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Pictures of fossils, fossil hunting trips, fossil sites and photographs relating to fossil hunting and fossil finds.

15 06, 2018

Mexico’s Oldest Member of the Ankylosauria

By | June 15th, 2018|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Acantholipan gonzalezi – Coahuila’s Oldest Dinosaur

A new genus of armoured dinosaur has been described.  This dinosaur roamed northern Mexico around 85 million years ago (the Santonian faunal stage of the Late Cretaceous).  Described as a nodosaurid, the dinosaur has been named Acantholipan gonzalezi and it is the oldest dinosaur described to date from the Coahuila region of Mexico.  Its discovery is no real surprise, some osteoderms (dermal armour), associated with ankylosaurids have been described from the geologically younger (Campanian), Cerro del Pueblo Formation exposed in the Coahuila region.  In addition, a single tooth identified as nodosaurid, has been discovered in the Mexican state of Baja California.  This fossil tooth was found in Campanian-aged deposits.  Palaeontologists had expected that armoured dinosaur fossils would be found elsewhere in Mexico, extending their known range further south.

The Southernmost Nodosaurid from North America – Acantholipan gonzalezi

A life reconstruction of Acantholipan gonzalezi.

A model of the Mexican nodosaurid Acantholipan gonzalezi.

Picture Credit: Museo del Desierto (Mexico)

Identified from Fragments of Bone

Fragmentary fossils found near to the city of Ocampo in northern Mexico, back in 2011, suggested that nodosaurids roamed this part of North America during the Late Cretaceous, but it was thought that the fossil material was not sufficient to support the establishment of a new species.  The fossils consist of a single dorsal vertebra, a tail bone (caudal vertebra), a partial ulna, a fragment of rib, one large spike (osteodermal spine) along with a portion of an upper arm bone (distal end of a humerus).

The Fragmentary Fossil Material (CPC 272)

Acantholipan fossil material.

Fossil fragments representing a nodosaurid from Coahuila, Mexico (Acantholipan gonzalezi).

Picture Credit: Museo del Desierto (Mexico)

The photograph (above), shows the nodosaurid fossil material from Coahuila.  Although very fragmentary, subsequent comparative analysis with younger North American nodosaurids has permitted the establishment of a new species.

Key

Distal end of right humerus in (a) dorsal, (b) ventral, (c) anterior, and (d) posterior views.
Dorsal vertebra in (e) cranial, (f) caudal, and (g-h) lateral views.
Right ulna in (i) dorsal, (j) ventral, and (k-l) lateral views.
Osteodermal spine (m-p).

Note: Scale bar = 5 centimetres

A Skeletal Illustration of A. gonzalezi – Known Fossil Material Outlined in Red

Acantholipan gonzalezi skeletal drawing.

The known bones of A. gonzalezi are shown in red.

Picture Credit: Museo del Desierto (Mexico)

Armoured Dinosaur Bones Found in Marine Shales

The fossil material was discovered in marine shales associated with the Pen Formation.  The research team studying this material have concluded that the carcass of the dinosaur, a juvenile approximately 3.5 metres long, had been swept out to sea, before sinking to the seafloor and becoming buried by sediment.  If this dinosaur had reached maturity, the scientists estimate that it could have reached a length of about six metres and weighed several thousand kilograms.  With the naming of Acantholipan gonzalezi, this dinosaur becomes the oldest member of the Dinosauria described from the Coahuila region, and the first member of the Ankylosauria clade to have been named from Mexican fossils.

Commenting on the new species of armoured dinosaur, José Rubén Guzmán Gutiérrez of the Museo del Desierto and one of the co-authors of the scientific paper describing the dinosaur in the Swiss Journal of Palaeontology, stated:

“Here in Mexico, we have a significant palaeontological wealth, specifically in the state of Coahuila.  We have this palaeontological richness and it is worthwhile for the population to get involved in getting to know this heritage that belongs to all Mexicans.”

The name of this new species of armoured dinosaur honours its Mexican roots.  The genus name comes from the Greek “akanthos”, which means spine, combined with the name of the native Indians which inhabited this part of northern Mexico.  The species name honours Arturo González-González, the director of the Museo del Desierto.

To read an article from 2017 reporting on the discovery of a new species of horned dinosaur from the Coahuila region of Mexico: Yehuecauhceratops – A New Horned Dinosaur from Northern Mexico

14 06, 2018

Everything Dinosaur to Conduct Dinosaur and Fossil Workshops at The Beacon Museum

By | June 14th, 2018|Dinosaur Fans, Everything Dinosaur News and Updates, Main Page, Photos/Pictures of Fossils, Press Releases|0 Comments

Everything Dinosaur at the Beacon Museum

As part of The Beacon Museum’s summer exhibition “Brick Dinos”, team members from Everything Dinosaur will be conducting a weekend of dinosaur and fossil themed workshops.  Join Mike and Sue from Everything Dinosaur from Friday afternoon 27th July and throughout that weekend and help them hunt for fossils including dinosaur bones!  Team members from Everything Dinosaur will be conducting a series of workshops at the Beacon Museum, giving participants the chance to be a palaeontologist and cast museum quality fossil replicas.  Turn dinosaur detective and get up close to some amazing fossils and learn how to find evidence of ancient life. Best of all, what you find on the fossil dig, you can keep!

