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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.

19 06, 2017

Volcanic Eruptions Heralded Dawn of the Dinosaurs

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

End-Triassic Mass Extinction Triggered by Volcanic Activity

The demise of the dinosaurs some sixty-six million years ago has been well documented.  This mass extinction event and its impact on the Dinosauria has been seared into the public’s consciousness with all the intensity of an asteroid impact, however, the domination of terrestrial ecosystems by dinosaurs may have been assisted by a period of intense, global volcanic activity some two hundred million years ago.

Much of the Diverse Terrestrial Fauna of the Late Triassic Died Out

The diverse fauna of Triassic Argentina.

Diverse fauna of north-western Argentina in the Triassic.

Picture Credit: Victor Leshyk

A team of researchers based at British universities have found that huge pulses of volcanic activity are likely to have played a major role in triggering the end-Triassic mass extinction event.  The early dinosaurs survived and with a lot of the competition removed, the scene was set for the domination of life on land by this Order of reptiles.

Scientists from the University of Exeter in collaboration with colleagues from Southampton University and the Department of Earth Science at the University of Oxford have published a paper that looks at the world-wide impact of immense gas emissions as a result of volcanism and their link to the end-Triassic extinction event.

Life on Earth at the End of the Triassic

Some fifty million years or so, after the “Great Dying” – the end-Permian extinction event that saw the demise of some 95% of all life on our planet, the end-Triassic extinction event led to wholesale changes in global ecosystems.  Numerous food webs on land and in the sea collapsed and many different types of animals and plants were affected.

The Landscape of the Triassic

Triassic landscape.

Ecosystems that had recovered from the end-Permian extinction event were to be devastated once again at the end of the Triassic.

Major Casualties of the end-Triassic Extinction Event

  • Marine molluscs (especially gastropods and cephalopods)
  • Brachiopods
  • Bivalves
  • Marine sponges
  • Conodonts
  • Marine vertebrates – fish and many types of marine reptiles (a number of Ichthyosaur genera along with the extinction of the Placodonts and the Nothosauroidea)
  • Several families of Archosaurs along with mammal-like reptiles and numerous types of amphibians
  • Large numbers of plants especially within the Lycopodiopsida (club mosses) and the Sphenopsida (horse tails)

Writing in the academic journal “The Proceedings of the National Academy of Sciences of the United States of America”, the researchers conclude that huge volumes of volcanic gas had a dramatic effect on life on Earth and slowed the recovery of ecosystems afterwards.

A Large and Abrupt Release of Carbon Dioxide

Following the discovery of volcanic rocks of approximately the same age as the extinction event, huge amounts of volcanic carbon dioxide (CO2) emitted into the atmosphere had previously been suggested as an important contributor to this mass extinction event.  Previous studies had also shown that this intense volcanism might have occurred in phases, over tens of thousands of years, but the global extent and potential impact of these volcanic episodes had remained unknown.  Extensive areas of flood basalt, a consequence of the volcanic activity, built up across much of the super-continent of Pangaea, these basalts are now found on four continents, a consequence of plate tectonics and the break-up of Pangaea.  These deposits are known as the Central Atlantic Magmatic Province (CAMP).

By studying the level of mercury found within sedimentary rocks formed during the extinction phase, the scientists were able to reveal clear links in the timing of the CAMP formation and the end-Triassic extinction.  The intense volcanic activity released mercury into the environment, which spread across the planet, before being locked away in sediments.  Any rocks formed during extensive volcanism would therefore have a higher than normal mercury content.

The research team studied sedimentary deposits from six locations (Austria, Argentina, Canada, Greenland, Morocco and the UK).  The levels of mercury were analysed and five of the six records showed a sizeable increase in the mercury content at the beginning of the end-Triassic extinction horizon.  Other peaks were observed between the start of the extinction event and the Triassic-Jurassic boundary, which occurred around 200,000 years later.

The Researchers Studied Sedimentary Deposits from Morocco

Late Triassic sediments (Morocco).

Late Triassic sediments (Morocco) were part of the mercury study.

Picture Credit: Jessica Whiteside

The higher levels of mercury coincided with previously established increases in atmospheric CO2 levels.  The volcanism would have produced vast amounts of carbon dioxide that would have affected the gaseous content of the atmosphere and led to periods of global warming.

One of the authors of the scientific paper, geologist Professor Stephen Hesselbo (Camborne School of Mines at Exeter University) commented:

“This volcanic activity is strongly believed to have led to one of the largest extinction events in the Earth’s history which, in turn, paved the way for the era of the dinosaurs.  By studying the sediment deposits in Europe, South America, North America and Africa, we have been able to show a large increase in levels of mercury, which shows a clear link between this volcanic activity – specifically from very large lava flows – and the mass extinction in the era.  It’s a fascinating discovery that paves the way to enhance our understanding of this and other significant climate change events.”

In a press release, lead author Lawrence Percival, a geochemistry graduate student at Oxford University stated:

“These results strongly support repeated episodes of volcanic activity at the end of the Triassic, with the onset of volcanism during the end-Triassic extinction.  This research greatly strengthens the link between the Triassic mass extinction and volcanic emissions of CO2.  This, further evidence of episodic emissions of volcanic CO2 as the likely driver of the extinction, enhances our understanding of this event, and potentially of other climate change episodes in Earth’s history.”

To read a related article on the rise of the Dinosauria: Extreme Equatorial Climates Slowed the Rise of the Dinosaurs

17 06, 2017

Theropod Tracks and Ornithopod Tracks

By | June 17th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Distinguishing Theropod tracks from Ornithopod Tracks

Recently, Everything Dinosaur posted an article about a new study of the Dinosaur Stampede National Monument (Queensland, Australia), in which a three-dimensional Australovenator foot was used to assess what type of dinosaur was responsible for producing a set of eleven, large, three-toed footprints.  In this innovative research, conducted by scientists from the Australian Age of Dinosaurs Museum of Natural History and the University of Newcastle (New South Wales), it was concluded that the tracks could have been made by a meat-eating dinosaur.  Previous research had challenged the interpretation that the trace fossil site preserves evidence of a dinosaur stampede as a substantial group of smaller plant-eating dinosaurs evaded an attack from a big Theropod.

Other interpretations of the Dinosaur Stampede National Monument have suggested that the hundreds of tracks preserved at this location, some seventy miles south of the town of Winton in Queensland, do not represent evidence of a large, meat-eating dinosaur attacking a flock of smaller dinosaurs.  Some scientists have contradicted this analysis and proposed that the bigger, tridactyl tracks were made by a big Ornithopod, a herbivorous dinosaur, something like a Muttaburrasaurus.

Could the Larger Tracks at the Dinosaur Stampede National Monument have been made by a Herbivore?

