of Art

Oldest Prehistoric Cave Art in the World Perhaps – An Indonesian Cave Art Exhibition

The human ability to think in abstract terms is often cited as one of the key differences between our species and those in the rest of the animal kingdom.  Our love of art and visual depiction can be traced back to the Late Palaeolithic but the thought that since cave paintings are confined to France and Spain, therefore art began in Europe, has been challenged thanks to an amazing discovery on the Indonesian island of Sulawesi.

A joint Australian and Indonesian team of anthropologists have uncovered a series of ancient human hand stencils and paintings of animals in seven cave sites in the southern portion of Sulawesi island.  Although a rural location, these caves (Karst Maros) had been visited by a number of tourists and backpackers, but until now nobody knew just how old some of the paintings were.

A Number of Ancient Human Hand Stencils were Part of the Study

Ancient human "handy" work.

Ancient human “handy” work.

Picture Credit: Maxime Aubert

Archaeologists and palaeoanthropologists had long been puzzled by the appearance in southern Europe around 40-35 thousand years ago of a rich and varied range of artwork, including rock paintings and carved figures, but the absence or scarcity of similar art found elsewhere in the world.  Homo sapiens migrated into southern Asia and the Far East but little evidence of any form of culture in terms of works of art has been left behind on these migration routes.

Using a dating method that is based on the radioactive decay of uranium to thorium in small mineral growths that had formed on the paintings, the scientists were able to determine the minimum age of the paintings.  One hand stencil has been dated to circa 39,900 years ago, making it the oldest human hand print known to science.  A painting of a wild pig, an animal probably hunted by these ancient humans, has been dated to at least 35,400 years ago.  The artwork and images had been created by using red ochre, the materials and painting techniques used seem to be very similar to those found in caves of a similar age in western Europe.

Commenting on the significance of this study, Maxine Aubert of Griffith University (Queensland), one of the researchers stated:

“It was previously thought that Western Europe was the centre piece of a symbolic explosion in early human artistic activity such as cave painting and other forms of image making, including figurative art, around 40,000 years ago.”

This new research suggests that the rock art traditions seen on Sulawesi are at least as old as the oldest known European art.   One of the implications of this new study is that it has now been demonstrated that humans were producing very similar types of rock art by 40,000 years ago but at opposite ends of the Pleistocene Eurasian world.

The Oldest Human Hand Stencil and the Animal Drawing

Cave paintings at least 35,400 years old with hand stencils at least 39,900 years old.

Cave paintings at least 35,400 years old with hand stencils at least 39,900 years old.

Picture Credit: Maxime Aubert (green highlighting circles added by Everything Dinosaur)

The artwork is very faded in the above photograph, so we have circled in green the rock art that was studied.  It is feared, that just like the cave art in some European caves, modern pollution could damage these ancient Indonesian drawings.

To read an article about the damage being done to cave paintings in Europe due to rising levels of fungi: Cave Paintings Might Be Lost Forever

The scientists hope to use this radioactive dating technique to accurately date other rock art sites in Asia and Australia.  By doing this they hope to better understand human migration and the movement of abstract ideas through the ancient population as it migrated eastwards.

From Dinosaur Arms to the Wings of Birds

New Study Helps to Explain How Dinosaurs Got their Wings

Most scientists now agree the feathers originated in the Dinosauria and that Aves (birds) are descendants from a group of bipedal, very bird-like dinosaurs that make up a portion of a larger group of dinosaurs known as the Theropoda.  In essence, the birds we know today evolved from dinosaurs (specifically the Maniraptora).  However, despite a lot of fossil evidence to indicate that the birds are closely related to and descended from the Dinosauria there have been one or two areas that have led to some confusion.  Take for example, the wrist bones.  The numerous wrist bones in dinosaurs and their relatively immobile wrists evolved over time into the highly flexible wrists with fewer bones that scientists see today in living birds.  The wrist bones in birds helps to manage the forces involved in the movements of the wing in flight.  They also permit the wings to be folded back when the bird is not flying, so how the wrist bones of dinosaurs evolved into the specialised and highly modified wrist bones of birds has been the subject of much debate.

The Evolution of a Wrist Designed for a Wing

The evolution of a wrist bone adapted to flight.

The evolution of a wrist bone adapted to flight.

Picture Credit: Davide Bonnadonna

A new study by a team of scientists based at the Universidae de Chile (University of Chile), Santiago, Chile and published in the academic journal PLOS Biology may have solved this palaeontological puzzle.

