Category: Dinosaur and Prehistoric Animal News Stories

Cretaceous “Big Mouths”

Cretaceous Fish with Gigantic Mouths

The oceans of the Cretaceous had some very strange inhabitants, sadly the fossil record only hints at the remarkable diversity of vertebrates, particularly fish.  That’s why when scientists announce the discovery of not one but two new species of Cretaceous plankton-feeding fish, such stories tend to make extensive ripples in palaeontological circles.  An international team of researchers have announced a tripling of the known fish species that make up the genus called Rhinconichthys (pronounced rink-oh-nik-thees).  New fossil discoveries from the United States and Japan extend the known distribution of these Cretaceous fish and it is likely that these types of animals had a global distribution during the Late Cretaceous.

An Illustration of a Pair of Rhinconichthys Fish Feeding

Large filter-feeding fish of the Cretaceous.

Large filter-feeding fish of the Cretaceous.

Picture Credit: Bob Nicholls

One of the lead authors of the study, published in the academic journal “Cretaceous Research” Kenshu Shimada, explained that fossils of these types of fish are exceptionally rare.  Previously, only one species was known Rhinconichthys taylori, and only two specimens had been described, both from England (dating from the Cenomanian faunal stage of the Cretaceous).  However, a new skull from Colorado, along with the re-examination of another skull found in Japan have extended the known palaeogeographical range along with the number of species.

Only the skulls have been found, the cartilaginous skeletons of these fish have a poor fossil preservation potential, a problem that has plagued scientists as they strive to piece together the history of plankton feeding fish.  For example, giants are known from the Jurassic such as Leedsichthys and it is very likely that a myriad of forms existed during the Mesozoic, but little fossil evidence has been found with regards to these creatures (Pachycormiformes).

To read more about research into ancient members of the Pachycormidae: Filling a 100 Million Year Wide Gap

The Colorado fossil was found by Bruce A. Schumacher (United States Forest Service), this species has been named Rhinconichthys purgatoirensis.  It dates from later in the Cretaceous when compared to the English fossils (middle Turonian faunal stage of the Cretaceous).  R. purgatoirensis swam in the Western Interior Seaway around 89 million years ago, whereas Rhinconichthys taylori lived at least five million years earlier.  The Japanese specimen found on the island of Hokkaido, dates from around the same time as the English fossils.  It has been named Rhinconichthys uyenoi.

Kenshu Shimada (Department of Environmental Science and Studies, DePaul University, Chicago) stated:

“I was in a team that named Rhinconichthys in 2010, which was based on a single species from England, but we had no idea back then that the genus was so diverse and so globally distributed.”

Rhinconichthys spp. are estimated to have ranged in size from 2 metres to more than 2.7 metres in length.  They had a highly specialised jaw with a pair of bones (called hyomanidbulae) that formed a huge oar-shaped lever that enabled the jaws to open extremely wide, a little like the opening mechanism for a parachute.  This enabled them to capture even more plankton as they swam.  This type of anatomical feature is also found in many types of filter feeding shark today, an example of convergent evolution.

A Picture of the Colorado Specimen Showing Jaw Bones with Explanatory Diagram

Able to open the jaws really wide.

Able to open the jaws really wide.

Picture Credit: DePaul University

Many More Suspension Feeders Existed

Feeding on plankton, being planktivorous, also known as suspension-feeding is seen in a number of specialised aquatic vertebrates today, including the largest animal known to science the Blue Whale (Balaenoptera musculus) and the largest extant fish the Whale Shark (Rhincodon typus).  Indeed, the genus name Rhinconichthys means “fish like a whale shark”.

Professor Shimada concluded:

“Based on our new study, we now have three different species of Rhinconichthys from three separate regions of the globe, each represented by a single skull.  This tells just how little we still know about the biodiversity of organisms through the Earth’s history.  It’s really mindboggling.”

Australopithecus sediba – Jaw Study Suggests a More Delicate Bite

Australopithecus sediba – Bio-mechanical Study Hints at Diet

South Africa might be regarded by many as the “cradle of humanity”, thanks to the wealth of Australopithecus and early hominin fossils found in that part of the world.  Thanks to a collaborative research effort involving a bio-mechanical study of skull strength and bite forces, it seems that further light is being shed on the diet of one of southern Africa’s most famous early residents Australopithecus sediba.  This new research may help palaeoanthropologists to further refine the evolutionary position A. sediba in relation to the hominins and ultimately this Australopith’s relationship to our own species.

H. sapiens Compared to A. sediba and Pan troglodytes (Chimpanzee)

A. sediba is in the middle, the human to the left of the picture with the chimp skeleton on the right.

A. sediba is in the middle, the human to the left of the picture with the chimp skeleton on the right.

Picture Credit: University of Witwatersrand

Fossils which came to be known as A. sediba were discovered in 2008 at the famous dig site of Malapa in the Cradle of Humankind World Heritage Site, located around thirty miles north-west of the city of Johannesburg.  Research published in 2012 suggested that this gracile, possible early human ancestor, had lived on a eclectic woodland diet including hard foods mixed with tree bark, fruit, leaves and other plants.  Other research, reported upon by Everything Dinosaur in 2013, provided further insight into the dietary habits of early hominins.

