A fabulous pair of eurypterid fossils photographed in the London Natural History Museum.
Spotted in the British Museum (London), two beautifully preserved sea scorpion fossils. The picture (below) shows a wonderful example of what looks like a fossilised, giant woodlice. However, all is not as it seems.
Sea Scorpion Fossil Specimens
A pair of eurypterid fossil specimens on display at the London Natural History Museum. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Woodlice are isopods and members of the Arthropoda Phylum. Eurypterids are arthropods too. Both have segmented bodies and share several anatomical characteristics, but they are only distantly related.
Probably originating during the Ordovician, eurypterids persisted until the Permian. Both marine and freshwater forms evolved. Some marine eurypterids represent the largest arthropods known to science. The largest described to date is Jaekelopterus rhenaniae. Based on a forty-six-centimetre claw fossil, palaeontologists have suggested that J. rhenaniae reached a length of 2.5 metres or more.
Although the eurypterid fossils on display are not as large as the biggest species of Jaekelopterus (pronounced Yay-kel-op-ter-us), they are still impressive.
A spokesperson from Everything Dinosaur commented on the details preserved within the fossil specimens and stated:
“When you see up close stunning eurypterid fossils, you gain an appreciation of the diversity and variety of life on Earth. It is hard to believe, but for more than 150 million years these amazing arthropods thrived, outcompeting vertebrates. Many forms evolved to become apex predators.”
A team of international scientists writing in the academic publication “The Journal of South American Earth Sciences”, have reported the discovery of the first pterosaur fossils known from Uruguay. The fossil material representing a fragment of jaw with associated teeth, is believed to represent a new species of Ctenochasmatidae pterosaur. Ctenochasmatids are geographically widespread with fossils reported from the United States, China, southern Germany, Argentina and England. The fossils ascribed to this family of short-tailed pterosaurs have a large temporal range, from the Late Jurassic transitioning through to the Early Cretaceous.
Views of the Fragmentary Fossil Material (Rostrum)
The first pterosaur fossils from Uruguay.
Picture credit: The Journal of South American Earth Sciences
Buck-Toothed Pterosaur
The fossil comes from the Tacuarembó Formation, which is believed to represent deposits laid down as the early Atlantic Ocean opened up. The strata largely consists of sediments deposited in a terrestrial, near-shore environment. The orientation of the tooth sockets and the preserved tooth base suggests that the conical teeth were pointed out sideways and forwards. This may have been an adaptation for capturing slippery prey such as small fish. This family of small pterosaurs exhibit a variety of different shaped mandibles, although fragmentary, the researchers have identified that the fossil jaw widens towards the tip (anterior portion), the shape of the jaw and its size corresponds to jaws of known ctenochasmatids, specifically the subfamily Gnathosaurinae.
Different Jaw Types within the Ctenochasmatidae
Ctenochasmatid mandibles.
Picture credit: Wellnhofer, Howse et al from Witton
The picture shows mandible variation within the Ctenochasmatidae (A) Ctenochasma elegans seen from below, (B) Plataleorhynchus streptorophodon as viewed from below and (C), the skull of Gnathosaurus subulatus (viewed from underneath). The dentition and the shape of the mandibles suggest adaptations for catching and consuming different types of prey.
Dating the Geological Formation Thanks to a Shark
The Tacuarembó Formation has proved very difficult to date, as the fossils found in the strata were not that easy to compare to fossils found in other rocks. Despite, an abundance of bone fragments representing a range of creatures, including theropod dinosaurs, the Tacuarembó Formation lacked helpful biostratigraphic indicator fossils to assist with relative dating. This changed with the discovery of numerous teeth and a single dorsal spine which was assigned to the Hybodont shark Priohybodus arambourgui.
Fossils of this primitive shark are known from the Arabian Peninsula as well as Africa and the strata associated with these fossils has permitted more accurate dating to occur. Thanks to this shark, the authors of this new paper can state that the pterosaur fossil material comes from a fossiliferous horizon no older than the Late Jurassic. As such, the Uruguayan pterosaur remains represent the oldest ctenochasmatid found in South America known to science.