Lark Quarry Ornithopod

The plant-eater wandering across the Lark Quarry environment

Picture Credit: Anthony Romilio, The University of Queensland

The Confusion Between Bipedal Plant-eaters and Bipedal Meat-eaters

Having published our article, we were then emailed and asked to explain how it was possible to confuse the footprints of a large bipedal, herbivorous dinosaur with those of an equally sized carnivorous dinosaur.  So, here are some pointers about the differences between the types of tracks, plus an explanation as to why it can be so hard to pin down which type of bipedal dinosaur left prints and tracks.

For those scientists that study dinosaur footprints, being able to distinguish the prints from a meat-eating Theropod from those of a large, herbivorous Ornithopod is a challenging task.  If the prints are ideally preserved with lots of detail, identification can be relatively straight-forward, if the body fossils of a dinosaur could be found close by, then there would be further evidence to support a diagnosis, but sadly, discovering exquisitely preserved dinosaur tracks – these are very rare events indeed!

An Exquisitely Preserved Dinosaur Track Assigned to the Ichnogenus Eubrontes

A three-toed dinosaur footprint from India.

The tridactyl print can be clearly made out, it has been assigned to the ichnogenus Eubrontes.

An Identification Guide

The track made by a Theropod dinosaur (the pes of a meat-eating dinosaur), if perfectly preserved, should show sizeable claw marks on the end of the toes.  The toes themselves should look quite slender and in general terms the print should look longer than it is wide.  The length of the foot when compared to the width should give the track a characteristic “v shape”.

The well-preserved track of a large Ornithopod, a plant-eater should lack distinctive claw marks.  The ends of the toes should be more blunt and rounded in appearance.  The toes tend to be quite wide and the foot proportions are different.  For example, the foot may be much wider.  The wider pes as a proportion of overall foot length gives the track a “u shape”.

Ornithopod versus Theropod Footprint – Identification Guide

Comparing different types of dinosaur footprint.

Theropod print compared to an Ornithopod print.

Picture Credit: Everything Dinosaur

Identifying the Dinosaur from the Footprint – Problems

The fact that something so ephemeral as a single track or a trackway can survive for millions of years is remarkable.  However, over time these trace fossils can become distorted making identification extremely difficult.  Features, once very striking are easily masked by the effect of weathering and erosion.  Any repairs undertaken or attempts to preserve the prints could also lead to the loss of definition, causing further problems when it comes to making an assessment as to what type of animal produced the tracks.  Unauthorised attempts to make casts could also result in considerable damage to the track(s) thus further hampering identification.

It does not matter, whether the track represents a natural cast (created by sediments filling in a track), or whether it is a true track (the impression preserved in the ground made by the foot itself), determining what type of creature made the prints is an extremely difficult process.  Some of the most difficult tracks to interpret of all are undertracks.  An undertrack is formed below the sediment as surface material is compressed downwards as the organism moved across the area.  These undertracks lack many types of marks made only at the surface, scratches, scuffs, clear claw impressions or any evidence of a tail drag.

The thousands of dinosaur tracks at the Lark Quarry site (Dinosaur Stampede National Monument), are truly a remarkable record of the behaviour and activity of a group of dinosaurs.  What exactly those tracks represent is open to different interpretations – but that’s science for you.

Further articles on the Lark Quarry dinosaur tracks:

Could Australovenator have made some of the tracks at Lark Quarry?: Lark Quarry Dinosaur Footprints – Scientists Re-examine the Evidence

Lark Quarry Tracks Re-examined: A New Interpretation of the Lark Quarry Fossils

16 06, 2017

Australovenator Steps into Lark Quarry Dinosaur Debate

By | June 16th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Scientists Reconstruct Dinosaur Foot to Help Interpret Tracksite

The famous dinosaur tracks at Lark Quarry, (Dinosaur Stampede National Monument), near the town of Winton (Queensland, Australia),  have been the subject of research for decades.  Unlike dinosaur bones and teeth that can be transported a huge distance from the place where the dinosaur died, footprints and tracks preserve evidence of activity and behaviour.  The majority of trace fossils provide direct, in situ evidence of the environment at the time and location where the animal was living.

Lark Quarry Dinosaur Tracks

Lark Quarry Dinosaur Tracks

Examples of Lark Quarry dinosaur footprints.

Picture Credit: Dr Steve Salisbury

Different Interpretations of the Dinosaur Tracks

At Everything Dinosaur, we think the first, formal attempt to interpret the numerous dinosaur tracks preserved in the finely grained sandstone at the Lark Quarry site took place in 1984.  Eleven, large, three-toed prints were interpreted as having been made by a big meat-eating dinosaur that had lunged at a flock of small Ornithopods that it had cornered.  The tracks were interpreted as a “dinosaur stampede” as the smaller plant-eating dinosaurs panicked and tried to avoid the jaws of a ten-metre-long Theropod.  The ichno genus (a name given to an animal known only from trace fossils), Tyrannosauropus was erected.  Over the years, a number of other interpretations have been put forward, including the hypothesis that the big tri-dactyl prints don’t represent a predator but were made by a large Ornithopod, something akin to a Muttaburrasaurus.  Other interpretations of this famous fossil site include that the tracks were made by dinosaurs as they swam and waded across a body of water.

Swimming Dinosaurs Hypothesis: Dinosaurs Not Stampeding but Swimming

No Tyrannosauropus at Lark Quarry After All: Lark Quarry Tracks Made by a Big Plant-Eating Dinosaur

Dinosaur Foot Reconstruction – A New Analysis of the Tracks

Distinguishing between the three-toed prints of meat-eating dinosaurs and those of similar sized plant-eaters, which also walked on three toes is a tricky business.  However, in an innovative piece of research, a team of scientists from from the University of Newcastle (New South Wales) and the Australian Age of Dinosaurs Museum of Natural History in Winton, set about reconstructing the foot of an Australian Theropod dinosaur Australovenator wintonensis in a bid to reproduce the tracks in similar sediment, which could then be compared to the fossil trackway.

Reconstructing the Foot of Australovenator

Foot model helping to interpret Lark Quarry tracks.

Reconstructing the left foot of Australovenator.

Picture Credit: PeerJ

The picture above shows (A) calculating the claw length of Australovenator and (B-D) the four claws associated with the left foot of the dinosaur with reconstructed sheaths.  The bones of the foot have been reconstructed (F) and using Emu feet for an anatomical comparison, (G) shows the foot reconstructed with tendons added, whilst (H) is the skin covered biologically restored foot (left pes) of Australovenator.

Australovenator wintonensis

A three-dimensional foot of Australovenator was created as fossils of this Megaraptoran Theropod are known from similar aged strata as the Lark Quarry tracks.  In addition, Australovenator is the only meat-eating dinosaur from Australia which has had its foot bones discovered.  The researchers used a variety of substrates to test the prints, scuff marks and scratches made by the large dinosaur and they concluded that their recreated impressions were reminiscent of the trace fossils.  This suggests that the eleven, large, three-toed tracks at Lake Quarry (now known as the Dinosaur Stampede National Monument), could have been made by an Australovenator-like carnivorous dinosaur.

