Everything Dinosaur is offering to give away three very special signed copies of “Dinosaurs – how they lived and evolved” by Darren Naish and Paul M. Barrett, a fantastic book published by the Natural History Museum of London in our free to enter competition.
PLEASE NOTE THIS COMPETITION IS NOW CLOSED
Win a Fantastic Dinosaur Book with Everything Dinosaur
Suggest a name for Tianyulong on the front cover to enter Everything Dinosaur’s competition. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
An Amazing Dinosaur Book
We have three of these marvellous books to give away and each one contains a unique, signed drawing by Darren Naish.
Each Book Contains a Unique, Signed Drawing by Darren Naish
Each book in the Everything Dinosaur competition contains a unique signed drawing. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
“Like” the Everything Dinosaur Facebook Page
All you have to do is “Like” Everything Dinosaur’s FACEBOOK page, then comment on the “Dinosaurs – how they lived and evolved” picture, providing a suggested name for the Tianyulong dinosaur featured on the front cover.
We will draw the lucky winners at random and the “Dinosaurs – how they lived and evolved” competition closes on midnight Sunday 14th June. Good luck, we hope you win one of these unique dinosaur books.
Terms and Conditions of the “Everything Dinosaur Dinosaurs – how they lived and evolved” Book 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 Dinosaurs – how they lived and evolved” competition runs until midnight Sunday 14th June 2020.
Winner will be notified by private message on Facebook.
Prize includes postage and packing.
This giveaway is in no way sponsored, endorsed, administered by or associated with Facebook.
Everything Dinosaur acknowledges a complete release of Facebook by each entrant/participant.
Beautiful Photographs of Fossils and Detailed Text
Lots of amazing photographs of dinosaur fossils and detailed, informative text in this new dinosaur book entitled “Dinosaurs – how they lived and evolved” by Darren Naish and Paul M. Barrett. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
To enter Everything Dinosaur’s book competition, all you have to do is “Like” Everything Dinosaur’s FACEBOOK page, then comment on the “Dinosaurs – how they lived and evolved” picture, providing a suggested name for the Tianyulong dinosaur featured on the front cover.
The illustration of the bizarre Jurassic heterodontosaurid Tianyulong confuciusi that features on the front cover was created by the very talented palaeoartist Bob Nicholls.
Dinosaur-dooming Bolide Struck Earth at Worst Possible Angle
The extra-terrestrial object, whether it was a comet or an asteroid, that devastated our planet some sixty-six million years ago, struck Earth at the “deadliest possible” angle according to new research published this week in the journal Nature Communications. Computer simulations created by researchers based at Imperial College London indicate that the huge object struck Earth at an angle of 45 to 60 degrees to the horizontal. This maximised the amount of climate-changing gases that were thrust into the upper atmosphere.
A Sinkhole Near the Chicxulub Crater in Mexico
Plant diversity at a cenote (sinkhole) near the Chicxulub crater caused by the bolide hit 66 Million years ago. Picture credit: Jamie Thompson.
Picture credit: Jamie Thompson
The Significance of the Impact Trajectory
The severity of an extra-terrestrial impact is influenced by a number of factors. For example, the size and the mass of the bolide, the speed of the impact and the trajectory and direction of impact. The impact direction and the angle of the collision affect the amount of ejector that is thrown up into the atmosphere. For the non-avian dinosaurs, it was a question of a number of factors that exacerbated the mass extinction event. Although there has been a considerable amount of research carried out on Chicxulub crater the impact trajectory remains controversial.
The use of three-dimensional computer simulations along with geophysical observations suggests that the crater was formed by a steeply-inclined impact from the northeast. Such a strike likely unleashed billions of tonnes of sulphur. The sulphur would have reacted with the oxygen and other elements to form acid rain which would then have fallen to Earth and further devastated the environment. The debris in the atmosphere would have blocked out the sun and triggered a nuclear winter effect. This catastrophe led to the extinction of 75% of life on Earth.
The simulations were performed on the Science and Technology Facilities Council (STFC) DiRAC High Performance Computing Facility.
Plotting a Momentous Few Minutes in the History of Planet Earth
The team used computer simulations and geophysical data to recreate the Chicxulub impact event. The computer simulations permitted the researchers to map the entire crater formation event in unprecedented detail.
Picture credit: Imperial College London/Nature Communications
Lead author of the scientific paper, Professor Gareth Collins of the College’s Department of Earth Science and Engineering stated:
“For the dinosaurs, the worst-case scenario is exactly what happened. The asteroid strike unleashed an incredible amount of climate-changing gases into the atmosphere, triggering a chain of events that led to the extinction of the dinosaurs. This was likely worsened by the fact that it struck at one of the deadliest possible angles.”