Team members at Everything Dinosaur, took the opportunity whilst in London last week to pay a visit to the Grant’s Museum of Zoology, this hidden gem of a museum contains around 68,000 specimens and the densely packed cabinets house an absolute treasure trove of zoological wonders. The Grant Museum of Zoology and Comparative Anatomy (to give this establishment its full title), is part of the University College London, it plays an important role in helping to teach students about anatomy. It was founded by Robert Edmond Grant (1793-1874).
The Grant Museum
The Grant Museum of Zoology and Comparative Anatomy was established in 1827 to serve as a teaching collection at the newly founded University of London (later University College London). The influential Grant taught the young Charles Darwin and he was the first Professor of Zoology and Comparative Anatomy in England. A lack of teaching resources did not deter the enthusiastic scientist, he set about amassing an astonishing collection of specimens, diagrams, dissection materials and lecture notes, it is these that form the basis of the Museum today.
Saying Hello to “Proavis”
Tucked up high on a shelf, barely given a second glance by the casual visitor, is a rather strange animal. This is “Proavis”, otherwise known as Pro-Aves. It is not an anatomical specimen as such, it is not the preserved remains of a living animal, rather it a model that attempts to depict the ancestor of birds (Aves) and as such, it is extremely significant.
Saying Hello to Proavis – (Pro-Aves)
The “Proavis” model at the Grant Museum of Zoology (London).
Picture credit: Everything Dinosaur
The rather strange looking creature is a little worse for wear, after all, it is over a hundred years old. Proavis consists of a wire armature, which has been covered in wax and real feathers. It represents a theoretical missing link between feathered, maniraptoran dinosaurs and the first birds, such as Archaeopteryx (A. lithographica). During the late 19th century, leading academics began to realise that birds may be closely related to dinosaurs. Such ideas were fuelled by the publication of the seminal work “The Origin of Species” by one of Professor Grant’s former pupils (Charles Darwin) in 1859 and the excavation of the first, very nearly complete fossil of Archaeopteryx in 1861.
A Model of the Hypothetical “Missing Link” Between Reptiles and Birds
A model of the hypothetical animal Proavis.
Picture credit: Grant Museum of Zoology
A Model of a “Missing Link”
The model is based on an illustration of a “missing link” a hypothetical transitional form between the reptiles and birds. The term “Proavis” was first coined in 1906 by the English zoologist William Plane Pycraft. Pycraft wrote a number of books on evolution and natural history including “The Story of Reptile Life”, that was published in 1905. He believed that flight in early birds developed from ancestral forms that glided between trees, the “tree down” view. However, other academics at the time proposed alternative theories for the evolution of the birds. For example, the Hungarian polymath Franz Nopcsa proposed that flight developed first amongst fast-running terrestrial reptiles, which used their flapping arms to run faster.
The feather and wax model in the Museum originally came from Cambridge. It was probably made by a student and it reflects the “ground up” view as championed by the likes of Nopcsa.
An Illustration of a Transitional Form Between Reptiles and Birds “Tree Down” Concept
From the “Origin of Birds” by Gerhard Heilmann.
Picture credit: Gerhard Heilmann
A Delicate and Fragile Model at the Grant Museum
This delicate and fragile model may look very different from today’s interpretations of the first birds and the maniraptoran dinosaurs from which birds are descended, but it does represent an important milestone in academic thinking. Models like “Proavis” were used to explore evolutionary theories from more than a century ago. As such, it does represent a “transitional form”, epitomising how ideas about tetrapods have changed over time.
A More Modern Interpretation of a Reptile that was Ancestral to Aves (Dromaeosauridae)
An illustration of the dromaeosaurid Adasaurus (A. mongoliensis).
Picture credit: Everything Dinosaur
The image (above) depicts a dromaeosaurid (Adasaurus). It is based on a dromaeosaurid figure from the recently introduced Beasts of the Mesozoic model range: Beasts of the Mesozoic Models.