An Illustration of Australovenator wintonensis Crossing the Lark Quarry Sediments

Australovenator footprint study.

Australovenator making tracks.

Picture Credit: Travis R. Tischler

The CollectA Australovenator Dinosaur Model

Australovenator was a member of the Allosauria clade of Theropod dinosaurs.  Fossils of this six-metre-long carnivore were discovered in 2006.  Although the fossil material was far from complete, the Australovenator genus was formally erected by Australian palaeontologist Scott Hucknull in 2009.  CollectA introduced a model of Australovenator just three years after the scientific description.  Models of Megaraptoran Theropods are quite rare, it is great to see that CollectA have added an Australovenator replica to their “Prehistoric Life” model range.

The CollectA Australovenator Dinosaur Model

The CollectA Australovenator dinosaur model.

The CollectA Australovenator replica.

Picture Credit: Everything Dinosaur

To view the full range of CollectA dinosaur and prehistoric animal models: CollectA Prehistoric Life Models

15 06, 2017

Curious African Cynodont Turns up in Brazil

By | June 15th, 2017|Dinosaur and Prehistoric Animal News Stories, Main Page, Photos/Pictures of Fossils|0 Comments

Aleodon from Africa Present in Brazilian Triassic Rocks

A team of international researchers have reported the discovery of fossils attributed to the African cynodont Aleodon in Middle-early Late Triassic rocks from several locations in the state of Rio Grande do Sul (southern Brazil).  Prior to these fossil finds, this protomammal (a member of the Probainognathidae family), a distant ancestor of modern mammals, was only known from Africa.

A Scale Drawing of the Skeleton of Aleodon (A. cromptoni)

Aleodon scale drawing.

The known bones of Aleodon are shown in yellow.

Picture Credit: PLOS ONE

In the picture above the known bones attributed to Aleodon (A. cromptoni) are shown in yellow and a cat provides a scale comparison.

Living Alongside Dinosaur Precursors

Writing in the on-line academic journal “PLOS ONE”, the researchers, which include Agustín Martinelli (Universidade Federal of Rio Grande do Sul, Brazil), conclude that fossils previously thought to represent another cynodont – Chiniquodon actually are Aleodon specimens, as such they are the first of this genus to be found outside of Africa.  The carnivorous Aleodon lived alongside basal members of the Dinosauria and other types of archosaur, as well as numerous mammal-like reptiles, including the giant herbivore Dinodontosaurus.  The fossils of Dinodontosaurus are so numerous that they are used to date the relative age of the strata in this part of southern Brazil.  All the fossils ascribed to Aleodon, including cranial material and teeth come from the Dinodontosaurus Assemblage Zone.

Aleodon Skull Material and Line Drawing (Aleodon cromptoni)

Aleodon skull and line drawing.

Skull in left lateral view with accompanying line drawing. Scale bar = 50 mm.

Picture Credit: PLOS ONE

Namibian and Tanzanian Fossils

The Aleodon genus was first erected based on fossil material discovered in Tanzania and Namibia.  The South American material was compared to the African specimens and a new species of Aleodon, a sister taxon to the African species was named.  The new Aleodon species honours Dr Alfred “Fuzz” Crompton, who established the genus in 1955 with the naming of A. brachyrhamphus.

In a reassessment of the African fossil material, a specimen form Namibia which was thought to represent a member of the related family, the Chiniquodontidae or possibly a member of the Traversodontidae may actually be an Aleodon.  The scientists also identified as Aleodon a total of seven specimens from the Rio Grande do Sul region.  Phylogenetic analysis indicated that Aleodon cromptoni may be, as suspected, a species in the Chiniquodontidae family.

Whilst the research work was hampered due to the incomplete and partial specimens, the authors note that the identification of these Late Triassic Aleodon fossils in Brazil strengthens the correlation between probainognathians from this epoch in South America and in Africa.

Part of the Upper Jaw of A. cromptoni with Line Drawing

Upper jaw fossil material (Aleodon cromptoni).

Photographs and accompanying drawings of right maxilla MPDC-501-117 in lateral (A), ventral (B), and medial views (C). Scale bar equals 10 mm

Picture Credit: PLOS ONE

13 06, 2017

Watch the Birdie (Enantiornithine in Amber)

By | June 13th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles|0 Comments

Nearly Complete Baby Bird Preserved in Amber

Researchers from the Chinese Academy of Sciences in collaboration with colleagues from the Royal Saskatchewan Museum (Canada) and the China University of Geosciences have announced the discovery of yet another prehistoric animal preserved entombed within a 99-million-year-old piece of amber from Myanmar.  The animal is a baby bird, perhaps only a few days old when it was engulfed in sticky tree resin back in the Cretaceous.  It is an astonishing discovery, one of a number of remarkable fossil finds made in recent years from the amber deposits of northern Myanmar.  Most of the skull and neck is preserved along with part of a wing, a hindlimb, complete with claws and some soft tissue surrounding the tail.  Some of the plumage has also been encased within the amber nodule.  Described as representing a specimen of the Enantiornithes clade, it is the most complete bird preserved in amber found to date.

Enantiornithine Hatchling Preserved in Burmese Amber

Baby Enantiornithine bird trapped in amber.

Baby bird preserved in amber.

Picture Credit: Ryan McKellar (Royal Saskatchewan Museum) et al.

The picture above shows the amber nodule (a).  The nodule measures approximately 86 mm × 30 mm × 57 mm it has been assigned the specimen number HPG-15-1 and it has been cut in half.  The cut-mark is represented in (c) which shows the cut as a dotted line against a line drawing of the bird’s remains preserved in the nodule.  An interpretation of the high-resolution scans showing the skeletal components is shown in (b).  The disarticulated remains of this individual has led the research team to speculate that the corpse of this young bird might have been scavenged prior to its entombing in the tree resin.

A Very Young Bird

Writing in the academic journal “Gondwana Research”, the scientists conclude that the shape of the skeleton and the plumage indicates a very young bird, the well-developed wings, claws and the presence of some filamentous body feathers suggests that Enantiornithines were hatched in a relatively advanced state, being perhaps able to feed itself almost immediately.  Being born nearly fully developed and independent of the parents is termed precocial.  Many modern birds are precocial, examples include ostrich chicks and ducklings.  These birds are able to keep themselves warm and move about, often leaving the nest in just a few hours.  The scarcity of body feathers on the Cretaceous bird represents a distinct departure from the feather coverings found in today’s precocial birds.  Perhaps the Enantiornithines relied on their parents to brood them to keep them warm, or perhaps these birds hatched during the hottest part of the year, when insulation was not as necessary.

A Three-Dimensional Model Created from the High-Resolution Scans

Fossil bird trapped in amber.

Using 3-D scans the researchers were able to create a model of the death pose of the bird.

Picture Credit: Ryan McKellar (Royal Saskatchewan Museum)

Commenting on the importance of this fossil discovery, Ryan McKellar (Royal Saskatchewan Museum) stated:

“We’ve had more complete specimens, where you get more of the skeleton preserved, from compression fossils, but never with this level of detail.  It’s like a little diorama.”

