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/Dinosaur and Prehistoric Animal News Stories

Fossil finds, new dinosaur discoveries, news and views from the world of palaeontology and other Earth sciences.

28 12, 2017

Attenborough and the Sea Dragon

By | December 28th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, TV Reviews|0 Comments

Television Documentary on Ichthyosaurs Scheduled for BBC One

A television documentary exploring the life of a remarkable Ichthyosaur is due to be shown on BBC 1 on the evening of Sunday 7th January.  Entitled “Attenborough and the Sea Dragon”, this hour-long programme follows the excavation of an Early Jurassic Ichthyosaur fossil on the Jurassic Coast of Dorset.  Sir David Attenborough, a keen fossil hunter himself, joins a team of experts as they attempt to excavate the fossilised remains and piece together the life story of an ancient sea monster.

A Computer-Generated Image of an Ichthyosaur

A monster of the deep - Ichthyosaurus.

A computer generated image of an Ichthyosaur.

Picture Credit: BBC Media

A Giant Sea Dragon

The fossilised remains, believed to represent the largest Ichthyosaur known from the British Isles, were discovered by Dorset fossil hunter Chris Moore in 2016.  The documentary programme will include a segment in which the fossil bones are scanned and a replica skeleton of the 200 million-year-old “fish lizard” is created.  By examining the bones, the team hope to bring this prehistoric sea creature’s story to life.

Fossil Hunter Chris Moore with Some Blocks of the Ichthyosaur Material

Dorset Fossil Hunter Chris Moore.

Chris Moore with some of the blocks containing the Ichthyosaur fossils.

Picture Credit: Richard Austin

Chris spotted the fossil material eroding out of a high cliff and the material had to be removed before the winter storms hit, otherwise the rare fossils would have been lost forever.

The extraordinary fossil includes skin impressions, this leads to new revelations about how these predators might have looked.   As the story unfolds, Sir David compares the sea dragon to animals alive today, including dolphins, sharks, crocodiles and turtles.

A 200 Million-Year-Old Murder Mystery

As more of the fossil bones are revealed the scientists make a startling discovery.  This Ichthyosaur did not die of natural causes, it was attacked, but what fearsome beast could have killed this giant?  Using techniques more at home in a police forensics laboratory than a paleo-preparation lab, the team piece together evidence that points the figure of suspicion at another huge Ichthyosaur – a seven-metre-long monster called Temnodontosaurus.

A Replica of a Temnodontosaurus (T. platydon) A Giant, Viviparous Ichthyosaur

CollectA Temnodontosaurus platyodon model.

Detailed Ichthyosaur figure. Temnodontosaurus platyodon.

Picture Credit: Everything Dinosaur

Using state of the art imaging technology and cutting-edge CGI the team build the skeleton and create the most detailed animation of an Ichthyosaur ever made, bringing this Lyme Regis discovery to life as well as reconstructing its fate.

Programme Details

The one-hour television documentary is confirmed for BBC One on Sunday 7th January 8pm to 9pm.

It’s going to be well-worth watching.

27 12, 2017

Christmas Present for Chinese Palaeontologists

By | December 27th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Clutch of Chinese Dinosaur Eggs for Christmas

News agencies from China are reporting that Chinese palaeontologists have been given a special Christmas present with the discovery of the fossilised remains of a clutch of dinosaur eggs that date from the Early Cretaceous.  Construction workers were examining large boulders that had been blasted away as part of the preparations for a building project in Dayu County (Jiangxi Province, south-eastern China), when they noticed the series of white, semi-circular marks in the sandstone rocks, along with a number of almost complete oval-shaped eggs.

A Close View of One of the Better Preserved Chinese Dinosaur Egg Fossils

A fossilised dinosaur egg.

A close view of one of the fossilised dinosaur eggs from the Dayu County construction site (Jiangxi Province).

Picture Credit: Ming Kangping/China News Service

December 25th Discovery

The clutch of eggs was found on December 25th.  Excavation work in the immediate vicinity was suspended and the area cordoned off to prevent any further damage to the fossil find.  The fossils were inspected by local scientists under the supervision of the authorities with strict security in order to deter any would-be egg fossil thieves.

Scientists Examine the Fossil Finds in the Company of Officials

The site of the dinosaur egg discovery (Dayu County).

Officials look on whilst local scientists examine the dinosaur eggs.

Picture Credit: Ming Kangping/China News Service

Despite the removal and sale of such ancient artefacts having been made illegal in China, unfortunately, there is still a thriving black market in fossils, especially fossils of dinosaurs.  Everything Dinosaur has reported on several fossil theft cases from China.  For example, earlier this year, Everything Dinosaur reported on the arrest of a Chinese man from Zhejiang Province over the alleged theft of more than eighty dinosaur egg fossils.

To read the story: Dinosaur Egg Thief Suspect Arrested in China

Examining the Fossil Material

Chinese dinosaur egg fossils.

Local scientists examine the dinosaur egg fossils.

Picture Credit: Ming Kangping/China News Service

The Remains of at Least Twenty Dinosaur Eggs

The fossils of more than twenty dinosaur eggs have been taken away to a local museum for further study and preparation.  The site, which is a construction project for a new school, will be inspected closely before further building work takes place in case more fossils are at this location.  A spokesperson for the local museum stated that the fossils are around 130 million years old (Early Cretaceous).