New Research Challenges Traditional View of Pterosaur Flight
Take a look at a picture of a pterosaur flying and you will see that most illustrations and life-reconstructions of these reptiles depict them travelling through the air with their hind limbs trailing behind them and their back legs wide apart. However, a new study undertaken by scientists from Brown University (Rhode Island) and the University of California (Berkeley), suggests that we have got this all wrong, pterosaur joints did not permit them to fly with their hind limbs splayed far apart.
Pterosaurs in the Air – But Have we got Their Hind Limbs in the Wrong Position?
Six new species of pterosaur have been recently identified from Moroccan fossils but if we depict them flying, the convention is to show the hind limbs spread far apart.
Picture credit: John Conway
We Look at the Bones, But What About the Ligaments?
Flying with the hind limbs splayed out, is a posture adopted by most bats when they take to the air. Ever since the first flying reptiles were described and illustrated, these archosaurs have been depicted in the same way. However, this new research, published in the Proceedings of the Royal Society B (biology), suggests that ligaments would restrict joint movement and pterosaurs and the volant dinosaurs such as Microraptor, could not have flown in the same way as bats.
Lead author of this study, Armita Manafzadeh, a PhD student at Brown University commented:
“Most of the work that’s being done right now to understand pterosaur flight relies on the assumption that their hips could get into a bat-like pose. We think future studies should take into account that this pose was likely impossible, which might change our perspective when we consider the evolution of flight in pterosaurs and dinosaurs.”
The “Classical” Pterosaur Flying Posture
The “bat-like” posture of the hind limbs of pterosaurs, may not have been anatomically possible.
Picture credit: Armita Manafzadeh
The study undertaken in collaboration with Kevin Padian (University of California), attempted to infer the range of motion of joints in a way that takes into account the soft tissues such as ligaments surrounding the joint. Usually, soft tissue such as ligament and cartilage does not fossilise, so palaeontologists have to work out joint motion from just the bones alone. The pair of scientists set out to examine the joint movement of modern dinosaurs – birds, to test the extent to which ligaments influence joint motion.
Chickens at a Grocery Store
Student Manafzadeh explained that the idea started with grocery store chickens:
“If you pick up a raw chicken at the grocery store and move its joints, you’ll reach a point where you will hear a pop. That’s the ligaments snapping, but if I handed you a chicken skeleton without the ligaments, you might think that its joints could do all kinds of crazy things, So, the question is, if you were to dig up a fossil chicken, how would you think its joints could move and how wrong would you be?”
Quetzalcoatlus – A Giant Pterosaur Takes to the Air (Note the Splayed Out Back Legs)
Quetzalcoatlus takes to the air.
Picture credit: Everything Dinosaur
Dead Quails and X-ray Images
Chickens may be easy to acquire, but for this scientific study, dead quails were used in order to assess joint mobility in a three-dimensional way, rather than just referring to the bones. Birds are the closest living relatives to the extinct pterosaurs and the non-avian dinosaurs. Birds (Aves), the Pterosauria and the Dinosauria are members of the Archosauria clade. This clade is usually divided into two distinct branches, on one branch (Crurotarsi), are the crocodilians and their ancestors plus several other extinct lineages such as the phytosaurs. The second branch (Avemetatarsalia) groups all the reptiles more closely related to birds than crocodilians.
A sub-group of the Avemetatarsalia is the Ornithodira, which specifically nests the Pterosauria and their ancestors and the Dinosauria and their ancestors, plus the descendants of dinosaurs – birds, together. Hence, the use of quail limbs to assess the range of movement and joint mobility.
The skin and muscle surrounding the joints was cut away and once the hip joints were exposed, the scientists manipulated them taking X-ray images to assess the likely range of motion. By doing this, they could determine the exact positions of the bones in poses where the ligaments restricted and then prevented further joint movement.