Nine into Four Does Go

Let’s start with a very simple explanation of the problem.  Scientists studying living species, in this case birds and specifically ducks, chickens, lapwings, finches and budgerigars that were used in this study, can examine in minute detail the living organism.  They can also study embryos to see how the bones in the wrist are formed.  The scientists can also study the wrist bones and embryos of reptiles such as caiman to provide data on the wrist bones and embryonic growth of other types of Archosaurs.  The Archosauria is the Division of Reptilia that contains the dinosaurs and crocodiles, it is from the Archosaurs that the birds evolved.  These scientists can see how the anatomy of an animal develops.  Techniques such as cell and molecular biology studies can reveal all sorts of information with regards to how the wrists of extant (living organisms) form.  Palaeontologists, on the other hand, (no pun intended) only have a very incomplete fossil record to study.  So scientists are using different data sources to study wrist bone evolution.

Research to help identify the wrist bones in dinosaurs and the corresponding bones in the wrists of birds draws data from two radically different sources:

  • cell biology, extant organisms and embryology
  • fossils of birds, fossils of dinosaurs, studies of the bones of extinct animals

This new study shows how the modern bird wrist with its four bones, arranged in an approximate square shape corresponds to the nine bones found in non-avian dinosaurs.  The team have looked at how dinosaur wrists evolved and report on previously undetected evolutionary processes including loss, fusion and in one case, a re-evolution of a bone once lost in the Dinosauria.

A Critical Advance in Understanding

This new study effectively combined these two areas of research.  The laboratory run by Alexander Vargas (University of Chile) and lead author of the study, developed a new method of looking at specific proteins in the embryos and produced three-dimensional maps to demonstrate how the wrist bones formed.  This new method has been named whole-mount immunostaining.  It allows scientists to observe skeletal development in embryos much better than before.  At the same time, the research team re-examined the fossils of dinosaurs and prehistoric birds in a bid to tie the two strands of research together.

The Semilunate Bone

Back in the 1960′s the palaeontologist John Ostrom, re-ignited the bird/dinosaurs debate by proposing that fearsome, sickle-clawed predators such as Deinonychus (D. antirrhopus) were agile, active animals and very bird-like.  He proposed that the semilunate bone, one of the four bones making up the square-shaped arrangement of bones in a modern bird’s wrist had actually formed from the fusing of two bones present in dinosaur fossils, such as those bones found in the wrists of dinosaurs like Deinonychus and its relatives.  This new technique, confirms that Ostrom was right.

Deinonychus Part of the Dinosaurs to Birds Story

A fearsome Deinonychus dinosaur

A fearsome Deinonychus dinosaur

Picture Credit: Everything Dinosaur

Whole-mount immunostaining and the mapping of cartilage formation and proteins in the embryos of birds, allowed the scientists to confirm that the semilunate in Aves does form from as two separate cartilages which fuse and ossify into a single bone, proving that Ostrom was very probably on the right track nearly fifty years ago.

Dr. Vargas explained:

“These findings eliminate persistent doubts that existed over exactly how the bones of the wrist evolved and iron out arguments about wrist development being incompatible with birds originating from dinosaurs.”

This research has helped scientists to work out how the nine bones found in the wrists of some Theropod dinosaurs gradually evolved into the four bones seen in modern birds.  In addition, this study produced a surprise, a result that was not expected.  A small bone present in the wrists of a group of dinosaurs known as the Sauropoda, disappeared in the bipedal Theropods, but re-evolved when some Theropods began to fly.

Sauropods and Theropod dinosaurs are closely related.  They represent the two types of dinosaur that make up the Saurischia (lizard-hipped dinosaurs).  Sauropods walked on all fours and had a small bone in their wrist called the pisiform that had a function in their four-legged, quadrupedal stance.  Theropod dinosaurs were essentially bipeds (walking on their hind limbs).  The arms of these dinosaurs were no longer used for walking but for catching and subduing prey.  Over millions of years the pisiform bone was lost from the wrists of the two-legged Theropods.  However, the authors of this study discovered that the pisiform had reappeared in early birds, probably as an adaptation for flight, where this small wrist bone permits the transmission of force on the down-stroke of a wing beat whilst restricting flexibility on the up-stroke phase of a wing beat.

The Evolution of the Wrist from Dinosaurs to Birds

From

From dinosaurs to birds ( Dinosauria – Theropoda – Maniraptora – Aves)

Picture Credit: PLOS Biology

The chart shows the colour coded bones and how they changed over time.  For example, the pisiform bone (red) can be found in the Early Jurassic Ornithopod Heterodontosaurus (not a Theropod) and in the Late Triassic Theropod Coelophysis.  This bone is lost in later Theropods such as Allosaurus and Guanlong but evolves again in primitive birds such as Sapeornis.  Sapeornis was about the size of a seagull, it seems to have been a strong flyer.  It lived during the Early Cretaceous.