Join Everything Dinosaur Team Members over the Weekend of July 27th to July 29th

Everything Dinosaur at the Beacon Museum

Everything Dinosaur will be conducting a series of family friendly dinosaur and fossil themed workshops from July 27th – July 29th.

Picture Credit: Everything Dinosaur

Dinosaur Detectives and Perceptive Palaeontologists

The “Brick Dinos” event allows visitors to travel back in time and to interact with a series of prehistoric animal exhibits that have been created by the famous plastic bricks (Lego®).  Everything Dinosaur will be conducting a series of 2-hour-long, family friendly, dinosaur and fossil themed workshops, utilising the ground floor of the Beacon Portal.  Numbers are limited so booking is essential.

Dinosaur and Dino Pro combination tickets available please ring 01946 592302 for details, or alternatively, you can contact the Beacon Museum for tickets and further information: Contact The Beacon Museum at Whitehaven

Mike from Everything Dinosaur commented:

“We are going to be bringing lots of different fossils which have been collected from various dig sites, sharks teeth, corals, ammonites, crocodile armour and of course, real dinosaur bone.  Visitors to the Beacon will have the opportunity to hunt for fossils and you can take home what you find, starting your own fossil collection.”

The Beacon Museum Promoting the Visit of Everything Dinosaur (July 27th to July 29th 2018)

Dinosaur workshops at the Beacon Museum.

Everything Dinosaur visiting The Beacon Museum in July 2018.

Picture Credit: The Beacon Museum (Whitehaven, Cumbria)

The Proposed Itinerary*

Everything Dinosaur team members are going to be very busy over that weekend.   The team intend to conduct a 2-hour dinosaur and fossil workshop on Friday afternoon (starting 2pm) and to delivery two further workshops on Saturday and Sunday morning.  On Saturday and Sunday afternoon, Everything Dinosaur will be laying out their fossil trays and inviting visitors to join them on a fossil hunt, looking for fossils which will include teeth from prehistoric sharks, belemnite guards and dinosaur bones.

Friday 27th July
• 2pm to 4pm – Dinosaurs and Fossils Workshop

Saturday 28th July
• 9.30am to 11.30am – Dinosaurs and Fossils Workshop

• 1pm – Fossil Trays and Finding Fossils

• 2pm – Fossil Trays and Finding Fossils

• 3pm – Fossil Trays and Finding Fossils

• 4pm – Fossil Trays and Finding Fossils

Sunday 29th July
• 9.30am to 11.30am – Dinosaurs and Fossils Workshop

• 1pm – Fossil Trays and Finding Fossils

• 2pm – Fossil Trays and Finding Fossils

• 3pm – Fossil Trays and Finding Fossils

• 4pm – Fossil Trays and Finding Fossils

Proposed itinerary* potentially subject to change contact The Beacon Museum for further information.

Finding Fossils Including Shark Teeth

fossilised shark teeth.

A successful fossil hunt.

Picture Credit: Everything Dinosaur

Further information and tickets: Contact The Beacon Museum at Whitehaven

12 06, 2018

The Pneumatic Bones of Theropods

By | June 12th, 2018|Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

The Pneumatic Bones of Theropods (Living and Extinct)

Air-filled (pneumatic), bones are unique to birds amongst living terrestrial vertebrates.  However, it is known that many different types of Archosaurs as well as the birds had post-cranial bones with lots of air sacs.  Non-avian dinosaurs in the form of the Theropoda had them to.  Whilst visiting the Grant Museum of Zoology and Comparative Anatomy in London, this shared anatomical trait was beautifully demonstrated when viewing a number of avian exhibits.

An Ostrich Femur (Thigh Bone) Showing Pneumaticity

An ostrich femur showing extensive pneumaticity.

A cross-section of an ostrich femur showing the extensive air sacs.

Picture Credit: Everything Dinosaur

The caption in the display case reads:

“OSTRICH FEMUR – Birds have honeycomb bones to reduce weight for flight.  Flightless ostriches evolved from flying birds and retain this feature”.

The above statement is true, but technically (most probably), pneumatic, post-cranial bones have been inherited from the Dinosauria.

A Fragment of Theropod Bone Showing the Highly Pneumatised Internal Structure

The tell-tale honeycomb structure of fossil bone indicates Theropod dinosaur.

A close up of the fossil bone shows the typical honeycomb structure indicative of a Theropod dinosaur.

Picture Credit: Jason Love/Burke Museum

Air-filled Bones Evolved Independently in Several Groups Avemetatarsalia

The fossil record has provided evidence of pneumaticity in Late Triassic Archosaurs (at least 210 million years ago), it is very likely that air-filled bones evolved much earlier in the branch of the Archosaurs (Avemetatarsalia), that includes the dinosaurs, pterosaurs and birds.  Bones with air sacs are also associated with derived members of the Sauropodomorpha.  It has been postulated that this characteristic evolved independently in several groups and that pneumaticity did not occur amongst these different Archosaurs as a result of sharing a common ancestor.