The Crater Creation
The top layers of rock around the Chicxulub crater in the Yucatan peninsula contain high amounts of water as well as porous carbonate and evaporite material. When disturbed and greatly heated by the energy of the impact, these rocks would have been vaporised flinging huge amounts of the greenhouse gas carbon dioxide, sulphur and water vapour into the atmosphere. The sulphur and other particles would have formed aerosols as well as acidifying the atmosphere. These aerosols would have blocked out sunlight stopping photosynthesis and leading to the collapse of food chains. The world would have been plunged into a nuclear winter.
A Geophysical Map of the Impact Crater
A geophysical gravity map showing the outline of the Chicxulub crater and its surrounding environment.
Picture credit: Imperial College London/Nature Communications
Studying the Dinosaur Extinction
Working in collaboration with colleagues from the University of Freiburg (Germany) and the University of Texas at Austin the impact event was re-created in extensive detail, which will help scientists to better understand impact craters on our own planet as well as those found elsewhere within the solar system. Crucial to determining the angle and direction of the impact was the relationship between the centre of the crater, the centre of the peak ring (a circle of mountains made of heavily fractured rock inside the crater rim) and the centre of dense, uplifted mantle rocks.
Co-author of the scientific paper, Dr Auriol Rae (University of Freiburg) added:
“Despite being buried beneath nearly a kilometre of sedimentary rocks, it is remarkable that geophysical data reveals so much about the crater structure, enough to describe the direction and angle of the impact.”
Everything Dinosaur acknowledges the help and assistance of a media release from Imperial College London in the compilation of this article.
The scientific paper: “A steeply-inclined trajectory for the Chicxulub impact” by G. S. Collins, N. Patel, T. M. Davison, A. S. P. Rae, J. V. Morgan, S. P. S. Gulick, IODP-ICDP Expedition 364 Science Party and Third-Party Scientists published in Nature Communications.
Jawbone Leads to an Isle of Wight Tapejarid Pterosaur
A single, fragmentary jawbone from the upper jaw of a pterosaur found on the Isle of Wight has demonstrated just how diverse and widespread the Tapejaridae family of pterosaurs were. The fossil bone, a partial premaxilla from the Lower Cretaceous (Barremian) Wessex Formation of Yaverland (Isle of Wight), represents a new species, the first record of a tapejarid pterosaur from the Wessex Formation and one of the oldest examples of this pterosaur family to have been found outside of China. The flying reptile has been named Wightia declivirostris.
Wightia declivirostris
A Life Reconstruction of Wightia declivirostris (Wessex Formation)
A life reconstruction of the newly described tapejarid from the Lower Cretaceous of the Isle of Wight (Wightia declivirostris).
Picture credit: Megan Jacobs (University of Portsmouth)
Terrific Toothless Tapejarids
The terrific toothless tapejarids with their reputation for taking head crest development to the extreme, are known from relatively abundant fossil material associated with the Santana and Crato Formations of Brazil. In addition, several members of the Tapejaridae family are associated with the Jiufotang Formation of China. However, fragmentary fossils are known from elsewhere in the world such as Spain (Europejara olcadesorum) and a toothless, rather deep lower jaw tip along with other partial bones from the Kem Kem beds of Morocco suggests that these types of flying reptile may have persisted into the early Late Cretaceous.
Two of the authors associated with this scientific paper, Professor David Martill and Roy Smith (both from the University of Portsmouth), recently published a report on the discovery of a north African tapejarid which was named Afrotapejara zouhrii, one of a spate of recent Moroccan pterosaur discoveries. To read Everything Dinosaur’s article about this: That Fourth Moroccan Pterosaur. It seems that these fancy-crested, edentulous flying reptiles were much more geographically and temporally diverse than previously thought.
A Typical Illustration of a Tapejarid Pterosaur (Tupandactylus imperator)
A scale drawing of the tapejarid Pterosaur Tupandactylus imperator. The Tapejaridae are thought to have all sported flamboyant head crests.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
The Isle of Wight Pterosaur is More Closely Related to Chinese Tapejarids
Amateur fossil hunter John Winch discovered a pterosaur snout near the cliff at Yaverland Point in Sandown Bay, in a fossil plant debris layer. The unusual shape and thin bone walls suggested that it was from a pterosaur. The fragment of jaw, although eroded, demonstrates the characteristic downturned tip, with numerous tiny holes (foramina), on the occulsal surface which indicate the presence of minute sensory organs for detecting food.
