All about dinosaurs, fossils and prehistoric animals by Everything Dinosaur team members.
//Key Stage 3/4

Articles that focus on teaching ideas and activities aimed at Key Stage 3 and Key Stage 4.

18 10, 2021

Scientists Find Remnants of Organic Molecules in the Cells of a Caudipteryx

By | October 18th, 2021|Adobe CS5, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Key Stage 3/4, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

An almost perfectly preserved specimen of the very bird-like theropod Caudipteryx has provided researchers with evidence of organic molecule preservation at a cellular and nuclear level. Writing in “Communications Biology”, scientists from the Institute of Vertebrate Palaeontology and Palaeoanthropology of the Chinese Academy of Sciences, in collaboration with colleagues from the Shandong Tianyu Museum of Nature (Shandong Province, eastern China), report on a study of fossilised cells from cartilage associated with a Caudipteryx thigh bone that reveal exquisite molecular preservation.

Photograph and line drawing of Caudipteryx specimen number STM4-3
Photograph of the Caudipteryx specimen (A) with (B) a close-up of the femur showing the extracted fragment outlined in yellow. Illustrative line drawing (C). Picture credit: Xiaoting Zheng et al.

Fragments from a Femur

The specimen (number STM4-3), is in the Shandong Tianyu Museum of Nature vertebrate fossil collection, one of the largest collections of dinosaur fossils in the world. It was collected from the Yixian Formation near Chaoyang City, Dapingfang Town (Liaoning Province) and is almost complete and partially articulated. Gastroliths are preserved in the stomach cavity and the outline of some feathers can also be seen. A right femur, measuring 15 cm in length was examined, a fragment removed representing cartilage and divided into three portions to permit detailed scanning electron microscopy (SEM), histochemical staining, energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM) along with chemical analysis.

The research team realised that some cells had been mineralised by silicification after the death of the animal. This silicification is most likely what permitted the excellent preservation of these cells.

Cauditperyx.
A model of the theropod dinosaur Caudipteryx.

Li Zhiheng, an Associate Professor at the Institute of Vertebrate Palaeontology and Palaeoanthropology and a co-author of the study commented that the discovery of cellular preservation in the cartilage was not unexpected stating:

“Geological data has accumulated over the years and shown that fossil preservation in the Jehol Biota was exceptional due to fine volcanic ashes that entombed the carcasses and preserved them down to the cellular level”.

Healthy Cells and Unhealthy, Dying Cells

The researchers discovered two main types of cells, cells that were healthy at the time of fossilisation, along with unhealthy cells that were porous and fossilised while in the process of dying.

Co-author Alida Bailleul (Institute of Vertebrate Palaeontology and Palaeoanthropology), explained:

“It is possible that these cells were already dying even before the animal died”.

Cell death is a process that occurs naturally throughout the lives of all organisms. But being able to identify a fossilised cell at a specific life stage within the cell cycle is quite new in palaeontology.

Staining the Nuclei of Dinosaur Cells

The team isolated some cells and stained them with a purple chemical used by biologists to identify nuclei material. This chemical, hematoxylin, is known to bind to the nuclei of cells. Cells from a chicken were also stained to provide an extant comparison. One dinosaur cell showed a purple nucleus with some darker purple threads. This provides strong evidence to support the idea that the 125-million-year-old dinosaur cell has a nucleus so well-preserved that it retains some original biomolecules and threads of chromatin.

Chromatin is found within the cells of all living organisms. It consists of tightly packed DNA molecules. The results of this study thus provide preliminary data suggesting that remnants of original dinosaur DNA may still be preserved.

Caudipteryx cells from the femur
Photographs of three cartilage cells from the femur of Caudipteryx. The purple chemical hematoxylin binds to the nuclei of cells. After the dinosaur cells were stained one cell showed a purple nucleus, this suggests that the 125-million-year-old fossil cell is so well preserved it has retained some original biomolecules and threads of chromatin. This cell replicated the reaction to hematoxylin expected from a cell of a living chicken. Picture credit: Alida Bailleul.

Much Further Work is Required

Whilst highlighting the significance of this study, after all discovering that 125-million-year-old dinosaur cells react to hematoxylin staining in the same way as living cells is remarkable, the researchers concede that a much more refined and precise approach will be required if dinosaur DNA is to be identified and recovered in any quantity.

The Jehol Biota.
The Jehol Biota approximately 125 million years ago. The corpse of the Caudipteryx lies on the lake shore whilst a pair of Psittacosaurus wander past and pterosaurs fly overhead. A Confuciusornis bird perches on a tree, undeterred by the erupting volcano nearby. Picture credit: Zheng Qiuyang.