The evolution of light, but strong air-filled bones can be explained for the birds, as such bones would help reduce weight and make flying easier.   As for the other, extinct Archosaurs, this characteristic evolved in the Pterosauria (flying reptiles) for very probably the same reason – to reduce weight to make flying easier.  As for the dinosaurs and other largely non-volant Archosaurs that had this feature, pneumatisation might have evolved to reduce energy expenditure as these animals moved about.  After all, if you weigh several tonnes, as in the case of a basal Sauropod, if you could evolve a more efficient method of locomotion, than this makes a lot of evolutionary sense.

6 06, 2018

Three-toed Dinosaurs from the Tatras

By | June 6th, 2018|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Scientists Discover Dinosaur Footprints in the Tatra Mountains

The beautiful and rugged Tatra mountain range forms a natural border between Poland and Slovakia, but during the Late Triassic, the sediments that formed part of these peaks were sandy shores close to large rivers where many different types of dinosaur wandered.  Dinosaurs left their footprints in these soft sands, and remarkably some of these trace fossils have survived more than 200 million years and they are helping palaeontologists to better understand the composition of Late Triassic vertebrate faunas.  Media reports from the Centre of Interdisciplinary Biosciences of Pavol Jozef Šafárik University in Košice, Slovakia, confirm the discovery of yet more three-toed Theropod dinosaur footprints, although most are badly eroded, these trace fossils indicate the presence of a sizeable predator, one that may have exceeded five metres in length.

The fossils come from the Tomanová Formation and although dating the strata is challenging, the rocks are thought to have been laid down during the Late Norian to the Rhaetian faunal stage of the Triassic (215 – 202 million years ago approximately).

Palaeontologist Martin Kundrát with a Cast of a Dinosaur Footprint

Dinosaur Footprint cast (Tatra Mountains).

Martin Kundrát holding a cast of the dinosaur trace fossil he discovered in the Tatras.

Picture Credit: Jana Otriová

Recording the Activity of Dinosaurs from the Late Triassic

The first dinosaur fossil footprints found in the High Tatras were described in 1976.  These fossils and subsequent footprint discoveries led to the establishment of a new ichnospecies – Coelurosaurichnus tatricus.  However, these new finds, ten dinosaur trace fossils, have helped shed further light on vertebrate fauna at an important time in our planet’s history.  At around this time, a mass extinction event occurred and a number of terrestrial vertebrates (and other types of animal) became extinct, providing the Dinosauria with even greater opportunities to diversify and produce new species.

Commenting on these fossils, one of the palaeontologists who discovered them, Martin Kundrát (Centre of Interdisciplinary Biosciences of Pavol Jozef Šafárik University), stated:

“The locality is extremely rare for Slovak dinosaurology.  It is located at high altitude.  This does not mean, however, that dinosaurs have been hiking.  The truth is that the sediments in which the traces were preserved were created hundreds of kilometres from Slovakia almost at the level of the then advancing sea.  The layers of the tracks were later transported to the territory of Slovakia and raised to the stars.  This is our modest dinosaur association.  Two of them are complete, the rest are only fragments.”

One of the More Complete Footprint Fossils

Dinosaur footprint fossil from Slovakia.

Coelurosaurichnus tatricus?  Footprints previously ascribed to the ichnospecies C. tatricus may have to be redefined in the light of these new fossil discoveries.

Picture Credit: Martin Kundrát

Important Fossils Although Fragmentary Fossils

The fossil record for dinosaurs from Europe during the Late Triassic is relatively poor, so even these fragments are very helpful to palaeontologists as they attempt to piece together the biota of Pangaea.  The trace fossils, although quite indistinct, help scientists to gain an understanding of the various types of dinosaur that roamed this part of the world more than 200 million years ago.  Moreover, these new discoveries allow palaeontologists to revise their knowledge about an ancient ecosystem.   Based on studies of similar imprints from South Korea, the United States, Iran and China, scientists have been able to make two important deductions.

First, the researchers have concluded that the former ichnotaxonomy (classification of an animal based on its footprints, burrows, or other traces) of Coelurosaurichnus tatricus is not valid.

Secondly, the number of imprints confined to a small area indicates that it was a very often frequented locality.

The Dinosaur Footprints Indicate a Theropod Around Five Metres in Length

Liliensternus drawing.

Liliensternus dinosaur drawing,  It is probable that the Slovakian Theropod looked like Liliensternus from the Late Triassic of Germany.

Picture Credit: Everything Dinosaur

In total, this part of the High Tatras has yielded several different types of dinosaur footprint.  Several papers have been published previously describing Ornithischian prints and the large, rounded tracks of what are assumed to be Sauropodomorpha, as well as numerous types of three-toed (tridactyl) prints assigned to the Theropoda.

2 06, 2018

The Mother of All Dragons – Megachirella

By | June 2nd, 2018|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

The Mother of All Dragons – Megachirella wachtleri

A team of international scientists, including palaeontologists from Bristol University, Midwestern University (Arizona) and the University of Alberta, have identified the world’s oldest lizard fossil, permitting fresh insight into the evolution of extant snakes and lizards (Squamata).  Writing in the journal “Nature”, the researchers, including co-author Dr Massimo Bernardi from MUSE – Science Museum, Italy and University of Bristol’s School of Earth Sciences, built the largest dataset of reptiles ever assembled in order to assess where in the evolutionary tree of the Reptilia a fossil from the Dolomites of Italy should be placed.