The Holotype Material Wightia declivirostris
The isolated, partial premaxilla of Wightia declivirostris.
Picture credit: University of Portsmouth
The jaw fragment was passed to palaeontology student at Portsmouth University, Megan Jacobs, who confirmed it was a rare find and definitely pterosaurian. Analysis of the specimen suggests that Wightia is more closely related to the older and more primitive tapejarid Sinopterus from Liaoning (Jiufotang Formation), than it is to Brazilian tapejarids. The genus name of this newly described flying reptile honours the Isle of Wight, whilst the species (trivial) name means “slanting beak”, a reference to the typically tapejarid morphology of the partial premaxilla.
Both the Wealden Formation and the geologically younger Vectis Formation on the Isle of Wight have yielded pterosaur specimens, although they tend to consist of highly fragmentary remains. The discovery of Wightia declivirostris demonstrates how significant the Lower Cretaceous Isle of Wight sediments are to palaeontologists as they try to plot the radiation of different types of flying reptile during the Early Cretaceous.
The scientific paper: “First tapejarid pterosaur from the Wessex Formation (Wealden Group: Lower Cretaceous, Barremian) of the United Kingdom” by David M. Martill, Mick Green, Roy E. Smith, Megan L. Jacobs and John Winch published in the journal Cretaceous Research.
The eagerly awaited Rebor alien/Tyrannosaurus rex hybrid figure is coming into stock at Everything Dinosaur around late July to early August. This figure, the second in a planned series of four models entitled Swarm X-REX plague, is currently in production and it should be ready to ship at the end of June for a delivery into Everything Dinosaur’s warehouse a few weeks’ later.
The Rebor Alien – T. rex Hybrid Swarm X-REX in the Plague Colouration
The Rebor Swarm X-REX alien/T. rex hybrid model (plague colour variant).
A 1/35th Scale Rebor Model
Model collectors and fans of science fiction have a new range of Rebor figures and replicas to admire. “Plague” is the second model to be introduced in this line of 1:35 scale replicas representing an alien xenomorph/dinosaur crossover. We expect this new figure to be the same size as the first model in this range “Broodlord”, so the Swarm X-REX plague colour variant will measure around 43 centimetres in length.
The Frightening X-REX “Plague” on the Prowl
The Rebor Swarm X-REX alien/T. rex hybrid model (plague colour variant). An amazingly detailed xenomorph/dinosaur replica in 1:35 scale.
Rebor planned to introduce four brand new, innovative science-fiction/Dinosauria inspired figures this year, the first, “Broodlord”, the X-REX metallic variant, came out in February, now collectors will be able to match “Broodlord” with “Plague” when “Plague” comes into stock in the summer.
A Closer Look at the Amazing Detail on the Head, Neck and Shoulders of the X-REX Figure
The Rebor Swarm X-REX alien/T. rex hybrid model (plague colour variant). A close look at the amazing detail on the replica.
Due into Stock Very Soon
For fans who missed out on “Broodlord” a small stock of these figures is due to arrive at the Everything Dinosaur warehouse in a few weeks’ time. A spokesperson from Everything Dinosaur commented:
“We are bringing some more of the X-REX metallic colour variant into stock, these figures should be with us around the middle of June. This figure could of course, arrive a few days earlier. We anticipate that the second model in this series – plague, it could be in stock late July or early August – if all goes to plan.”
A View (Lateral View) of the Rebor Swarm X-REX Plague Variant
The Rebor Swarm X-REX alien/T. rex hybrid model (plague colour variant). The model is believed to approximately the same size of the previously released “Broodlord” and it is expected to measure around 43 cm in length.
Everything Dinosaur has opened a priority reserve list for the Swarm X-REX plague colour variant, to request a model be reserved: Email Everything Dinosaur.
Wild Safari Prehistoric World Ichthyosaurus “Turntable Tuesday”
In this week’s “Turntable Tuesday” video, it was the turn of the recently introduced Wild Safari Prehistoric World Ichthyosaurus model to go for a spin. This figure is one of nine new for 2020 prehistoric animal replicas from Safari Ltd, it was the only marine reptile amongst the company’s new releases, but what a splendid model it is. In our short video, we provide fans of prehistoric animal models with a three-hundred and sixty degree view of this replica.