Mapping Out the Joint Movements of Ornithodirans
This technique enabled Manafzadeh to map out the range of motion of the quail hip with ligaments attached. She then compared this range of motion to what was inferred when the bones were considered in isolation. For the bones-only poses, Manafzadeh used traditional criteria that palaeontologists often employ — stopping where the two bones hit each other and when the movement pulled the thigh bone out of its socket.
This experiment revealed that over 95 percent of the joint positions that seemed plausible with bones alone were actually impossible when the ligaments were attached.
Mapping Out the Range of Motion in Quail Hips
Mapping the range of movement in quail hind limbs to assess the movement of ornithodiran limbs.
Picture credit: Armita Manafzadeh
The Implications for Pterosaurs and the Maniraptora
The team’s next move was to calculate how the range of motion in living birds might correlate to the range of motion expected for extinct pterosaurs and those members of the Maniraptora, such as Microraptor that are believed to have been able to fly. The assumption has long been that these creatures flew in a similar way to bats. That is partly because the wings of pterosaurs were made of skin and supported by an elongated fourth finger, which is superficially similar to the wings of bats. Bat wings are also connected to their hind limbs, which they splay out widely during flight.
Many palaeontologists, Manafzadeh says, assume pterosaurs and four-winged dinosaurs did the same. But this new study suggests that pose was impossible.
In quail, a bat-like hip pose seemed possible based on bones alone, but outward motion of the thigh bone was inhibited by one particular ligament, a ligament that’s present in a wide variety of birds and other reptiles related to the Pterosauria. Consequently, in the absence of extraordinary evidence to the contrary, this analysis casts doubt on the “bat-like” hip pose traditionally inferred for pterosaurs and basal maniraptorans and underscores the point that reconstructions of joint mobility based on manipulations of bones alone can be misleading.
To achieve a “bat-like” flying posture, the ligament would have to stretch 63 percent more than the quail ligament can, the implication is that we have been illustrating flying reptiles and flying dinosaurs all wrong.
A Model of a Volant Dinosaur (Microraptor)
The PNSO Gaoyuan the Microraptor model.
The image (above) shows a beautiful Microraptor model from PNSO.
In addition to challenging traditional views about flight in pterosaurs and early birds, the research also provides new ways of assessing joint mobility for any joint of any extinct species by looking at its living relatives.
The scientific paper: “ROM Mapping of Ligamentous Constraints on Avian Hip Mobility: Implications for Extinct Ornithodirans” by Armita R. Manafzadeh, Kevin Padian published in the Proceedings of the Royal Society B
Everything Dinosaur acknowledges the assistance of a press release from Brown University in the compilation of this article.
A team of international scientists led by researchers from University College Cork (Ireland), have discovered the fossilised remains of skin flakes from feathered dinosaurs and primitive birds that lived during the Early Cretaceous. The fossil flakes of skin, preserved amongst the plumage of the feathered creatures, has provided evidence on how dinosaurs shed their skin. Unlike many reptiles alive today, animals such as lizards and snakes, which shed their skin as a single piece or as several large pieces, it seems that basal birds and non-avian dinosaurs shed small epidermal flakes just like modern birds and mammals and that includes us with our dandruff.
Preserved Soft Tissue Evidence – Flakes of Skin in Maniraptoran Dinosaurs and the Basal Bird Confuciusornis
Phosphatised soft tissues in non-avian maniraptoran dinosaurs and a basal bird.
Picture credit: Nature Communications
Fossil Flakes
The photographs above (labelled a to h), show scanning electron microscope generated images of tissue in the Early Cretaceous Aves C. sanctus (a,e and f), the dromaeosaurid Sinornithosaurus (S. millenii) in photographs c and h, along with the therizinosaur Beipiaosaurus (B. inexpectus), photos b and g. The photograph labelled d, is a view of epidermal flakes preserved in association with the fossilised remains of Microraptor, which along with Sinornithosaurus is believed to have been capable of flight or at least gliding.