26 12, 2017

Water Bird from the Late Cretaceous

By | December 26th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Maaqwi cascadensis – Diving Bird from the Late Cretaceous

A team of scientists writing in the on-line academic journal PLOS One have named a new species of Late Cretaceous marine bird, based on a single coracoid bone and some fragments representing bones from the wing.  The animal has been named Maaqwi cascadensis and at an estimated 1.5 kilos in weight it was about the same size as your average domestic chicken.  However, this bird is believed to have been adapted to a marine environment, using its legs to paddle around under water in pursuit of fish.

Fossils of birds from the Pacific Coast of North America are exceptionally rare, these marine deposits that form part of the Northumberland Formation have yielded fossil fish, marine reptile remains plus fragmentary elements of terrestrial animals including dinosaur bones, but very few avian fossils.  M. cascadensis was discovered on Hornby Island.  The strata are estimated to represent Late Campanian to Early Maastrichtian deposits (around 73 to 71 million years old).  The fossil specimen consists of a mudstone concretion which contains a right coracoid bone plus fragmentary wing bones (humerus, ulna and radius).

A Map Showing the Location of Hornby Island in British Columbia and the Fossil Site

The location of Hornby Island and the fossil site.

The location of the Late Cretaceous fossil bird find.

Picture Credit: PLOS One

In the picture above (A) provides the geographical setting of British Columbia in Canada, whilst (B) shows the location of Hornby Island in the context of Vancouver Island.  The larger map (C) shows Hornby Island with the Northumberland Formation exposures highlighted in black.  The yellow star in (C) shows the location of the fossil discovery.

An initial description of the fossil material had been published previously (2011), but it was only with further cleaning and preparation that the full extent of the fossil material became known.

Photographs and Accompanying Line Drawings of the Fossil Material

Views and line drawings of the Maaqwi cascadensis fossil material.

Photographs and accompanying line drawings of the fossil material.

Picture Credit: PLOS One

In the picture (above) photograph (A) shows the dorsal face of the right coracoid and the partial humerus (c and h) with an accompanying line drawing (B).  Photograph (C) shows the reverse side of the fossil (ventral) revealing more of the wing bones (u = ulna and r = radius).  A line drawing of the reverse side of the fossil is provided (D).  Note the scale bar (1 cm).  In the line drawings white shading denotes preserved cortical bone (dense bone found towards the outside of bones), whilst the light grey shading shows exposed trabecular bone (spongy internal bone).  The dark grey/black represents the mudstone matrix.

Robust Bones and Short Wings

The size of the coracoid bone suggests a large bird, one weighing around 1.5 kilos.  The bones are robust with thickened walls, suggesting that this prehistoric bird was adapted for diving, such as modern grebes and loons.  The coracoid (part of the shoulder bones), is very reminiscent of the coracoid of extant diving birds (Gavia immer – the Common Loon).

A Comparison of Coracoid Bones Mcascadensis Compared to Gavia immer

Comparing coracoids - Maaqwi cascadensis compared to the coracoid of an extant bird (Common Loon - Gavia immer).

The digital reconstruction of the coracoid of Maaqwi cascadensis compared to the coracoid of an extant bird (Common Loon – Gavia immer).  Scale bar = 1 cm.

Picture Credit: PLOS One with additional notation by Everything Dinosaur

An assessment of the arm bones (ulna, radius and humerus) suggests that M. cascadensis had short wings.  It is not known whether this bird was flightless, the wings were probably not the main means of propulsion through water.  It has been speculated that the feet were used to propel the bird underwater, in a similar way to the swimming action of cormorants, if this is the case, then Maaqwi probably had webbed feet.  The research team propose that this bird was a member of the Ornithurae, a natural group which includes the common ancestor of Ichthyornis, Hesperornis and all modern birds.  The generic name, Maaqwi, is derived from “ma’aqwi”, from the language of the indigenous Coast Salish people of the North-west Pacific.  The word means “water bird”.   The specific name or trivial name, cascadensis, reflects provenance in the Cascadia region of western North America.

The scientists including Nicholas Longrich (University of Bath), propose that Maaqwi cascadensis might have been a sister taxon to Vegavis iaai of the Antarctic and along with the Ichthyornithes and Hesperornithes, Mcascadensis and Vegaviidae appear to represent a third clade of bird that evolved to exploit marine habitats in the Late Cretaceous.

To read an article about the voice box of Vegavis iaai: Ancient Bird Voice Box Sheds Light on the Voices of Dinosaurs.

A Speculative Illustration of a Diving Maaqwi cascadensis

Maaqwi diving to catch fish.

M. cascadensis diving.

Picture Credit: Everything Dinosaur

19 12, 2017

Dinosaur Footprint Vandalised

By | December 19th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Australian Dinosaur Footprint Damaged

Vandals have severely damaged a 115-million-year-old dinosaur footprint in an Australian national park.  The park in question is the Bunurong Marine Park in Victoria, the three-toed footprint had been discovered in 2006, but rather than have the rare print removed to a museum, it was decided to leave it in situ allowing all the Park visitors to enjoy it.  Sadly, a person or persons unknown attacked the track with a hammer sometime last week and broke off elements from the toes.

The Dinosaur Footprint that has been Damaged

Vandalised dinosaur footprint.

Theropod footprint vandalised in Australia.

