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/Geology

Articles, features and stories with an emphasis on geology.

16 11, 2017

Cataloguing the Ancient Forests of Antarctica

By | November 16th, 2017|Dinosaur and Prehistoric Animal News Stories, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Permian, Triassic and Jurassic-aged Forests Explored on the Coldest Continent

Over the next few months, a team of intrepid scientists will be hoping to continue their exploration of some of the most remote fossil locations in the world.  Researchers from the University of Wisconsin-Milwaukee have been mapping the sedimentary deposits at McIntyre Promontory, at the head of the Ramsey Glacier in Antarctica.  To date, the team have recorded an extensive series of strata ranging in ages from the Late Permian to the Jurassic, the numerous plant fossils found are helping the scientists to better understand the evolution of forests and their flora over the southernmost portions of Gondwana.

Remains of Prehistoric Forests Uncovered in Antarctica

Prehistoric tree trunk (geology hammer provides scale).

An ancient tree trunk discovered in Antarctica.

Picture Credit: University of Wisconsin-Milwaukee

Antarctica in the Late Permian Period

A total of thirteen trees have been found with numerous fragmentary fossils of other plants, including Ginkgos and Glossopteris.  The oldest plants described by this research team, date from the Late Permian of around 260 million years ago.  Some of the fossils have stems and roots attached and have been preserved “in situ”.  No transport of fossil material is involved, the fossils are preserved where the plants grew.  The flora of this southerly habitat has been preserved thanks to occasional volcanic events that buried the primitive forests in ash.

Commenting on the significance of the Antarctic ancient flora, palaeoecologist and visiting assistant professor at the University of Wisconsin-Milwaukee Department of Geosciences, Erik Gulbranson stated:

“People have known about the fossils in Antarctica since the 1910-12 Robert Falcon Scott expedition.  However, most of Antarctica is still unexplored.  Sometimes, you might be the first person to ever climb a particular mountain.”

Beautifully Preserved Plant Fossils

Ancient plant fossils from Antarctica.

Ancient plant fossil remains.

Picture Credit: University of Wisconsin-Milwaukee

The Late Permian forests preceded the most extensive mass extinction event in the Phanerozoic (end Permian mass extinction event),  the scientists are hoping to use their growing knowledge of the ancient Antarctic forests to look at the possible impact on global warming on extant plant communities.  In addition, as the Antarctic forests grew at polar latitudes where plants can’t grow today, Gulbranson believes that the trees were an extremely hardy species and he and his colleagues are trying to determine why they died out.

Just like their modern counterparts, prehistoric tree fossils can reveal seasonal growth rings.  These rings when examined in microscopic detail can reveal patterns of seasonal growth.  Antarctica during the Late Permian was further north than it is today, even so, despite the milder climate, the forests would have had to endure prolonged periods of darkness, when the sun never emerged above the horizon.  The research team hopes to use the ancient growth rings to learn more about how these forests coped with such extremes.

Ancient Tree Trunks Can Help Decipher Seasonal Growth Patterns

Antarctic prehistoric plant life.

Ancient trees can reveal evidence of seasonal growth.

Picture Credit: University of Wisconsin-Milwaukee

Climate Change and the End Permian Mass Extinction Event

The cause or causes of the end Permian extinction event remain an area of controversy within palaeontology, although many scientists now believe that a huge increase in atmospheric greenhouse gases such as methane and CO2 which resulted from extensive global volcanic activity led to world-wide climate change.  John Isbell (University of Wisconsin-Milwaukee), has visited Antarctica before, on this expedition he examined the matrix and other sediments surrounding the in situ fossils to determine how these plant remains fitted into the geology of Antarctica.

To read an article written by Everything Dinosaur in 2015, that explains how rocks from South Africa are helping scientists to unravel global extinction events: Karoo Rocks Provide a Fresh Insight into Extinction Events

The Plant Fossils Might Represent New Species

The prehistoric forests of Antarctica.

Delicate plant fronds have been preserved.

Picture Credit: University of Wisconsin-Milwaukee

The extensive forests may have stretched across the whole of the super-continent Gondwana.  Evidence of Glossopteris fossils and other plant remains have been used to help substantiate the theory of continental drift.  These Permian forests would have looked very different from today’s temperate woodlands, the flora would have been dominated by mosses, ferns, Pteridosperms (seed ferns) and conifers.

Erik Gulbranson explained that the Antarctic fossils have provided important information about plant diversity at higher latitudes. During the Permian, forests were a potentially low diversity assemblage of different plant types with specific functions that affected how the entire forest responded to environmental change.  This is in direct contrast to today’s high-latitude forests that display greater plant diversity.

Gulbranson added:

“This plant group must have been capable of surviving and thriving in a variety of environments.  It’s extremely rare, even today, for a group to appear across nearly an entire hemisphere of the globe.”

Tough Forests Failed to Survive Climate Change

The researchers conclude that these tough trees and plants did not survive the climate change that marked the end of the Permian.  Younger plant fossils from Triassic and Jurassic sediments provide evidence of the changing Antarctic flora over time, but many of the types of plants found in the Permian forests, despite their resilience, died out.