To see the article on research into early hominin diets: From a Forest Diet to a Savannah Smorgasbord

To read an article explaining how A. sediba came to be named: South African “Cradle Fossil” Named

This new study carried out by an international team of researchers, including Professors Lee Berger and Kristian Carlson from the Evolutionary Studies Institute (ESI) at the University of the Witwatersrand, now shows that Australopithecus sediba did not have the jaw and tooth structure necessary to exist on a steady diet of hard foods.  This may have important implications on how this species of Australopith is viewed in terms of its evolutionary link to that line of hominins that eventually led to our own kind.

Bio-mechanical Study Indicates that A. sediba Did Not Have “Nutcracker Jaws”

Bite Force Study on A. sediba cranium.

Bite Force Study on A. sediba cranium.

Picture Credit: Image of MH1 by Brett Eloff provided courtesy of Lee Berger (University of the Witwatersrand).

The picture above show the fossilised skull of A. sediba (specimen number MH1) and a finite element model of the skull depicting strains experienced during a simulated bite on the its back teeth (premolars).  “Warm” colours indicate high mechanical strain, whilst “cool” colours indicate areas of low strain on the skull.

Commenting on the research, published today in the scientific journal “Nature Communications”, Professor David Strait (Washington University, St Louis, USA) stated:

“Most Australopiths had amazing adaptations in their jaws, teeth and faces that allowed them to process foods that were difficult to chew or crack open.  Among other things, they were able to efficiently bite down on foods with very high forces.”

Co-author Dr Justin Ledogar, researcher at the University of New England in Australia added:

“Australopithecus sediba is thought by some researchers to lie near the ancestry of Homo, the group to which our species belongs, yet we find that A. sediba had an important limitation on its ability to bite powerfully; if it had bitten as hard as possible on its molar teeth using the full force of its chewing muscles, it would have dislocated its jaw.”

Not Biting Off More Than It Could Chew

Bio-mechanical modelling based on a computer generated replica of the fossil skull material does not provide conclusive evidence that Australopithecus sediba was on the direct evolutionary line towards Homo, but it does indicate that dietary changes were shaping the evolutionary paths of early human species.  The data acquired from the bio-mechanical analysis does not dispute the possibility that A. sediba occasionally ate hard foods such as nuts and bark.  However, limitations on the amount of bite force that the skull could withstand suggests that hard foods needing to be processed with high bite forces were not an important component of the diet of this species.

About Australopithecus sediba:

Australopithecus sediba, a diminutive pre-human species that lived about two million years ago in southern Africa, has been heralded as a possible ancestor or close relative of Homo, our own family.  Australopiths appear in the fossil record about four million years ago, and although they have some human traits such as the ability to walk upright on two legs, most of them lack other characteristically human features such as a large brain, flat faces with small jaws and teeth, and advanced use of tools.  Humans, members of the genus Homo, are almost certainly descended from an Australopith ancestor, and A. sediba is a candidate to be either that ancestor or something similar to it.

Dr Justin Ledogar explained:

“Humans also have this limitation on biting forcefully and we suspect that early Homo had it as well, yet the other Australopiths that we have examined are not nearly as limited in this regard.  This means that whereas some Australopith populations were evolving adaptations to maximise their ability to bite powerfully, others (including A. sediba) were evolving in the opposite direction.”

Foods that were important to the survival of Australopithecus sediba probably could have been eaten relatively easy without the need for high bite forces.

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

The Wildebeest and Lambeosaurine Connection?

Ancient Beast “Honked Like a Hadrosaur”

Convergent evolution throws up strange bedfellows from time to time.  Scientists studying an ancient bone bed have uncovered extensive fossil material from an ancient wildebeest that shows that this hoofed mammal had a raised nasal dome, reminiscent of a hollow crested duck-billed dinosaur.  Researchers have suggested that the bizarre anatomical structures helped these herd animals communicate more effectively.  It’s a question of what evolution did for the likes of Corythosaurus some 75 million years ago has been repeated in a Pleistocene bovine from around 75,000 years ago.

A Trumpeting Wildebeest – Rusingoryx atopocranion

Honking to communicate in the hot savannah.

Honking to communicate in the hot savannah.

Picture Credit: Todd Marshall

The ancient ungulate (hoofed mammal), was poorly known until a bone bed containing the remains of at least twenty-four individuals was discovered on Kenya’s Rusinga Island.  The fossilised remains, which includes juveniles as well as adult animals, has enabled scientists to piece together a much more comprehensive picture of the anatomy of this grazing mammal, part of a diverse African bovine fauna that flourished on the hot, dry savannah of southern Africa during the Pleistocene Epoch.

Stone tool marks on the bones indicate that these animals were butchered and it has been suggested that Middle Stone Age people had driven the animals into a river and ambushed them, or perhaps, a tribe benefited from a chance discovery of a group of these creatures who had recently drowned in a flood event.

Hollowed-out Headgear

The wildebeest is known as Rusingoryx atopocranion, but until now it had only been known from partial remains, including incomplete skulls.  The Rusinga excavation, supported by the National Geographic Society’s Committee for Research and Exploration has uncovered a total of six skulls, most of them complete.  Thanks to these fossils, scientists have a much better idea of what these animals actually looked like.

Commenting on the new evidence, lead author of the study, Haley O’Brien (Ohio University) stated:

“The first time I saw them my jaw completely dropped”.

Previous studies based on much less complete fossil material had speculated that Rusingoryx possessed a proboscis, but the new skulls discount this idea.  Instead, they reveal that R. atopocranion had a high nasal dome in front of its eyes, a sort of “cow with a Roman nose”.  The raised naris was hollow, encasing a winding, circuitous nasal passage.