Picture Credit: Parks Victoria

The picture shows (left) the undamaged footprint and (right) a picture showing that the tips of the toes have been smashed, note the boot for scale.  The Flat Rocks locality near Inverloch (Victoria),  is exceptional in being one of only a handful of polar dinosaur sites in the world, it includes the dinosaur footprint.  Palaeontologists from Museum Victoria and Monash University made a silicon rubber mould of the footprint, when the track was discovered, but they decided it should be left in the rock, so visitors to the site could have the thrill of seeing it in its natural state.

Theropod Dinosaur

The tridactyl (three-toed print), probably represents a track left by a Theropod dinosaur.  Parks Victoria are investigating this incident and have appealed for witnesses.

Parks Victoria Ranger Team Leader Brian Martin stated:

“It is sad to think a person or persons who knew the location of the footprint would deliberately damage an important local icon that is recognised as being off international scientific significance.”

Bunurong Environment Centre Education Officer, Mike Cleeland added:

“The thrill of seeing a real dinosaur footprint has been diminished with the callous act of vandalism.  Fortunately, I was able to retrieve some of the broken pieces of the footprint and hopefully the technicians at Museum Victoria may be able to restore the footprint to some degree.”

The location, known as Dinosaur Dreaming is popular with tourists, the Park officials are hopeful that witnesses to the incident will come forward.  Although repairs to the track can be made, the print will never be the same again.

A spokesperson from Everything Dinosaur commented:

“Sadly, such incidents are all too common.  At this stage it is unclear whether this was a clumsy attempt to remove the print or just simply a case of a deliberate act of vandalism on something that was formed in the Lower Cretaceous, a fossil that has survived for 115 million years only to be smashed in seconds.”

To read an article about an alleged attempt to illegally cast a fossil footprint on the Isle of Skye: Dinosaur Footprints Damaged

For a story about the stealing of a dinosaur footprint from Utah: Dinosaur Footprint Stolen

17 12, 2017

New Troodontid Dinosaur Described

By | December 17th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|2 Comments

Almas ukhaa – Named after the Legendary Asian Bigfoot

A team of international scientists, including Dr Mark Norell (Curator of Palaeontology at the American Museum of Natural History, New York) and Professor Xing Xu (Chinese Academy of Sciences), have announced the discovery of a new species of Late Cretaceous troodontid from Mongolia.  This small, carnivorous dinosaur (it was probably less than a metre long), has been named Almas ukhaa, after the mythical Bigfoot-type ape that, according to some cryptozoologists, is believed to roam the more remote parts of Central Asia.

An Illustration of the New Troodontid Dinosaur A. ukhaa

Almas ukhaa illustrated.

An illustration of the newly described (2017) troodontid Almas ukhaa.

Picture Credit: Everything Dinosaur

From the Famous Djadokhta Formation

The fossil material which consists of an almost complete and articulated skull with an associated lower jaw and a substantial part of the postcranial skeleton, comes from the Ukhaa Tolgod region of the Gobi Desert, an area regarded as one of the richest concentrations of Cretaceous fossil vertebrates known to science.   Since this location was first mapped in 1993, numerous dinosaur skeletons have been found, including a nesting Oviraptor as well as several examples of Late Cretaceous mammals.  The rocks in this area form part of the Djadokhta Formation.

The Skull and Jaws of the Newly Described Late Cretaceous Troodontid Almas ukhaa

Almas ukhaa fossil skull and jaws.

Almas ukhaa cranial material (right lateral view).

Picture Credit: The American Museum of Natural History

Compared to other troodontids from Asia and North America, A. ukhaa had a relatively short snout.  The orbit is quite large, and these fossils could represent a juvenile, but if this turns out to be the remains of an adult animal, then this large eye-socket could indicate an adaptation to hunting in low light, perhaps Almas ukhaa was an elusive animal rarely seen in daylight, similar to the legendary Alma after which, this dinosaur is named.

Ukhaa Tolgod Sandstone Deposits

The sandstone deposits of Ukhaa Tolgod date from approximately 80 million years ago, (Campanian faunal stage of the Late Cretaceous).  The highly fossiliferous site was discovered by a joint American/Mongolian expedition in 1993.  Almas ukhaa (pronounced Al-mass ook-uh) is unlikely to be the last dinosaur found in this area.  The fossils show a number of autapomorphies (unique characteristics), that distinguish this southern Mongolian troodontid from other Asian members of the Troodontidae.  For example, the ischium (part of the hip girdle), has a distinct spike-like process and unlike other troodontids, the front part of the lower jaw lacks a lateral groove.

The scientific paper: “Osteology of a New Late Cretaceous Troodontid Specimen from Ukhaa Tolgod, Ömnögovi Aimag, Mongolia.”

14 12, 2017

A Blood-sucking Story – Dinosaur Parasites

By | December 14th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Dinosaur Parasites Preserved in 99-million-year-old Amber

Fossilised ticks discovered trapped and preserved in amber show that these parasites sucked the blood of feathered dinosaurs almost 100 million years ago, according to a new article published in the scientific journal “Nature Communications”.  The amber nodule containing the blood-sucking ticks provides the first direct evidence to support the idea that feathered dinosaurs, just like birds today, had to endure blood-sucking parasites.  As a result of this research, a new species of tick has been named “Dracula’s terrible tick” – Deinocroton draculi.

Modern ticks pass diseases onto their host, this discovery provides evidence that as well as having to deal with parasites, it is likely these ticks and their feeding resulted in the transmission of disease from the invertebrate to their dinosaur host.