Nicknamed “Belone”

The amber nodule also contains insect remains, plant material and mites, providing an insight into the fauna and flora of a conifer forest that existed around 99 to 100 million years ago.  The amber was found by a miner back in 2014, at first the claw was thought to have come from a lizard but once the piece had been purchased by the Hupoge Amber Museum in Tengchong City, China, a correct identification was made.  The specimen was nicknamed “Belone” a local term for an amber-coloured bird called the Oriental skylark.

Researchers including palaeontologist Lida Xing (China University of Geosciences), used CT scans to examine fossil elements hidden from view.  These scans revealed the skull and part of the spine, although the cutting of the nodule damaged the anterior portion of the head and the tiny jaws.

As for its feathers, the bird had different kinds: some that palaeontologists have seen on dinosaurs, but others that are closer to modern-day birds.  This, the research team commented, was one of the most surprising and rewarding finds.

The Enantiornithine Hind Leg

Enantiornithine hindlimb

A closer view of the hind limb of the Enantiornithine bird.

Picture Credit: Ming Bai

A Precocial Bird

The presence of strong toes equipped with sharp claws suggests that this bird could clamber around in the trees shortly after hatching, yet more evidence of just how independent this young bird was.  Precociality is thought to be ancestral in birds.  Thus, altricial birds tend to be found in the most derived families within the Aves (birds) Order.   There is some evidence for precociality in the Dinosauria.  It seems that being independent at birth is a characteristic that is basal to the birds.

A Close View of One of the Claws

Enantiornithine claw.

A close view of the claw, even individual scales have been preserved in the amber.

Picture Credit: Ming Bai

The amber mines of Kachin Province (northern Myanmar) are renowned for their remarkable fossils, back in 2016, Everything Dinosaur wrote an article about the remnants of a bird’s wing that had been preserved trapped in amber.

To read more: Bird Wing Trapped In Amber

Later that year, Everything Dinosaur reported on discovery of a fragment of a dinosaur’s tail that had been found preserved inside amber.  That remarkable specimen was studied by a number of the researchers who contributed to the study of this baby bird fossil.

To read more about the dinosaur tail discovery: The Tale of a Dinosaur Tail

The scientific paper: “A mid-Cretaceous Enantiornithine (Aves) Hatchling Preserved in Burmese Amber with Unusual Plumage” by Lida Xing, Jingmai K. O’Connor, Ryan C. McKellar, Luis M. Chiappe, Kuowei Tseng, Gang Li, Ming Bai published in Gondwana Research.

12 06, 2017

Dinosaurs of China – Exhibits Arrive

By | June 12th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Chinese Takeaway Delivered Safe and Sound

The amazing dinosaur exhibits that form this summer’s world exclusive Dinosaurs of China exhibition have arrived safe and sound at their Nottinghamshire venues.  This exciting exhibition, which features a number of specimens that have not been seen outside of Asia before, opens on Saturday, July 1st and the dedicated staff at Wollaton Hall and the Nottingham Lakeside Arts Centre with the collaboration of technicians from the Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing, have just three weeks to put all the exhibits together.

Unloading Giant Dinosaur Vertebrae

Unloading an exhibit (Dinosaurs of China).

Vertebrae from the giant Mamenchisaurus exhibit are carefully unloaded.

Picture Credit: Dinosaurs of China

Jumbo-Sized Jigsaw Puzzles

Before the exhibits can tell the fascinating story of how the dinosaurs evolved into birds, all the individual parts of the various dinosaurs have to be put together.  This is no mean feat, as Wollaton Hall will be home to a massive Mamenchisaurus dinosaur skeleton for the next five months.  The neck of Mamenchisaurus is a fraction under ten metres in length and it contains nineteen giant bones (cervical vertebrae).  The finished Mamenchisaurus exhibit will stand the same height as three double decker buses!

Unloading a Dinosaur at Wollaton Hall

Workmen unloading dinosaur dorsals.

The people unloading the exhibits provide a handy scale for the Mamenchisaurus specimen.

Picture Credit: Dinosaurs of China

After a fifty-day, five-thousand-mile trip from China to the UK, this is one Chinese takeaway that will take a lot of careful handling.

The main exhibition at Wollaton Hall will feature twenty-six prehistoric animal skeletons and fossils that include some of the best-preserved specimens in the world.  Dr Adam Smith, Exhibition Curator, commented:

“It’s absolutely incredible to have the Dinosaurs of China here, having completed their two-month long, inter-continental journey.  Seeing such important finds up close is really thrilling and we can’t wait to start the installation process so we can share them with the rest of the country this summer!”

Dr Adam Smith Checks Over a Specimen

Checking over an exhibit.

Counting the bones – all present and correct.

Picture Credit: Dinosaurs of China

Visitors to the complementary exhibition at Nottingham Lakeside Arts will be greeted by two fascinating dinosaur skeletons – the Alxasaurus, which when it was alive, was probably covered in a coat of shaggy feathers and the fearsome Early Jurassic Dilophosaurus.   Dilophosaurus has two, thin, bony crests that ran from the top of its nose to the back of its head, hence this dinosaur’s name which means “double-crested lizard”.

Dilophosaurus “Double Crested Lizard”

Dilophosaurus dinosaur model.

Wild Safari Prehistoric World Dilophosaurus.

Picture Credit: Everything Dinosaur

The Dilophosaurus Puzzle

The Dilophosaurus fossils found in China, may not be Dilophosaurus at all!  Some palaeontologists think that these fossils belong to a different, but related dinosaur called Sinosaurus (Sinosaurus triassicus).  That’s the great thing about palaeontology, new theories about these long extinct creatures are being put forward all the time, as more fossils are found.

A spokesperson from Everything Dinosaur explained:

“We are finding out new things about dinosaurs all the time!  That’s why this exhibition is so very special as it will give visitors the chance to learn about some of the most important dinosaur discoveries ever made.”

Preparing for the Dinosaur Exhibits

Preparing for the dinosaur exhibit.

Preparing a steel frame to help support a dinosaur exhibit.

Picture Credit: Dinosaurs of China

Lots of Family-Friendly Activities

Nottingham Lakeside Arts have lots of exciting family-friendly activities planned including an interactive exhibition that will explore how palaeo-art and science helps palaeontologists to work out what dinosaurs looked like.  Check out Nottingham University’s Life Science collection that will also be on display.

There will also be plenty of exciting activities and workshops to keep families entertained at Wollaton Hall too.  A free “Dino Explorer Zone” is being installed to provide families with a range of themed activities and puzzles.

All in all, there’s enough going on to make every young dinosaur fan roar with excitement and for the mums, dads, grandparents and guardians, you can expect to learn something new about these amazing prehistoric monsters.

Tickets for the exhibition are now on sale.  Prices are £7.70 for an adult and £5.50 for a child.  Family tickets are £22 for two adults and two children.  Children under five go free, so there really is no excuse – catch up with the dinosaurs from July 1st until October 29th!