The Holotype Specimen of Megachirella wachtleri

The origins of the Squamata - The holotype of Megachirella wachtleri.

The holotype of Megachirella wachtleri.

Picture Credit:  MUSE – Science Museum

Megachirella wachtleri

The fossil, consisting of an articulated partial specimen was discovered in marine sediments in the Dolomites of Italy and named Megachirella wachtleri in 2003.  Although, found in marine sediment, the fossil, which represented the front portion of the animal, showed no adaptations to an aquatic existence.  On the contrary, it had strong legs with claws and although small at around twenty centimetres in length, it was probably a capable climber.  It was concluded that the carcass of this reptile had been washed out to sea following a storm.

An analysis in 2013 concluded that Megachirella wachtleri was a member of the Lepidosauromorpha, a group of diapsid reptiles defined as being closer to Squamata than to the Archosauria.  Lepidosaurs include modern snakes and lizards, many extinct forms of reptile and the Order Rhynchocephalia, once very diverse, but now only represented by the tuatara of New Zealand.  This new research, which drew upon an enormous database of skeletal and molecular information about 129 different types of reptile, revealed that Megachirella had characteristics that are only found in the Squamata.  It was concluded that M. wachtleri was a stem squamate – think of it as being the “the mother of all dragons”.

Co-author Dr Randall Nydam of the Midwestern University in Arizona stated:

“At first I did not think Megachirella was a true lizard, but the empirical evidence uncovered in this study is substantial and can lead to no other conclusion.”

The 240-million-year-old fossil, Megachirella wachtleri, is the most ancient ancestor of all modern lizards and snakes discovered to date.  The study also found that geckoes are the earliest crown group squamates not iguanians as previously thought.

A Life Reconstruction of  Megachirella wachtleri

Megachirella wachtleri in the Dolomites 240 million years ago.

A life reconstruction of Megachirella wachtleri.

Picture Credit: Davide Bonadonna

The beautiful illustration of M. wachtleri produced by Davide Bonadonna is featured on the front cover of the journal Nature, which provides details of this scientific study.

The research team conclude that the Squamata probably evolved in the Late Permian and therefore, the ancestors of today’s snakes and lizards survived the most devastating mass extinction event known to science – the end Permian extinction.

Tiago Simões, lead author of the scientific paper and a PhD student at the University of Alberta (Canada), explained:

“The specimen is 75 million years older than what we thought were the oldest fossil lizards in the entire world and provides valuable information for understanding the evolution of both living and extinct squamates.”

10,000 Squamate Species

It has been estimated that there are around 10,000 species of lizards and snakes living today, twice as many different species as mammals.  Despite this modern diversity, scientists did not know much about the early stages of their evolution.

Student Tiago Simões added:

“It is extraordinary when you realise you are answering long-standing questions about the origin of one of the largest groups of vertebrates on Earth.”

Co-author of the study, Dr Michael Caldwell from the University of Alberta, explained that fossils represent the only accurate window into the ancient story of life on our planet.  The new understanding about Megachirella and its significance is but a point in deep geological time, it does tell us things about the evolution of lizards that we simply cannot learn from any of the extant species today.

Co-author Dr Massimo Bernardi from MUSE – Science Museum, Italy and University of Bristol’s School of Earth Sciences, commented upon the importance of such fossil specimens, stating:

“This is the story of the re-discovery of a specimen and highlights the importance of preserving naturalistic specimens in well maintained, publicly accessible collections.”

The scientific paper:

“The Origin of Squamates Revealed by a Middle Triassic Lizard from the Italian Alps” by T. Simões, M. Caldwell, M. Tałanda, M. Bernardi, A. Palci, O. Vernygora, F. Bernardini, L. Mancini and R. Nydam published in the journal Nature.

Everything Dinosaur acknowledges the help of a press release from Bristol University in the compilation of this article.

31 05, 2018

Uruguay’s First Pterosaur

By | May 31st, 2018|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Uruguay’s First Pterosaur

A team of international scientists writing in the academic publication “The Journal of South American Earth Sciences”, have reported the discovery of the first pterosaur fossils known from Uruguay.  The fossil material representing a fragment of jaw with associated teeth, is believed to represent a new species of Ctenochasmatidae pterosaur.  Ctenochasmatids are geographically widespread with fossils reported from the United States, China, southern Germany, Argentina and England.  The fossils ascribed to this family of short-tailed pterosaurs have a large temporal range, from the Late Jurassic transitioning through to the Early Cretaceous.

Views of the Fragmentary Fossil Material (Rostrum)

Ctenochasmatid rostrum from Uruguay.

The first pterosaur fossils from Uruguay.

Picture Credit: The Journal of South American Earth Sciences

Buck-Toothed Pterosaur

The fossil comes from the Tacuarembó Formation, which is believed to represent deposits laid down as the early Atlantic Ocean opened up.  The strata largely consists of  sediments deposited in a terrestrial, near-shore environment.  The orientation of the tooth sockets and the preserved tooth base suggests that the conical teeth were pointed out sideways and forwards.  This may have been an adaptation for capturing slippery prey such as small fish.  This family of small pterosaurs exhibit a variety of different shaped mandibles, although fragmentary, the researchers have identified that the fossil jaw widens towards the tip (anterior portion), the shape of the jaw and its size corresponds to jaws of known ctenochasmatids, specifically the subfamily Gnathosaurinae.