Studying the constituents of flakes of dinosaur skin, which come from animals that might have been volant, is very important. Palaeontologists can compare these flakes to living birds which are capable of powered flight. These flakes, in turn can be examined in relation to the flakes of terrestrial feathered dinosaurs such as Beipiaosaurus. Any differences in the composition of these flakes might provide scientists with further information on the aerial abilities of dinosaurs such as Microraptor and Sinornithosaurus.
An International Team
The scientists include researchers from the Chinese Institute of Vertebrate Palaeontology and Palaeoanthropology, Bristol University, Linyi University (China), the Open University as well as Queen Mary University (London) and the University College Dublin (Ireland). They studied the fossil cells and dandruff from a range of Early Cretaceous Theropods and compared the skin flakes to those of living, extant birds.
Lead author of the research, Dr Maria McNamara (University College Cork), stated:
“The fossil cells are preserved with incredible detail, right down to the level of nanoscale keratin fibrils. What’s remarkable is that the fossil dandruff is almost identical to that in modern birds – even the spiral twisting of individual fibres is still visible.”
Getting to Grips with Corneocytes
The scientists used a scanning electron microscope (SEM), to examine the beautifully preserved, but microscopic fossilised fragments of skin associated with three feathered dinosaur specimens (Microraptor, Beipiaosaurus and Sinornithosaurus) and one Early Cretaceous bird Confuciusornis (Confuciusornis sanctus). All of these fossils are associated with the Jehol biota of north-eastern China.
A Pair of Fossilised Confuciusornis (Liaoning Province) Showing the Two Known Body Plans for these Ancient Birds
A pair of Confuciusornis fossil birds (Liaoning Province).
Just like our own flakes of skin, our dandruff, the fossil flakes consist of tough cells known as corneocytes. These cells are full of protein fibres (keratin), such was the quality of preservation that the SEM analysis was able to identify bundles of these fibres and even to hone in on single strands.
Scanning Electron Micrographs of Skin Flakes Associated with C. sanctus
Ultrastructure of the soft tissues in Confuciusornis.
Picture credit: Nature Communications
The photographs (above) show highly magnified images of the skin flakes associated with Confuciusornis. Closely packed polygons can be observed (a and b), whereas (c) shows a detailed view of the polygons and the first signs at this magnification of the bundles of fibrous keratin. The drawing (d) interprets the bundles as more darkly shaded areas in the central part of each polygon. Photograph (e) shows the area that was more closely observed (f and g) indicating the presence of fibres, whereas, (h) shows the fibrous bundle associated with a skin flake in an extreme close-up view.
Helical coiling of the tiny fibres is shown (picture i) and photographs j and k show polygons having been deformed by some form of stretching.
These structures were then compared to the flakes of skin associated with living birds, in this case, male specimens of Zebra Finches (Taeniopygia guttata) and the Java Sparrow (Lonchura oryzivora). In addition, the fossil evidence was compared to the moulted, downy feathers of a male American Pekin Duck (Anas platyrhynchos domestica).
Fossil Flakes Provide Clues About Dinosaur Metabolism
This research suggests that this ability to constantly shed skin evolved sometime in the late Middle Jurassic, around the same time as a host of other skin features evolved. The feathered epidermis of dinosaurs acquired many, but not all, anatomically modern attributes close to the base of the Maniraptora clade.
Dr McNamara explained:
“There was a burst of evolution of feathered dinosaurs and birds at this time, and it’s exciting to see evidence that the skin of early birds and dinosaurs was evolving rapidly in response to bearing feathers.”
Co-author, Professor Mike Benton (Bristol University), commented:
“It’s unusual to be able to study the skin of a dinosaur, and the fact this is dandruff proves the dinosaur was not shedding its whole skin like a modern lizard or snake but losing skin fragments from between its feathers.”
Corneocytes in Living Birds
Corneocytes in extant birds.
Picture credit: Nature Communications
The four photographs above, show scanning electron micrographs of shed skin flakes in living birds. Note the polygonal structure (a), which is reminiscent of the shapes seen when the corneocytes of extinct dinosaurs and birds were studied. Photograph (b) shows a central depression in the cell associated with a pycnotic nucleus, whilst photographs (c and d) show skin flakes stuck to the bird’s feathers.