In 2020, Everything Dinosaur reported upon the discovery of chromosome-like chromatin threads preserved in the fossilised cartilage of a 75-million-year-old hadrosaur (Hypacrosaurus stebingeri). This study identified nuclear and cellular preservation which was previously unknown in a Cretaceous fossil specimen. To read our article: Cartilage, Proteins and Potential Dinosaur DNA?

The scientific paper: “Nuclear preservation in the cartilage of the Jehol dinosaur Caudipteryx” by Xiaoting Zheng, Alida M. Bailleul, Zhiheng Li, Xiaoli Wang and Zhonghe Zhou published in Communications Biology.

14 09, 2021

Modern Snakes Evolved from a Handful of Species

By | September 14th, 2021|Animal News Stories, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Key Stage 3/4, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

New research published in the journal “Nature Communications” suggests that all extant snakes evolved from just a handful of species that survived the K-Pg extinction event 66 million years ago. The researchers conclude that this catastrophic extinction event, that wiped out the non-avian dinosaurs and something like 75% of all terrestrial life, was a form of “creative destruction” leading to a burst of evolutionary development within the Serpentes.

Snakes benefitted from the End-Cretaceous extinction event.
Snakes benefitted from the End-Cretaceous extinction event. It enabled them to evolve rapidly and to exploit new, ecological niches. Picture credit: Joschua Knüppe.

Snakes benefited from the extinction event, the loss of so many competitors allowed them to diversify rapidly and to occupy new niches in food chains.

The Snake Fossil Record

The fossil record of snakes is relatively poor because snake skeletons are typically small and fragile making the preservation of fossil material a rare event.

It is generally accepted that snakes (Suborder Serpentes), evolved from lizards. Snakes gradually losing their limbs, whether the first snakes were burrowers and evolved from burrowing lizards or whether the first snakes were adapted to a life in marine environments is an area of on-going debate between vertebrate palaeontologists. For example, in 2016 a team of scientists challenged the conclusions from the paper that described Tetrapodophis amplectus, a primitive snake-like animal from the Lower Cretaceous of Brazil. It had been suggested that T. amplectus, which had been described and named the year before, was adapted to a life underground, however, researchers from Canada and Australia challenged this view and proposed a marine habit for this 20 cm long animal that has been classified as being close to the base of the evolutionary lineage of true snakes.

Tetrapodophis Illustrated
The tiny limbs of Tetrapodophis may have been used to hold prey. Scientists are uncertain whether this animal was a burrower or adapted to a marine environment. Picture credit: Julius Csotonyi.

To read more about this research: Were the Very First Snakes Marine Reptiles?

Studying Fossils and the Genomes of Living Snakes

The research, led by scientists at the University of Bath in collaboration with researchers from Cambridge, Bristol and Germany, involved examining snake fossils and an analysis of the genomes of living snakes to pinpoint genetic differences permitting a picture of modern snake evolution to be built up.

The results indicate that despite the great variety of snakes alive today – cobras, vipers, pythons, boas, sea snakes and blind, burrowing snakes for example, all extant snakes can be traced back to a handful of species that survived the K-Pg extinction event that took place 66 million years ago.

A scientist examines a venomous Bushmaster snake (genus Lachesis), a type of pit viper known from Central and South America. Picture credit: Rodrigo Souza/Serra Grande Center.

Snake Survival Strategy

The authors postulate that the ability of snakes to shelter underground and go for long periods without food helped them survive the destructive effects of the bolide impact event. In the aftermath, the extinction of their competitors including Cretaceous snakes and small theropod dinosaurs, permitted snakes to move into new niches, new habitats and new parts of the world. Today, snakes are found in all but the highest latitudes and are present on every continent except Antarctica.

The researchers, which included lead author Dr Catherine Klein, a former graduate of Bath University but now based at the Alexander-Universität Erlangen-Nürnberg (FAU) in Germany, state that modern snake diversity – including tree snakes, sea snakes, venomous vipers and cobras, and huge constrictors like boas and pythons – emerged only after the non-avian dinosaur extinction.

Dr Klein commented:

“It’s remarkable, because not only are they surviving an extinction that wipes out so many other animals, but within a few million years they are innovating, using their habitats in new ways.”

A Change in Snake Vertebrae

Fossils also show a change in the shape of snake vertebrae in the aftermath, resulting from the extinction of Cretaceous lineages and the appearance of new groups, including giant sea snakes, such as Gigantophis garstini from the Eocene of northern Africa which may have reached a length of ten metres. Gigantophis was scientifically described in 1901, it was thought to have been the largest snake to have ever lived, until in 2009 when the giant, South American boa – Titanoboa cerrejonensis was described.

Rebor Titanoboa Museum Class Maquette Monty Resurgent.
The Rebor Titanoboa Museum Class Maquette Monty Resurgent. A model of the largest snake known to science.