The Skull of Rusingoryx (R. atopocranion)

The dome shaped skull (raised nasal bones).

The dome shaped skull (raised nasal bones).

Picture Credit: Haley O’Brien

PhD student Haley explained:

“There aren’t any living animals with a nasal apparatus like this, but there are some fossil ones.  Outside and in, the nose of Rusingoryx resembles the hollow crests of the “duck-billed” dinosaurs, animals like Corythosaurus and Lambeosaurus, which lived about 75 million years earlier.  Both groups essentially push the nasal part of their airway into the crest and they’re using similar suites of bones to form the crest itself.”

The Skull of the Mexican Lambeosaurine Velafrons (Velafrons coahuilensis)

Raised nasals - an example of convergent evolution.

Raised nasals – an example of convergent evolution.

Picture Credit: Paul Fraughton/Salt Lake Tribune

Commenting on the similarities between Rusingoryx and Late Cretaceous duck-billed dinosaurs, palaeontologist David Evans (Royal Ontario Museum, Toronto), stated that he was “blown away” by the skulls of Rusingoryx, he added:

“The resemblance between Rusingoryx and some hollow-crested dinosaurs in the form of the nasal structures is truly striking.”

Convergent Evolution

The dome shaped nasal area of Rusingoryx is an example of convergent evolution, whereby unrelated organisms evolve independently similar features, such as the streamlined bodies and tail flukes of dolphins and ichthyosaurs.  These are adaptations to similar habitats or ecological niches.

However, faced (no pun intended), with this strange-faced wildebeest, the big question is what sort of function did these domed noses have?

A number of ideas have been put forward:

  • The expanded naris played a role in cooling or warming incoming air

The large nose of Rusingoryx may certainly have been able to undertake this function and all mammals have some ability to do this, thanks to scroll-like bones called turbinates that increase the surface area of the nose.  As Rusingoryx lived in a very hot, dry environment this theory is plausible, but the dome’s internal anatomy did not support this conclusion.

  • The raised domes were used in ritual combat

A number of bovines use their skulls as battering rams to settle disputes and as defensive weapons.  However, the skull bones of Rusingoryx are very thin, much thinner than those of extant Artiodactyls (even-toed hoofed mammals) that indulge in such behaviour.

  • The nasal area acted as a resonating chamber for sound

Social, hoofed, herd-dwelling herbivores tend to be quite vocal.  They have ways to modulate their vocal tracts to increase the variety and range of sounds that they can make.  The skull anatomy suggests that the big dome-faced wildebeest used this structure to vocalise.

Student O’Brien explained:

“We calculated a frequency of between 250 and 750 hertz, which is not only pretty low, it also overlaps with the sonic frequencies of a vuvuzela.  Rusingoryx could very likely make a low trumpeting sound but there’s a good chance it could also vocalise in stealth mode.”

Being able to communicate at a low frequency making it difficult for some predators to hear, has a distinct evolutionary advantage, human hunters for example would have had difficulty picking up these sounds.  In addition, a herd of these animals would have been capable of making a lot of noise, much like a stadium full of South African football fans waving their vuvuzelas.

Duck-Billed Dinosaurs – Sweet Home Alabama!

Alabama Fossil Sheds Light on the Origins of Duck-Billed Dinosaurs

The Duck-Billed dinosaurs, or to be more precise, the Hadrosauroidea were a super-family of plant-eating, bird-hipped dinosaurs that dominated Late Cretaceous ecosystems throughout most of the northern latitudes.  The fossils of these large dinosaurs, some of which evolved into the biggest facultative bipeds known to science, can be seen in museums throughout the world, but little is known about the evolutionary origins of this very successful part of the Dinosauria.  However, a remarkable fossil find from Alabama (south-eastern United States), is helping to shed new light on the origins of the duck-billed dinosaurs.

The Fossils of Eotrachodon orientalis Laid Out

The skull and jaw bones including the predentary are nearest the camera.

The skull and jaw bones including the predentary are nearest the camera.

Picture Credit: Jun Ebersole, McWane Science Centre

The beautifully preserved fossils were found by amateur fossil hunters exploring a creek in Montgomery County, Alabama, when they come across one of the bones eroding out of the soft marine sediment.  Thanks to the efforts of an international team of researchers, the fossil material has been carefully prepared and it has been confirmed that these bones and the few teeth (see bottom right hand corner of the photograph), represent a new species of primitive duck-billed dinosaur.  The dinosaur has been named Eotrachodon orientalis (dawn rough tooth from the east).  It is the most complete primitive hadrosaurid dinosaur ever to be found in the eastern United States.

An Illustration and Scale Drawing of E. orientalis

The orange shaded area indicate fossils found.

The orange shaded area indicate fossils found.

Picture Credit: Florida State University with additional annotation by Everything Dinosaur

In Honour of Trachodon

Lead author of the scientific paper, published this week in the “Journal of Vertebrate  Palaeontology”, Albert Prieto-Marquez, stated that the genus name honours Trachodon, a name that would be very well known to fans of dinosaurs.  Trachodon is the genus erected in 1856 by Joseph Leidy as a result of fragmentary bones and teeth having been excavated from the Upper Cretaceous rocks (Judith River Formation) of Montana.  It was one of the very first American dinosaurs described, the first duck-billed dinosaur to be named (although some of the teeth used to describe it were later identified as Ceratopsian), and although the name is now regarded as a nomen dubium (not a valid genus), Trachodon appeared in countless books about dinosaurs for the best part of 120 years.  The popularity of Trachodon was helped by wonderful illustrations produced by palaeoartists such as Zdenek Burian (Trachodon and Tyrannosaurus rex).