The Discovery of Blood-sucking Ticks in Association with Dinosaur Feathers

Fossil evidence of dinosaur parasites.

Evidence of ticks feeding on dinosaur blood preserved in amber.

Picture Credit: Nature Communications

The image above shows the hard tick identified as Cornupalpatum burmanicum entangled in a pennaceous feather.  Photograph (a) shows an image of the amber nodule, scale bar 5 mm, the area in the white box is highlighted in (b) allowing the tick that was entangled in the barbs of the feather to be clearly seen (scale bar 1 mm).

Photograph (c) shows a close-up view of the tick’s capitulum (feeding apparatus), the teeth are highlighted by a black arrow (scale bar 0.1 mm).  Picture (d) shows a view of a barb on the feather, scale bar 0.2 mm, whilst the line drawing (e) shows a dorsal view of the tick and the entangled legs.  Photograph (f) shows a close-up view of the hooklets associated with the barb on the feather, the tick became ensnared in these hooklets and trapped, scale bar 0.2 mm.

Fossils of parasites are extremely rare, especially those found with direct evidence which suggests their host.  However, preserved inside a piece of Burmite (amber from Myanmar), which was formed around 100 million-years-ago, researchers found the perfectly preserved remains of a tick tangled up in a feather along with the remains of other ticks, providing a valuable insight into the lives of feathered dinosaurs.

Jurassic Park Scenario?

Although the tick may contain dinosaur blood, the antiseptic and antibacterial properties of the amber (after all, amber is preserved tree resin and this resin is produced by certain types of trees to protect them from infection), all attempts to identify organic remains such as dinosaur DNA from amber have proved unsuccessful.

Lead author of the study,  Enrique Peñalver from the Spanish Geological Survey (IGME), explained the significance of the fossil find:

“Ticks are infamous blood-sucking, parasitic organisms, having a tremendous impact on the health of humans, livestock, pets, and even wildlife, but until now clear evidence of their role in deep time has been lacking.”

Remarkable Amber from Myanmar

Over the last few years, a number of remarkable fossil discoveries have been made as scientists study amber nodules from Myanmar (formerly known as Burma).  For example, in December 2016, Everything Dinosaur reported on the discovery of a partial dinosaur tail preserved in amber, whilst in June 2017, this blog site reported upon the discovery of the remains of a baby prehistoric bird that also became entombed in amber.

Dinosaur tail found in Burmite: The Tale of a Dinosaur Tail

Baby Bird (Enantiornithine bird) preserved in amber: Watch the Birdie! Enantiornithine Bird Preserved in Amber

The amber was formed in the early part of the Cenomanian faunal stage of the Late Cretaceous.  Northern Burma was covered in a temperate forest during this phase of the Cretaceous, tree resin trapped all kinds of creatures and plant material providing palaeontologists with a fascinating insight into the flora and fauna of a Cretaceous ecosystem.  The researchers identified five different ticks, one is grasping the dinosaur feather and has been identified as an example of Cornupalpatum burmanicum, a tick belonging to the Ixodidae family.  It was a “hard” tick, it had a tough shield (scutum) on its back which protected the Arthropod from predators.  The others including one engorged with blood have been assigned to the new species Deinocroton draculi.

Illustrations of Two of the Ticks (Male and Female D. draculi)

Illustrations of male and female Cretaceous Ticks (D. draculi)

Deinocroton draculi – male (top) with a blood engorged female (bottom).

Picture Credit: Nature Communications

Co-author of the study, Dr Ricardo Pérez-de la Fuente (Oxford University Museum of Natural History) commented:

“The fossil record tells us that feathers like the one we have studied were already present on a wide range of Theropod dinosaurs, a group which included ground-running forms without flying ability, as well as bird-like dinosaurs capable of powered flight.  So, although we can’t be sure what kind of dinosaur the tick was feeding on, the Cretaceous age of the Burmese amber confirms
that the feather certainly did not belong to a modern bird, as these appeared much later in Theropod evolution according to current fossil and molecular evidence”.

Engorged with Blood

The tick that has recently fed shows an eight-fold increase in body volume.  This suggests that D. draculi fed quickly.  It will not be possible to analyse the blood as this tick was only partially immersed in the sticky tree resin and during the fossilisation process the body contents were altered by mineral deposition.  Indirect evidence of a probable dinosaur host is provided in the form of hair-like structures (setae) from the larvae of skin beetles (dermestids), found attached to the other two Deinocroton ticks preserved together.  Dermestids feed in nests, on debris such as shed feathers, skin and hair from the nest’s residents.  As no mammal hairs have yet to be found in Burmite (or indeed any Cretaceous amber), the presence of skin beetle setae on the two Deinocroton draculi specimens suggests that the ticks’ host was a feathered dinosaur.

A Three-dimensional Model of the Newly Described Cretaceous Tick (Deinocroton draculi)

Deinocroton draculi image.

A three-dimensional model of the newly described blood-sucking tick Deinocroton draculi.

Picture Credit: Oscar Sanisidro (University of Kansas)

Another author of the scientific paper, Dr David Grimaldi (American Museum of Natural History, New York) explained:

“The simultaneous entrapment of two external parasites – the ticks – is extraordinary, and can be best explained if they had a nest-inhabiting ecology as some modern ticks do, living in the host’s nest or in their own nest nearby.”

The discovery of these ticks provides indirect and direct evidence that ticks have been parasitising and sucking the blood from dinosaurs within the evolutionary lineage leading to extant Aves for almost 100 million-years.