For more information, please visit Dinosaurs of China Exhibition

9 06, 2017

The Mystery of the Cleveland-Lloyd Dinosaur Quarry

By | June 9th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Has the Cleveland-Lloyd Dinosaur Quarry Mystery Been Solved?

One of the most prolific dinosaur fossil sites to be found anywhere in the world lies thirty miles to the south of the town of Price in Utah.  The site is close to the small community of Cleveland (Emery County) and some 15,000 dinosaur bones have been collected from this site to date.  The strata represent Upper Jurassic siltstone (Brushy Basin member of the Morrison Formation) and this location is the densest collection of Jurassic dinosaur fossils known to science.

Since the first excavations were carried out in the late 1920’s, palaeontologists have been puzzled by the assemblage of vertebrate fossils they found.  Although, carnivorous dinosaurs were probably less common in the palaeoenvironment than the plant-eaters, at this site, the fossils of Theropods (carnivores) outnumbers the fossils of herbivorous dinosaurs by almost three to one.  In addition, the most common dinosaur fossil material is Allosaurus, the bones of this large dinosaur are extremely numerous at least forty-six individuals (based on femur bone counts) are recorded.

A Mounted Skeleton of the Late Jurassic Carnivore Allosaurus

An Allosaurus skeleton.

Allosaurus fossils dominate the Cleveland-Lloyd quarry fossil assemblage.

Picture Credit: Everything Dinosaur

For nearly one hundred years, palaeontologists have puzzled over this unique fossil assemblage.  Why is this particular location so full of the bones of carnivorous dinosaurs?  Why are the vast majority of these bones from a single genus – Allosaurus?

A Pie Chart Showing the Proportion of Different Dinosaur Fossils from the Cleveland-Lloyd Quarry

Cleveland-Lloyd fossil assemblage.

A pie chart showing the proportion of dinosaur fossils by genus.

Picture Credit: PeerJ with additional annotation by Everything Dinosaur

The pie chart above lists dinosaur fauna plus one turtle (Glyptops) and a crocodyliform (Goniopholis) from the Cleveland-Lloyd Dinosaur Quarry.  The bone symbol identifies meat-eating dinosaurs and the fir tree, plant-eating dinosaurs.  The fossils of Allosaurus dominate the bonebed.

Theories Explaining the Cleveland-Lloyd Dinosaur Quarry Bonebed

Several theories have been suggested as to what caused the build-up of dinosaur fossils at this location and why the majority of them represent one carnivorous genus.

  • This was a predator trap.  A pond attracted dinosaurs to the site as it was a source of water in the dry season.  These animals got stuck in the mud and they died, this in turn attracted scavengers who also become stuck and perished.
  • This site could mark a mass death assemblage of a lot of dinosaurs which died in a drought.
  • Was the water source toxic and this poisoned a lot of dinosaurs?  The rotting corpses attracted scavengers and these too were poisoned.

Writing in the academic journal “PeerJ” a team of researchers have put forward a new theory to explain the unusual taphonomy (the process of fossilisation).  The use of modern data techniques suggests that the quarry represents a series of catastrophic events that occurred at the same place over time, rather than a single mass death assemblage.

The research team, which included lead author Joseph Peterson (University of Wisconsin-Oshkosh), conclude that the myriad of small bone fragments found at the site, were created during periods of drought as bones which were not buried were weathered and eroded away on the surface.  Dinosaur carcasses were washed into the site which represented a temporary (seasonal or ephemeral pond) during frequent flood events.  As the corpses decayed, they led to very high levels of minerals and organic material in the water (hypereutrophic conditions).  This discouraged scavenging (which explains the lack of gnaw marks and other evidence of scavenging by predators at the site).  As more flood events took place, so more corpses were washed into the area and the existing skeletons were re-deposited.  Hence the jumble of bones.  The hypereutrophic water created an environment in which fish, turtles and crocodiles could survive and carnivorous dinosaurs were dissuaded from eating the carcasses.  Only a handful of crocodyliform teeth have been found at the Cleveland-Lloyd site, along with some turtle shell fragments, whereas, elsewhere in the Morrison Formation, turtle and crocodyliform teeth are much more numerous.

Explaining the Unusual Bonebed at the Cleveland-Lloyd Quarry Site

How did the Cleveland-Lloyd fossil site form?

Explaining how the Cleveland-Lloyd fossil site came into being.

Picture Credit: PeerJ

The image above reflects the newly proposed theory as to how the Cleveland-Lloyd Dinosaur Quarry formed.

(A) A flood causes the carcasses of dinosaurs to be deposited in the quarry area.  High levels of organic matter decaying leads to hypereutrophy (an excess of minerals in the water source).  This discourages predators from scavenging and deters freshwater fauna such as fish, turtles and crocodile-like creatures.

(B) As water levels fall during the dry season, bones that were not buried during the flood stage remain exposed on the surface.

(C) In arid conditions the surface bones are subjected to weathering and erosion.

(D) A subsequent flood event leads to more carcasses being incorporated and the reworking of existing bones within the deposit.

The scientists conclude that this cycle was repeated until the deposit maintained a higher water table, producing the limestone layers above the bone-bearing silts and muds.

A Model of the Fearsome Late Jurassic Predator Allosaurus (A. fragilis)

Schleich dinosaur model (Allosaurus).

The new for 2017 Schleich Allosaurus dinosaur model.

Picture Credit: Everything Dinosaur

8 06, 2017

Megalosaurus Fossil Still Surprises

By | June 8th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

World’s First Named Dinosaur Reveals New Teeth

The fossils that led to the first scientific account of a dinosaur can still provide some surprises, even 193 years after the original paper describing them was published.  The first dinosaur to be scientifically described Megalosaurus (M. bucklandii), has stepped once more into the spotlight.  A team of researchers have discovered five new teeth within the lower jaw fossil of the world’s first named dinosaur.

Megalosaurus Fossils Used to Describe the First Dinosaur in 1824

Megalosaurus teeth and jaws.

Views of the dentary (lower jaw) and individual teeth (lectotype Megalosaurus).

Picture Credit: Everything Dinosaur

The picture above shows the original lithograph of the right dentary of Megalosaurus.  The jawbone is show in lingual* view (top) and in buccal** view (middle) with drawings of individual teeth (bottom).

Using state-of-the-art computer tomography scanning technology and three-dimensional computer generated modelling software, the researchers from the Warwick Manufacturing Group (WMG), an academic department at the University of Warwick, in collaboration with scientists from the University of Oxford’s Museum of Natural History have been able to provide new insights about one of the most iconic fossils in the world.

One of the authors of the study, presented this week at the Institute of Electrical and Electronics Engineers (IEEE)’s conference in Italy, Professor Mark Williams stated:

“Being able to use state-of-the-art technology, normally reserved for aerospace and automotive engineering, to scan such a rare and iconic natural history specimen was a fantastic opportunity.  When I was growing up I was fascinated with dinosaurs and clearly remember seeing pictures of the Megalosaurus jaw in books that I read.  Having access to and scanning the real thing was an incredible experience.”