Trachodon Became the Archetypal Duck-Billed Dinosaur

An illustration of Trachodon.

An illustration of Trachodon.

Picture Credit: Everything Dinosaur

Now Trachodon has been honoured with a valid genus (Eotrachodon).  At perhaps, nine metres long, Eotrachodon orientalis was certainly not the biggest, but the fossil find is extremely significant none-the-less.  Firstly dinosaur fossil finds are rare from the south-eastern United States.  To read an article about which U.S. States have dinosaur fossils: 37th U.S. State with A Dinosaur Fossil

Commenting on the significance of the discovery, one of the authors of the scientific paper, Gregory Erickson (Florida State University) explained:

“This is a really important animal in telling us how they came to be and how they spread all over the world.”

Did the Hadrosaurs Originate in Appalachia?

Whilst the specimen was being prepared at the McWane Science Centre (Birmingham, Alabama), the scientists were able to piece together the skull bones and identify a modified nasal area of the skull that had, until now been regarded as a characteristic associated with Saurolophine hadrosaurids (solid-crested and crestless forms).  Dating the fossil to the Late Santonian faunal stage (83 million years ago), it suggests that the duck-billed dinosaurs originated on the continental landmass known as Appalachia.  During the Late Cretaceous, North America was split by into two by a wide sea (the Western Interior Seaway), Laramidia lay to the west, whilst the larger landmass of Appalachia lay to the east.  Phylogenetic analysis indicates that Eotrachodon is a basal member of the hadrosaurids and thus, it can be postulated that this group of dinosaurs evolved on Appalachia.  Land bridges formed as the Western Interior Seaway permitted these dinosaurs to migrate off this continental landmass and to spread to other parts of the Late Cretaceous world.

Reseracher Jun Ebersole, (McWane Science Centre), stated:

“For roughly 100 million years, the dinosaurs were not able to cross this barrier.  The discovery of Eotrachodon suggests that duck-billed dinosaurs originated in Appalachia and dispersed to other parts of the world at some point after the seaway lowered, opening a land corridor to western North America.”

Fossil Find Suggests Hadrosaurids Originated from Appalachia

Sweet Home Alabama.

Sweet Home Alabama!

Picture Credit: Everything Dinosaur

A View of the Left Lateral Side of the Skull

Scale bar = 5cm

Scale bar = 5cm

Picture Credit: Albert Prieto-Marquez et al

Cambridge Plesiosaur Donated to Oxford Could Be New Species

Potential New Plesiosaur Species

A nearly complete plesiosaur skeleton that came to rest in marine sediments now located in northern Cambridgeshire might just prove to be a new species.  The fossilised remains were excavated out of a layer of rock discovered in a fenland quarry in November 2014, by archaeologists from the Oxford Clay Working Group.  A nearly complete plesiosaur skeleton that came to rest in marine sediments now located in northern Cambridgeshire might just prove to be a new species.  Over the next four days the team were able to excavate and remove nearly 600 bone fragments that represent a considerable portion of the entire skeleton.  Only some limb elements are missing.  The fossil, nick-named Eve, represents an individual around five and a half metres in length, early indications are that the bones show similarities with another plesiosaur known from the Peterborough area, called Picrocleidus.  However, Picrocleidus is believed to have been much smaller, at less than half the length of this new discovery, and its fossils are associated with much younger Jurassic strata (Callovian faunal stage), whilst “Eve” was found in rocks dating from about 165 million years ago (Bathonian faunal stage of the Jurassic).

The Huge Humerus (Upper Arm Bone) of the Plesiosaur

Sea monster from a Cambridge fen.

Sea monster from a Cambridge fen.

Picture Credit: Oxford University Museum of Natural History

Dr. Carl Harrington, a member of the Oxford Clay Working Group, was the first person to find bones of this new sea monster.  Describing the find as “fantastic”, Dr. Harrington recalled the moment he first uncovered the delicate skull bones:

It was one of those absolute “wow” moments.  I was the first human to come face-to-face with this reptile.”

The quarry is owned by building supplies company Forterra and this part of Cambridgeshire has become very well known for its Jurassic vertebrate fossil finds.  For example, the first fossils of the giant prehistoric fish Leedsichthys  (L. problematicus) were also found in the Peterborough area.  Forterra have donated the specimen to the Oxford University Museum of Natural History, where the fossilised remains are currently being prepared and studied in more detail with a view to determining whether or not this is a new species of marine reptile.

An Artist’s Interpretation of the New Marine Reptile (Plesiosaur)

Scale bar = 1 metre.

Scale bar = 1 metre.

Picture Credit: Nobomichi Tamura with additional annotation by Everything Dinosaur

Plesiosaurs had two pairs of  oar-like paddles which they used to propel themselves through the water, recent studies suggest that, just like extant penguins, these marine reptiles, some of whom could reach lengths in excess of fifteen metres, actually “flew” through the water.

To read more about this research into plesiosaur propulsion: Computer simulations and marine reptile underwater flight

Nice to see that Cambridge is prepared to donate a pair of oars to Oxford, their bitter rowing rivals.

The Field Team Exclaimed that they had Never Seen so Many Vertebrate Fossils in Such a Small Area

A very fossiliferous area indeed!

A very fossiliferous area indeed!