The scientific paper: “Ticks Parasitised Feathered Dinosaurs as Revealed by Cretaceous Amber Assemblages” by Enrique Peñalver, Antonio Arillo, Xavier Delclòs, David Peris, David A. Grimaldi, Scott R. Anderson, Paul C. Nascimbene & Ricardo Pérez-de la Fuente published in the journal “Nature Communications”.

Everything Dinosaur acknowledges the help of a press release from the Oxford University Museum of Natural History in the compilation of this article.

13 12, 2017

The First Triassic Plesiosaur

By | December 13th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

The Oldest Plesiosaur in Town – Rhaeticosaurus mertensi

Following the end-Permian mass extinction event, the world’s ecosystems took several million years to recover.  In marine environments, just as on land, the mass extinction event led to devastating losses, it has been estimated that 57% of marine families died out.  However, as the Triassic progressed, a number of terrestrial reptiles adapted to marine habitats and new, diverse ecosystems evolved.  It had long been suspected that the Plesiosauria (the long-necked Plesiosaurs and the big-headed Pliosaurs), the most diverse and longest-lived of all the extinct marine reptile groups, had their origins in the Triassic, but the fossil evidence for basal Plesiosaurs was somewhat lacking.  However, the discovery of a partially articulated fossil in a clay pit, close to the village of Bonenburg in North Rhine-Westphalia (Germany), has helped to plug a gap in the fossil record.

The Fossilised Remains of the World’s Oldest Plesiosaur

Rhaeticosaurus fossil (A) with line drawing below (B).

Rhaeticosaurus fossil (A) with line drawing (B).

Picture Credit: Georg Oleschinski

The fossil discovery marks the first Plesiosaur specimen to be recovered from Triassic-aged rocks.  It is the oldest Plesiosaur to be found to date, the only one which dates from the Triassic Period.

Intriguingly, a study of cross-sections of some of the larger fossilised bones in the 2.37-metre-long skeleton, support previous research that suggests these marine reptiles grew rapidly and were (most likely), warm-blooded.  The new species has been named Rhaeticosaurus mertensi, (ree-ti-co-sore-us mur-ten-see), the genus name comes from the last faunal stage of the Triassic (the Rhaetian), the trivial name honours  private collector Michael Mertens, who made the initial fossil discovery.

201 Million-Year-Old Fossil

Michael Mertens discovered the specimen in 2013, some of the neck bones had been lost but the majority of the skeleton was in situ.  The resulting excavation, study and publication in the academic journal “Science Advances”, is a credit to the parties involved, namely Herr Mertens, the natural heritage protection agency, the Münster museum, and scientists from various institutes including Bonn University, the Osaka Museum of Natural History, the University of Tokyo and the Natural History Museum of Los Angeles County, amongst others.

Co-author of the Scientific Paper Tanja Wintrich with the Fossil Finder Michael Mertens

Rhaeticosaurus fossil discovery.

PhD student Tanja Wintrich with Michael Mertens show where the fossil was found.

Picture Credit: Professor Martin Sander (University of Bonn)

The Long-lived and Diverse Plesiosauria

In a press release from Bonn University, Plesiosaurs are described as especially effective swimmers.  They evolved a unique, four-limbed propulsion using broad flippers, in essence, “flying underwater”.

One of the authors of the scientific paper Professor Martin Sander explained:

“Instead of laboriously pushing the water out of the way with their paddles, Plesiosaurs were gliding elegantly along with limbs modified to underwater wings.  Their small head was placed on a long, streamlined neck.  The stout body contained strong muscles keeping those wings in motion.  Compared to the other marine reptiles, the tail was short because it was only used for steering.  This evolutionary design was very successful, but curiously it did not evolve again after the extinction of the Plesiosaurs.”

An Illustration of a Typical Long-necked Plesiosaur

Plesiosaurus.

An illustration of a Plesiosaurus.

Bone Histology Suggests Rapid Growth and Potential Endothermy

The Triassic Plesiosaur already has the typical long-necked Plesiosaur bauplan and it was, like most of its descendants, a pelagic piscivore (an active swimmer, hunting fish).  Analysis of the bone structure indicates that the specimen represents a juvenile, one that was growing rapidly.  Thin cross-sections of fossil bone were compared to Jurassic and Cretaceous specimens and the team’s findings support the hypothesis that to grow this quickly, these reptiles needed to be warm-blooded.

Professor Sander stated:

“Plesiosaurs apparently grew extremely fast before reaching maturity.  Since Plesiosaurs spread quickly all over the world, they must have been able to regulate their body temperature to be able to invade cooler parts of the ocean.”

The Hind Leg Bones of Rhaeticosaurus mertensi

Hind leg bones of Rhaeticosaurus.

Left femur (f), tibia (ti) and fibula (fi). The proximal femur is a cast because the original was sectioned for histology (scale bar = 1 cm).

Picture Credit: Science Advances

In the photograph (above), the part of the femur (f) is a cast as this bone was cross-sectioned as part of the bone study.

