All about dinosaurs, fossils and prehistoric animals by Everything Dinosaur team members.
21 05, 2013

The Schleich Styracosaurus Dinosaur Model Reviewed

By | May 21st, 2013|Everything Dinosaur Products, Everything Dinosaur videos, Product Reviews|2 Comments

Everything Dinosaur Reviews the Schleich Styracosaurus Dinosaur Model

The second new dinosaur model to be introduced by Schleich into their World of History/Prehistoric Animals series this year, is a colourful model of a Styracosaurus.  After reviewing the Schleich Carnotaurus earlier in the month, it seemed only fair that we give this flamboyant spiky dinosaur some time in the spotlight.

Everything Dinosaur’s Review of the Schleich Styracosaurus Dinosaur Model

Video Credit: Everything Dinosaur

To view the Schleich prehistoric animal models available from Everything Dinosaur: Schleich Prehistoric Animal Models

In this brief video review (5 minutes and 36 seconds) we discuss the merits of this herbivorous dinosaur replica and look at the spectacular eye-spots that the design team at Schleich have decided to give their Styracosaurus.  2013 marks the centenary of the naming and describing of this Centrosaurine.  It seems apt for Schleich to introduce a model of this dinosaur to mark the 100th anniversary of the naming of Styracosaurus.

20 05, 2013

BBC Series “Ice Age Giants” Episode 1 Reviewed

By | May 20th, 2013|TV Reviews|2 Comments

Episode One of “Ice Age Giants” Focuses on the Laurentide Ice Sheet

The BBC have put together a television series featuring the Mammalian “megafauna” of the Pliocene and the Pleistocene Epochs with a focus on the Ice Age – hence the title of the three-part series “Ice Age Giants”.  The first episode was entitled “Land of the Sabre-Tooth” and focused on the impact of the immense Laurentide ice sheet on North America.  With the assured Professor Alice Roberts, an anatomist (human anatomy that is), by training at the helm and undertaking the presenting duties the programme was up to the high standards expected of the BBC.

The first episode focused on a number of the large mammals that lived south of the two mile high Laurentide ice sheet that covered much of the continent, over thousand of years the ebbs and flows of the ice sheets led to the creation of some very rich and verdant plains and swamplands, these were home to an array of bizarre mammals, with only a few remnants of the Ice Age megafauna left today, animals such as the bison and the elk.

The Sabre-Tooth Cat, (Smilodon fatalis) was the star of the first programme with a focus on the latest theories about how those huge canines could have been used to kill prey.  The CGI was not overplayed, although the scene in which a single cat chases down and catches a horse did not look particularly authentic to our team.  Smilodon fatalis had immensely powerful arms and shoulders, this point was made in the documentary, however, the impact on this cat’s ability to run was not explored fully.  Most certainly, these apex predators specialised in big game, but they probably were not out and out pursuit predators, but more likely to have been ambush predators having to get very close to any potential victim before launching an attack.

The Magnificent Smilodon – One of the Stars of the Series

The famous "Sabre-Toothed Cat" - Smilodon.

The famous “Sabre-Toothed Cat” – Smilodon.

Picture Credit: BBC

It is incorrect to refer to these members of the Felidae as “Sabre-Toothed Tigers” to read Everything Dinosaur’s explanation: Sabre-Toothed Cats not closely related to Extant Tigers

The astonishing degree of preservation of the dung of the Shasta Ground Sloth (Nothrotheriops shastensis) and what the metre thick sediments found in caves in the Grand Canyon walls can tell us was the highlight.  Dating techniques have permitted scientists to plot exactly when these cow-sized sloths abandoned the Grand Canyon area and when they returned.  These results tie in very nicely with known ice age extensions and warmer inter-glacial periods.  It is amazing what you can learn from a 20,000 year old ball of dung.

It was pleasing to see that South American immigrant, the Glyptodont getting a look in.  Once thought of being a creature of the open plains, it seems that a substantial population thrived in the swamplands that once covered much of Arizona.  The explanation as to why most Glyptodont fossils are found upside down was interesting as was the the theory that these distant relatives of anteaters, sloths and armadillos may have had trunks.

An Illustration of a Typical Glyptodont

Bizarre armoured giant with a furry underside, a shell on top and a bony tail often with a club on the end.

Bizarre armoured giant with a furry underside, a shell on top and a bony tail often with a club on the end.

Picture Credit: Everything Dinosaur

The polished faces of boulders being presented as evidence of these rocks being used as giant scratching posts as herds of giant Columbian Mammoth (Mammuthus columbi), was something new to us, we had not read about this in any literature.  Most probably many animals used these outcrops as scratching posts over millenia, but the fourteen foot high polished areas could only have been made by something as big as a Columbian Mammoth.  That said, this part of California has been subjected to sizeable earthquakes and the land may have been raised somewhat, especially with the retreat of the heavy ice sheets, so it has to be presumed for the Columbian Mammoth theory to be accepted then these rocks would have had to remain somewhat “in situ”.

Interesting to see the many fossils from La Brea Tar Pits, a part of Los Angeles that team members at Everything Dinosaur have been lucky enough to visit.  The pathology, suspected sceptic arthritis on a pelvis and its potential implications on the social nature of Sabre-Tooths was very well explained.  Intriguingly, there was no mention of the proposed Californian sub-species of Sabre-Toothed Cat.  The tar pits at Rancho La Brea in Los Angeles have produced a lot of fossil material relating to the Smilodon genus (mainly S. californicus and not S. fatalis).  Everything Dinosaur has followed the work on the material removed due to the building of the underground library car park with great interest since excavations began back in early 2011.  We refer to the crates of sediment taken out as part of the ground works for the library as “box cart palaeontology”.

To read more about the “box cart” excavations at Rancho La Brea: Huge Haul of Ice Age Fossils from La Brea

All in all, a promising start to this series and we are already looking forward to episode two.