Picture Credit: Oxford Museum of Natural History

Quarry Site Might Reveal Evidence of Cretaceous Mass Extinction

Potential to Map End Cretaceous Extinction Event in New Jersey Quarry

The eastern part of the United States might be regarded as something of a “poor relation” to the western side of the country when it comes to dinosaur bones.  True, eastern USA dinosaur fossils are much rarer than from locations such as Wyoming, Utah, Arizona, Colorado and Montana in the west, but the State of New Jersey might just have one very special “Lagerstätte”, that tops those vertebrate fossil bearing rocks known elsewhere in America.  A disused quarry located close to the township of Mantua might provide palaeontologists with unique insights into the End Cretaceous mass extinction event that wiped out the non-avian dinosaurs.

New Jersey Quarry Might Provide Fresh Insight into Cretaceous Mass Extinction Event

Excavating invertebrate fossils in the quarry.

Excavating invertebrate fossils in the quarry.

Picture Credit: Rowan University

Around sixty-five million years ago, this site was at the bottom of a shallow sea, close to the landmass known as Appalachia.  In one layer of rock, about fourteen metres below the level of today’s land surface, scientists have found a treasure trove of marine fossils.  Professor Kenneth J. Lacovara, a professor of palaeontology and geology at the nearby Rowan University describes this particular bed as a “mass death assemblage”.  Could all these animals have perished as a result of a single catastrophic event, such as an extraterrestrial impact event?

If this is the case, then this quarry, which sits behind a shopping mall, could be the only site in the world where animal remains can be found that date from the End Cretaceous mass extinction event.  Fossils are found in a number of rock layers in the quarry, but a vast assemblage is confined and concentrated to one bed in the strata.  The rocks have been dated to around 65 million to 66 million years old, but further radiometric and biostratigraphic analysis is required before the link with the mass extinction event can be given more validity.  If a connection is established, then this location could provide an unparalleled window into a pivotal moment in the history of life on Earth.

Elevated amounts of the rare Earth element iridium found in close proximity to the richest fossil bearing layer, indicate that these animals lived at a time extremely close to what is believed to have been an asteroid impact, one that played a major role in the extinction of about 75% of all terrestrial species.

Last year, Rowan University entered into an agreement to purchase the sixty-five acre site.  The University intends to turn the quarry into a world-class educational resource.  A number of open days have already been organised and it has been estimated that some 8,000 local people have already taken part in fossil digs.

An Aerial View of the Mantua Quarry Site

A window into the End Cretaceous extinction event.

A window into the End Cretaceous extinction event.

Picture Credit: Rowan University

Fossils found include a vast array of marine invertebrates, animals like Brachiopods, Bivalves and Molluscs.  In addition, shark teeth are relatively common and fossils from ancient crocodiles and turtles have also been discovered.  Occasionally, the fossilised remains of a Mosasaur (marine reptile) are found.  Bones and other remains from once living organisms such as teeth and shells can pile up as underwater currents relocate them on the seabed, concentrating them into one area, perhaps where the current dies away.  However, at this location, one bed reveals skeletons of larger animals have remained relatively intact.  This suggests that these animals all died at approximately the same time and then settled gently on the sea bottom.  Initial dating assessments, puts this fossil layer tantalisingly close to the extraterrestrial impact event that took place in the Yucatan peninsula (Mexico).

Now that the future of this rather special site has been secured, scientists hope to undertake a much more extensive study of the palaeogeography of the area and to establish this location’s potentially unique relationship to the extinction event that wiped out the non-avian dinosaurs as well as the Pterosauria and most of the marine reptiles.

Wales Gets a New Dinosaur – Dracoraptor

The Dragon Thief of Wales – Dracoraptor hanigani

The beautifully preserved meat-eating dinosaur fossil found at Lavernock Point (south Wales) has been formally named and described.  Say hello to Dracoraptor hanigani, a two metre long predator whose fossilised remains were found by brothers Rob and Nick Hanigan.  Reporting in the open access on line journal “PLOS One”, the fossilised material very probably represents the oldest known Jurassic dinosaur found to date in the British Isles.

Dracoraptor hanigani – An Agile Little Hunter

On display the fossils with a skeleton reconstruction.

On display the fossils with a skeleton reconstruction.

Picture Credit: National Museum of Wales

To read more about this exciting fossil find: Welsh Dinosaurs – New Early Jurassic Theropod from South Wales

The genus name means “dragon thief”, in honour of one of the national symbols of Wales, the species name honours the two fossil-hunting brothers who found it.  This little hunter may only be distantly related to the “raptors”, but it does represent a significant fossil find, as dinosaurs are particularly rare in Lower Jurassic rocks.  Dracoraptor, lived on an island archipelago, some 201.3 million years ago, plus or minus 200,000 years, the preserved bones and teeth (some 40% of the skeleton), have been so precisely dated in geological terms thanks to biostratigraphic dating of the strata.  The rock layers can be divided up into distinct zones (biozones) based on the characteristic fossils that layer contains.  The dinosaur’s remains were found between two well-documented zonal layers.  It was found above a conodont* zone (Chirodella verecunda), associated with the very end of the Triassic and below an ammonite zone Psiloceras planorbis, which is associated with the first faunal stage (Hettangian) of the Jurassic.

*Conodonts are an extinct group of tiny, jawless, marine animals that had mouths filled with several pairs of tooth-bars.  They are believed to be related to early, jawless fish and probably superficially resembled eels.  Their distinctive teeth, often found in abundance, provide very useful “markers” in rocks, helping palaeontologists to date the relative ages of different rock layers.  Conodonts became extinct at the end of the Triassic.