Rapidly Spreading Around the Globe

The research team also suggest that snakes began to spread rapidly around the globe. The “Greenhouse Earth” conditions that occurred close to the boundary between the Palaeocene and Eocene Epochs that led to the establishment of extensive tropical forests in the Northern Hemisphere, would have facilitated the geographical spread of cold-blooded animals such as snakes.

Although the ancestor of living snakes probably lived somewhere in the Southern Hemisphere, snakes first appear to have spread to Asia after the extinction event.

Corresponding author, Dr Nick Longrich, from the Milner Centre for Evolution (University of Bath), explained:

“Our research suggests that extinction acted as a form of “creative destruction”- by wiping out old species, it allowed survivors to exploit the gaps in the ecosystem, experimenting with new lifestyles and habitats. This seems to be a general feature of evolution – it’s the periods immediately after major extinctions where we see evolution at its most wildly experimental and innovative. The destruction of biodiversity makes room for new things to emerge and colonise new landmasses. Ultimately life becomes even more diverse than before.”

Further Serpentes Evolution Driven by Climate Change

The researchers also found evidence for a second major diversification event around the time that the world shifted from a warm and moist climate to a colder, more seasonal climate (Oligocene Epoch).

It seems, that for the snakes at least, global catastrophes can have their upsides. The patterns seen in snake evolution hint at the key role played by mass extinction events – they are the catalysts for driving rapid evolutionary changes.

The scientific paper: “Evolution and dispersal of snakes across the Cretaceous-Paleogene mass extinction” by Catherine G. Klein, Davide Pisani, Daniel J. Field, Rebecca Lakin, Matthew A. Wills and Nicholas R. Longrich published in Nature Communications.

20 05, 2021

Horned Crocodile Gets a Home

By | May 20th, 2021|Animal News Stories, Key Stage 3/4, Main Page, Photos/Pictures of Fossils|0 Comments

Specimens of a strange, recently extinct crocodile housed at the American Museum of Natural History (New York), have helped unravel a mystery surrounding the evolutionary relationships of crocodilians. The skulls belong to the horned crocodile of Madagascar (Voay robustus) and a research team has demonstrated that it was closely related to “true crocodiles” – Crocodylus, making it the closest species to the common ancestor of the crocodile genus.

Voay robustus - horned crocodile skull
A skull of Voay robustus collected at Ampoza during the joint mission Franco-Anglo-American expedition from 1927–1930 (White, 1930). Picture credit: Hekkala et al.

Recently Extinct

When the first Europeans came to Madagascar the native Malagasy people told them about two distinct types of crocodiles that lived on their island. There was a gracile form that preferred rivers, this was identified as a population of Nile crocodiles (Crocodylus niloticus), but the swamps and lakes were home to a crocodile that the early explorers had never seen before. This second type was a much more heavy-set and powerful animal with two, bony bumps at the top of its skull.

When first named and described in 1872 (Grandidier and Vaillant), it was thought to be a species of true crocodile – a member of the Crocodylus genus. More recent studies have suggested affinities with the dwarf crocodiles (Osteolaeminae), however, with an estimated length of around 5 metres V. robustus was much larger than any other species assigned to this group.

New research published in the academic journal Communications Biology, which used DNA extracted from the American Museum of Natural History specimens, has resolved the phylogeny of this enigmatic reptile. Carbon dating of the material used in the study confirms that the horned crocodile probably survived until just a few hundred years ago.

Voay robustus phylogeny
The DNA study places the horned crocodile right next to the true crocodile branch of the evolutionary tree, making it the closest species to the common ancestor of the crocodiles alive today.

One of the authors of the scientific paper, Evon Hekkala, a research associate at the American Museum of Natural History stated:

“This crocodile was hiding out on the island of Madagascar during the time when people were building the pyramids and was probably still there when pirates were getting stranded on the island. They blinked out just before we had the modern genomic tools available to make sense of the relationships of living things. And yet, they were the key to understanding the story of all the crocodiles alive today.”

Mitochondrial DNA extracted from sub-fossil specimens found during a Franco-Anglo-American expedition to south-western Madagascar (1927 to 1930), demonstrates that V. robustus was not a true crocodile but very closely related to that lineage that led to them. Being placed next to the true crocodiles on an evolutionary tree suggests that it was the closest species to the common ancestor of extant members of the Crocodylus genus.

Voay robustus lower jaw.
The tip of the lower jaw (dentary) of the horned crocodile from Madagascar (Voay robustus). Carbon dating of the subfossils suggests that they are less than 1,400 years old. Picture credit: The American Museum of Natural History.