Modern birds have very fatty corneocytes with loosely packed keratin, which allows them to cool down quickly when they are flying for extended periods. The corneocytes in the fossil dinosaurs and birds, however, were packed with tightly bundled keratin, suggesting that the extinct creatures didn’t get as warm as modern birds, presumably because they couldn’t fly at all or for as long.
This suggests that Confuciusornis did not fly that well, if probably flew in short bursts, but may not have been capable of making prolonged flights. The lack of fatty corneocytes in those dinosaurs which are thought to have had some aerial ability (Microraptor and possibly Sinornithosaurus), sheds doubt on whether they were truly volant.
Could Some Dinosaurs Like Microraptor Fly?
A member of the Dromaeosauridae sub-family the Microraptorinae, but could these dinosaurs fly? The absence of fatty corneocytes suggests a lower metabolism than with extant birds..
Picture credit: Everything Dinosaur
The picture (above) shows a Microraptor model from Safari Ltd.
Everything Dinosaur acknowledges the assistance of a press release from the University College Cork (Ireland) in the compilation of this article.
The scientific paper: “Fossilised Skin Reveals Coevolution with Feathers and Metabolism in Feathered Dinosaurs and Early Birds” by Maria E. McNamara, Fucheng Zhang, Stuart L. Kearns, Patrick J. Orr, André Toulouse, Tara Foley, David W. E. Hone, Chris S. Rogers, Michael J. Benton, Diane Johnson, Xing Xu and Zhonghe Zhou published in Nature Communications.
Our thanks to young Maisy and her classmates for sending lots of beautiful dinosaur drawings to our offices. We had challenged the children (Year 2), to have a go at designing their very own prehistoric animals during a dinosaur workshop at their school. We received an amazing array of very colourful drawings, with lots of lovely labelling and some fascinating explanations from the children as to why their dinosaur was so special.
Maisy Has Designed a Maisyosaurus
A very colourful dinosaur design created by Maisy in Year 2.
Picture credit: Maisy/Everything Dinosaur
Maisy and Her Dinosaur
Maisy labelled the various body parts of her dinosaur, explaining that it was an omnivore and that it had five toes to help it cut through things. Certainly, having four fingers and a thumb makes using scissors very straight forward, I’m sure the dinosaur would have appreciated the comment. Maisyosaurus also had spikes on its back, as Maisy explained, the spikes helped this dinosaur shake off a bug should one alight on it. Perhaps it could it have shaken its big, bushy yellow tail in order to scare off flies and other insects.
Our thanks again to Maisy and the other Key Stage 1 pupils at her school for sending in the super dinosaur designs.
As team members at Everything Dinosaur make plans for the imminent arrival of the Beasts of the Mesozoic range of 1:6 scale dinosaur figures, we have been busy finalising the scale drawings of these extinct animals for use in our fact sheets. For virtually every named prehistoric animal that we supply from Achelousaurus and Acheroraptor to Zhenyuanlong, we research and write a fact sheet. In this way, our customers can learn a little about the prehistoric creature the model or soft toy represents.
A Scale Drawing of the Beasts of the Mesozoic Pyroraptor
A scale drawing of the dromaeosaurid Pyroraptor olympius.
Estimating the size of dinosaurs is quite a tricky business. When it comes to a dromaeosaur like Pyroraptor, we are hampered by the lack of fossil evidence. This dinosaur is known from a handful of teeth and some fragmentary bones. However, we estimate that this fast-running dinosaur was around 1.5 metres in size and weighed between eight and ten kilograms.
The poor fossil record of most dinosaurs hampers mass and length estimations, many of the fossils relate to sub-adults or juveniles so the exact size of an adult animal is very difficult to calculate. A case in point is the recently described Sciurumimus (Sciurumimus albersdoerferi), from Germany. This dinosaur is known from a single fossil specimen. It is a spectacular fossil and very nearly complete. However, the skeleton is that of a baby, a very young animal measuring around seventy centimetres in length.