Helping to Understand the Early Diversity of the Dinosauria

The fossil, collected from a cliff fall at Lavernock Point, has had a charmed life.  Firstly, the fossil was found in marine sediments, apparently, the carcase of this little dinosaur was washed out to sea and settled on the sea floor.  Sea urchins crawled over it and most likely fed on the rotting flesh, some of these sea urchins have been preserved in the surrounding rock matrix.  Currents did not disturb the bones, which explains why the specimen is so complete.  In addition, if Rob and Nick Hanigan had not chanced upon the specimen, the fossils would have been washed out to sea and lost forever in just a few days.

Furthermore, Everything Dinosaur reported on the serendipitous discovery of more of the specimen, by third year palaeontology student Sam Davies, who coincidently is tutored by one of the authors of the PLOS One paper, Dr. David Martill (School of Earth and Environmental Sciences, University of Portsmouth).

To read more about Sam’s lucky find: Lucky Find Puts Welsh Dinosaur on a Firm Footing

Views of One of the Teeth Associated with the Specimen (Presumed to be from the Upper Jaw)

This dinosaur probably ate insects and other small animals.

This dinosaur probably ate insects and other small animals.

Picture Credit: PLOS One

Explaining the significance of this fossil discovery, co-author of the paper Steven Vidovic (PhD Researcher at Portsmouth University), commented:

“It’s right at that point in the diversification of dinosaurs where so-called Theropod dinosaurs,  the meat-eating ones, became what are called Neotheropods.  It’s from this moment onwards that they go on to become all the forms we know, like T. rex, Velociraptor and even birds.”

Very Rare Fossil Find

Early Jurassic dinosaur fossils are extremely rare and this particular specimen, which may represent an immature adult, is very important as it provides data on the evolution of meat-eating dinosaurs so soon after the Triassic/Jurassic extinction event.  Dracoraptor hanigani is the first dinosaur to be described from the Jurassic of Wales.  It probably lived on a small island (part of St David’s Archipelago), or perhaps its corpse had been washed out sea from the nearby, larger land mass known as the Welsh Massif.  It is one of very few early Theropod remains found in Europe.

The Palaeogeography of the Early Jurassic (Europe – Hettangian)

Europe consisted of a series of islands 200 million years ago.

Europe consisted of a series of islands 200 million years ago.

Picture Credit: PLOS One

The picture above show the palaeogeography of western Europe, approximately 200 million years ago.  Modern western Europe has been superimposed to provide a reference.  The numbers in the small, yellow circles record the location of other early Theropod or Neotheropod discoveries:

  1. Isle of Skye
  2. Barrow upon Soar (Leicestershire)
  3. Wilmcote (Warwickshire)
  4. Lavernock Point – the location of the Dracoraptor find
  5. Dorset
  6. Airel (France)
  7. Brouch (Luxembourg)

A cladistic analysis suggests that Dracoraptor was a basal Neotheropod and it may have been related to Tawa hallae and Daemonosaurus chauliodus ( both from the Ghost Ranch location, New Mexico, United States).  Everything Dinosaur has written about the discovery of both Tawa and Daemonosaurus, for further information on these fast-running little predators, see the links below.

To read more about Tawa: New Theropoda Dinosaur Discovery Sheds Light on Dinosaur Diversification

To read more about Daemonosaurus: Little Demon from the Dawn of the Dinosaurs

Canada has its First Dimetrodon

Canada’s First Dimetrodon

A fossil found by a farmer digging a well on Prince Edward Island over 160 years ago has been finally identified by a student whilst studying for a PhD at the University of Toronto Mississauga.  The fossil, which consists of elements of the snout and upper jaw was once thought to have come from a meat-eating dinosaur, but a new analysis reveals that fearsome Dimetrodons once roamed Canada.  This is the first evidence that these giant, sail-backed reptiles from the Permian lived on the landmass that was to eventually form Canada.

Evidence of Dimetrodon in Canada

The curved teeth in the upper jaw can be clearly made out.

The curved teeth in the upper jaw can be clearly made out.

Picture Credit: (Carleton University/University of Toronto Mississauga)

The location of the fossil find remains a mystery, there may be more elements of this individual preserved, but the farmer did not provide a map of the location and what notes that have been attributed to this specimen make no mention of the actual spot where the discovery was made.  All we know is that the well was being dug near the French River (Prince Edward Island).  The specimen was acquired by the Academy of Natural Sciences (Philadelphia, USA) and Joseph Leidy, one of the world’s most eminent palaeontologists, studied it and named it Bathygnathus borealis.  Leidy thought that the fossilised bones and teeth (fragments of the premaxilla, a partial maxilla and elements of the naris along with several teeth), resembled those of Theropod dinosaurs that had been found in England.  Professor Leidy had incorrectly identified this fossil material as a dinosaur, making it the first dinosaur known from Canada.

A review of the fossil in 1905, identified it as a probable mammal-like reptile, however, it was a paper published in the academic journal “The Canadian Journal of Earth Sciences”, late last year that finally cleared up the mystery identifying the animal as a member of the Dimetrodon genera.

Lead author of the paper, Kirstin Brink who worked on the fossil whilst at the University of Toronto Mississauga, and a specialist in examining the teeth of prehistoric animals, explained:

“It’s really exciting to discover that the detailed anatomy of the teeth has finally allowed us to identify precisely this important Canadian fossil.”