Different Jaw Types within the Ctenochasmatidae

Ctenochasmatid mandible variation.

Ctenochasmatid mandibles.

Picture Credit: Wellnhofer, Howse et al from Witton

The picture shows mandible variation within the Ctenochasmatidae (A) Ctenochasma elegans seen from below, (B) Plataleorhynchus streptorophodon as viewed from below and (C), the skull of Gnathosaurus subulatus (viewed from underneath).  The dentition and the shape of the mandibles suggest adaptations for catching and consuming different types of prey.

Dating the Geological Formation Thanks to a Shark

The Tacuarembó Formation has proved very difficult to date, as the fossils found in the strata were not that easy to compare to fossils found in other rocks.  Despite, an abundance of bone fragments representing a range of creatures, including Theropod dinosaurs, the Tacuarembó Formation lacked helpful biostratigraphic indicator fossils to assist with relative dating.  This changed with the discovery of numerous teeth and a single dorsal spine which was assigned to the Hybodont shark Priohybodus arambourgui.  Fossils of this primitive shark are known from the Arabian Peninsula as well as Africa and the strata associated with these fossils has permitted more accurate dating to occur.  Thanks to this shark, the authors of this new paper can state that the pterosaur fossil material comes from a fossiliferous horizon no older than the Late Jurassic.  As such, the Uruguayan pterosaur remains represent the oldest ctenochasmatid found in South America known to science.

12 05, 2018

Saurornitholestes from Appalachia?

By | May 12th, 2018|Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Saurornitholestes from the South-eastern United States

Whilst in the course of writing the fact sheets for all the new dromaeosaurid models that are due to arrive when the “Beasts of the Mesozoic” stock comes in, team members have come across some fascinating information relating to Saurornitholestes langstoni.  This member of the Dromaeosauridae, which was similar to Velociraptor, was originally described in 1978 from fossil material found in southern Alberta.   Dromaeosaurids such as Saurornitholestes, or at least related species, may have roamed the south-east of the United States as well as the western USA and Canada.

A Single Tooth from Alabama (Saurornitholestine dromaeosaurids)

Dromaeosaurid tooth from Alabama.

The isolated dromaeosaurid teeth with very different sized denticles (anterior and posterior).

Picture Credit: David R. Schwimmer

Isolated Dromaeosaurid Dinosaur Teeth

Isolated teeth have been found in North and South Carolina and assigned to the Saurornitholestes genus, or at least described as having come from Saurornitholestine dromaeosaurids.  The picture above shows a tooth assigned to  Saurornitholestes langstoni that was found in Greene County (Alabama), from exposures representing the Upper Cretaceous (Mooreville Formation).  The tooth measures about 4.6 mm long and it shows the distinctive serrations (denticles) associated with the Saurornitholestes genus.  The denticles on the posterior (back) edge of the teeth are much more prominent and larger than those denticles found on the anterior (front) edge of the tooth.  This extreme disparity is regarded as a unique feature of Saurornitholestine dromaeosaurids.

During the Late Cretaceous, North America was split into two landmasses by the Western Interior Seaway.  To the west was Laramidia and to the east, the far larger landmass of Appalachia, although much more is known about the Cretaceous biota of Laramidia.

A far larger tooth, one that measures more than 20 mm in length was found in North Carolina.  This tooth also showed the characteristic disparity in denticle size between the anterior and posterior carinae (the sharp edges of the teeth).  This fossil find suggests that dromaeosaurids of different sizes roamed Appalachia during the Late Cretaceous.

The Beasts of the Mesozoic Saurornitholestes langstoni Figure

Beasts of the Mesozoic Saurornitholestes langstoni.

The Beasts of the Mesozoic Saurornitholestes langstoni “raptor” figure.

Picture Credit: Everything Dinosaur

When it comes to the Saurornitholestes genus in particular, these types of characteristic teeth are known from numerous sites across North America and from rock formations that vary in age by millions of years.  Either Saurornitholestes langstoni and Saurornitholestes sullivani, the two species currently assigned to this genus, were geographically and temporally widespread, or there are a lot more dromaeosaurid species, including quite large ones, if the North Carolina tooth is anything to go by, awaiting discovery.

9 05, 2018

A Weather Forecast from the Cambrian

By | May 9th, 2018|Dinosaur and Prehistoric Animal News Stories, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Tiny Fossils Provide Clues to Earth’s Climate 500 Million Years Ago

A joint team of scientists from France and the UK, have plotted the temperature of our planet’s oceans over half a billion years ago using a combination of fossil data and computer-based climate models.  Think of it as a sort of weather forecast from the Cambrian.  This newly published research suggests that the first hard-bodied animals diversified in warms seas, heated by a greenhouse world.  The team’s findings help to expand our knowledge of the environment at the time of the Cambrian explosion, a period in Earth’s history that saw a huge increase in the number and type of marine animal forms.

Life in the Late Cambrian Period

Cambrian life.

Life in the Late Cambrian by Zdeněk Burian.