Co-author George Amato, (American Museum of Natural History), explained:

“This is a project we’ve tried to do on and off for many years, but the technology just hadn’t advanced enough, so it always failed. But in time, we had both the computational setup and the paleogenomic protocols that could actually fish out this DNA from the fossil and finally find a home for this species.”

“Teasing apart the relationships of modern crocodiles is really difficult because of the physical similarities,” Hekkala added. “Many people don’t even realise that there are multiple species of crocodiles, and they see them as this animal that’s unchanging through time. But we’ve been trying to get to the bottom of the great diversity that exists among them.”

Surprising Results

The close affinity of Voay to Crocodylus lends weight to the idea that Crocodylus originated in Africa and then dispersed into the Americas and Asia/Australia. Competing theories have proposed an Asian origin for Crocodylus but as Voay was restricted to Madagascar and has been cited as the closest species to the true crocodiles, this DNA analysis lends weight to the “African origins” idea.

The scientific paper: “Paleogenomics illuminates the evolutionary history of the extinct Holocene “horned” crocodile of Madagascar, Voay robustus” by E. Hekkala, J. Gatesy, A. Narechania, R. Meredith, M. Russello, M. L. Aardema, E. Jensen, S. Montanari, C. Brochu, M. Norell and G. Amato published in Communications Biology.

7 05, 2021

Nocturnal Dinosaurs Hunting in the Dark

By | May 7th, 2021|Adobe CS5, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Key Stage 3/4, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Scientists have proposed that the bizarre, chicken-sized alvarezsaurid Shuvuuia (S. deserti) had amazing eyesight and owl-like hearing, adaptations for a nocturnal hunter in its Late Cretaceous desert environment.

The Mongolian alvarezsaurid hunting at night
Shuvuuia deserti artist’s life reconstruction. Picture credit: Viktor Radermacher.

A Very Bizarre, Tiny Theropod

Named and described in 1998 from fossil material associated with the famous Djadochta Formation (Campanian faunal stage), Shuvuuia has been assigned to the Alvarezsauridae family of theropods. It may have been small (around 60 cm in length), but its skeleton shows a range of bizarre anatomical adaptations. It had long legs, a long tail, short but powerful forelimbs that ended in hands with greatly reduced, vestigial digits except for the thumb which was massive and had a large claw. The skull was very bird-like with disproportionately large orbits.

Photograph of fossilised Shuvuuia deserti skeleton.
Photograph of fossilised Shuvuuia deserti skeleton. Picture credit: Mick Ellison (American Museum of Natural History).

Writing in the academic journal “Science” a team of scientists led by Professor Jonah Choiniere (University of Witwatersrand, Johannesburg, South Africa), used sophisticated computerised tomography to examine the skull of Shuvuuia and to map this dinosaur’s sensory abilities, as part of a wider study into non-avian dinosaur sensory abilities.

Shuvuuia deserti fossil skull
Photograph of fossilised Shuvuuia deserti skull. Picture credit: Mick Ellison (American Museum of Natural History).

The international team of researchers used CT scanning and detailed measurements to collect data on the relative size of the eyes and inner ears of nearly 100 living bird and extinct dinosaur species. There are more than 10,000 species of bird (avian dinosaurs) alive today, but only a few have evolved sensory abilities that enable them to track and hunt prey at night. Owls are probably the best known, but not all owls are nocturnal. Kiwis hunt at night using their long, sensitive beaks to probe in the leaf litter for worms, whilst another bird endemic to New Zealand, the large, flightless Kakapo (a member of the parrots – Order Psittaciformes), is also nocturnal. Other birds active at night include the globally widespread black-capped night heron and the Stone-curlew (Burhinus oedicnemus) which is an occasional visitor to East Anglia in the UK.

To measure hearing ability, the team measured the length of the lagena, the organ that processes incoming sound information (known as the cochlea in mammals). The barn owl, which can hunt in complete darkness using hearing alone, has the proportionally longest lagena of any bird.

Barn owl skull CT scan showing lagena
Barn owl skull CT scan showing lagena. Picture credit: Jonah Choiniere/Wits University.

Assessing Vision

To examine vision, the team looked at the scleral ring, a series of bones surrounding the pupil, of each species. Like a camera lens, the larger the pupil can open, the more light can get in, enabling better vision at night. By measuring the diameter of the ring, the scientists could estimate how much light the eye can gather.

The researchers found that many carnivorous theropods such as large tyrannosaurs and the much smaller Dromaeosaurus had vision optimised for the daytime, and better-than-average hearing presumably to help them hunt. However, Shuvuuia, had both extraordinary hearing and night vision. The extremely large lagena of this species is almost identical in relative size to today’s barn owl, suggesting that Shuvuuia could have been a nocturnal hunter. With many predators sharing its Late Cretaceous desert environment, a night-time existence may have proved to be an effective strategy to avoid the attentions of much larger theropods.