The colour coded chart also shows how the square-shaped arrangement of bones in a modern bird such as the chicken evolved, with the fusion of the distal carpal 1 and the distal carpal 2 bones (yellow and green).  In the Maniraptoran Falcarius, a member of the Therizinosauroidea and not a direct ancestor of birds, these two bones are distinct.  However, in those Maniraptorans believed to be more closely related to the birds, indeed, the ancestors of Aves, dinosaurs such as Khaan, Deinonychus and Yixianosaurus these two carpals become fused to form the semilunate found in the wrists of modern birds.

WIN, WIN with Everything Dinosaur

Competition Time Again with Everything Dinosaur

It’s competition time again with Everything Dinosaur and we have a signed copy of a fantastic new book all about British dinosaurs to win.  To celebrate the publication of “Dinosaurs of the British Isles” one of the authors of this amazing account about all things Dinosauria, palaeontologist Dean Lomax, has autographed a copy from the very first print run.  Everything Dinosaur is going to give this away to one lucky dinosaur fan.

The Front Cover of “Dinosaurs of the British Isles”

A comprehensive guide to British dinosaurs over 400 pages.

A comprehensive guide to British dinosaurs over 400 pages.

Picture Credit: Siri Scientific Press

This unique publication catalogues all the major dinosaur fossil discoveries from the British Isles.  With a foreward from Dr. Paul Barrett of the Natural History Museum, Dean and his fellow author Nobumichi Tamura provide a comprehensive account on the dinosaurs of the entire British Isles.  With hundreds of photographs, detailed skeletal reconstructions and vivid life illustrations this is a “must have” for every dedicated dinosaur fan, fossil collector and budding palaeontologist.

Competition Details

So our competition is this, if you were to discover a new species of dinosaur in the UK – what name would you call it?  That’s right, we want you to come up with a name for a new species of British dinosaur!

To enter our “name a British dinosaur” competition, a chance to win this truly unique account of the dinosaurs of the British Isles, all you have to do is “Like” Everything Dinosaur’s FACEBOOK page, then leave a comment with your suggested name for a new British dinosaur on the picture of the front cover of  the book (shown above).

Click the logo to visit our Facebook page and to give our page a "like".

Click the logo to visit our Facebook page and to give our page a “like”.

Everything Dinosaur on FACEBOOK: “LIKE” Our Facebook Page and Enter Competition

We will draw the lucky winner at random and the British dinosaur name competition closes on Friday, 31st October 2014.  Good luck to everyone and we can’t wait to see what British dinosaur names you come up!

Terms and Conditions of Name a British Dinosaur Competition

Automated entries are not permitted and will be excluded from the draw.

Only one entry per person.

The prize is non-transferable and no cash alternative will be offered.

The Everything Dinosaur name a British dinosaur competition runs until Friday, October 31st 2014.

Winner will be notified by private message on Facebook or email.

Prize includes postage and packing.

For full terms and conditions contact: Contact Us

To read Everything Dinosaur’s Review of “Dinosaurs of the British Isles”: “Dinosaurs of the British Isles” Reviewed

Can’t wait to get hold of this book!  ”Dinosaurs of the British Isles” can be ordered from Siri Scientific Press: Visit the website

New Armoured Dinosaur from New Mexico

Ziapelta sanjuanensis  From New Mexico but Closely Related to Canadian Ankylosaurs

For some strange reason, the Ankylosaurs don’t seem to be held in quite the same awe as the horned dinosaurs by most members of the public.  We at Everything Dinosaur have our own theory about this.  The horned dinosaurs are much easier for the lay person to recognise.  There is the spectacular spiked frill of Styracosaurus, the peculiar nasal boss of Pachyrhinosaurus, a dinosaur genus which came to greater prominence with the “Walking with Dinosaurs in 3-D” movie.  Then there is of course, the most famous horned dinosaur of all – Triceratops (three horned face).  Members of the Ankylosauridae tend to have the same basic body plan.  They have broad rumps, bony clubs on the end of their tails and of course, all that body armour.  Model makers often find it difficult to distinguish different armoured dinosaurs.  For example, the Saichania replica made by Schleich, to the uninitiated, resembles Ankylosaurus.

The Saichania Model made by Schleich

Saichania means "beautiful"

Saichania means “beautiful”

Picture Credit: Everything Dinosaur

When it comes to films and television documentaries, the Ankylosaurs are rarely given star billing.  So today, in our own small way, we are going to champion the Late Cretaceous armoured dinosaurs by discussing the newest member of their family – Ziapelta, from the San Juan Basin of north-western New Mexico.  The fossils of Ziapelta consist of elements of the skull and incomplete neck rings of spiky bone and fragments of the famous, scaly Ankylosauria body armour (osteoderms).  The material was discovered in 2011 by Robert Sullivan, subsequently excavated by Dr. Sullivan and colleagues and then stored at the New Mexico Museum of Natural History and Science.  Once extracted from its silt and sandstone matrix, the scientists had enough fossil evidence to assign these fossils to a new genera.  A thorough exploration of the surrounding area produced no further post-cranial material.  It seems the head and neck of this armoured dinosaur were separated from the rest of the body prior to burial.  How this came about, one can only speculate.