This baby dinosaur could have grown up to become one of the largest theropod dinosaurs known from the Jurassic of Europe. Until more fossils of this species are found, the adult size of this carnivorous dinosaur remains entirely speculative.
The CollectA Sciurumimus (Sciurumimus albersdoerferi) Dinosaur Model
One of the fascinating conundrums about the end Cretaceous extinction event is how did the avian dinosaurs (birds) survive, but their very close cousins the non-avian dinosaurs, animals such as Tyrannosaurus rex, Triceratops and Edmontosaurus fail to make it through this calamitous time in Earth’s history? A team of international researchers, writing in the journal “Current Biology” have put together a fascinating explanation as to why we have birds today, but no other theropods, or indeed any other representatives of the Dinosauria.
With the extra-terrestrial impact event some 66 million and 38 thousand years ago (plus or minus 11,000 years), the ecosystems on our planet were devastated. Whether this single, huge impact was the sole cause of the mass extinction or whether this was the final “coup de grâce” is debatable, however, life would never be the same again.
Using a variety of data sources, the team, which included scientists from the University of Bath, the Denver Museum of Nature and Science, Yale University and the Field Museum amongst others, have pieced together what the impact event meant for the Aves. Their scientific paper suggests that the only kinds of birds to survive the Cretaceous-Palaeogene (K-Pg) extinction were ground- dwellers.
How Our Feathered Friends Survived the Cretaceous-Palaeogene Extinction Event
Ground-dwelling birds survived the K-Pg extinction event.
Picture credit: Phillip Krzeminski
Why Did the Birds Survive?
A number of ideas and theories have been proposed to help explain why the birds are around today, but the non-avian dinosaurs are not. Recently, Everything Dinosaur published an article on a piece of research that suggested that seed-eating may have contributed to the survival of birds during this devastating time in the history of our planet.
Commenting on the scientific paper, lead author Daniel Field of the Milner Centre for Evolution (University of Bath) stated:
“We drew on a variety of approaches to stitch this story together. We concluded that the devastation of forests in the aftermath of the asteroid impact explains why tree-dwelling birds failed to survive across this extinction event. The ancestors of modern tree-dwelling birds did not move into the trees until forests had recovered from the extinction-causing asteroid.”
The Collapse of Forests
The scientists analysed the plant fossil record and identified that the world’s woodlands and forests were virtually wiped out by the extra-terrestrial impact. Huge forest fires would have raged in the immediate aftermath of the impact and it is likely that much of the world had to endure a period of extensive “acid rain” as a result of the catastrophic event. In the months, or maybe even tens of years afterwards, our planet could have been blanketed in a cloud of dust and ash. This would have blocked out the sun and led to the collapse of food chains which relied on photosynthesising plants.
The scientists look at the record of fossil pollen and spores to assess the types of flora present and how quickly, ferns, flowering plants (angiosperms) and other types of flora recovered after the extinction event.
Plotting the Turnover of Different Types of Flora from Pollen and Spore Counts
Floral turnover evidenced by changes in relative abundance of common pollen taxa across the K-Pg boundary.
Picture credit: Current Biology with additional annotation by Everything Dinosaur.
The diagram (above), plots the palynological record of the John’s Nose Section in North Dakota, a series of sequential strata laid down before, during and after the extinction event. It helps to plot the demise of different types of plant and their recovery (floral turnover), as evidenced by changes in relative abundance of common pollen taxa across the K-Pg boundary. Note, the “fern spike” recorded not long after the extinction event, ferns are usually the first type of plant to recover from natural disasters today, as evidenced by their ability to re-populate areas destroyed following volcanic activity.