Side by side comparison of the lagena of a Barn owl and Shuvuuia deserti
Side by side comparison of the lagena of a Barn owl (left) and Shuvuuia deserti (right). Picture credit: Jonah Choiniere/Wits University.

Commenting on the significance of this discovery, joint first author of the scientific paper, Dr James Neenan exclaimed:

“As I was digitally reconstructing the Shuvuuia skull, I couldn’t believe the lagena size. I called Professor Choiniere to have a look. We both thought it might be a mistake, so I processed the other ear – only then did we realise what a cool discovery we had on our hands!”

Extremely Large Eyes

The eyes of Shuvuuia were also remarkable. Skull measurements suggest that this little dinosaur had some of the proportionally largest pupils yet measured in birds or dinosaurs, suggesting that they could likely see very well at night.

Professor Jonah Choiniere holding a 3D Print of a Shuvuuia lagena
Professor Jonah Choiniere holding a 3D printed model of the lagena of Shuvuuia deserti. Picture credit: Jonah Choiniere/Wits University.

The Alvarezsauridae remain one of the most unusual of all the types of non-avian dinosaur known to science. Their place within the ecosystems of the Late Cretaceous remains controversial. Geographically widespread, a recently described alvarezsaurid from China Qiupanykus zhangi may have been a specialised ovivore (egg-eater), whilst other palaeontologists have postulated that these theropods used their strong forelimbs and large thumb claws to break into termite mounds. Perhaps, these small (most probably feathered), dinosaurs occupied a number of niches within Late Cretaceous ecosystems – including that of a nocturnal hunter of small vertebrates and insects.

Shuvuuia deserti artist's reconstruction.
Shuvuuia deserti artist’s reconstruction. Picture credit: Viktor Radermacher.

To read Everything Dinosaur’s blog article about Qiupanykus zhangi and the evidence behind the egg-eating theory: Did Alvarezsaurids Eat Eggs?

Everything Dinosaur acknowledges the assistance of a media release from the University of Witwatersrand in the compilation of this article.

The scientific paper: “Evolution of vision and hearing modalities in theropod dinosaurs” by Jonah N. Choiniere, James M. Neenan, Lars Schmitz, David P. Ford, Kimberley E. J. Chapelle, Amy M. Balanoff, Justin S. Sipla, Justin A. Georgi, Stig A. Walsh, Mark A. Norell, Xing Xu, James M. Clark and Roger B. J. Benson published in the journal Science.

3 04, 2021

Extra-terrestrial End-Cretaceous Impact Gave Rise to the Amazon Rainforest

By | April 3rd, 2021|Adobe CS5, Animal News Stories, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Key Stage 3/4, Main Page, Palaeontological articles|0 Comments

The Amazon rainforest is an extremely important low latitude habitat with a huge diversity of animals, fungi and plant species. Described as the “lungs of the planet”, this tropical rainforest is at the very centre of many global conservation efforts. New research suggests that it was the extra-terrestrial impact event some 66 million years ago that led to the rise of this angiosperm dominated ecosystem.

Earth impact event.
Cataclysmic impact event that led to the extinction of the dinosaurs and lots of other animal life. New research suggests that the dinosaur-killing bolide also gave rise to the Amazon rainforest ecosystem. Picture credit: Don Davis (commissioned by NASA).

K/Pg Extinction Event

Approximately 66 million years ago a rock from space smashed into our planet. This triggered a sudden mass extinction event devastating around 75% of all the animal and plant terrestrial species, many of which subsequently became extinct. At this time the dinosaurs, their cousins the pterosaurs and the majority of marine reptiles died out.

The end of the non-avian dinosaurs.
An artist’s impression of the bolide about to impact with the Gulf of Mexico 66 million years ago. This devastating event wiped out a large number of animals and plants, very probably contributing to the extinction of many different families including all the non-avian dinosaurs. Picture credit: Chase Stone.

Analysis of Fossil Pollen and Study of Fossil Leaves

Writing in the journal “Science”, researchers from the Southern Methodist University (Texas) and the University of Wyoming report on the study of tens of thousands of fossil pollen specimens along with thousands of leaf fossils from Cretaceous-aged strata and deposits laid down after the K/Pg extinction event. The scientists, which include co-author Dr Ellen Currano (Department of Botany, University of Wyoming), found that the types of plant creating tropical forests were very different pre and post the extra-terrestrial impact. In the Late Cretaceous tropical forests were dominated by conifers and they were much more open than the dense, angiosperm forests that came about during the Palaeocene.

Cretaceous maniraptora.
Study suggests the floral composition of tropical rainforests changed dramatically after the extra-terrestrial impact event. During the Late Cretaceous tropical forests were dominated by conifers and forest canopies were less dense. Picture Credit: Danielle Dufault.