“Turntable Tuesday” It’s the Turn of Ichthyosaurus
Video credit: Everything Dinosaur
Wild Safari Prehistoric World Ichthyosaurus Model
The Wild Safari Prehistoric World Ichthyosaurus sports a colouration that resembles the Killer Whale (Orcinus orca). Several species of Ichthyosaurus are now recognised, this taxon having been something of a taxonomic waste basket for much of the 19th and 20th centuries. Ichthyosaurus was much smaller than an extant Killer Whale, with the largest individuals less than 3.5 metres long and some species such as Ichthyosaurus communis, which was the named and scientifically described in 1822, being smaller still, with most specimens from the Dorset coast for example, averaging 2 metres in length.
The Wild Safari Prehistoric World Ichthyosaurus Model
The Ichthyosaurus model (Wild Safari Prehistoric World) ready to take its turn on the Everything Dinosaur turntable.Picture credit: Everything Dinosaur.
The 2020 Ichthyosaurus replaces the 2010 Ichthyosaurus from Safari Ltd. In the “Turntable Tuesday” video the beautiful detailing around the eyes is highlighted along with the model’s colouration. A segment of the video is dedicated to showing the underside of the figure. The cloaca (vent) is highlighted, demonstrating how the sculptors at Safari Ltd have gone to great lengths to ensure an accurate interpretation of a marine reptile.
The Video Shows the Underside and Highlights the Presence of a Cloaca on the Ichthyosaur Model
The Wild Safari Prehistoric World Ichthyosaurus model. The red arrow highlights the location of the cloaca (vent).Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Wild Safari Prehistoric World Ichthyosaurus Replica
Comparing the 2010 Ichthyosaurus model with the 2020 Ichthyosaurus. The 2010 Ichthyosaurus figure was depicted holding an ammonite in its jaws. Palaeontologists believe that the principle constituents of the diet of Ichthyosaurus were small fish and squid.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Measuring around nineteen centimetres in length, the new for 2020 Ichthyosaurus replica makes a fine addition to a prehistoric animal model collection.
A Close View of the Head of the Wild Safari Prehistoric World Ichthyosaurus Replica
A close-up view of the head of the Wild Safari Prehistoric World Ichthyosaurus model.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
The “Turntable Tuesday” video showcasing the remarkable Ichthyosaurus model can be found on Everything Dinosaur’s YouTube channel: Everything Dinosaur on YouTube.
We recommend that you subscribe to Everything Dinosaur on YouTube.
Two new PNSO dinosaur models are coming into stock at Everything Dinosaur! Aaron the baby Tyrannosaurus rex figure along with A-Qi the young Sinoceratops will be in stock at Everything Dinosaur in just a few weeks. These two beautiful figures are just the latest in a long line of exciting prehistoric animal replicas to be produced by PNSO.
PNSO Dinosaur Models
Aaron the Baby Tyrannosaurus rex Coming to Everything Dinosaur
Aaron the baby Tyrannosaurus rex dinosaur model (PNSO).
A-Qi the Young Sinoceratops Dinosaur Model
A-Qi the baby Sinoceratops model (PNSO).
A spokesperson for the UK-based company stated:
“Everything Dinosaur team members are really looking forward to the arrival of these two very cute and beautifully sculpted dinosaur figures. Both models have been carefully created based on ontogenic studies of baby dinosaurs and Aaron the young T. rex figure will sport a coat of “dino fuzz”, that would not only have served to keep this baby dinosaur warm, but also offered it some camouflage, just in case a dromaeosaurid or some other predator decided that baby dinosaurs were on the menu.”
Lots of PNSO Figures Coming into Stock at Everything Dinosaur
As well as these two new exciting replicas, the shipment will contain a lot of other PNSO prehistoric animal replicas, helping to replenish Everything Dinosaur’s stock of Patton the Megalodon, Duke the Spinops, Paulwin the Dakosaurus, Essien the Spinosaurus, Nick the Ceratosaurus and Lucas the Giganotosaurus. In total, seventeen different product lines will be re-stocked.
Lots of PNSO Figures Coming to Everything Dinosaur
Lots of PNSO figures and replicas coming back into stock at Everything Dinosaur.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
The PNSO prehistoric animals are due to be shipped from the factory this week (end May 2020). If all goes to plan, these exciting prehistoric animal figures and replicas including Aaron the young Tyrannosaurus rex and A-Qi the cute, baby Sinoceratops will be in stock on-line at the company’s website in July.
The Young Sinoceratops Coming into Stock at Everything Dinosaur
A-Qi the baby Sinoceratops model (PNSO).
Aaron the Young T. rex Complete with a Coat of “Dino Fuzz”
Aaron the baby Tyrannosaurus rex dinosaur model (PNSO). Both PNSO baby dinosaur replicas exhibit characteristics associated with young animals, such as the proportionately large eyes and in the case of Aaron the T. rex, large feet, indicative of distal growth.