Picture Credit: Zdeněk Burian

Writing in the academic journal “Science Advances”, the scientists, led by researchers from the University of Leicester, used climate models and the chemical analysis of tiny, shelly fossils preserved in limestone from Shropshire (central England), to calculate the sea temperature during a time of rapid diversity of animal life in the Palaeozoic.  From around 540 to 510 million years ago, the fossil record shows a marked change, as during this period of Earth’s history, virtually all of the animal phyla (including the Chordata – our phylum) appeared.  The idea of a “Cambrian explosion” is a little misleading, the appearance of many new forms of complex animal life may have been gradual, but in terms of the fossil record, sites such as the famous Burgess Shale of British Columbia and Yunnan Province (southern China), have revealed extensive and varied marine ecosystems with large numbers of new types of animal being recorded in the strata.

Analysis of Some of the First Shelly Fossils

Scientists had thought that for much of the Cambrian, our planet was warmer that it is today with no polar ice caps present.  A study of tiny 1 mm long fossils of some of the first animals to produce a hard, shelly exoskeleton has confirmed this hypothesis.  Analysis of isotopes from the tiny shells in combination with the climate models show that at high latitudes (around 65 degrees south), sea temperatures were in excess of 20 degrees Celsius.  This might seem very warm, especially when you consider that this is an evaluation of sea temperatures at approximately 65 degrees south, today, travelling to that latitude would put you on the southernmost fringes of the Southern Ocean and close to Antarctica.  However, the data generated is similar to more recent, better understood, greenhouse climates such as that of the Late Cretaceous.

Reflected Light Microscopy – Brachiopod Fossils Used in the Study

Reflected light microscope images of Cambrian brachiopods.

Reflected light microscope images of some of the brachiopod fossils (phosphatic microfossils), used in this study.

Picture Credit: Leicester University

Co-author of the open access paper, PhD student Thomas Hearing (University of Leicester’s School of Geography, Geology and the Environment), explained:

“Because scientists cannot directly measure sea temperatures from half a billion years ago, they have to use proxy data, these are measurable quantities that respond in a predictable way to changing climate variables like temperature.  In this study, we used oxygen isotope ratios, which is a commonly used palaeothermometer.  We then used acid to extract fossils about 1 mm long from blocks of limestone from Shropshire, UK, dated to between 515 – 510 million years old.  Careful examination of these tiny fossils revealed that some of them have exceptionally well-preserved shell chemistry which has not changed since they grew on the Cambrian sea floor.” 

High Resolution Scanning Electron Microscope (SEM) Images of Brachiopod Fossils Used in the Study

SEM images of brachiopods.

Electron microscope images of some of the brachiopod fossils used in this study. Electron microscopy allows much higher resolution imaging of small structures than normal light microscopy.

Picture Credit: Leicester University

Dr Tom Harvey (University of Leicester) added:

“Many marine animals incorporate chemical traces of seawater into their shells as they grow.  That chemical signature is often lost over geological time, so it’s remarkable that we can identify it in such ancient fossils.” 

Analyses of the oxygen isotopes of these fossils suggested very warm temperatures for high latitude seas (~65 °S), probably between 20 °C to 25 °C.  To see if these were feasible sea temperatures, the researchers carried out climate model simulations for the Cambrian.  The climate model scenarios suggest that the Earth’s climate was in a “typical” greenhouse state, with temperatures similar to more recent and better understood greenhouse intervals known from the Mesozoic and the Cenozoic eras.  Ultimately, this study will help to expand our knowledge of the ecosystem that existed during the Cambrian.

The Highly Fossiliferous Comley Limestones (Shropshire, UK)

A thin section of highly fossiliferous rock of Cambrian age.

A thin section slice through the trilobite-rich Comley Limestones (Shropshire, UK).

Picture Credit: Everything Dinosaur

The curves and white wavy lines in the photograph (above), are preserved exoskeletons of numerous trilobites.

Thomas Hearing concluded:

“We hope that this approach can be used by other researchers to build up a clearer picture of ancient climates where conventional climate proxy data are not available.”

The research was carried out as an international collaboration involving scientists from the University of Leicester (UK), British Geological Survey (BGS; UK), and CEREGE (France).

Everything Dinosaur acknowledges the help of Leicester University in the compilation of this article.

3 05, 2018

The First Beak Under the Noses of Scientists

By | May 3rd, 2018|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Inspiring Ichthyornis – Top of the Pecking Order

As a very young boy, I remember eagerly striving to complete my Brooke Bond “Prehistoric Animals” card collection.  This was a set of fifty cards to collect,  given away free with packets of tea.   One of the cards featured a pair of toothed, prehistoric birds, a large, reddish coloured Hesperornis which was being mobbed by a couple of tern-like birds, this was my first introduction to Ichthyornis.  Perhaps, the first time that I realised that birds (at least primitive, toothed birds), lived alongside dinosaurs.  How wonderful to read this week that Ichthyornis, thanks to a pieced together three-dimensional skull, may be providing palaeontologists with fresh insights into avian evolution.  The Hesperornis/Ichthyornis picture card may have been burned into my conscience long ago, but it is refreshing to think that this ancient bird may represent a pivotal moment in the transition from dinosaurs to modern-day birds and its significance has only just come to light.  A team of international scientists have published a paper proposing that Ichthyornis may have had one of the first, true bird-like beaks.