A Thick Forest Canopy Denying Access to Light

The scientists discovered that the fossil pollen and leaves show a marked transition in tropical forest flora. After the extra-terrestrial impact forests developed a thick canopy blocking much of the light from reaching the ground and angiosperms became more dominant.

A view of a modern tropical rainforest canopy.
An aerial view of the dense angiosperm dominated canopy of a modern rainforest. Picture credit: BBC.

How Did These Changes Come About?

As well as the documenting the turnover in flora and the transition from one tropical forest environment to a different type of rainforest in the Palaeocene, the researchers propose three possible explanations for this change:

  1. The absence of large megaherbivores, specifically dinosaurs allowed plant densities in forests to increase. The extinction of giant plant-eating dinosaurs such as the Ceratopsia, hadrosaurs, armoured dinosaurs and the titanosaurs allowed plants to grow at lower levels as they were not being trampled or consumed by herbivorous dinosaurs.
  2. Several types of fern and conifer became extinct during the K/Pg transition permitting new types of angiosperm (flowering plants) to evolve and exploit the vacated niches.
  3. Falling ash from the impact enriched soils throughout the tropics, provided an advantage to faster-growing angiosperms.
The floral composition of rainforests radically altered after the K/Pg extinction event.
The floral composition of rainforests radically altered after the K/Pg extinction event. Picture Credit: BBC.

The scientists conclude that the three hypotheses are not mutually exclusive and that a combination of factors could have led to the change in the flora as recorded in the fossil record.

A Significant Lesson for Today

Today, a rapidly changing climate, largely caused by the actions of our own species is having a dramatic effect on the world’s forests. The researchers note that the fossil record demonstrates that rainforests do not simply “bounce back”, after a catastrophe. They can take millions of years to recover and a very different type of ecosystem is likely to emerge.

The scientific paper: “The impactful origin of neotropical rainforests” by Bonnie F. Jacobs and Ellen D. Currano published in the journal Science.

30 04, 2020

“Crazy Beast” Lived Amongst the Last of the Dinosaurs

By | April 30th, 2020|General Teaching, Key Stage 1/2, Key Stage 3/4|Comments Off on “Crazy Beast” Lived Amongst the Last of the Dinosaurs

Adalatherium hui – “Crazy Beast” from Madagascar

Scientists have published a scientific paper in the academic journal “Nature” that describes a cat-sized mammal that lived alongside the dinosaurs at the very end of the Cretaceous.  The furry little creature has been named Adalatherium hui and its fossils have been found on the island of Madagascar.  Madagascar started to  break away from the super-continent of Gondwana around 88 million years ago and so animals such as Adalatherium evolved in relative isolation, separated from other populations of mammals on larger landmasses.  At around three kilograms in weight and not being fully grown when it died, it challenges the perception that all mammals were very small during the time of the dinosaurs.

A Life Reconstruction of the Late Cretaceous Mammaliaform Adalatherium hui

Late Cretaceous mammaliaform Adalatherium.

Adalatherium life reconstruction.  Although it is thought this animal lived in burrows like a modern badger, the colouration of this life reconstruction is speculative.

Picture Credit: Reuters

“Crazy Beast”

Adalatherium lived around 72 million to 66 million years ago (Late Cretaceous).  The genus name translated from the Greek and native Malagasy means “crazy beast”, as the discovery of skull and postcranial fossil material of this badger-like creature challenges a lot of scientific assumptions about the evolution of mammals during the latter stages of the Mesozoic.  The snout had a large congregation of nerves within it, making the nose of this animal extremely sensitive.  This suggests that sense of smell was very important and therefore, it has been proposed that Adalatherium lived underground, that it was a burrowing animal (fossorial – an animal adapted to digging and living in burrows).

Adalatherium shared its island home with a number of predatory dinosaurs, including abelisaurids, dromaeosaurs and noasaurids as well as at least three species of crocodilians, both ancient forms and distant relatives of today’s living crocodiles (Neosuchian crocodilians).

Perhaps living underground was a very sensible strategy when surrounded by large predators.

Extensions

  • Make a list of animals alive today that live in burrows
  • What similarities do they have?  What differences can you spot?
  • Can you design a dinosaur that could live underground?  What sort of adaptations would this animal have?
6 04, 2020

Not All Dinosaurs were Feathered

By | April 6th, 2020|General Teaching, Key Stage 3/4|Comments Off on Not All Dinosaurs were Feathered

There were Feathered Dinosaurs but not all Dinosaurs were Feathered

Research conducted by palaeontologists at the London Natural History Museum suggests that whilst dinosaurs that were closely related to modern birds (Aves), were probably feathered, other types of dinosaurs such as the Late Cretaceous horned dinosaurs and the duck-billed dinosaurs probably were not covered in feathers.  A book tracing the evolution of feathers is being written and as part of the background to this forthcoming publication, Professor Paul Barrett of the Museum conducted an evolutionary analysis looking at the preserved skin fossils of the 77 dinosaur species where evidence of skin has been preserved.