Erik Gulbranson Can Study the Permian Plant Fossils in the University Laboratory

Plant fossils being examined.

Examining the Permian plant fossils (Erik Gulbranson – University of Wisconsin-Milwaukee).

Picture Credit: University of Wisconsin-Milwaukee/Troye Fox

By analysing the preserved tree growth rings, the scientists have found that these trees transitioned from summer activity to winter dormancy very rapidly, perhaps within a few weeks.  Extant plants make the same transition over the course of several months and also conserve water by making food during the day and resting at night.  Scientists don’t yet know how months of perpetual light would have affected the plants’ day-and-night cycles.

The team hope to return to the various Antarctic dig sites in the early part of 2018.  They hope to learn more about the annual growth cycles of the trees and to determine how the forests coped with rising levels of greenhouse gases and a warming climate.  It is hoped that by studying the Permian flora of Antarctica, models looking at how living plants will cope with climate change can be developed.

5 11, 2017

Chicxulub Impact – A Really Bad Place to Hit

By | November 5th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page|0 Comments

Chicxulub Impact – The Big Freeze

For life on Earth, the impact event that marked the end of the Mesozoic Era was made many times worse as the extra-terrestrial object caused the release of climate-active gases.  As if the devastation was not bad enough, the high-velocity impact caused the release of huge quantities of sulphur and carbon dioxide into the atmosphere triggering a dramatic world-wide cooling and exacerbating the effect of this event.  No wonder then, that around 70% of all terrestrial life died out.  Two scientific papers report on the consequences of this catastrophe.  In the first, the effect of gases released into the atmosphere from the sedimentary rocks that were hit are modelled and in the second paper, scientists look at just how unfortunate the dinosaurs were.  If the extra-terrestrial object had hit virtually anywhere else on Earth, the consequences for Cretaceous life would not have been so severe.

In simple terms, the dinosaurs were very unlucky, there was only a 13% chance of a mass extinction event occurring 66 million years ago when the object from space hit.

An Extra-terrestrial Object Hurtles Towards Earth 66 Million Years Ago

Asteroid strikes the Earth.

An extra-terrestrial impact event.   The dinosaurs were very unlucky.

Picture Credit: Deposit photos/Paul Paladin

A Global Effect

Writing in the journal “Geophysical Research Letters”, the authors of the first scientific paper report that the impact in the shallow sea of the Gulf of Mexico may have resulted in the expulsion of more than 300 billion tonnes of sulphur into the atmosphere.  In addition, the rocks that the object hit also released vast quantities of carbon dioxide, somewhere around 400 billion tonnes of CO2.   Some of the sulphur may have combined with water vapour to form sulphuric acid, this would have fallen back to Earth in the form of acid rain, further damaging plant life and upsetting food chains.  However, much of the gas would have remained high up in the atmosphere and behaved like aerosols, changing the amount of solar irradiation reaching the ground which led to surface temperatures plummeting.

The global effect was freezing temperatures for several years, a nuclear winter.  The research team which includes scientists from the Imperial College London and Potsdam University, conclude that ocean temperatures could have been affected for hundreds of years.  The abrupt climate change may explain why so many species become extinct.  The end-Cretaceous mass extinction event saw entire groups of animals and plants die out including the non-avian dinosaurs, the Pterosauria, several types of marine reptiles, as well as cephalopods such as the ammonites.  In addition, there were major losses amongst brachiopods, bivalves, sea urchins and many different types of marine plankton also perished.  Although, in comparison, groups such as the flowering plants (Angiosperms), amphibians, mammals and fishes were less affected, there were still extinctions.

Hitting the Earth in a Very Bad Place

Plummeting temperatures and a sustained period of intense cold would have made survival for the likes of the Dinosauria, extremely difficult.  Such a dramatic climate downturn would have devastated ecosystems, leaving animals like the non-avian dinosaurs and flying reptiles doomed.  However, in a second paper published in the journal “Scientific Reports”, scientists from Tohoku University and the Meteorological Research Institute, Tsukuba (both in Japan), state that life on Earth 66 million years ago, was just unlucky.  According to the calculations of these scientists, there was only a thirteen percent chance of the mass extinction event that wiped out the dinosaurs.  If the extra-terrestrial object had hit almost anywhere else, the consequences would not have been so severe and the Dinosauria et al might just have survived to the present day.

Examining the Consequences of the Yucatan Peninsula Impact

Unlucky dinosaurs - asteroid impact in the wrong place.

A devastating mass extinction could only occur if an asteroid struck a hydrocarbon-rich area (those marked in orange).

Picture Credit: Kunio Kaiho (Tohoku University)

The Japan-based researchers postulated that the severity of the climate change would vary depending on where the extra-terrestrial body hit.  Areas with higher levels of sedimentary organic material would throw more soot into the upper parts of the atmosphere.  More hydrocarbons present would result in greater releases of CO2.  Those areas with sulphur-rich rocks would have released more sulphur.  The team conclude that the effects of the impact were much more dramatic because the impact was in the Gulf of Mexico.  To test their hypothesis, a series of impact scenarios were run using global climate models to assess changes in temperature.