Famous Dinosaur Jawbone

In 1824, the Reverend William Buckland published a description of various fossils that had been found as quarrying tunnels were excavated at Stonesfield, north of Witney in Oxfordshire.  The fossils had been found some years before, the dentary having been placed in the collection of the Oxford Anatomy School at Christchurch College (Oxford) in 1797.  Reverend Buckland believed the fossilised bones and teeth came from a giant, antediluvian lizard, hence the name “Big Lizard”, Megalosaurus having been proposed by James Parkinson in 1822.

A 19th Century Interpretation of Megalosaurus Compared to a Modern Interpretation of M. bucklandii

The changing view of Megalosaurus.

A modern interpretation of Megalosaurus (left) with a reconstruction based on the original illustration by Richard Owen (right).

Picture Credit: University of Warwick/Mark Garlick

The illustration above shows an artist’s impression of how Victorian palaeontologists such as Richard Owen thought the Megalosaurus looked (right), compared with a modern interpretation of this Middle Jurassic carnivore.

Digital Three-Dimensional Image of the Dentary

Using state of the art CT scanning technology and specialist three-dimensional analysis software, Professor Williams took more than 3,000 X-ray images of the world-famous Megalosaurus jawbone, creating a digital three-dimensional computer generated image.  The image revealed five previously unseen teeth embedded in the dentary and also provided important insights into historical repairs.  It turns out that there is actually less plaster and filler in the fossil, as this technique has allowed scientists to see the extent of the infilling and repairs for the first time.

Megalosaurus bucklandii was Probably an Apex Predator

The Megalosaurus model (Oxford Museum)

Dinosaur in the Garden (Megalosaurus)

Picture Credit: Everything Dinosaur

The specimen is damaged, it is likely that some of the damage occurred when the fossil was excavated but over the two hundred years since the fossil was found some restoration work has taken place.  For example, records at the Oxford University Museum of Natural History, where the specimen is housed, show that sometime between 1927 and 1931 repairs to the jawbone took place.  The scans show the true extent of repairs on the fossil for the first time, revealing that there may have been at least two phases of repair, using different types of plaster.  This new information will help the museum make important decisions about any future restoration work on this iconic fossil.

The analysis also revealed the presence of five teeth that had not been detected before.  The teeth consist of the remains of old, worn and broken teeth plus embryonic replacement teeth.  Unlike us, Megalosaurus was able to continually replace its teeth throughout its life.  The replacement tooth grew inside the jaw, adjacent to the root of the active tooth on the lingual* side of the jaw.  A full-sized, but very thin crown formed first and this grew in thickness as more layers of dentine were added.  The growth of the embryonic tooth placed pressure on the active tooth root, causing the root to become slowly reabsorbed into the jawbone.  The replacement tooth was able to push itself inside the old tooth root and effectively usurp that tooth from the socket in the jaw where it had been located.  The old, worn tooth having been weakened, would most likely break and the crown would be lost, permitting the younger tooth to replace it in the jawline.  A similar process is seen in extant Crocodylia today.

Helping to Identify Forgeries

This research was made possible through a collaboration between Professor Williams’ research group at WMG, University of Warwick – including PhD researcher Paul Wilson – and Professor Paul Smith, director of the Oxford University Museum of Natural History.   When not being scanned or used in other research, the Megalosaurus jawbone forms part of an extensive British dinosaur fossil display at the Oxford University Museum of Natural History.

An ability to utilise a non-invasive technique to map fossil material provides palaeontologists and conservators with vital information about the preservation status of a specimen.  It also identifies and maps any repairs that have taken place previously.  In addition, this technique which does not harm the fossil, can detect the presence of filler and other modifications often added by unscrupulous dealers to raise the potential value of their fossil finds.

Forgeries and hoaxes have no hiding place when it comes to CT scans.

The research was recently presented at the Institute of Electrical and Electronics Engineers (IEEE)’s International Instrumentation and Measurement Technology Conference in Torino, Italy.

The scientific paper, “Utilising X-Ray Computed Tomography for Heritage Conservation: The case of Megalosaurus bucklandii”

* lingual view = a view of the side of the jaw that is adjacent to the tongue.

** buccal view = a view of the side of the jaw that is adjacent to the cheek.

7 06, 2017

T. rex Sheds Its Feathers?

By | June 7th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|2 Comments

The Scaly Skin of Tyrannosauroids

So, it is published!  A team of eminent scientists, some of the leading lights in palaeontology, have published in the Royal Society Biology Letters details of research that questions whether Late Cretaceous tyrannosaurids, including the iconic Tyrannosaurus rex sported a coat of feathers.  At Everything Dinosaur, we have known about the fossils upon which this research is based, for some time.  Indeed, we are aware of a number of research projects taking place exploring the evidence for integumentary coverings in the Dinosauria.  This new study looks at skin impressions from several Late Cretaceous, giant Tyrannosaurs and concludes that despite early tyrannosauroids having feathers, T. rex and its near relatives, most likely had scaly skin.

A Fluffy, Feather Covered Tyrannosaurus rex

A feathered T. rex

A feathered Tyrannosaurus rex!  Or at least, a partially feathered T. rex but more about that later.

The research has generated some surprising headlines, looks like many media outlets have got into a bit of a flap:

“Feather furore: T. rex may not have been fluffy after all, skin study suggests” – The Guardian.

“Tyrannosaurus rex had scaly skin:  Here are the controversial reasons why scientists think the dinosaur was NOT covered in feathers” – Mail Online

“Jurassic Park may have been right about the T-rex after all” – Silicon Republic

“Here’s what it would feel like to pet a T. Rex” – National Geographic

Some quick points:

  • If you publish a story that features Tyrannosaurus rex lots of media outlets are likely to cover it.
  • You can expect some sensational headlines.
  • Expect numerous faux pas when it comes to the “Tyrant Lizard King” – rapped knuckles for Silicon Republic and National Geographic!  No hyphen in T-rex, no capital letter for the trivial name etc.

What Does the Study Show?

The research team led by Dr Phil Bell (University of New England, New South Wales, Australia), examined the fossilised skin impressions associated with a partial skull and postcranial material of a Tyrannosaurus rex specimen “Wyrex” from the Hell Creek Formation of Montana.  These fossils are part of the vertebrate fossil collection at the Houston Museum of Natural Science, hence one of the co-authors, Robert T. Bakker’s (curator of palaeontology at the Houston museum), involvement in the study.  The specimen represents around 30% of an entire skeleton, it was excavated from upper Maastrichtian strata near the town of Baker (Montana), in 2003 and it was formerly part of the Black Hills Institute fossil collection (BHI 6230), hence the participation in the study by Pete Larson (Black Hills Institute of Geological Research, South Dakota).  The gracile form of the skeleton suggests that “Wyrex” was male.