An Illustration of the Canadian Dimetrodon

An illustration of Dimetrodon borealis, the insert shows the location of the fossil on the animal.

An illustration of Dimetrodon borealis, the insert shows the location of the fossil on the animal.

Picture Credit: Danielle Dufault

Dimetrodon – A New Species

Dimetrodon is perhaps one of the most famous of all the animals known from the Palaeozoic Era.  Several species of these sail-backed reptiles are known and their fossils have been found in the United States, Europe and now Canada.  The largest species, animals like D. grandis were the apex predators of terrestrial environments during the Late Permian, with some animals growing to around 3.5 metres in length.  Although not a dinosaur, Dimetrodon seems to have become forever linked with the Dinosauria.  For example, Dimetrodon models are often included in dinosaur model sets.

A Dimetrodon Model

Sail-back reptile with ferocious teeth.

Sail-back reptile with ferocious teeth.

Picture Credit: Everything Dinosaur

Kirstin has specialised in studying the preserved teeth of prehistoric animals.  Using parsimonious relationship analysis (family trees) and high resolution imaging, the researchers were able to link the teeth to the Dimetrodon genus.  The teeth are “ziphodont”, that is, they are serrated along the cutting edge.  Dimetrodon is thought to be the first terrestrial vertebrate to possess such teeth.

Professor Robert Reisz (University of Toronto Mississauga), one of the author’s of the research paper published last year stated:

“These are blade-like teeth with tiny serrations along the front and back of the teeth, similar to a steak knife.  The roots of these teeth are very long, around double the length of the crowns.  This type of tooth is very effective for biting and ripping flesh from prey.”

What’s in a Name?

Long tooth roots and these ziphodont serrations are diagnostic of Dimetrodon, ironically, the renaming of this animal from Bathygnathus borealis to Dimetrodon borealis might spell trouble for all fans of this sail-backed reptile.  As Bathygnathus was named before the Dimetrodon genus was erected, then technically, under the strict guidelines of the International Code of Zoological Nomenclature (ICZN) the name given first should take precedence.

In essence, all fossil material related to the Dimetrodon genus should be renamed as Bathygnathus (the name means “deep jaw from the north”).

Dr. Brink, now based at the University of British Columbia expressed her concern:

“What we’re hoping will happen is the priority will be reversed so we can keep Dimetrodon as a valid name, just because it’s so well known among the public and other scientists as well.”

Although the fossil material has not turned out to be a dinosaur, the naming of a new species of Dimetrodon, one that lived further north than any other species of Dimetrodon so far described, still makes this specimen a very remarkable fossil indeed.

“Siva’s Beast” Goes on a Diet

Sivatherium giganteum – Not Quite So Giganteum!

A re-assessment of an ancient prehistoric mammal that once roamed the foothills of the Himalayas, has led to the palaeontological shrink ray being employed once again.  The beast, an ancient giraffid named Sivatherium giganteum (pronounced See-vah-fear-ree-um jai-gant-tee-um) was once thought to be some form of missing link between elephants and giraffes, 19th Century scientists thought that it was about as big as an African elephant.  However, a digital reconstruction and re-examination of the fossilised bones of these herbivores has led to a new body mass estimate of around 1,250 kilogrammes (a range of 857 kg to 1,812 kg).

Sivatherium giganteum – Once Thought to be a Missing Link Between Elephants and Giraffes

Fossils found in Africa and Asia.

Fossils found in Africa and Asia.

Picture Credit: Science Photo Library

The first fossil specimen to be scientifically studied was found by Scottish geologist Hugh Falconer who accompanied the English engineer Proby Thomas Cautley on an expedition to map the terrain of the Sivalik Hills in the sub-Himalayas region of India.  A scientific paper naming and describing this animal was published in a journal called the “Philosophical Magazine Series” back in 1836.  Despite further fossil finds and the naming of a number of Sivatherium species (India and Africa), until now there had been no attempt at a complete skeletal reconstruction of the creature.

The bones that make up the skeleton were digitally mapped and then the animal was reconstructed.  The researchers, which included scientists from the Royal Veterinary College, were able to calculate a range of body masses for this impressive beast, although this new research (published in Biology Letters), suggests that the 19th Century study did over estimate the body mass by a considerable margin.

Commenting on the work of his predecessors, Christopher Basu (co-author of the new study) stated that the 19th Century team did a “beautiful job at describing it and taking measurements, although it turns out the body mass calculation was educated guesswork.”

As part of a wider investigation into the anatomy of modern giraffes, the three-dimensional computer model of S. giganteum provides a much more accurate estimate of body mass.  “Sivas Beast” had particularly robust bones and the body mass estimate provided by the earlier research was based on a volumetric measure.  However, assessment of the weight bearing capacity of the humerus (humeral circumference) and other measurements in this new study provides a more accurate reading.

Although, not quite on the scale of a modern African elephant, Sivatherium giganteum is one of the largest ruminants known to science.  Males may well have been slightly heavier than the average body weight given in this new research, they had very large horns and these spectacular appendages would have increased their overall body mass.

Skeletal Reconstruction of Sivatherium giganteum

scale bar = 1 metre.

scale bar = 1 metre.

Picture Credit: Royal Veterinary College/Biology Letters

In the picture above the skeletal reconstruction in green (top) shows Sivatherium modelled against modern Giraffa.  The outline in purple and the bones (also in purple) provide an outline of the minimum body proportions modelled onto the skeletal frame.