A Preserved Skin Impression from a Tyrannosaurus rex

T. rex skin impression fossil.

A skin impression associated with Tyrannosaurus rex.  Dinosaurs such as tyrannosaurs may have been feathered, at least whilst they were young animals but there are no signs of feathers or an integumentary covering associated with T. rex skin impressions.

Picture Credit: Biology Letters

Evidence of Reptilian Scaly Skins

The study suggests that the first types of dinosaurs were probably covered in scaly skin and not feathered.  Professor Barrett and his colleagues found no evidence of the earliest members of the Dinosauria being feathered.  Most of the fossil evidence supports the view that a specific proportion of the Theropoda (mostly meat-eating dinosaurs), the Coelurosauria – were feathered.  No evidence for a feathery covering in long-necked, plant-eaters (Sauropodomorpha) has been identified to date.

Sinosauropteryx – The First Dinosaur with Feathers to be Described

Sinosauropteryx fossil.

Sinosauropteryx fossil – the first feathered dinosaur to be described.  This small Chinese dinosaur is a member of the Coelurosauria clade of theropods, the group of theropods most closely associated with feathers.

Picture Credit: Everything Dinosaur

The First Feathered Dinosaur Fossils were Found in China

Sinosauropteryx a feathered dinosaur.

Analysis of Sinosauropteryx fossil material suggests that this little dinosaur had ginger feathers.

Picture Credit: J. Robbins

The book is due to be published later on this year, a spokesperson from Everything Dinosaur commented that it would add to the growing list of books aimed at the general reader that helped to explain some of the areas of research currently being conducted on the Dinosauria.

For further articles about feathered dinosaurs and research:

Tyrannosaurus rex loses its feathers: T. rex Sheds its Feathers.

The origins of feathers: Feathers came first, then Birds Evolved.

Did all Dinosaurs have feathers? Did all Dinosaurs have Feathers?

Extension Ideas

  • What evidence can you find for dinosaurs having feathers?  Can you draw up a simplified family tree of the Dinosauria identifying which types of dinosaurs were feathered?
  • What are the reasons for large animals such as the sauropods probably not having a feathery covering?  A hint, think surface to volume ratios and how large animals need to prevent overheating.
  • Create a poster/chart comparing a bird to a meat-eating dinosaur.  What are the similarities, what are the differences?
  • Why do you think some dinosaurs were feathered?  Can you come up with a theory?
28 03, 2020

Fossil Skull Reveals Origin of Modern Birds

By | March 28th, 2020|General Teaching, Key Stage 3/4|Comments Off on Fossil Skull Reveals Origin of Modern Birds

“Wonderchicken” Fossil Reveals Origin of Modern Birds

The oldest fossil of a modern bird yet found, dating from the very end of the Cretaceous, has been identified by an international team of palaeontologists led by researchers from the University of Cambridge.  Sophisticated CT scans (computerised tomography), of a limestone rock, not much bigger than a pack of cards, revealed the exquisitely preserved fossil skull.  Fragments of bone exposed on the rock’s surface suggested that there were more bones buried deep in the rock, but the scientists were not expecting to find the near perfect fossilised skull of a modern bird (neornithine), once the CT scans had been completed.

The bird has been nicknamed “wonderchicken” as its skull shows characteristics found in modern ducks and chickens.  This suggests it is close to the last common ancestor of these types of birds.

A Life Reconstruction of “Wonderchicken” – Asteriornis maastrichtensis

Life reconstruction - Asteriornis maastrichtensis .

Asteriornis maastrichtensis life reconstruction.

Picture Credit: Philip Krzeminski

The fossil comes from a limestone quarry on the Netherlands-Belgium border, making it the first modern bird from the age of dinosaurs to have been found in the northern hemisphere.

Named Asteriornis maastrichtensis, this quail-sized bird (to which it is distantly related), exhibits a previously undocumented combination of galliform-like (landfowl) and anseriform-like (waterfowl) anatomical traits.  Its presence alongside a previously reported Ichthyornis-like bird from the same quarry provides direct evidence of the co-occurrence of crown birds and avialan stem birds.

The Limestone Rock which Contains the Fossil Skull

The lump of limestone ontaining the skull of Asteriornis maastrichtensis.

The limestone containing the skull of Asteriornis maastrichtensis.