19 05, 2013

Flim Star Honoured by Having Fossil Arthropod Named After Him

By | May 19th, 2013|Dinosaur and Prehistoric Animal News Stories|0 Comments

Edward Scissorhands (Johnny Depp) Honoured by Having Cambrian Arthropod Named After Him

The 1990 film Edward Scissorhands (directed by Tim Burton), starred Johnny Depp as a boy with scissors for hands.  A new genus of Cambrian Arthropod, a strange four centimetre long creature that is distantly related to extant, marine Arthropods such as crabs and lobsters, which also had scissor-like appendages has been named in honour of the actor.

Naming a new creature after a famous person is nothing new, for example, a number of dinosaurs have been named after wealthy benefactors and people who have supported the sciences.  Back in 2011 a new species of horned dinosaur, Pachyrhinosaurus perotorum was named in recognition of the Perot family (Margot and H. Ross Perot), for their support of the Museum of Science and Nature in Dallas, Texas.  The author Herman Melville, he of “Moby Dick” fame has had a species of toothed whale named after him, but it is rare for an actor portraying a fictional character to be honoured in this way.

The animal has been named Kooteninchela deppi (pronounced as Coo-ten-ee-che-la depp-eye).  The fossil has been dated to around 505 million years ago (Late Cambrian).  It was during the Cambrian period that virtually all the pre-cursors to modern animals evolved.  Author of the scientific paper, published this month in the academic publication “The Journal of Palaeontology”, David Legg  commented that:

“When I first saw the pair of isolated claws in the fossil records of this species I could not help but think of Edward Scissorhands.  Even the genus name, Kootenichela, includes the reference to this film as ‘chela’ is Latin for claws or scissors.  In truth, I am also a bit of a Depp fan and so what better way to honour the man than to immortalise him as an ancient creature that once roamed the sea?”

An Illustration of Kootenichela deppi

Strange, clawed Cambrian Arthropod.

Strange, clawed Cambrian Arthropod.

Picture Credit: AFP/Getty Images

Scale Bar: Everything Dinosaur

The fossil, which comes from Canada, (British Columbia), represents an animal that lived in warm, shallow waters part of a rich and diverse marine ecosystem dominated by Molluscs and Arthropods with the very first ancestors of the Chordates (animals with backbones), playing only a minor role.

K. deppi  had a flattened, segmented body with pairs of legs associated with the majority of its trunk segments.  It probably scuttled along the sea floor but was probably capable of swimming short distances by flexing its body from side to side.  It is not known what the scissor-like appendages were used for.  This Arthropod that lived alongside the Trilobites, may have scavenged the carcases of other creatures that had died and sank to the bottom of the sea.  Or perhaps, it used its strange claws with their elongated spines to probe in the sediment so as to capture soft-boded creatures like segmented worms.  Like many Cambrian Arthropods, it has large compound eyes, with each lens made of calcite.  Each eye was positioned on top of a movable stalk (a peduncle).  This would have given this two inch long Arthropod excellent vision, even in low light and it could have buried itself in soft mud, leaving its eyes sticking out so that it could keep a look out for any predators whilst remaining difficult to spot.

A Close up of the Strange Claw-like Appendages

Are these the offensive weapons of a predator?

Are these the offensive weapons of a predator?

Picture Credit: Imperial College/Journal of Palaeontology

David’s research led him to conclude that Kooteninchela deppi belongs to a group known as the ‘great-appendage’ Arthropods, or Megacheirans, (big hands), which refers to the enlarged pincer-like frontal claws that they share.  The Megacheirans are a diverse clade, fossils of which have been found in many parts of the world including the famous Burgess Shale deposits and Cambrian aged strata in China.

David went onto state:

“Just imagine it: the prawns covered in mayonnaise in your sandwich, the spider climbing up your wall and even the fly that has been banging into your window and annoyingly flying into your face are all descendants of Kooteninchela deppi.  Current estimates indicate that there are more than one million known insects and potentially 10 million more yet to be categorised, which potentially means that Kooteninchela deppi has a huge family tree.”

The researcher hopes to extend his study of ancient Arthropods with the aim of learning more about the radiation of these armoured creatures and how ancient Arthropods gave rise to the huge range of extant Arthropods found today, including the insects.

It seems that the inspiration behind Edward Scissorhands was not a first, such a creature with claw-like appendages had evolved some five hundred million years earlier.

18 05, 2013

Doting Dinosaur Dads – Might Not Be the Case

By | May 18th, 2013|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans|3 Comments

Male Dinosaurs May Not Have Looked after the Nest After All

Back in December 2008, Everything Dinosaur published details of an academic paper that concluded that male Theropod dinosaurs undertook the majority of the brooding of eggs in nests.  Dr. David Varricchio (Montana State University) and his colleagues assessed the known nest fossil material of three Theropod dinosaurs from Upper Cretaceous strata.  The dinosaurs studied were Citipati osmolskae, Oviraptor philoceratops (both Oviraptorids) and Troodon formosus (Dromaeosaurid – whoops corrected Troodontid).  The team used a number of methodologies to conclude that, just like 90% of the birds species alive today, it was the male Theropods who did most of the brooding on the nests.  The conclusions were reached after examining fossils for evidence of bone cavities associated with the loss of calcium from the body in order to produce egg shell.  Such cavities would be expected to be seen only in females.  Since none of the fossil bones included in the study showed such cavities, it was suggested that the individual dinosaurs found in close proximity to a nest of their own species were probably male.

A Close up of a Theropod Dinosaur Nest

New study casts doubt on the "doting dinosaur fathers" theory.

New study casts doubt on the “doting dinosaur fathers” theory.