Filling a Gap in the Fossil Record

The evolution of the Plesiosauria is poorly understood.  They are probably descended from a group of long-necked, marine reptiles known as Pistosaurs, fossils of which are associated with Middle to Late Triassic deposits.  An example of a Pistosaur is Bobosaurus (B. forojuliensis) from the Rio del Lago Formation of Italy (Carnian faunal stage of the Triassic).  However, Bobosaurus lived some thirty million years before Rhaeticosaurus evolved.  This German fossil discovery helps to fill in a little of the temporal gap in the fossil record of this successful lineage.  Rhaeticosaurus has been assigned to a basal position within the Pliosauridae family and its discovery reveals that the diversification of the Plesiosauria was a Triassic event and a number of genera survived the end Triassic extinction into the Jurassic.  The researchers conclude that the bone histology of this Late Triassic marine reptile suggests that the evolution of fast growth and an elevated metabolic rate were adaptations to an active, pelagic life-style foraging in open water.

Articulated Cervical Vertebrae (C) and Elements from the Left Front Limb (D)

Neck bones (c) and forearm, hand bones of Rhaeticosaurus.

Cervical vertebrae (C) and the left radius (ra), a phalanx (ph) and a (cr) carpal element (D).

Picture Credit: Science Advances

The new specimen corroborates the hypothesis that the open ocean life of Plesiosaurians facilitated their survival of the end-Triassic extinction.

The scientific paper: “A Triassic Plesiosaurian Skeleton and Bone Histology Inform on Evolution of a Unique Body Plan” by Tanja Wintrich, Shoji Hayashi, Alexandra Houssaye, Yasuhisa Nakajima and P. Martin Sander published in the journal “Science Advances”.

11 12, 2017

Looking at the World’s Oldest Eye

By | December 11th, 2017|Dinosaur and Prehistoric Animal News Stories, Main Page, Photos/Pictures of Fossils|0 Comments

Insight into Evolution of the Compound Eye

A team of international scientists including researchers from Cologne University, Estonia and the University of Edinburgh have been looking into the evolution of the first eyes by studying the remarkably well-preserved remains of an eye from a trilobite that lived in the sea more than half a billion years ago.  The trilobite to which it belongs (Schmidtiellus reetae), comes from a fossiliferous zone where the first complete, large organisms appear in the fossil record.  As a consequence of this, it is probably the oldest record of an ophthalmic system likely to be discovered.

Unlike modern compound eyes, the eye of this trilobite had no lens.  The fossil is estimated to be around 530 million years old.

The Trilobite Fossil Providing an Insight into the Evolution of Eyesight

Schmidtiellus reetae fossil.

Schmidtiellus reetae fossil showing details of the eyes.

Picture Credit: G. Baranov (University of Cologne)

Schmidtiellus reetae – Fossil from Estonia

The research team, which included Dr Brigitte Schoenemann (University of Cologne) and her colleagues Helje Pärnaste (Tallinn, Estonia) and Euan Clarkson (Edinburgh University), examined the specimen (S. reetae) and examined the cellular structure of the compound eye.  This remarkable fossil shows how the eye was constructed and from this the team could infer what level of vision the Arthropod had.  As well as looking at similarities with extant Arthropods, the researchers were keen to see how the trilobite eye differed in structure and complexity.  The results show that modern compound eyes work in ways strikingly similar to those of half a billion years ago.  They are very conservative in their structure – and quite successfully so.

Dr Schoenemann commented:

“The principle of the modern compound eye most likely goes back to before the times of our first fossil records.  Half a billion years ago, it was in the early stage of its development, and with our work we have succeeded in uncovering the first visible steps of this extremely successful visual principle”.

Trilobite from Estonia

The fossil comes from Lower Cambrian sediments located in Estonia.  The bedding planes at this location reveal some of the very first fossils of complex animals with an exoskeleton.  The right eye of the trilobite is slightly abraded, allowing for a view into its interior.  It is a typical compound eye consisting of approximately 100 sub-units placed relatively far apart compared to modern forms of compound eyes.  The authors were able to show that each of these sub-units (ommatidia) consists of about eight sensory cells, just like modern compound eyes, grouped around a central rhabdom, a light-guiding receptive structure.  The rhabdom contains the visual pigments and conveys the brightness of the surrounding environment to the animal’s central nervous system.

The Right Eye of Schmidtiellus reetae from the Study

A view of the trilobite eye.

A lateral view of the right eye of the trilobite.

Picture Credit: G. Baranov (University of Cologne)

Dr Schoenemann explained:

“In contrast to the modern compound eyes of bees, dragonflies, and many crabs, this very old compound eye does not have a lens.  This is likely due to the fact that these rather soft-shelled Arthropods lacked the necessary layer in their shell responsible for lens formation.”

What Could the Trilobite See?

The physical features of the central rhabdom ensures that each element of the compound eye has a limited field of vision and that the animal’s overall visual impression already has the mosaic-like character of a modern compound eye.  The precision of such an eye can be determined by the number of its elements, just like the number of pixels determines the precision and detail within a computer image.  The eye was capable of detecting movement and it could roughly discern the distribution of light in its environment to help it avoid obstacles in its path.

The University of Cologne biologist and her team were also able to show that only a few million years after Schmidtiellus lived, new and improved compound eyes with higher resolution developed in another trilobite from the Baltic region called Holmia kjerulfi.  The performance of this species’ eyes even approximated to that seen in modern dragonflies.  A physical analysis of the compound eyes of both trilobites showed that the organism inhabited bright waters, most likely coastal shelf regions.