If you want to enquire about the two new PNSO baby dinosaurs, ask about reserving a figure or to request further information on any of the PNSO prehistoric animals, simply: Email Everything Dinosaur.
Nanotyrannus lancensis Fossils and the Link to Edmontosaurus annectens
Recently, Everything Dinosaur posted up an article featuring the research work undertaken on an extensive Edmontosaurus (E. annectens) bonebed located at Hanson Ranch in eastern Wyoming. The dinosaur fossils associated with the five quarries and three exploratory quarries are almost entirely representative of Edmontosaurus annectens. Approximately, 94 percent of all the dinosaur bones found at this site represent this Edmontosaurus species.
While the quarry is clearly dominated by the remains of Hadrosauridae, the researchers report finding a few skeletal elements assigned to bird-hipped dinosaurs such as ceratopsids, pachycephalosaurs, armoured dinosaurs (nodosaurids) and small ornithopods associated with the Thescelosauridae family. Such a large number of Edmontosaurus carcasses did not go unnoticed by carnivorous theropods. Shed teeth from meat-eating dinosaurs are common in the bonebed, evidence of these animals scavenging the decaying Edmontosaurus remains. The most common teeth associated with Hanson Ranch have been ascribed to the Dromaeosauridae and Troodontidae with the larger teeth identified as Tyrannosauridae.
The Fossil Bones of Nanotyrannus lancensis
Nanotyrannus (N. lancensis), is a controversial genus of tyrannosaurid dinosaur known from several fossil specimens including a remarkable fossil found in association with a ceratopsid nick-named “Bloody Mary”. The validity of this taxon is debated. Many palaeontologists claim that fossils ascribed to Nanotyrannus (dwarf tyrant), represent the remains of juvenile, sub-adult Tyrannosaurus rex.
In the scientific paper, detailing the Edmontosaurus bonebed, reference is made to a Nanotyrannus fossil discovery. In 2001, the remains of the foot of a Nanotyrannus lancensis were found on the surface at a nearby site designated Stair Quarry (not included in the Edmontosaurus study). The paper cites that over the next fifteen years or so, fifty additional bones from this specimen including a right maxilla with teeth in situ and a left dentary, also with some teeth present were discovered.
A PNSO Model of the Controversial Genus Nanotyrannus
The PNSO Nanotyrannus dinosaur model.
The picture (above) shows the PNSO Nanotyrannus dinosaur model.
In the scientific paper, the researchers comment that although these fossil remains have yet to be formally scientifically described, they have enabled the research team to clearly distinguish the slender, blade-like shed teeth of Nanotyrannus from the more robust, D-shaped crushing teeth of Tyrannosaurus, both of which are commonly found in the bonebed. It is intriguing to speculate that if this material ascribed to Nanotyrannus is studied extensively, then it might prove helpful in resolving the debate over the validity of the Nanotyrannus genus.
A Comprehensive Guide to the Fossils from the Kem Kem Beds of Eastern Morocco
A team of international researchers have documented the fossil vertebrates associated with the early Late Cretaceous (Cenomanian-Turonian) of the famous Kem Kem beds of eastern Morocco. They conclude that with the abundance of hypercarnivores such as Spinosaurus, abelisaurids, Carcharodontosaurus and Deltadromeus, several large pterosaurs and a multitude of giant fish and crocodyliforms, no comparable modern terrestrial ecosystem exists with a similar bias toward large-bodied carnivores.
Arguably, the sediments that make up the Kem Kem Group, which is composed of the lower Gara Sbaa and upper Douira formations, represent the most dangerous place and time in the whole of the Cretaceous.
Examples of Theropod Teeth Associated with the Kem Kem Group of Eastern Morocco
Indeterminate theropod teeth from the Kem Kem Group with (H) showing the denticles of (F) and (N) close up view of denticles in (M). Scale bar equals 2 cm in A-C and I-M whilst 3 cm in D and 5 mm in H and N.
Picture credit: Ibrahim et al (ZooKeys)
An Ambitious Target
The researchers which included Nizar Ibrahim and Paul Sereno (University of Chicago), David Unwin (University of Leicester), Samir Zouhri (Université Hassan II, Casablanca, Morocco) and David Martill (University of Portsmouth), had an ambitious objective. The scientists set out to document and summarise the taxonomic status of the fauna that had been described based on the major collections of Kem Kem fossils, as well as to report on the geological age of the various strata and to plot the palaeoenvironment of this part of north Africa during the early stages of the Late Cretaceous.
The team’s comprehensive report has been published with free access in the journal ZooKeys.