The number of eggs laid per nest compared to the body size of the adult dinosaur supported this view that the brooding dinosaurs were male.   The study proposed that Theropod dinosaurs produced unusually large numbers of eggs per nest for their body size.  This pattern is often seen in extant Aves (bird species alive today), when the male alone takes on the parental duties.  The female can afford to lay more eggs, as she will not be looking after them so she can be away from her maternal duties and get back to feeding herself up to replenish lost reserves in her body.  So it was concluded that the Theropod males brooded the nest and probably played a significant role in looking after the hatch-lings.

To view an article on the original research: Doting Fathers – A Dinosaur Trait Passed Onto Birds

However, scientists from the University of Lincoln (England), have reviewed the data used in the 2008 study and they have come up with a different interpretation of the fossil evidence.

It is very difficult to infer behaviour, especially something as complicated as parental behaviour with just the fragmentary fossil record to go on.  In the review of the 2008 research, a number of factors known to affect egg and clutch sizes in living bird species were not taken into account.  A new scaling analysis of the clutch masses of birds suggests that the type of parental care may not be inferred.  The evolutionary relationship between the Theropods and Aves may be widely accepted but this does not necessarily mean that these two types of creature raised their young in the same or similar ways.   The maturity of the hatch-lings precocial (independent  young) or altricial (dependent young) would have a significant bearing on the behaviour of the parents.  Intriguingly, the new study from the University of Lincoln team suggests that most Theropods seem to exhibit precociality (hatch-lings born relatively mature and independent to a degree from their parents).

The male Theropod dinosaurs may not have been such dedicated dads after all.

Dr. Charles Deeming (School of Life Sciences) and his Lincoln University colleagues point out a number of factors that need to be considered before attempting to work out how adult Theropods behaved around the nest.  Dr. Deeming specialises in the study of avian and reptilian reproduction, he is very well placed to compare extinct fauna with extant descendants.  For example, a number of bird species today, deliberately lay their eggs in another bird’s nest so as to avoid any form of parental responsibility at all.  This will distort the size of some nests, Theropod dinosaurs may have behaved in the same way.  There are evolutionary advantages when it comes to getting others to do work for you.

Oviraptorid Nests were Part of the Study

Dinosaur nests carefully examined.

Dinosaur nests carefully examined.

Picture Credit: Cincinnati Museum Centre

Dr. Deeming and his team took a different approach to the statistical analysis.  They counted the eggs in all known fossil nests for the Theropod species included in the original study and then worked out an average clutch size for each species.  Dr. Varricchio and the Montana State University researchers had based their calculations on the largest clutch size for each dinosaur species.

When the British-based team compared their average figures with the adult dinosaur body mass, they found that the Theropod dinosaurs were not included in the group of male-only brooders.

Commenting on the earlier research, Dr. Deeming stated:

“The Varricchio analysis is now being used by other palaeontologists working on other dinosaur species.  It’s time to stand up and say it doesn’t quite work.”

For Dr. Varricchio, the new insight is most welcome, but he warns:

“Regardless of what this paper or our paper says, we are really operating with only a few pieces of the puzzle.  To address the [parental] care in these dinosaurs, one needs to consider their other relatives and not just birds.  For instance, crocodiles, which share a common ancestor with all dinosaurs, might be one source of clues to dinosaur brooding behaviour.”

The two research teams are agreed on certain points, there is a need for further study and looking at the nests of crocodiles may yield useful data.

Dr. Deeming added:

“If you look at the eggs in those dinosaur nests, they’re structure is similar to crocodile eggs.”

Crocodilians bury their eggs and the temperature at which the nest is kept is essential for healthy hatch-lings, the temperature of the nest also determines the sex of the offspring.  A buried nest hypothesis would add an additional and very significant factor to any parental behaviour study.

Dr. Deeming concluded by saying:

“Crocodiles don’t incubate their eggs, they just sit on the buried eggs to protect them from predators.  I think that’s probably what was going on in the dinosaurs too.”

It is difficult to assign behaviour to fossil material, in the absence of a time machine and an ability to travel back to the Late Cretaceous to observe Oviraptorids and Dromaeosaurs in the breeding season, this debate is likely to rumble on.

17 05, 2013

Dinosaur Party Food Labels

By | May 17th, 2013|Everything Dinosaur News and Updates|0 Comments

Dinosaur Party Food Labels for Your Little Monsters

Everything Dinosaur was asked the other day by a customer how to encourage children to try different party food.  This is no mean task as young children tend to eat in what we call the “tsunami” style and we are not referring to the mess that a dozen or so excited, enthusiastic dinosaur fans can cause at a dinosaur themed party.  If one child tries something then others will follow, by the same token if one child rejects some item of dinosaur party food then those around him or her are likely to do the same.

To avoid such problems and in order to help offer a range of healthy dinosaur party food, Everything Dinosaur has created a couple of simple dinosaur themed party food labels.   Staff get emailed: Contact Us and our dedicated team members email out two dinosaur themed labels for party food.  Each label features a different dinosaur, a meat-eater (Concavenator) for those food items which are meat-based and a second label with a herbivorous, horned dinosaur (Kosmoceratops).  This second label can be used for non-meat based food items.  The box under the dinosaur image is for grown ups preparing the food to write a description.  Mums and dads can get quite creative with labels such as “Sauropod salad”, “Cretaceous cheese sandwiches” and “Jurassic jam”.

One of the Everything Dinosaur Party Food Labels (Dinosaur Themed Party)

Kosmoceratops encourages young children to eat their greens.

Kosmoceratops encourages young children to eat their greens.

Picture Credit: Everything Dinosaur

The labels have proved very popular and it is amazing how quickly young children will tuck into a salad if it is labelled with a dinosaur.  The pictures can be coloured in and they make a useful addition to the check list of dinosaur themed items required to help make a dinosaur party a roaring success.