Picture Credit: Dr Daniel Field (Cambridge University)

Small Size Could Have Saved Modern Birds from Extinction

Asteriornis was quite small, certainly much smaller than the pterosaurs that it shared the skies with.  The fossil has been dated to 66.8-66.7 million years ago, a few hundred thousand years before the dinosaurs and lots of other animals including many types of bird, died out.

The authors of the scientific paper (published in the journal Nature), speculate that as it was small and it lived by the sea, this way of life, fitting a particular niche in the Late Cretaceous ecosystem, may have helped the ancestors of today’s birds to survive the end-Cretaceous mass extinction event that wiped out the dinosaurs.

12 03, 2020

Remarkable Tiny Dinosaur Discovery Coincides with British Science Week

By | March 12th, 2020|General Teaching, Key Stage 3/4|Comments Off on Remarkable Tiny Dinosaur Discovery Coincides with British Science Week

Remarkable Tiny Dinosaur Discovery Coincides with British Science Week

Everything Dinosaur marks British Science Week 2020 by reporting on the remarkable discovery of a tiny fossilised skull preserved in amber from northern Myanmar (Burma).  The fossil skull, which measures just 14 millimetres long represents a new species within the clade Dinosauria.  It has been named Oculudentavis khaungraae it probably weighed about as much as the smallest living bird, the Bee Hummingbird.  Scientists have estimated that it was around 8-10 centimetres long.  This makes Oculudentavis the smallest dinosaur known to science.

The Tiny Skull of the Newly Described Oculudentavis khaungraae Preserved in Amber from Myanmar

Tiny skull peserved in amber from northern Myanmar.

Oculudentavis skull preserved in amber.  The tiny fossil skull is on the right amongst a lot of other debris and organic material trapped in the fossilised tree resin.  The narrow jaws and the large eye can be clearly made out.

Picture Credit: Lida Xing et al

Team members at Everything Dinosaur have compared Oculudentavis to Tyrannosaurus rex (a distant relative of this tiny creature).  They estimate that an adult Tyrannosaurus rex weighed around 3.5 million times heavier.  Ironically, the tiny teeth in the jaw of Oculudentavis suggest that just like T. rex it was a predator.  It probably hunted insects.  The fossil is estimated to be around 99 million years old.

The fossil discovery represents the smallest member of the Mesozoic Dinosauria clade known to science and it demonstrates the importance of amber as a means of permitting scientists to gain an insight into the ecology of an ancient habitat thanks to the preservation of small animals and other material in fossilised tree resin.

Specimens preserved in amber are emerging as an exceptional way to study very small animals that once lived alongside the generally much larger pterosaurs and dinosaurs.

What an amazing fossil discovery, the publication of the scientific paper having coincided with British Science Week.

Note

The conclusions of the scientific paper have been challenged, this fossil might represent the preserved remains of a lizard.

 

2 09, 2019

Making Preparations for KS3

By | September 2nd, 2019|Key Stage 3/4|Comments Off on Making Preparations for KS3

Making Preparations for Key Stage 3

It has been a busy end to August for our teaching team as they finalise plans for school and college visits over the autumn term (2019).  All has been put in place and prepared as the schools start back.  We have dealt with the last minute enquiries and provided what support and assistance that we can.  Everything Dinosaur team members are involved in a variety of teaching projects including some work with Key Stage 3 and Key Stage 4 students.  Our aim is to support the science element of the curriculum, especially those areas related to biology, chemistry and genetics.

In addition, we have been contacted with requests for careers advice.

The Practical Implications of Scientific Working

Advice on fieldwork has been provided by Everything Dinosaur.

Learning about evolution, Darwin and genetics by studying the fossil record.

The Purpose of Key Stage 3 Science

When preparing lesson plans for older students (KS3 and KS4), we keep a list on the desk which reminds of the purpose of science for these age groups.  This helps us to focus on meeting the learning needs of the class.

For example, here is the list we use when considering a KS3 class (Year 7 to Year 9).

  • Use scientific ideas, theories and models to help explain current/past events (link to evolution and to climate change).
  • Build on existing scientific knowledge from Key Stage 2 and to make connections between the different scientific disciplines.
  • Understand a range of familiar, everyday applications of science.
  • Consider the advantages and disadvantages of scientific developments in the context of their impact on the environment, humanity and the planet
  • Explore different views on topic areas and consider the reasons for these differences.
  • Emphasis the role of building empirical and experimental evidence to support findings and scientific ideas.
  • Design and conduct investigations of different types, making use of available resources and reference sources.
  • To critique and evaluate the experiments undertaken and to consider how the research could be improved/developed.
  • To consider the role of scientific communication in disseminating research findings – how does science reach a wider audience?

These lists that we have developed act as an “aide mémoire” to ensure that we remain focused on the learning needs of each class.

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