The Brooke Bond Picture Card

Hesperornis and Ichthyornis

Hesperornis catching a fish, with Ichthyornis in close attention.

Picture Credit: Everything Dinosaur/Brooke Bond

Toothy Bird with the Beginnings of a Beak

Writing in the journal “Nature”, researchers report on the analysis of beautifully preserved three-dimensional Ichthyornis (I. dispar) fossil skull that is providing new evidence on the evolution of the avian head and how the skull and beaks of birds evolved from their dinosaurian ancestors.

A Three-Dimensional Image of Ichthyornis Skull Material Indicates the Tip of the Premaxillary Formed the First Beak

The tip of the premaxillary forms the first beak.

A computer generated image showing the life position of the fossil bones in the three-dimensional Ichthyornis skull.

Picture Credit: Yale Office of Public Affairs and Communications

Ichthyornis dispar

Known from fragmentary fossils from Kansas and named back in 1872 by Yale University’s Othniel Charles Marsh, it seems fitting that this new study into one of the first toothed birds described, has been led by scientists from Yale University.  Working in conjunction with colleagues from the University of Kansas, Fort Hays State University, Alabama Museum of Natural History and the McWane Science Centre (Alabama), the team report on new specimens with three-dimensional cranial remains, including one example of a complete skull and two previously overlooked cranial elements that were part of the original Yale specimen examined by Marsh.

Using CT scans and sophisticated computer modelling, individual skull and jaw bones were scanned and reproduced in three-dimensions.  This allowed a complete skull to be constructed revealing new details about the transition from dinosaur skull to a more modern bird skull.

Yale University palaeontologist and lead author of the study Bhart-Anjan Bhullar commented:

“Right under our noses this whole time was an amazing, transitional bird.  It has a modern-looking brain along with a remarkably dinosaurian jaw muscle configuration.”

Ichthyornis is part of the biota of the Western Interior Seaway, a shallow sea that split North America in two during the Late Cretaceous.  It has been regarded as an early version of a tern or gull, but its size is unknown as the few fossils found represent individuals of different sizes, however, it probably had a wingspan of no more than sixty centimetres, making Ichthyornis slightly smaller than today’s Common Tern (Sterna hirundo), a bird which fills the same ecological niche as the Mesozoic Ichthyornis.

Using the Latest Research, a New Reconstruction of Ichthyornis dispar was Produced

Ichthyornis life reconstruction.

A life reconstruction of Ichthyornis.

Picture Credit: Yale Office of Public Affairs and Communications

The Evolution of a Beak

Having built a three-dimensional model of the skull and jaw bones, the researchers were able to note that the premaxillary bone in the upper jaw had become elongated and this, working in conjunction with a keratinous tip on the lower jaw formed the first “proto-beak”.  Ichthyornis dispar shows scientists what the first type of bird beak looked like.  This beak may have evolved as the function of the hands was increasingly limited as they were adapted to form a more effective wing.  The grasping hands of the maniraptoran dinosaurs were no longer able to grasp and manipulate objects so the jaws had to take on an additional function, secondary to their main function – dispatching and consuming prey.

The Beak of Ichthyornis

The beak of Ichthyornis.

The beak of Ichthyornis evolving to replace grasping, functional hands and fingers.

Picture Credit: Yale Office of Public Affairs and Communications

Although maniraptoran dinosaurs may not have been able to pronate their hands like us and they lacked an opposable thumb, as forelimbs and hands evolved into wings, so the jaws took over the function of the digits and manus.

Bhart-Anjan Bhullar stated:

“The first beak was a horn-covered pincer tip at the end of the jaw.  The remainder of the jaw was filled with teeth.  At its origin, the beak was a precision grasping mechanism that served as a surrogate hand as the hands transformed into wings.”

The research team conducted its analysis using CT-scan technology, combined with specimens from the Yale Peabody Museum of Natural History; the Sternberg Museum of Natural History in Hays, Kansas, the Alabama Museum of Natural History; the University of Kansas Biodiversity Institute and the Black Hills Institute of Geological Research (South Dakota).

Bird Beaks versus Bird-hipped Dinosaur Beaks

The modern bird beak is a unique organ amongst vertebrates, although notably most derived Ornithischian (bird-hipped) dinosaurs possessed a beak, formed from the unique predentary bone in the lower jaw and a roughened, extension of the premaxilla (or the rostral in the case of Ceratopsians), in the upper jaw, which allowed the attachment of a keratinous tip which in conjunction formed the beak-like structure – believed to be an adaptation to assist with cropping vegetation.

This study of Ichthyornis suggests that the first bird beak was not the long organ seen in modern birds, but a little pincer tip to grasp and manipulate objects.

A Chasmosaurine Ceratopsian with the Roughened Rostral and the Predentary Forming a Plant-cropping Beak

The bones forming the beak of a horned dinosaur.

The beak of a horned dinosaur is highlighted.

Picture Credit: Rapid City Journal with additional notation by Everything Dinosaur

Fresh Insight into the Evolution of Extant Bird Skulls

The scientists conclude that their study offers new insights into how modern birds’ skulls formed.  Along with its transitional beak, Ichthyornis dispar had a brain similar to that seen in extant birds but a temporal region of the skull that was reminiscent of a dinosaur.  This suggests that during the evolution of Aves, the brain transformed first, possibly to adapt to a volant (aerial) lifestyle, whilst the remainder of the skull retained the ancestral features associated with the Dinosauria.  Ichthyornis retained a large adductor chamber bounded at the top by substantial bony remnants of the ancestral reptilian upper temporal fenestra (hole in the skull).  This combination of features indicates that important attributes of the avian brain and palate evolved before the reduction of jaw musculature and the full transformation of the beak.