16 05, 2013

Fossilised “Fish Lizard” from Iraq Changing the Way we View Ichthyosaur Evolution

By | May 16th, 2013|Dinosaur and Prehistoric Animal News Stories, Palaeontological articles|0 Comments

Ichthyosaur Evolution Just Got a Lot More Complicated

Ichthyosaurs were a group of marine reptiles that superficially resembled dolphins.  These streamlined, viviparous (giving birth to live young), predators seem to have evolved in the Early Triassic and became extinct towards the end of the Cretaceous.  Ichthyosaur fossils have been found all over the world, however, despite the wealth of fossil material (or perhaps because of it), there are a number of mysteries surrounding this Order that puzzle palaeontologists.  For instance, they do seem to be at least superficially, the best adapted to life in a marine environment when compared to the other types of marine reptile, the crocodile-like Metriorhynchids, the Mosasaurs, the long-necked Plesiosaurs and their shorter-necked relatives the Pliosaurs.  However, despite being very well suited to a nektonic lifestyle and there being a growing body of evidence to suggest that these types of “fish lizards”, were becoming better and better adapted to life in the open oceans as the Jurassic gave way to the Cretaceous, they still became extinct long before the Cretaceous mass extinction event that saw the demise of the other types of Late Cretaceous marine reptile.

A Scale Drawing of a Typical Ichthyosaur

A typical "dolphin-like" Ichthyosaur.

A typical "dolphin-like" Ichthyosaur.

Picture Credit: Everything Dinosaur

The Order Ichthyosauria suffered a series of extinctions with three major extinction events identified over the duration of the Mesozoic.  As a result, those types of Ichthyosaur that survived into the Cretaceous from this Order’s Jurassic heyday were believed to a single branch of what had been a diverse clade.  The Cretaceous Ichthyosaurs were all relatively similar in their body plans and morphology and were believed to have shared a common Late Jurassic ancestor.  The lack of variation in Cretaceous Ichthyosaur body types, the general lack of diversity in the Ichthyosauria, was believed to have played a significant role in their ultimate demise during the Cenomanian faunal stage of the Cretaceous.

The publishing of a scientific paper (Biology Letters), outlining the research undertaken on a partial Ichthyosaur fossil specimen found in Iraq, may change the way in which the Cretaceous Ichthyosaurs are viewed.  This Ichthyosaur, named as Malawania anachronus (Mal-ah-won-nee-ah a-nack-kron-us), seems to contradict the long-held theories.  Malawania represents a “ghost lineage of Ichthyosaurs”, it resembles a more primitive form of this marine reptile Order, it does not appear to be closely phylogenetically related to other known Cretaceous Ichthyosaurs.

The fossil which consists of fragments of skull bones including a partial sclerotic ring (ring of bone around the orbit) and much of the front portion of the animal was discovered by British geologists exploring Kurdistan (north-eastern Iraq) in the 1950s.  At the time of its discovery, the slab of fossil material was not being treated with much reverence.  As one of the authors of the scientific paper outlining the study of this fossil, Dr. Darren Naish points out:

“Preserved within a large, flat slab of rock, it was being used as a stepping stone on a mule track.”

The Fossilised Remains of Malawania anachronus

The picture shows the fossil slab and a drawing illustrating the location of the fossil material.

The picture shows the fossil slab and a drawing illustrating the location of the fossil material.

Picture Credit: Biology Letters

Study of the specimen began during the 1970s with Ichthyosaur expert Robert Appleby, then of University College, Cardiff.  Although he recognised the significance of this fossil discovery, he unfortunately passed away before determining the precise age of the specimen.  However, the research into this strange Ichthyosaur, one of only two Ichthyosaur fossils known from the Middle East, was taken up recently by a team of international scientists and fittingly the contribution of Robert Appleby is acknowledged as he is credited on the list of authors for the scientific publication.

The research team conclude that this fossil contradicts the previous theories about the evolution and extinction patterns seen in the Ichthyosauria.  Lead author Dr. Valentin Fischer (University of Liege, Belgium) and his colleagues have named the specimen Malawania anachronus, the name means “out of time swimmer”, as despite being Cretaceous in age, the Ichthyosaur represents the last known member of a kind of Ichthyosaur which was believed to have become extinct during the Early Jurassic.  Analysis of the micro-fossils found on the slab of rock which contains the Ichthyosaur specimen, analysis of spores and pollen grains that have been preserved indicate that this Ichthyosaur lived approximately 125 million years ago (Barremian faunal stage of the Early Cretaceous).  The research team support this assertion by providing a cladistic study of the known Ichthyosaur fossil material to re-design the “Fish Lizards” family tree.  Here is evidence of a ancient, primitive Ichthyosaur assigned to the Thunnosauria group of Ichthyosaurs that seem to have originated in the Late Triassic.  This study suggests that in some parts of the world, primitive Ichthyosaurs survived relatively unchanged for more than sixty million years.

Commenting on the implications for this research, Dr. Fischer stated:

“Malawania’s discovery is similar to that of the Coelacanth in the 1930s: it represents an animal that seems ‘out of time’ for its age.  This ‘living fossil’ of its time demonstrates the existence of a lineage that we had never even imagined.  Maybe the existence of such Jurassic-style Ichthyosaurs in the Cretaceous has been missed because they always lived in the Middle-East, a region that has previously yielded only a single, very fragmentary Ichthyosaur fossil.”

The phylogenetic analysis undertaken by the research team suggests that several Ichthyosaur groups that appeared   during the Triassic and Jurassic geological periods may have survived into the Cretaceous.  This brings the extinction phases of the Ichthyosauria into doubt.  For example, according to this new study, the supposed end of the Jurassic extinction event may not have occurred.  The fossil record for the Ichthyosauria shows a very different pattern of extinction when compared to known, accepted data on other marine reptile groups.

The Evolution of the Ichthyosauria

A table compiled by the research team that explores the evolution and radiation of the Ichthyosauria.