Looking at the evolution of the Arthropod brain: Arthropod Brain and Nervous System Studied

6 12, 2017

Thornton Triceratops is Actually Torosaurus

By | December 6th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Triceratops Skeleton Turns Out to be Torosaurus

A partial, horned dinosaur skeleton, initially thought to represent a young adult Triceratops has been reassessed following a month of preparation and cleaning and identified as a Torosaurus (T. latus).  It was back in September that Everything Dinosaur first reported on the dinosaur fossil discovery in Thornton, Colorado (USA).  Sadly, the highly respected Denver Museum of Nature and Science palaeontologist, Mike Getty was taken ill at the dig site and passed away shortly afterwards.

Turns out, what was initially identified as a Triceratops has proved incorrect.  As the Denver Museum of Nature and Science preparators have worked on the fossil bones, they have uncovered enough material to confidently ascribe the fossils to the closely related, but much rarer Torosaurus latus.

An Illustration of the Horned Dinosaur Torosaurus latus

Torosaurus illustrated.

An illustration of Torosaurus latus (Sergey Krasovskiy).

Picture Credit: Sergey Krasovskiy

Triceratops and Torosaurus

Analysis of the large head shield that projects backwards from the skull has shown the frill of bone to be quite thin, with two distinct large holes (fenestrae), anatomical traits that are associated with Torosaurus and not Triceratops.  The new diagnosis was made after a careful comparative study using Triceratops specimens already within the Museum’s vertebrate fossil collection.  Torosaurus fossils are exceptionally scarce.  There are several thousand Triceratops (T. horridus and T. prorsus) fossils, representing something like 2,000 individuals.  In contrast, there are approximately 7 partial skulls of Torosaurus known.

A Skeletal Drawing Showing the Extent of the Fossil Material Found at the Thornton Site

Thornton Triceratops turns out to be a Torosaurus.

The yellow parts of the skeleton represent those elements of the Torosaurus found.

Picture Credit: Denver Museum of Nature and Science

A spokesperson for Everything Dinosaur commented:

“The fossil find at Thornton is highly significant.  The majority of the front-end of the individual has been excavated including an almost complete skull.  This specimen may provide palaeontologists with valuable information on how Torosaurus changed as it grew up.  In addition, these fossils could help to identify other Torosaurus specimens in museums that have been misidentified and labelled as Triceratops.”

Is Torosaurus Just a Very Old Triceratops?

The lack of Torosaurus fossil material compared to other horned dinosaurs from North America, led to speculation that Torosaurus was not a valid genus, that the fossil material ascribed to Torosaurus actually represented very old, very mature examples of Triceratops.  The Thornton specimen seems to represent a young adult animal, this may help to clarify the Torosaurus versus Triceratops debate.

To read an article published in 2010, that details an American study that suggested that Torosaurus fossils were actually Triceratops: The Extinction of Torosaurus – Second Time Around

Fossilised Bones Being Exposed at the Thornton Dig Site

The fossils of Torosaurus (T. latus).

Parts of the skeleton are exposed (Torosaurus latus).

Picture Credit: Denver Museum of Nature and Science

Joe Sertich (Curator of Dinosaurs at the Denver Museum of Nature and Science), stated:

“Not only is the fossil more complete and better preserved than I imagined, but it has also revealed itself to be something extremely rare.  The Thornton beast is by far the most complete, and best preserved, ever found.”

Nicknamed “Tiny”

The specimen has been nicknamed “Tiny”, but the work of preparing and studying these fossils is no small task.  The material was unearthed at a Saunders Construction site for a new Public Safety Facility.  Cleaning efforts have also revealed several more skull bones and a complete tibia (lower leg bone).  An estimated 95 percent of the skull and at least 20 percent of the skeleton have now been identified, making this the most complete Cretaceous-aged fossil discovered in Colorado.

Visitors to the Museum can observe the fossil preparation process in the Fossil Prep Laboratory, cleaning and preparing is estimated to take several more months.

Joe Sertich at the Dig Site Working on “Tiny” the Torosaurus

Excavating an Torosaurus.

Joe Sertich, curator of dinosaurs, (Denver Museum of Nature and Science) at the dig site (Thornton, Colorado).

Picture Credit: Denver Museum of Nature and Science

We wonder what Mike Getty would have made of it all?

To read more about the sad death of renowned scientist Mike Getty: Highly Respected Palaeontologist Dies at Dig Site

Everything Dinosaur acknowledges the assistance of the press team at the Denver Museum of Nature and Science in the compilation of this article.

5 12, 2017

The Archaeopteryx That Wasn’t

By | December 5th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Ostromia crassipes – The First European Member of the Anchiornithidae

The first fossil of Archaeopteryx to have been discovered, turns out not to represent the “Urvogel” at all.  In a reassessment of the fossil, known as the Haarlem specimen, as it is part of the vertebrate collection housed at the Teylers Museum in Haarlem (Holland), it has been re-described as a small predatory dinosaur belonging to the anchiornithid family.  The dinosaur has been named Ostromia crassipes, the genus name honours the late John Ostrom, who identified the Haarlem specimen as a Theropod and was instrumental in the work that led to the definition of dinosaurs as dynamic, active reptiles.

The Haarlem Specimen – the Holotype of Ostromia crassipes

Ostromia crassipes holotype fossil.

The holotype fossil of Ostromia crassipes, previously thought to represent Archaeopteryx.

Picture Credit: Oliver Rauhut/Ludwig-Maximilians-University (Munich, Germany)

The fossil studied, actually consists of two parts, the counterslab TM 6929 (left) and the main slab (right) TM 6928.