Preserved Skin Impression on the Neck of “Wyrex”

Tyrannosaurus rex skin impression.

Preserved integument from the neck (b) of T. rex specimen HMNS 2006.1743.01

Picture Credit: Biology Letters

“Wyrex” is special, as in association with the fossilised bones and teeth, several patches of the integument are preserved as impressions.  These impressions represent skin from the neck, the pelvic area and from the tail.  The tail skin impressions are the most numerous, but all of them combined do not represent a very large part of the surface area of a T. rex.  The patches are very small ranging in size from less than a postage stamp in area to an impression of approximately 30 square centimetres, a tail skin impression that that would have covered less than a third of the screen on an average mobile phone.  Although these impressions are very small, any form of integument preservation is remarkable and they have provided an invaluable insight.

Integument of Tyrannosaurus rex (HMNS 2006.1743.01)

The extent of the skin impressions.

The extent of the skin impressions on the “Wyrex” specimen.

Picture Credit: Biology Letters

The picture above shows impressions and where they are located on the T. rex (see silhouette).  Three bones are shown (a), they are bones from near the base of the tail (caudal vertebrae 6-8) which are associated with skin impressions (f), (g) and (h).  Integument from the neck (b, c) and from the ilium (pelvis) in (d, e).  The line drawings show the great variation in the size and shape of the scales.  The researchers highlight the variety of the scales, some are elliptical, some are elongated, whilst others are irregular six-sided polygons.

Note the scale bars, in a lot of the media coverage, the actual size of the impressions has not been reported, the scale bars in the picture above:

(a) = 10 centimetres, (b-e) = 5 millimetres and (f-h) = 10 millimetres

Not Just T. rex Skin in the Study

To the north of Montana, lies the Canadian Province of Alberta.  Geography lesson over, but noting the location of Montana is significant, as scientists from the University of Alberta and the Royal Tyrrell Museum (also in Alberta), have played a part in this research.  Illustrious figures from the world of palaeontology such as Professor Phil Currie and Scott Persons (University of Alberta) and Darren Tanke (Royal Tyrrell Museum).  These luminaries along with Nicolás Campione (Uppsala University, Sweden), have helped compile a new data set plotting tyrannosauroid integument against body size.  This study looked at fossil skin impressions from a number of other Late Cretaceous relatives of T. rex, monsters such as Albertosaurus, Gorgosaurus, Daspletosaurus, all from North America, plus Tarbosaurus from Asia.

The Late Cretaceous Daspletosaurus (Fossils found in Montana and Alberta)

A sitting Daspletosaurus.

The fearsome tyrannosaurid Daspletosaurus.  Note the absence of feathers.

Picture Credit: Everything Dinosaur

The research team conclude that these large-bodied forms possesses scaly, reptilian-like skin.  By mapping integument against body size against the tyrannosauroids, a more extensive data set than just the Tyrannosauridae family, the team postulate that large body-size evolved two times in the evolutionary history of this substantial group.  Early tyrannosauroids such as Yutyrannus (Y. huali), which was feathered, was part of one branch of the tyrannosauroids that became giants and gigantism occurred again in later tyrannosaurids such as T. rex, Gorgosaurus, Albertosaurus et al.

The data suggests that shaggy, feathery coats as found in some early tyrannosauroids, were lost by the Albian faunal stage (around 112 million years ago).  Later Tyrannosaurs, those that were the ancestors of the very last members of the Tyrannosauridae to evolve, did not have feathery coats.

 Yutyrannus Roamed Northern China 125 Million Years Ago

A flock of Yutyrannus.

Giant Theropod with feathers from Liaoning Province

Picture Credit: Brian Choo

To read an article about the discovery of Yutyrannus hualiOne Tonne Feathered Tyrannosaur

Yutyrannus – A Tyrannosaur Game Changer

The discovery of a large (up to nine metres long and weighing 1.4 Tonnes), Tyrannosaur provided evidence that giant Theropods could have been covered in a shaggy coat.  Prior to the description of Y. huali (the name means beautiful feathered tyrant), back in 2012, the only Tyrannosaurs discovered with proto-feathers were much smaller animals, dinosaurs such as Dilong, (D. paradoxus), which also roamed China.  It had been thought that smaller Tyrannosaurs, with their warm-blooded metabolisms evolved feathers to help keep their bodies insulated.  However, here was a much larger dinosaur, one that was also covered in feathers.

In this new research, the scientists conclude that the environment that Late Cretaceous giants such as Albertosaurus and T. rex lived in had a similar climate to the environment that Yutyrannus lived in millions of years before.  They discount the idea that the big Late Cretaceous Tyrannosaurs had feathers to keep them warm.  The larger the animal, the smaller the surface area compared to their volume and therefore big creatures tend to be better at retaining heat than smaller ones.  In the paper, it is argued that a big, thick coat of feathers may have been a real hindrance to a Tyrannosaurus rex, as its active lifestyle could have given it serious problems with over-heating.

A Close View of the Skin Impression over the Pelvic Area (Ilium) of T. rex

Scales on a T. rex.

T. rex integumentary covering over the ilium.

Picture Credit: Biology Letters

Tyrannosauroid versus Tyrannosauridae

The assessment of these scale impressions along with the analysis of tyrannosauroid integument against body size does not necessarily mean that T. rex was definitely covered in scaly skin.  This new research may cast doubt on the idea of an adult, Late Cretaceous Tyrannosaur looking like a giant chicken, but it is important to note that the researchers comment that dinosaurs such as Albertosaurus, Gorgosaurus and T. rex may have had feathers on those parts of the their body which are not represented by skin impressions in the fossil record – on their backs, or around the top of the head for example, hence the partially feathered Tyrannosaurus rex image featured in this article.  As juveniles, having an insulating covering of downy feathers does make anatomical sense.  The idea that members of the Tyrannosauridae may have had feathers at some stage of their lives cannot be discounted in the same way as that stating that T. rex may have had feathers on some parts of the body cannot be discounted as we lack the fossil evidence to disprove this statement.

The scientists do state that whilst more basal members of the Tyrannosauroidea may have had feathers, later more derived Tyrannosaurs, those animals within the family Tyrannosauridae probably did not.   The key word to note is “probably”.

Let’s quickly explain what this means.

The Tyrannosaurs are a very ancient lineage of dinosaurs, they evolved in the Jurassic and persisted right up until the Cretaceous mass extinction event.  The clade Tyrannosauroidea represents the family Tyrannosauridae, to which Albertosaurus, Tarbosaurus, Gorgosaurus, Daspletosaurus and T. rex are part, along with more basal, earlier Tyrannosaurs.

Tyrannosauroids and Tyrannosauridae Explained

Tyrannosauroids and Tyrannosauridae members.

The difference between the Tyrannosauroidea and the Tyrannosauridae.