Commenting on the study, carried out in association with Liverpool John Moores University, PhD student Christopher Basu explained:

“As a palaeontologist, it is really important to understand the basic question – how big was this animal?  This was probably the largest giraffe relative to have ever existed, which makes it the largest ruminant that’s ever existed.  It’s a rare animal, it’s pushing the limits of its anatomy.”

With its short neck and robust body, S. giganteum may not look much like a modern giraffe, but surprisingly, this animal co-existed with modern giraffes in Africa.  Fossil evidence suggests that Sivatherium may have survived into the Holocene Epoch.  In addition, archaeologists have discovered a series of rock drawings dating from between 10,000 and 8,000 years ago at various locations in the Sahara region of North Africa that depict animals that resemble Sivatherium.  Although, it is difficult to say beyond doubt that these images resemble Sivatherium it is an intriguing and interesting thought.

The Reconstructed Skeleton of Sivatherium giganteum

Biggest ruminant known to science.

Biggest ruminant known to science.

Picture Credit: Royal Veterinary College/Biology Letters

To read an article about an ancient ruminant and its links to a Star Wars character: Xenokeryx and Giraffes – Something To Ruminate On

“Attenborough and the Giant Dinosaur”!

BBC Announces Date for TV Programme About “World’s Biggest Dinosaur”

Exciting news for dinosaur fans of all ages.  The BBC has ended the embargo on a new documentary programme outlining the discovery and study of over two hundred giant dinosaur bones found in Argentina.  The fossils represent a new species of enormous long-necked dinosaur (Titanosaur) and when finally named and scientifically described, this could be the largest dinosaur known to science, surpassing the likes of Argentinosaurus (A. huinculensis) and Futalognkosaurus dukei, fossils of which also come from Argentina.

Sir David Attenborough Lies Alongside a Giant Femur (Thigh Bone)

Potentially the biggest terrestrial animal known to science.

Potentially the biggest terrestrial animal known to science.

Picture Credit: BBC

The picture above provides a sense of scale for the huge animal, Sir David Attenborough is lying next to right femur (thigh bone) which measures 2.4 metres long.  This is the largest thigh bone ever found from a terrestrial animal.  Femora circumference data suggests a body mass in excess of seventy tonnes.

To read Everything Dinosaur’s report on the discovery of the fossil bones: The Biggest Dinosaur of All! A New South American Contender

A Graveyard of Giants

The television programme will be shown on BBC1 at 6.30pm on Sunday, 24th January.  It tells the story of how the fossils (over 220 of them have been excavated and catalogued), were found and follows the scientific research from excavation, preparation and cleaning right up to the unveiling of a life-sized model of the new type of Titanosaur.  With such a large number of bones to examine, the scientists have been able to build up quite a detailed picture of this dinosaur.  The fossilised bones represent a total of seven individual dinosaurs, the largest of which was the one that the Canadian and Argentinian team of model makers based their reconstruction on.

To conclude the programme, Sir David will unveil the new reconstruction of this enormous herbivore.  The model measures 37 metres long, that’s almost the equivalent of tacking the playing surface of Wimbledon’s Centre Court onto the length of a basketball court.  For comparison, “Dippy” the Diplodocus replica housed at the Natural History Museum (London), is only 26 metres long.  The reconstruction of Argentinosaurus huinculensis, housed in the Museo Municipal Carmen Funes, Plaza Huincul (Neuquén Province, Argentina) is around 35 metres in length.

The Reconstruction of A. huinculensis (Museo Municipal Carmen Funes)

The largest dinosaur yet described.

The largest dinosaur yet described, but under threat.

Picture Credit: Museo Municipal Carmen Funes, Plaza Huincul

Recalling the problems associated with the excavation of such huge fossils, Dr Diego Pol, lead scientist heading up the research team based at the Museum of Palaeontology Egidio Feruglio, (Trelew, Argentina) stated:

“It was like a palaeontological crime scene, a unique thing that you don’t find anywhere else in the world with the potential of discovering all kinds of new facts about Titanosaurs.  According to our estimates this animal weighed 70 tonnes.  A comparison of the back bones shows that this animal was ten per cent larger than Argentinosaurus, the previous record holder.  So we have discovered the largest dinosaur ever known.”

The date when this animal roamed differs in the press release from that stated earlier when Everything Dinosaur first published details of the fossil discovery.  The BBC press release suggests that this giant dinosaur roamed around 101 million years ago, whilst our data suggests that it lived slightly later, around 95 million years ago (Cenomanian faunal stage of the Cretaceous).

The heart of this huge beast would have weighed something like 200 kilogrammes and with a circumference estimated at two metres it would have pumped ninety litres of blood round the body with one huge beat.  That’s more liquid than the average amount of water that people have a bath in.

“Attenborough and the Giant Dinosaur” will broadcast on BBC1 on Sunday 24 January at 6.30pm.  It will be available on the BBC catch up services and we at Everything Dinosaur are eagerly looking forward to watching the programme.

Sir David Attenborough and the Giant Dinosaur Thigh Bone

That is a very big thigh bone!

That is a very big thigh bone!

Picture Credit: BBC

Not the End of the Story

A formal scientific paper will be published shortly and this new dinosaur will be given a scientific name, it is likely to be a record breaker and regarded as the largest land living animal known to science.  However, readers of this blog know that Everything Dinosaur takes a keen interest in such matters, check out the link below that hints at the presence of even larger dinosaurs within the fossil record:

 One hundred tonne Titanosaurs?: Giant Fossil Titanosaur Tooth Hints at “Enormosaurus”

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