The Changing Palaeoenvironment Represented by the Kem Kem Group Sediments
Schematic paleoenvironmental stages depicting the Kem Kem region during the Cretaceous. Stages: (1) wide rivers, (2) large river systems with substantial sandbanks, (3) deltaic conditions and (4) rise of the limestone platform.
Picture credit: Ibrahim et al (ZooKeys)
A Very Dangerous Place to Be (Large Crocodyliforms and Pterosaurs)
The strata have provided evidence of large number of crocodyliforms from one-metre-long insectivores, herbivorous forms to giant predators such as Sarcosuchus imperator. Several different types of pterosaur are also associated with these deposits. The first pterosaur remains recovered consisted of isolated teeth collected in the late 1940s and early 1950s but at the time their affinity with the Pterosauria was not recognised. For an article from Everything Dinosaur about recent pterosaur discoveries from Morocco: Pterosaurs, Pterosaurs and Even More Pterosaurs.
Cervical Vertebra (Bone from the Neck) Ascribed to an Azhdarchid Pterosaur
Near complete third cervical? of an azhdarchid pterosaur from the Kem Kem Group. FSAC-KK 3088 in (A) ventral, (B) dorsal, (C) right lateral, (D) left lateral, (E) anterior and (F) posterior view. Scale bar equals 5 cm.
Picture credit: Ibrahim et al (ZooKeys)
In addition, the first tapejarid pterosaur from Africa was reported recently (Afrotapejara zouhrii), the trivial name honours Professor Samir Zouhri, one of the authors of the extensive review. To read an article about Afrotapejara: The Fourth New Moroccan Pterosaur – Afrotapejara.
Lots and Lots of Dinosaurs – A Bias Towards the Theropoda
Dinosaurs are strongly associated with these strata, but there is only very fragmentary evidence of ornithischians including a single, large footprint. This suggests that bird-hipped dinosaurs were present but, in contrast to most other Cretaceous biotas, they seem very much underrepresented by the fossil material. Sauropods such as the rebbachisaurid Rebbachisaurus garasbae and titanosaurs are known from both the Douira and Gara Sbaa formations, however, it is theropod specimens that dominate the Dinosauria associated with the Kem Kem Group. There is evidence to support one medium-sized to large Kem Kem abelisaurid and the discovery of single neck bone (cervical vertebra) indicates a Noasauridae presence.
Huge hypercarnivores such as Carcharodontosaurus saharicus and Spinosaurus aegyptiacus have been reported. The habitat seemed to have an overabundance of large, carnivorous dinosaurs, although extensive niche partitioning is proposed by several authors.
Perhaps the Most Famous African Dinosaur of them all – Spinosaurus aegyptiacus
Skull and skeletal reconstruction of Spinosaurus aegyptiacus. Scale bars equal 40 cm in A and B, whilst in C the scale bar is 1 metre.
Picture credit: Ibrahim et al (ZooKeys)
Deltadromeus agilis
One of the most mysterious of all the theropods from Morocco is Deltadromeus agilis. The taxonomic position of this meat-eater remains controversial. A partial skeleton (UCRC PV11), was discovered in a coarse sandstone layer in the upper portions of the Gara Sbaa Formation. The bones were found in association with teeth of the huge sawfish Onchopristis as well as teeth from crocodyliforms. Fossils associated with D. agilis from eastern Morocco show a resemblance to isolated material recovered from the roughly contemporaneous Bahariya oasis in the Western Desert of Egypt by the German palaeontologist Ernst Stromer.
The Egyptian fossils were assigned to the taxon Bahariasaurus ingens, but the Moroccan and Egyptian material could represent the same genus. If this is the case, then D. agilis would become a senior synonym of B. ingens. A single thigh bone from the Bahariya oasis measures 144 cm long. This suggests that whatever sort of carnivore Deltadromeus/Bahariasaurus was, it was huge. Some commentators have suggested that based on femur proportions Deltadromeus could have been only slightly shorter (but more lightly built), than Tyrannosaurus rex.
Holotype of D. agilis (A) and Compared in Size to the Egyptian Femur Specimen (B)
Deltadromeus agilis from Morocco and Egypt. A (A) revised reconstruction based on UCRC PV11 (B) holotype compared to a large femur (now lost) referred to the genus and species from the Bahariya Formation, Egypt. Known elements in white. Scale bars: 1 m.
Picture credit: Ibrahim et al (ZooKeys)
Sadly, like much of Stromer’s material from the Egyptian expeditions, the femur has been lost.