A table compiled by the research team that explores the evolution and radiation of the Ichthyosauria.

Table Credit: Biology Letters

The position of Malawania anachronus is shown by the red line.  The chart at the top records the passage of time from the Middle Triassic to the Late Cretaceous and places known fossil material on this chronological scale.  The line graph below shows the proposed main periods of radiation of the Ichthyosauria and the herring bone diagrams at the bottom shows the proposed phylogenetic relationship between different genera.

When this research is taken together with the 2012 literature on the discovery of a new species of German Ichthyosaur known as Acamptonectes densus, another type of Ichthyosaur known as an Ophthalmosaur that may have survived into the Cretaceous, the discovery of Malawania revolutionises how palaeontologists view the evolution of this type of marine reptile.

To read more about this discovery: New Ichthyosaur Species Swims into View

There is growing evidence to suggest that the Ichthyosaurs remained an important and diverse group of marine reptiles, at least into the Early Cretaceous.  If this is the case, then their extinction some ninety million years ago becomes even more of a mystery.  Why did this diverse and seemingly superbly adapted Order of marine reptiles die out?

A spokesperson from Everything Dinosaur suggested:

“This new research certainly muddies the waters somewhat when it comes to the final demise of the Ichthyosauria.  If they had been a small, homogeneous group filling very similar niches in the food-chain of the oceans then they could have been very vulnerable to extinction.  However, this new evidence suggests that this was not the case, the Ichthyosaurs were more diverse than previously thought.  Perhaps the evolution and rapid radiation of the Teleosts (modern ray-finned fishes) had an effect, at this moment in time, it is a question of having to re-think accepted theories.”

 The Evolution of the “Fish Lizards” Shows that Something “Fishy” may Have Been Going On

The "Missing" Ichthyosaurus Model

The "Missing" Ichthyosaurus Model

Picture Credit: Everything Dinosaur

As other areas of the Middle East are explored, perhaps more marine reptile fossils will be found and further evidence for the radiation and the eventual extinction of the Ichthyosauria will come to light.

15 05, 2013

We Could Have the Smile of a Crocodile

By | May 15th, 2013|Animal News Stories|0 Comments

Stem Cell Study of Alligators Provides Clues to Tooth Regeneration in Humans

A team of international researchers led by scientists at the University of California have been getting their teeth into the problem of tooth renewal in humans.  Their study of the toothsome American Alligator (Alligator mississippiensis), a reptile famed for its powerful bite may lead to the demise of certain aspects of dentistry, if a tooth is lost why not simply grow a replacement?

Could Alligators Hold the Key to Human Tooth Renewal?

Could Alligators give us all "crocodile smiles"?

Could Alligators give us all "crocodile smiles"?

One of the fascinating aspects of the Archosauria, that’s animals such as the dinosaurs and some of today’s living Archosaurs the Crocodilians, is these creatures’ ability to replace teeth that are lost throughout their adult lives. Reptiles and fish have the ability to regenerate teeth if they are lost.  For example, a Great White Shark (Carcharodon carcharias), has the ability to replace teeth that are lost.  Dinosaurs are sometimes referred to as “land sharks”, because they too, had this impressive ability.  Good news for both the sharks and the Tyrannosaurids for example.  After all, if T. rex lost teeth either fighting or feeding then being toothless would have been a very serious and fatal drawback.  Nobody is going to watch “Jurassic Park” to see a fourteen metre long apex predator lick its victims to death.

Fish and reptiles have the ability to regenerate teeth that have been lost, mammals on the other hand have much more limited dental options.  Humans for example, can renew their dentition just once, (milk teeth replaced by adult teeth).  In essence, our species has just two sets of teeth for a lifetime (diphyodont dentition).  However, new research involving the microscopic study of the structure of Alligator teeth could help scientists to learn how to stimulate tooth regeneration in humans.  The research team led by pathology Professor Cheng Ming Chuong (University of Southern California), have discovered unique cellular and molecular processes which permit tooth renewal in the American Alligator.  The academic paper detailing this new research has been published in the “Proceedings of the National Academy of Sciences”.

One of the Lead Members of the Research Team Professor Cheng Ming Chuong

Lead author of the scientific paper Professor Chuong

Lead author of the scientific paper Professor Chuong

Picture Credit: University of Southern California

Professor Chuong commented:

“Humans naturally only have two sets of teeth — baby teeth and adult teeth.  Ultimately, we want to identify stem cells that can be used as a resource to stimulate tooth renewal in adult humans who have lost teeth.  But, to do that, we must first understand how they renew in other animals and why they stop in people.”

Mammals evolved from reptiles, our species shares a common ancestor with the American Alligator.  We may look very different from the scaly crocodiles with their impressive teeth, but there remain similarities.  For example, like the Alligator, our teeth are implanted in sockets in the dental bone.  In the human jaw there is the lingering presence of a band of epithelial tissue referred to as the dental lamina.  This same type of epithelial tissue was found to be present within the components that make up each tooth of an Alligator.  Epithelium tissue is one of four types of tissue found in the higher Animalia (muscle, connective, epithelium and nerve tissue).  This band of epithelial tissue is crucial to tooth development and growth, the research team reasoned that because Crocodilians have well organised teeth with a similar form and structure to our own, their dentition would make a suitable model for studying the process of tooth replacement with the objective of finding ways in which humans could grow replacement teeth.

Some Structures and Components of Crocodilian Dentition are Similar to Mammalian Dentition

Scientists research the dentition of Crocodilians.

Scientists research the dentition of Crocodilians.

Assistant Professor of Pathology at the Keck School of Medicine Ping Wu, stated:

 “They [Alligators] have eighty teeth, each of which can be replaced up to fifty times over their lifetime, making them the ideal model for comparison to human teeth.”