Picture Credit: Everything Dinosaur

In the simplified diagram above, the Tyrannosauridae family is shown as being a part of the larger Tyrannosauroidea clade.  Some well-known examples of the Tyrannosauroidea clade as well as members of the Tyrannosauridae family are listed.

The Preservation Factor

Only in very exceptional circumstances can delicate feathers and proto-feathers be preserved.  Tough skin has a better preservation potential than filamentous feathers that formed a shaggy coat.  Feathers could have been present in members of the Tyrannosauridae, but they simply have not been preserved, so we have no evidence of their existence.  Experiments revealing how the corpses of birds decay may help palaeontologists to better understand what happens to feathers after death and their likelihood of being preserved.

Conclusions

In what is a thought provoking and well-argued piece, the scientists comment that their findings reveal significant changes within the integument of tyrannosauroids, especially when compared to skin impressions of later members of the Tyrannosauridae.  These changes in body coverings require better understanding and further evidence to help palaeontologists to explain them.  The unambiguous loss of extensive body coverings in the Tyrannosauridae merits further discussion.

To mark the publication of the Biology Letters article, we cooked chicken.  We left the skin on and from the picture below, you can see the skin but there are no signs of the feathers that would have covered parts of the bird.  We suspect that this debate over the appearance of more derived Tyrannosaurs is going to rumble on.

Commemorating the Publication with a Chicken Dish

Cooked chicken showing the skin.

Cooked chicken, you can see the skin but not much evidence of feathers.

Picture Credit: Everything Dinosaur

Which Do You Prefer Feathered or Non-Feathered?

Did T. rex have feathers?

Which do you prefer a feathered or a non-feathered T. rex?

The scientific paper: “Tyrannosauroid Integument Reveals Conflicting Patterns of Gigantism and Feather Evolution”, by Phil R. Bell, Nicolás E. Campione, W. Scott Persons, Philip J. Currie, Peter L. Larson, Darren H. Tanke, Robert T. Bakker published in the Royal Society Biology Letters

6 06, 2017

Foul-mouthed Study – Variation in Duck and Goose Beaks

By | June 6th, 2017|Animal News Stories, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Diet Shaped the Evolution of the Beaks of Ducks and Geese

For Aaron Olsen, a walk in a park to see the ducks and other birds serenely swimming on the local pond has added significance.  Ducks and geese, common waterfowl that we are all familiar with, have fascinated the postdoctoral researcher at Brown University (Rhode Island, USA).  For Aaron, seeing gaggles of geese and rafts of ducks has led him to question how such a myriad of different beak forms have evolved within the waterfowl clade (Anseriformes).  Publishing in the academic journal “Functional Ecology”, the scientist has concluded that different diets and different feeding strategies are the main drivers of beak shape.

The Beaks of Ducks and Geese Come in All Shapes and Sizes

Anseriformes - skulls variation due to dietary preferences.

From left to right a gradient of duck-to-goose-skulls.  Research shows that waterfowl beaks vary primarily because of differences in diet and feeding behaviour.

Picture Credit: Aaron Olsen

Ancient Anseriformes (Prehistoric Ducks)

The analysis of the relationship between beak shape and diet amongst waterfowl shows that feeding is most likely to be the major influence on bill shape, but it also suggests that the early members of the Anseriformes were more like ducks than geese.  The main evolutionary driver when it comes to the shape of the beaks of waterfowl is their diet.

Commenting on his research, Aaron Olsen, of the Department of Ecology and Evolutionary Biology at Brown University stated:

“This is the most comprehensive look to date at the relationship between diet and beak shape.”

The oldest member of the Anseriformes is Vegavis (V. iaai), fossils of which have been found in Upper Cretaceous rocks (Maastrichtian faunal stage) of Antarctica.  Waterfowl, the ancestors of today’s ducks and geese were present some 66 million years ago, although their evolutionary roots probably go back further into the Mesozoic.

Vegavis of Late Cretaceous Antarctica

The vocalisation of dinosaurs and birds.

Vegavis takes off whilst a male Theropod dinosaur vocalises close by.

Picture Credit: Nicole Fuller/Sayo Art for University of Texas at Austin

Scientists have identified the vocalisation organ of Vegavis, this bird may have made a honking sound.

To read more about this research: Ancient Bird Box Sheds Light on the Sounds of Early Anseriformes

Waterfowl – Different Beak Shapes

Whilst working at the University of Chicago and the nearby Field Museum of Natural History, Aaron set out to explore the reasons why waterfowl have such differently shaped beaks.  He suspected that diet and feeding behaviour might play a pivotal role in beak morphology, but rather than compare diets and feeding strategies he undertook a detailed three-dimensional analysis of bird skulls and their bills.  He then cross-referenced his findings with literature on the diet of each bird.  A total of 136 specimens were involved in the study, covering 46 genera and 51 species.  As well as looking at living species, the study included an analysis of the recently extinct, flightless duck Thambetochen chauliodous of the larger Hawaiian Islands (except Hawaii), which prior to the arrival of domesticated animals, were the main browsers of vegetation on the isolated archipelago.  The research also involved an analysis of the skull and beak of a much older water bird – Presbyornis spp. from the Palaeocene and the Eocene Epochs.

Extant Goose Skull and Extant Duck Skull Compared to the Ancient Anseriform Presbyornis

Comparing duck and goose skulls.

A Cape Barren goose skull (top) has a very different beak than that of a freckled duck (middle), which does resemble the fossil skull of Presbyornis (bottom).

Mathematical Analysis – Plotting Beak Evolution

Data analysis revealed that there was a strong correlation between dietary preferences and beak shape.  Ducks tend to have relatively long, wide-tipped beaks that can accommodate a lot of water. Ducks feed by filtering out food such as invertebrates and plant seeds from water, whereas geese evolved to feed on the leaves and roots of plants (although some still filter feed).  Most geese have shorter, narrower beaks better designed for browsing on plants.

Dr Olsen contends that the correlation between beak morphology and diet is so strong that other roles for beaks, such as preening and cooling would have had little influence, although he does not rule out these other functions having a role in the evolution of beak shape.

First Ducks Then Geese

In a review of the scientific literature, Aaron, a specialist in Anseriform research, suggests that the early ancestors of extant ducks, geese and other related waterfowl, were very duck-like.  Geese-like beaks evolved later, evolving several times in several places.  In summary, Dr Olsen concludes a duck-like beak is ancestral for most waterfowl with several independent transitions to a more goose-like beak shape occurring over time.

Next time you are in the park, take a look at the ducks and other water birds, the ancestors of these birds lived alongside the dinosaurs.  It’s also worth noting that ducks and geese are technically dinosaurs too, after all, they are all members of the Theropoda.

Non-Avian Dinosaurs and Avian Dinosaurs (Birds)

Dinosaurs and birds.

Avian and non-avian dinosaurs.

Picture Credit: Everything Dinosaur

The scientific paper: “Feeding Ecology is the Primary Driver of Beak Shape Diversification in Waterfowl”, by Aaron M. Olsen published in Functional Ecology.

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