It is very likely that there were lots of smaller predatory dinosaurs too. Dromaeosaurid teeth have been reported from several localities but bones are exceptionally rare and the only positively identified dromaeosaurid skeletal elements are some foot bones found in Sudan and recovered from Cenomanian-age rocks.
A Predominance of Aquatic Predators
The authors state that the Kem Kem assemblage is dominated by aquatic and subaquatic invertebrates and vertebrates, the majority of which are predators. They suggest that as most of the taxa are exploiting aquatic food resources, then like modern marine food chains, the habitat is predator dominated. As to the overabundance of carnivorous dinosaurs compared to plant-eating ones, the researchers conclude that this is not due to sampling bias or preservation factors. Large theropods in the food web were supported primarily in the case of Spinosaurus or secondarily in the case of the terrestrial carnivores by the huge amount of aquatic protein sources.
The dissected deltaic plain and nearshore environments may have enhanced aquatic resources while limiting, or rendering patchy areas of available vegetation for large-bodied dinosaurian herbivores. Hence the bias towards carnivores when it comes to assessing the fossilised remains of dinosaurs from the Kem Kem beds.
The Presence of So Many Carnivores could be Explained by the Abundance of Aquatic Food Sources such as Small Fish
Serenoichthys kemkemensis from the Douira Formation. Scale bar equals 1 cm. The abundance of predators could be explained by the large amount of aquatic protein sources present in the environment.
Picture credit: Ibrahim et al (ZooKeys)
The scientific paper: “Geology and paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco” by Nizar Ibrahim, Paul C. Sereno, David J. Varricchio, David M. Martill, Didier B. Dutheil, David M. Unwin, Lahssen Baidder, Hans C. E. Larsson, Samir Zouhri and Abdelhadi Kaoukaya published in ZooKeys.
Everything Dinosaur received an enquiry earlier this week from a young student studying rocks and fossils at their school as part of a geology project. The student asked, “what is the law of superposition?” Our team members were happy to provide a short explanation.
The principle of superposition, often referred to as the law of superposition is an observation that sedimentary layers of rock at the bottom of a sequence if they undeformed, then they must be older than those at the top. The bottom layers must have been in existence in order to permit the upper layers to have been deposited on top of them.
Layers of Sedimentary Rock Demonstrating the Principle of Superposition
Fossil hunting can be fun but beware of the cliffs. The Church cliffs at Lyme Regis are notoriously unstable and dangerous but they do help to demonstrate the law of superposition.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
A Fundamental Principle of Geology
The law of superposition is regarded as one of the fundamental principles that underpins modern geology, although this principle is very much applicable in other research fields such as archaeology. It helps to provide a basis for the relative dating of strata. As the oldest strata will always be found at the bottom of an undeformed, observable sequence of sedimentary rocks. It is extremely helpful when considering stratigraphical dating, which is governed by the proposition that a layer cannot be older than its constituents.
The introduction of this principle is accredited to the Danish polymath Nicolas Stenos (1638-1686), often referred to as the “father of modern geology”. In 2012, Nicolas Stenos was honoured with the creation of a Google doodle demonstrating his principle complete with illustrations of fossils.
The 2012 Google Doodle Honouring Nicolas Stenos
Remembering the Contribution of Nicolas Stenos. Danish scientist honoured with a Google doodle.
Picture credit: Google
This geological principle was popularised by the famous English geologist William Smith (1769-1839), who used this law to create the first ever map showing the geology of a landscape. In 1815, the year of the battle of Waterloo, William Smith published a map outlining the geology of England, Wales and parts of Scotland.
The “Ground-breaking” First Geological Map to be Published
Can you see the geology in your part of the world?
Massive Edmontosaurus Bonebed Provides Data on Dinosaur Decomposition
A team of scientists have produced a study mapping an astonishing dinosaur bonebed that has so far yielded a staggering total of 13,000 individual fossil elements. In truth, the bonebed contains many more fossils, but individual dinosaur teeth, ossified tendons and other fragmentary elements under five centimetres in length have not been counted.
Edmontosaurus annectens
The site is located in eastern Wyoming and consists almost entirely of the preserved remains of a single type of dinosaur, a hadrosaur (Edmontosaurus annectens). The bonebed study has not only provided a great deal of information about this duck-billed dinosaur but shed light on how death assemblages consisting of a large number of corpses are formed and how various bones of differing sizes might be transported before final deposition.
Dinosaur Bonebeds such as the Danek Edmontosaurus regalis Bonebed in Edmonton Have Yielded Thousands of Fossil Bones
The Danek Edmontosaurus bonebed is typical of an Edmontosaurus-dominated bonebed which are widespread in the Upper Cretaceous (Campanian to Maastrichtian) of western North America).