Under microscopic investigation, the authors of the scientific paper found that each separate Alligator tooth is actually a complex “family” of three tooth components, the functional teeth in the jaw, a replacement tooth ready to erupt to replace the tooth if and when it is lost and the dental lamina.  In essence, each tooth has components at different stages of development, tooth replacement is essentially a “conveyor belt operation”, as one member of the Everything Dinosaur team commented.  There is a smooth transition from the loss of a mature tooth to its replacement and the dental laminae seems to hold the key to this process.

Microscopic Analysis of Alligator Teeth Reveal Complex “Family of Components”

Research into Alligator tooth regeneration.

Research into Alligator tooth regeneration.

Picture Credit: University of Southern California – Health Sciences

University of Southern California researchers identified three developmental phases for each alligator tooth unit, comprising a functional tooth (f), replacement tooth (r) and dental lamina.  The two-headed arrow provides orientation in the mouth, the buccal direction is towards the cheek, the lingual direction is towards the tongue.

The research team have concluded that the Alligator dental laminae contains what appear to be stem cells from which new replacement teeth develop.

Co-author of the study, Associate Professor Randall B. Widelitz explained:

“Stem cells divide more slowly than other cells.  “The cells in the Alligator’s dental lamina behaved like we would expect stem cells to behave.  In the future, we hope to isolate those cells from the dental lamina to see whether we can use them to regenerate teeth in the lab.”

The researchers went onto demonstrate that tooth growth is speeded up by novel cellular mechanisms in response to unexpected, premature tooth loss.  Although, growing human teeth to replace adult teeth lost in trauma or as a result of disease is a long way off, the authors of this paper hope to apply the principles of Alligator tooth renewal to regenerative medicine in the future.

Perhaps dentures will be redundant in the future, we will all have “crocodile smiles” instead.

14 05, 2013

Let’s Hear it for Our Hominid Ancestors

By | May 14th, 2013|Dinosaur and Prehistoric Animal News Stories|0 Comments

New Study into Fossilised Ear Bones Provides Information on the Evolution of Hearing in Early Hominids

The three bones that comprise the auditory ossicles (the bones of the middle ear that transmit sound vibrations to the cochlea), may the the smallest bones in the human body but they are having a big impact on the way in which anthropologists view the evolution of hearing in early hominids.

The term ossicles, means tiny bones, and this term is used to describe the malleus (hammer), incus (anvil) and the stapes (stirrup) bones, the three bones that make up the auditory ossicles, although in anatomy and other sciences such as palaeontology, ossicles can refer to any small bone.  A team of international researchers led by scientists from the Department of Anthropology at Binghamton University (New York, United States), have been able to compare and contrast the fossilised middle ear bones of a Paranthropus robustus to other fossil specimens such as additional ear ossicles from Australopithecus africanus.  The team’s findings suggest that the malleus (hammer) may not have changed much over millions of years but anatomical differences in the specimens of the other ear bones, the incus and the stapes, in conjunction with other morphological differences suggest that we modern humans, hear very differently than our ancient hominid cousins.  The research team conclude that modern humans (H. sapiens) have a different range of auditory capacities than these early hominid taxa.

The Oldest Hominid Auditory Ossicles in the Fossil Record to Date

Shedding light on the evolution of human hearing.

Shedding light on the evolution of human hearing.

Picture Credit: Texas A&M

The picture above shows the three middle ear bones of P. robustus, the stapes, the incus and the malleus.

The Anthropology Department at Binghamton University houses an extensive range of fossil casts of early hominids.  However, fossils of the auditory ossicles are only rarely preserved, their size and delicate nature often precludes them from any fossil preservation process.

The American team, assisted by colleagues from Italy and Spain examined a range of middle ear fossils, including a complete ossicular chain (malleus, incus and stapes) from a single individual specimen of Paranthropus robustus.  The fossils used in this study, including those from the P. robustus were discovered in the cave sites of Swartkrans and Sterkfontein in South Africa.  The dolomitic limestone that dominates the landscape of these areas is dotted with a large number of caves and many fossils of Late Pliocene hominids have been found.  These locations have been afforded UNESCO World Heritage Site status, such is their importance to palaeoanthropology.

Binghamton University anthropologist Rolf Quam and his colleagues were very keen to examine the middle ear bones unlike the vast majority of the  other 203 bones that make up a H. sapiens skeleton the auditory ossicles are fully formed at birth.    Babies and infants have technically more bones in their bodies than adults.  As we grow so these bones fuse together to give the 206 bones that are found in most human skeletons.  This means that any hominid fossilised auditory ossicles found would preserve the shape that they have always had, there would be no distortion in the data obtained from any study due to making allowances for fusing and growing of the bones when the individual was alive.  As the international team of researchers stated, the unchanging size and shape of the auditory ossicles suggest that these bones could harbour a wealth of evolutionary data, perhaps even providing an aid to scientists as they attempt to define more accurately our own evolutionary relationships with other hominids.

Comparing the Auditory Ossicles of Early Hominids

Comparing the malleus of P. robustus (top) to A. africanus (bottom)

Comparing the malleus of P. robustus (top) to A. africanus (bottom)

Picture Credit: R. Quam/PNAS

The research team noticed that the malleus (hammer) bone in the ancient hominids studied is very human-like.  It is very different in size and shape when it is compared to the malleus of extant apes such as gorillas.  The skull, teeth and jawbone of P. robustus for example, may be very ape-like, but the malleus is very similar to our own.  As Paranthropus robustus is believed to have represented a hominid sub-branch that did not lead directly to more advanced hominids such as Homo ergaster, Homo neanderthalensis and ultimately our own species, this research suggests that the shape and size of the malleus must have a very deep phylogenetic origin.  In other words, this trait could be traced back to a common ape/human ancestor deep into the Pliocene Epoch.