The fossils were collected from the De-na-zin Member of the Kirtland Formation which as been dated to around 74 to 72 million years ago.  At perhaps as much as six metres long, the herbivorous Ziapelta would have been a very formidable adversary for even the largest tyrannosaurid.

An Illustration of Ziapelta (Z. sanjuanensis)

New Armoured Dinosaur from New Mexico

New Armoured Dinosaur from New Mexico

Picture Credit: Sydney Mohr

To the lay person, the spiky-looking Ziapelta might just look like any other Ankylosauridae, so let’s explain why the skull and neck material have allowed scientists to erect a new genus of armoured dinosaur.  Firstly, elements of the skull have been found, the skull morphology (shape) and composition can be very helpful when looking to identify an animal new to science, dinosaurs included.  Co-author of the scientific paper, which is published in the on line academic journal PLOS One, Victoria Arbour commented:

“The horns on the back of the skull are thick and curve downwards and the snout has a mixture of flat and bumpy scales – an unusual feature for an ankylosaurid.”

Dr. Arbour (University of Alberta) is a renowned expert on all things Ankylosaur, she was invited to examine the fossils along with PhD student Mike Burns (University of Alberta).  The scientists concluded that unlike the armoured dinosaur Nodocephalosaurus kirtlandensis, which is also known from the San Juan Basin and is believed to be related to Asian genera of the Ankylosauridae, Saichania for example, Ziapelta was more closely related to the ankylosaurids of Canada.

The Formidable Spiky Cervical Rings of Ziapelta

Bony and spiky neck armour of Ziapelta.

Bony and spiky neck armour of Ziapelta.

Picture Credit: PLOS One

Dr. Arbour stated:

“Bob Sullivan, who discovered the specimen, showed us pictures and we were really excited by both its familiarity and its distinctiveness.  We were pretty sure right away we were dealing with a new species that was closely related to the Ankylosaurs we find in Alberta.”

Ziapelta has another unusual feature that distinguishes it from other ankylosaurids, a feature that we at Everything Dinosaur find quite endearing considering the size and fearsome nature of these reptiles.  The layout of the scales that make up the top of the skull are often very distinctive.  In the case of Ziapelta, it has a large triangular-shaped scale on the tip of its snout, in contrast to many other ankylosaurids which have a six-sided scale on their snouts

Views of the Skull Fossil of Ziapelta (Z. sanjuanensis)

Views of the skull fossil material of Ziapelta.

Views of the skull fossil material of Ziapelta.

Picture Credit: PLOS One

The photograph above shows various views of the holotype skull material, A – dorsal view (view from the top), B = ventral view (viewed from underneath), C = anterior view (view from the front), D = occipital view (viewed from the rear) and finally E – left lateral view (view of the left side of the skull).  In photograph A, we have highlighted in red the outline of that large triangular scale on the snout (referred to as mnca - median nasal caputegulum to use the formal scientific term).

Dr. Arbour put it very succinctly stating:

“There’s also a distinctive large triangular scale on the snout, where many other ankylosaurids have a hexagonal scale.”

The University of Alberta scientist has specialised in studying Ankylosaurs, especially those specimens which are known from the Late Cretaceous of North America.  Back in 2013, Everything Dinosaur reported on Dr. Arbour’s research into the Ankylosauridae which was helping to redefine this family of dinosaurs.

To read more about this research: When is a Euoplocephalus a Euoplocephalus?

Ankylosaurid fossils make up a small, but significant proportion of the Dinosauria fossil assemblage of southern Alberta, but to date, no ankylosaurid material has been found in the Horseshoe Canyon Formation (lower parts of this formation, the Strathmore and the Drumheller Members) of Alberta.  These rocks are roughly the same age as the strata in which the fossils of Ziapelta were found.  This New Mexico armoured dinosaur is helping palaeontologists to plug a gap in the record of ankylosaurid fossils known from North America.

Dr. Arbour explained:

“The rocks in New Mexico fill in this gap in time, and that’s where Ziapelta occurs.  Could Ziapelta have also lived in Alberta, in the gap where we haven’t found any Ankylosaur fossils yet?  It is possible, but in recent years there has also been increasing evidence that the dinosaurs from the southern part of North America – New Mexico, Texas and Utah, for example, are distinct from their northern neighbours in Alberta.”

There is a lot of evidence to support the idea of “dinosaur provinciality” in North America.  It seems that although the overall mix of dinosaurs was about the same in the regions, the actual genera that made up the dinosaur populations differed markedly.  How or why these distinct faunas came about remains something of a mystery.  The discovery of Ziapelta may help to add more pieces to the picture as palaeontologists strive to solve this puzzle.

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