Picture credit: Victoria Arbour
The Hanson Ranch Bonebed (Lance Formation)
Writing in the on-line, open access journal PLOS One, the scientists which include Keith Synder of the Biology Dept. of the Southern Adventist University, Tennessee, document the taphonomy and depositional history of an extensive E. annectens bonebed known as Hanson Ranch, in the Lance Formation of eastern Wyoming. The bonebed includes five main quarries and three exploratory quarries. Approximately 13,000 elements including around 8,400 identifiable bones, have been recovered in 506 square metres of excavated area in twenty years (1996-2016).
Virtually all the fossils are located within a fine-grained (claystone to siltstone) bed that has a maximum depth of two metres.
Mapping the Stratigraphy of the Main Bonebeds at the Hanson Research Station (Wyoming)
Local stratigraphy associated with the main bonebeds at the Hanson Research station. The green arrow indicates position of main bonebed.
Picture credit: Synder et al (PLOS One) with additional annotation by Everything Dinosaur
Edmontosaurus annectens Fossils in an Excellent State of Preservation
Almost all the fossils recovered from the site exhibit exquisite preservation with little or no abrasion, breakages or signs of weathering prior to deposition. All the material is disarticulated and scattered although over a relatively confined area. This evidence in conjunction with analysis of the sediments associated with the fossils indicates that the bones were moved and buried after a period of initial decay and decomposition of the Edmontosaurus carcasses.
Mapping the Distribution of Fossil Bones in a Bonebed
A map showing typical disarticulated fossil bone distribution in a bonebed.
Picture credit: Synder et al (PLOS One)
Gaining a Better Understanding of Edmontosaurus Biostratigraphy
The thousands of fossil bones represent mainly adult or sub-adult specimens. Due to the huge number of fossils associated with the Hanson Research site, the scientists have been able to gain a deeper understanding of Edmontosaurus biostratigraphy including how elements from the skeleton can be transported over distances prior to deposition. The most abundant fossil bones are ischia, pubes, scapulae, ribs and limb bones. In contrast, vertebrae, ilia and chevrons are rare.
Explaining the Composition of the Bonebed
When it comes to cranial material lower jaw bones (dentaries), nasals, quadrates and jugals are prevalent whilst premaxillae (upper jaw bones), predentaries and bones associated with the braincase are seldom found. The researchers suggest that following decay and break-up of the carcase, water action sorted and removed the articulated sections such as the backbone and the smaller bones such as the digits and toes, before, or at the same time, the remaining material was swept up in a subaqueous debris flow that created the final deposit.
The scientists suggest that similar processes may have been at work that created the other hadrosaurid-dominated Upper Cretaceous bonebeds associated with such geological formations as Hell Creek, Two Medicine, Horseshoe Canyon, Prince Creek as well as the Lance Formations of western North America. It is noted that there is a remarkably similar skeletal composition among the fossil bonebeds studied. It is also noted that there is a significant correlation between the hadrosaurid bonebeds and fluvial assemblages representing thanatocoenosis* events seen with modern-day vertebrate death assemblages.
Thanatocoenosis* Explained
Thanatocoenosis refers to a site where a collection of fossils representing a variety of organisms are found together. Such sites are often referred to as death assemblages. The organisms represented at the location may not have been associated in life, but their remains have been transported and deposited together thus forming a fossil bed composed of an extensive amount of fossilised material.
Not All of the Dinosaur Fossils are Edmontosaurus
The bonebed can be described as monodominant as the vast majority of the fossil material found can be assigned to just one species Edmontosaurus annectens. Non-dinosaurian terrestrial taxa identified include mammals and squamates along with the remains of many aquatic creatures such as crocodiles, turtles, gar and other fishes and numerous molluscs. Some other types of plant-eating dinosaur are represented notably, ceratopsids, pachycephalosaurs, nodosaurs and members of the family Thescelosauridae. Numerous shed theropod teeth are also associated with this location.
Everything Dinosaur will post up a separate article detailing one rather special theropod fossil associated with a quarry close to the Hanson Research station in the near future.
A Life Reconstruction of the Hadrosaurid Edmontosaurus
The new for 2020 Wild Safari Prehistoric World Edmontosaurus dinosaur model.
The picture (above) highlights the 2020 Wild Safari Prehistoric World Edmontosaurus dinosaur model.
The scientific paper: “Over 13,000 elements from a single bonebed help elucidate disarticulation and transport of an Edmontosaurus thanatocoenosis” by Keith Snyder, Matthew McLain, Jared Wood and Arthur Chadwick published in PLOS One.