The incus (anvil) and the stapes (stirrup) in contrast, are much more ape-like.  This means that the auditory ossicles of ancient hominids show a combination of human and ape characteristics.   The research paper, published in the prestigious journal “The Proceedings of the National Academy of Sciences”, leads to an intriguing conclusion. If the shape of the auditory ossicles of ancient hominids were different from our own, then their hearing abilities are likely to have been different too.  This study lends support to the theory that these ancient hominids were not capable of producing speech as we do.   Certainly, they could communicate but based on the shape of their ear bones, these ancient human-like creatures may have struggled to pick up the range of acoustic frequencies that we use in everyday conversation.

Chimpanzees struggle to pick up the frequency of human speech, the evolution of the incus and the stapes could perhaps provide evidence of the development of human communication within the fossil record.  However, the paucity of the known fossil material rather excludes this possibility for the moment.

Commenting on the research, Assistant Professor Rolf Quam stated:

“Bipedalism [walking on two feet] and a reduction in the size of the canine teeth have long been held up as the “hallmark of humanity” since they seem to be present in the earliest human fossils recovered to date.  Our study suggests that the list may need to be updated to include changes in the malleus as well.  More fossils from even earlier time periods are needed to corroborate this assertion.”

13 05, 2013

Fossil Experts Demonstrating their Skills at Lyme Regis Museum

By | May 13th, 2013|Educational Activities, Everything Dinosaur News and Updates, Press Releases|0 Comments

Fossil Polishing Demonstration at Museum

Members of the public have the opportunity to take part in fossil polishing and learn the skills of fossil preparation next weekend (18th and 19th May), as experts will be demonstrating their skills and knowledge at the Lyme Regis Museum (Dorset, southern England).

If you have ever wondered how Ammonite fossils are prepared so that all the exquisite details of their internal structures are revealed, then pop down to the Lyme Regis Museum next weekend and meet up with renowned fossil experts Brandon Lennon and Chris Andrew who will be demonstrating how Ammonite fossils should be polished.  The fossil polishing team, recently attended the Lyme Regis Fossil Festival and over the course of the three day event they managed to prepare and polish in excess of 700 Ammonite specimens.  For a small fee, members of the public can have a go at preparing their very own Jurassic specimen and if they are lucky they will be able to purchase part of the amazing legacy of the famous Jurassic coast.

Brandon and Chris Being Kept Very Busy at the Recent Fossil Festival

Brandon Lennon (background) and Chris Andrew (foreground) working with Ammonites.

Brandon Lennon (background) and Chris Andrew (foreground) working with Ammonites.

Picture Credit: Brandon Lennon

Lyme Regis fossil expert Brandon commented:

“Sometimes members of the public are surprised that there are still fossils to be found, after all, fossils have been collected from this part of the Dorset coast for more than two hundred years.  The reason that we keep discovering fossils along this part of the Jurassic coast is because the cliffs are constantly eroding.  Storms and high tides keep revealing fossils”.

Ammonites and their relatives the Goniatites are an extinct group of cephalopods (Molluscs) related to today’s squid and cuttlefish.  Ammonite shells were made of aragonite (a form of calcium carbonate).  They were abundant in the shallow seas of the Mesozoic and diversified into a huge range of different species.  Ammonites are an important group of fossils and help scientists to age rock strata due to their biostratigraphic distribution.

The fossil preparation demonstrations start at 10am and run through to 4pm on Saturday and Sunday (18th and 19th May) and all are welcome to take part in real “hands-on” science.

A spokesperson from Everything Dinosaur stated:

“This is a rare opportunity to pick the brains of local fossil experts in the Lyme Regis area and to learn some of the skills of fossil preparation and fossil identification.”

After a number of recent rock falls, there should be plenty of specimens available, although members of the public are advised to heed the advice of the local authorities when walking close to the cliffs or indeed taking any of the coastal paths.  Many of the cliffs remain unstable and the threat of landslides and rock falls requires visitors to this part of the south coast to take care.

To get the best out of a visit to the Lyme Regis or Charmouth areas Everything Dinosaur recommends taking a guided tour of the beaches with a local fossil expert.

For more information about guided fossil walks: Guided Fossil Walks

12 05, 2013

When is a Euoplocephalus a Euoplocephalus?

By | May 12th, 2013|Dinosaur Fans, Palaeontological articles|0 Comments

Researcher Identifies That Fossils Ascribed to Euoplocephalus Actually Represent Different Species

The taxonomic classification of the Ankylosaurids just got a whole lot more complicated, or to put it another way, a University of Alberta graduate researcher has reaffirmed analysis carried out in the early part of the 20th Century that proposed more species of armoured dinosaur in North America.  It seems that fossils assigned to one species of Ankylosaur,  known as Euoplocephalus tutus may represent a total of four different species of armoured dinosaur.  Subtle differences noted by the student, originally identified by palaeontologists nearly one hundred years ago, suggest that the genera of Dyoplosaurus, Anodontosaurus and Scolosaurus may have to be resurrected.  This leads to the intriguing question of why were there so many kinds of big, armoured dinosaur and how were some species able to live alongside each other in the same habitats?

The research has just been published in the scientific publication,  “PLoS One”, the Public Library of Science.

The Ankylosaur group of dinosaurs are often referred to as “living tanks” as some members of this group of bird-hipped dinosaurs (Ornithischians) were very wide-bodied, heavily armoured and possessed clubs on the end of their tails.  As these types of Ankylosaur are known from Upper Cretaceous sediments of North America and Asia it had been suggested that their defensive armour and vicious tail clubs evolved so that these slow moving creatures could withstand attack from the massive Tyrannosaurids, which were the apex predators.  Indeed, most media images of creatures such as Ankylosaurus (A. magniventris) and the Chinese Ankylosaur Shanxia (S. tianzhenensis) depict these squat, heavy reptiles defending themselves against an attack from a Tyrannosaur by swinging their savage tail clubs.  That may be the popular image of Ankylosaurs, but the fossil record for these herbivores of the Late Cretaceous reveals that there may be a lot more to this clade of the Dinosauria, for example, one University of Alberta researcher has suggested that several different types of these giants could have lived in the same environment at the same time.