The Beak of Ichthyornis Grasping a Mollusc

Holding a mollusc in its beak.

An illustration of an Ichthyornis holding a mollusc in its beak.

Picture Credit: Michael Hanson/Bhart-Anjan Bhullar

I may never have completed my Brooke Bond card collection, but at least, thanks to this new Ichthyornis study, our understanding of the evolution of the beak in birds is more complete.

26 04, 2018

Clever Cretaceous Lacewings

By | April 26th, 2018|Dinosaur and Prehistoric Animal News Stories, Main Page, Photos/Pictures of Fossils|0 Comments

Evidence of Insect Mimicry and Camouflage in Burmese Amber

Researchers from the China Agricultural University, the Nanjing Institute of Geology and Palaeontology and the Chinese Academy of Sciences, have discovered a new species of lacewing preserved in 100 million-year-old Burmese amber (burmite).  The scientists have identified two lacewing larvae that show adaptations for mimicking liverwort plants.  Mimicry and camouflage is relatively commonplace in the natural world, but evidence of this within the fossil record is extremely rare.

Two views (Dorsal and Ventral) of a Preserved Lacewing Larva Camouflaged to Look Like a Liverwort

Fossil lacewing larva preserved in amber from Myanmar. Scale bar - 1 mm.

New green lacewing larva Phyllochrysa huangi in (A) dorsal view and (B) ventral view.

Picture Credit: the Nanjing Institute of Geology and Palaeontology 

Lacewings and Liverworts

Lacewings are insects which are characterised by their very fine, reticulated wings.  They are globally widespread and something like 2,000 living species have been described to date.  As larvae and adults, they are voracious hunters and are popular with farmers and growers as they eat lots of pests, such as aphids.  Fossils of these delicate insects are rare but specimens are known that date from the Jurassic.  Liverworts are much older, they lack a vascular system and true roots tending to grow very close to the ground.  Liverworts are thought to be similar to the very first land plants that evolved in the Silurian geological period.  Despite liverworts having existed since the Palaeozoic, mimicry between insects and liverworts is extremely rare in both modern and fossil ecosystems.  This discovery, reported in the academic journal “Current Biology” represents the first record of liverwort mimicry by fossil insects and brings to light an evolutionary novelty, both in terms of morphological specialisation as well as plant-insect interaction.

Lacewing Larvae and Liverworts Preserved in Amber

Liverworts and lacewing larvae preserved in amber.

New green lacewing larva and potential model plants from Burmese amber. (B, E, G are larvae, the others are liverworts)

Picture Credit: the Nanjing Institute of Geology and Palaeontology 

Camouflaged to Look Like Liverworts

The larvae have broad flanges on their abdomen and thorax that resemble the fleshy, ribbon-like fronds of liverworts.  The insect which has been named Phyllochrysa huangi, is the only known species of lacewing with distinctive foliate lobes on the larval body.  These newly described insects are the first evidence of direct mimicry in lacewing larvae.  This camouflage may have helped the vulnerable larvae to avoid detection by predators, or they might have used this body bauplan to help ambush potential prey.

Two Phyllochrysa huangi Larvae Hide Out Amongst the Liverworts

Phyllochrysa huangi camouflaged on the liverworts (highlighted by arrows).

A life reconstruction of two Phyllochrysa huangi hiding amongst liverworts.  The larvae are highlighted by red arrows.

Picture Credit: Yang Dinghua

The researchers conclude that these fossils preserved in amber demonstrate a hitherto unknown life-history strategy amongst these types of insect, a strategy that apparently evolved from a camouflaging ancestor but did not persist into modern times with this lineage.

A Hot and Humid Cretaceous Jungle

The amber from Burma (Myanmar) has provided palaeontologists with an astonishing insight into life in a Cretaceous tropical rainforest.  Numerous types of invertebrate have been named, including damselflies, spiders and blood-sucking ticks that may have fed on the blood of dinosaurs.  The remains of larger creatures have been found preserved in amber too, including the feathered tail of a dinosaur and a baby enantiornithine bird.

To read about the blood-sucking Cretaceous parasites: Blood-sucking Dinosaur Parasites

Fossilised baby bird preserved in amber: Watch the Birdie!

Prehistoric spiders with whip-like tails: Spiders with Tails

Dinosaur tail trapped in tree resin: The Tale of a Dinosaur Tail

The globally widespread extant liverworts consist of over 9,000 named species.  Although, like the lacewings, their fossil record is very poor, it seems likely that they began to become much more diverse during the Cretaceous as the rapidly evolving angiosperm trees provided new habitats for them.  Just like their modern counterparts, Cretaceous liverworts grew on the leaves and bark of trees as well as on other plant surfaces.  It is logical to assume that the camouflaged lacewing larvae also probably lived on trees which were densely covered by liverworts, with the lacewing’s liverwort mimicry aiding their survival.

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