Evolutionary Relationships of Living Birds
The research team examined the evolutionary relationships of extant birds and their ecological habits to map how bird ecology has changed over time. The data revealed that the most common ancestor of all living birds, all the bird lineages that survived the K-Pg extinction event, most likely were ground-dwellers. In contrast, many Aves that lived at the end of the age of dinosaurs (and there were lots of them), exhibited tree-dwelling, arboreal habits. These species did not survive the mass extinction event and therefore they have no direct living descendants around today.
Daniel Field added:
“Today, birds are the most diverse and globally widespread group of terrestrial vertebrates, there are nearly 11,000 living species. Only a handful of ancestral bird lineages succeeded in surviving the K-PG mass extinction event 66 million years ago and all of today’s amazing living bird diversity can be traced to these ancient survivors.”
The researchers conclude that their findings shed light on the fundamental influence major events in the history of our planet have on the evolution of living things. The team hope to build on this initial research and to explore the timing of the recovery of the vegetation and to develop a better understanding of the early radiation of the birds. After all, those lucky survivors inherited a brave new world, devoid of non-avian dinosaurs and many other terrestrial and marine organisms too.
The scientific paper: “Early Evolution of Modern Birds Structured by Global Forest Collapse at the End-Cretaceous Mass Extinction” by Daniel J. Field, Antoine Bercovici, Jacob S. Berv, Regan Dunn, David E. Fastovsky, Tyler R. Lyson, Vivi Vajda and Jacques A. Gauthier published in the journal Current Biology.
Children in Year 2 at Great Wood Primary (Lancashire), sent in some super thank you letters to team members at Everything Dinosaur following a workshop at their school. The pupils have been learning all about dinosaurs for their summer term topic and last month, an Everything Dinosaur team member was invited into the school to deliver two dinosaur and fossil themed workshops, one for each Year 2 class.
A Set of Thank You Letters Sent to Everything Dinosaur by One Year 2 Class
Pupils at Great Wood Primary sent thank you letters to Everything Dinosaur. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Beautiful Letters from Year 2
During our workshop, lots of extension ideas surfaced and we always try to support the lesson plans and scheme of work of the teaching team. Challenging the class to write a letter to us gives an opportunity for the children to practice their handwriting and use of grammar. We received two sets of letters, one from each class and it was great to see such excellent examples of letter writing. Some of the children produced long letters, using two sheets of A4 paper, that is brilliant!
Lots and Lots of Letters for Us to Read – Here are the Letters from the Second Class
Children send in letters about dinosaurs. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Dinosaur Mike, who conducted the two workshops with the eager young palaeontologists from Great Wood Primary praised the children, saying:
“It was a great honour to receive the letters from Year 2. The correspondence was held up in the post and we had to go to the Royal Mail delivery centre to pick them up, but the trip was so worthwhile as we came back with two sets of super thank you letters. We really appreciate the letters and we have read them all.”
Everything Dinosaur Puts the Letters on Display
The team have read them all and they hope to post up responses to some of the questions the children asked. After laying the letters out onto the packing room floor in the company’s warehouse so they can be photographed, the letters will shortly be pinned up to the warehouse notice board. They will make a super display and they will help to remind Dinosaur Mike of his visit to the school. In the letters, the children inform us about their favourite part of the workshop. It seems that the children really enjoyed comparing their brain to the brain of a giant armoured dinosaur and handling fossils. The Tyrannosaurus rex tooth segment was also a favourite.
We wish the children and their hardworking Key Stage 1 teaching team every success with their dinosaur themed term topic and thank you once again for sending into Everything Dinosaur the wonderful correspondence.
An interesting headline featured on the front of a national newspaper here in the UK. It was spotted as an Everything Dinosaur team member went past a newspaper vendor this morning.
Intriguing Headline – Dinosaurs in Ermine
A headline from an English newspaper. Don’t worry it is not a report on a new dinosaur fossil discovery! Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
The headline certainly caught our attention. However, it was not a report on an amazing pseudo-mammal dinosaur fossil find, after all, palaeontologists have only now got some members of the public to accept the idea of dinosaurs with feathers.
Visit the award-winning and children-friendly website of Everything Dinosaur: Everything Dinosaur.