A Model of a Typical Ankylosaurid (A. magniventris)

Armoured Dinosaur - Ankylosaurus

Armoured Dinosaur - Ankylosaurus

Picture Credit: Everything Dinosaur

The Ankylosaurs and the Stegosaurs are grouped together into a sub-group of the Ornithischia known as Thyreophorans (shield bearers).  These dinosaurs are characterised by the presence of armour plates on the top and along the sides of their bodies.  Late Cretaceous Ankylosaurs like the eleven metre long A. magniventris had huge plates of armour on the neck and shoulders, with smaller plates running in rows along the flanks.  The tail, stiffened by fused bony tendons posessed a massive, bony club on the end, in essence modified caudal vertebrae.

It was Franz Nopsca, back in 1915 who first suggested that these types of dinosaurs be classified into a sub-group, the Thyreophora, although he included the horned dinosaurs (Ceratopsians) as well.  Between 1900 and the  early 1930s there was an extensive programme of dinosaur classification undertaken, partly due to the large number of new dinosaur fossils, including armoured dinosaurs being discovered in Canada and the western United States.  A number of new Ankylosaurid species were established most based on fragmentary fossils such as individual skull specimens and vertebrae.

Euoplocephalus (E. tutus) , a species named by Lawrence Lambe in 1902 was an exception.  This dinosaur is represented by a very much larger number of fossils than most other types of Ankylosaurid.  It is also unusual as fossils ascribed to Euoplocephalus have been found in the Dinosaur Park, Horseshoe Canyon and Two Medicine Formations.  These Formations represent several million years of worth of geological deposits and this implies that the Ankylosaur known as Euoplocephalus existed as a species for a very long time.  Earlier studies from the 20th Century assigned a number of genera to the fossils, dinosaur genera such as Scolosaurus (Scolosaurus cutleri), Anodontosaurus (A. lambe) and Dyoplosaurus (D. acutosquameus) were established.

Following a review in the 1970s, all these types of Ankylosaur were reclassified as belonging to the Euoplocephalus genus.  However, University of Alberta researcher, Victoria Arbour undertook a comprehensive review of the fossil material and her study suggests the 20th Century scientists may have been right all along.  She visited museum collections in North America and Europe and carefully examined small variations in the configuration of the skull armour and the bony tail clubs.  Her analysis suggests that the fossils grouped together under the Euoplocephalus genus do actually constitute four individual species of dinosaur.

Arbour explained that:

“In the 1970s the earlier work was discarded and those four species were lumped into one called species Euoplocephalus.  I examined many fossils and found I could group some fossils together because their skull armour corresponded with a particular shape of their tail club.”

Simplified Explanation of Differences between the Four Ankylosaurids

Simplified comparison table.

Simplified comparison table.

Table Credit: Everything Dinosaur

The four species span a period of geological time of around ten million years from the Late Campanian faunal stage of the Cretaceous into the Maastrichtian and her research shows that the Dinosaur Provincial Park Formation had three different types of armoured Ankylosaurid dinosaur living in that region of Alberta at the same time.   Her work suggests that Scolosaurus, Dyoplosaurus and Euoplocephalus shared the same environment, if these very similar creatures lived in the same habitat it begs several questions such as how were the food resources divided up?  How did all three species manage to survive?  How much interspecific competition would there have been?

Stratigraphic Distribution of Campanian-Maastrichtian Ankylosaurids in the Study

Stratigraphic distribution of Campanian-Maastrichtian Ankylosaurid species.

Stratigraphic distribution of Campanian-Maastrichtian Ankylosaurid species.

Table Credit: Journal PLoS One

Previously, Victoria had examined Ankylosaur tail clubs with a view to understanding how they might have been used as defensive weapons, to read an article about her earlier research: Ankylosaurs had a Smashing Time

This also has implications for the fossil material that remains ascribed to Euoplocephalus.  The re-division of the Euoplocephalus fossil material into four species means that there was not the degree of individual variation in the Euoplocephalus tutus species as once thought.

Skulls of Ankylosaurids Compared (Dorsal View – looking at the tops of the skull)

Dorsal view of Ankylosaurid skull material used in study.

Dorsal view of Ankylosaurid skull material used in study.

Picture Credit: Journal PLoS One

There has been much debate between palaeontologists as to how to distinguish A. magniventris fossil material with that ascribed to E. tutus. The re-classification of a significant portion of the Euoplocephlus material to other species may muddy the waters somewhat further.  Although, E. tutus material is still substantial and it remains one of the more complete Ankylosaurid genera in terms of the number of fossils known, Arbour’s research now leaves no specimen of Euoplocephalus that includes bony armour “in situ” in relation to other skeletal material.  In short, the arrangement of the armour (osteoderms) on Euoplocephalus is now very much open to question.

Ornamentation Patterns on the Tops of Ankylosaurid Skulls Compared

Cranial ornamentation in Ankylosaurids compared.

Cranial ornamentation in Ankylosaurids compared.

Picture Credit: Journal PLoS One

The picture above shows a number of the skulls that were analysed in the study (dorsal view, viewed from the top).  The skull marked as CMN 0210 is the holotype for Euoplocephalus tutus (top left), CMN 8530 is the holotype material associated with Anodontosaurus lambei (bottom row on left) and ROM 784 is the holotype for Dyoplosaurus acutosquameus, adjacent to the Euoplocephalus holotype.

It seems there is a lot more to learn about when it comes to these heavily armoured dinosaurs commonly referred to as “living tanks”.

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