Archaeopteryx was named in 1861, however, the Haarlem specimen was found four years earlier.  To date, around a dozen specimens have been assigned to the Archaeopteryx genus, including a single, fossilised feather.  The discovery of Archaeopteryx supported the theory of natural selection proposed by Darwin and Wallace as it represented a transitional form between reptiles and birds.  Archaeopteryx fossils support the idea that modern birds are descendants of carnivorous dinosaurs.

Writing in the academic journal “BMC Evolutionary Biology”, palaeontologists Oliver Rauhut and Christian Foth from the Staatliches Museum für Naturkunde in Stuttgart have re-examined the Haarlem specimen.  They conclude that this fossil differs in several important respects from the other known representatives of the genus Archaeopteryx.  The researchers conclude that the fossil is not an Archaeopteryx at all, but a representative of the very bird-like maniraptoran dinosaurs known as anchiornithids.

These crow-sized, predatory dinosaurs possessed feathers on all four limbs, and they predate the appearance of Archaeopteryx by several million years.

Commenting on their study, Dr Oliver Rauhut stated:

“The Haarlem fossil is the first member of this group found outside China and together with Archaeopteryx, it is only the second species of bird-like dinosaur from the Jurassic discovered outside eastern Asia.  This makes it [the Haarlem specimen] even more of a rarity than the true specimens of Archaeopteryx.”

Subtle Anatomical Differences and Bone Osteology

The scientists looked at the relative proportions of limb, toe and finger bones and noted that the Haarlem material (TM 6929 and TM 6928), was different from other Archaeopteryx specimens.  In addition, it had affinities with the fossilised remains of Anchiornis from China.  Furthermore, differences in bone osteology were observed.  For example, the Haarlem fossil specimen has a regular, well-developed longitudinal furrow on the exposed medial side of the preserved manual phalanx, this furrow is not present on any of the finger bones ascribed to Archaeopteryx.

Comparing the Finger Bones (Manual Phalanges) of Various Theropods

Theropod manual phalanges comparison.

Comparison of Theropod finger bones in highly compacted sediments.  Scale bar in mm.

Picture Credit: BMC Evolutionary Biology

The photograph (above) shows close-up views of the finger bones (manual phalanges) of several Theropods, analysis of the shape of the bones, their features and their proportions led the researchers to conclude that the Haarlem specimen was not Archaeopteryx.

(a).  the right manus (hand) of the Thermopolis specimen of Archaeopteryx

(b). the right manus of the Solnhofen specimen of Archaeopteryx

(c). the left manus of the juvenile Theropod from Germany Sciurumimus albersdoerferi (image resolved under UV light)

(d). the second finger of the small Late Jurassic Theropod Compsognathus longipes

(e).  the impression from the first finger of the anchiornithid Anchiornis huxleyi

(f). the first finger of Caudipteryx, a feathered Theropod from the Early Cretaceous of China

Learning About Fauna of the Solnhofen Archipelago

Discovered in 1857, the Haarlem fossil specimen was found about 6 miles (10 kilometres), to the north-east of the closest Archaeopteryx locality known (Schamhaupten) which is near the town of Altmannstein in southern Bavaria.  The Jurassic-aged rocks in this area were laid down in a shallow sea, in which were scattered numerous small islands, an archipelago, that provided an environment, superficially similar to that of the Caribbean today.  These islands that once covered southern Bavaria, are known as the Solnhofen archipelago, the region from which all known specimens of the genus Archaeopteryx come from.  The taxonomic reassignment of the Haarlem specimen to the feathered Anchiornithidae has provided a fresh insight into the evolution of the Avialae and indicates that the first bird-like dinosaurs originated in Asia.  During the Middle to the Late Jurassic these creatures migrated westwards, reaching the Solnhofen archipelago of Western Europe some 150 million years ago.

The Haarlem fossil was originally recovered from what was then the eastern end of the archipelago, quite close to the mainland.  Unlike Archaeopteryx, anchiornithids were (most likely), unable to fly, and might not have been able to reach the more remote islands offshore.   All true fossils of Archaeopteryx found to date were recovered from the lithographic limestone strata further to the west, closer to the open sea.  This implies that dinosaurs like Ostromia may have been limited in their distribution, compared to the volant Archaeopteryx.

Faunal Distribution in the Solnhofen Archipelago (Late Jurassic)

The Solnhofen archipelago and Ostromia/Archaeopteryx distribution.

The researchers speculate that the flightless Ostromia could not have reached the islands furthermost from the mainland whilst Archaeopteryx with its powered flight capability was able to reach outlying islands.

Picture Credit: Everything Dinosaur

In the diagram above, Ostromia may have been unable to reach the more remote parts of the island chain whilst Archaeopteryx, which was capable of powered flight (its aerial abilities are still debated), would have been more able to “island hop”.

Based on these new findings, the researchers postulate that other known Archaeopteryx fossils may need reassessment.

Dr Rauhut suggests:

“Not every bird-like fossil that turns up in the fine-grained limestones around Solnhofen need necessarily be a specimen of Archaeopteryx,”

The scientific paper: “Re-evaluation of the Haarlem Archaeopteryx and the Radiation of Maniraptoran Theropod Dinosaurs” by Christian Foth and Oliver W. M. Rauhut published in BMC Evolutionary Biology.

An article on Archaeopteryx research: Archaeopteryx Had Feathered “Trousers”

The oldest Archaeopteryx fossil: The Oldest Archaeopteryx in Town?

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