When the Yucatan Peninsula Cretaceous geology was examined, the team concluded that the hydro-carbon rich strata would have thrown debris into the upper atmosphere that resulted in a drop of global temperature by an average of 8 to 11 degrees Celsius.  On land, the temperature drop could have been as excessive as a fall of 17 degrees Celsius.  The oceans did not fare much better, with average temperature drops of between 5 and 7 degrees Celsius at depths of up to fifty metres.  Putting this into context, our world is faced with global climate warming.  The Paris Agreement, now ratified by 169 countries, has a central aim to keep the global temperature rise this century to below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius.

Very Unlucky Dinosaurs

The extinction of the dinosaurs.

Had the impact event taken place anywhere else on the planet, its consequences for life on Earth might not have been so severe.

Picture Credit:

The researchers looked at how widespread the sort of rocks found in the Yucatan Peninsula in the Cretaceous, were.  They found that these types of rocks were mostly associated with marine coastal margins.  The shallow seas permitted the concentration of algae which could deposit more organic matter into the sediments.  These areas covered just thirteen percent of the Earth’s surface.

Had the asteroid struck somewhere in the other eighty-seven percent of the planet, then, although the impact event would have been catastrophic, it might not have been as bad as it was.  The researchers even go as far as to state that some species of dinosaurs may have persisted beyond the Cretaceous.  The Mammalia would not have had the chance to radiate and therefore the primates, including humans, might not have evolved at all.

Changes in Fauna over the Phanerozoic Based on Extinction Events

The probability of dinosaur extinction.

Looking at the probability of a mass extinction event (Chicxulub impact).

The graph above shows Phanerozoic faunal changes with approximately 13% probability following the Chicxulub asteroid impact.  Changes in fauna are based on extinction rates.   A consequence of the end Cretaceous extinction event was the demise of the Dinosauria and the rise of mammals.

Sometimes it can come down to serendipity.

17 10, 2017

Iron Oxide and Iron Deposits

By | October 17th, 2017|Geology, Main Page|0 Comments

Banded Iron Formation

Whilst in Frankfurt a few days ago, a team member from Everything Dinosaur took the opportunity to photograph some of the amazing outdoor exhibits on display opposite the Senckenberg Naturmuseum (Frankfurt Natural History Museum).  Amongst the stunning replicas of prehistoric plants and of course, the iconic, life-size model of Tyrannosaurus rex, our staff member spotted a beautiful example of a banded iron formation.

Not Too Difficult to Spot – A Huge Monolith (Banded Iron Formation)

Banded Iron Formation

An example of a banded iron formation.

Picture Credit: Everything Dinosaur

A Record of a Changing Atmosphere on Planet Earth

Formed in marine environments at least 2.5 billion years ago, these deposits provide information about when the atmosphere of our planet and its oceans became oxygenated.  Iron oxide is not soluble, therefore the iron must have been transported in a non-oxidised form.  This could only have happened if there was almost no oxygen in the atmosphere or the oceans.

A Closer View of the Iron Banded Formation Showing the Deposition

A banded iron deposit close-up.

The individual layers can be clearly seen in this banded iron deposit.

Picture Credit: Everything Dinosaur

The picture above shows a close-up view of the banded layers.  Each layer is quite thin and these patterns are usually formed by alternating bands of iron-rich material (usually magnetite) and silica (chert).  During the Archean Eon, the primitive Earth had little free oxygen.  Rocks rich in iron were weathered at the surface and this iron remained largely unchanged as there was no free oxygen to combine with it and create iron oxide (rust).  The iron ions entered the sea in an unaltered chemical state.  They formed the band of iron-rich material seen in some of the layers. However, primitive cyanobacteria (blue/green algae), were beginning to become more abundant in surface waters.  As algae populations grew, there was a subsequent increase in photosynthesis.  Oxygen is a bi-product of photosynthesis and this free oxygen began to combine with the iron ions in the water to form magnetite (Fe3O4), iron oxide.  As more and more algae photosynthesised so the amount of oxygen available to combine with the iron increased, until a point was reached whereby the O2 production of the biomass in the marine ecosystem exceeded the amount of iron that was available to combine with.  The oxygen was left in the ocean and this gas rose to toxic levels decimating the cyanobacteria.  The algae population collapsed and led to the accumulation of a sedimentary layer on the seabed low in iron (the chert).  Over time, something like 800,000 years, algal blooms and peaks and troughs of oxygen production via photosynthesis led to the banded formations seen today in rocks dating from the Archean.

10 07, 2017

Swiss Fossil Discovery Solves Triassic Reptile Mystery

By | July 10th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page|0 Comments

The Marine Reptile That Wasn’t –  Eusaurosphargis dalsassoi

A team of scientists from Zurich University and the University of Oxford have resolved a scaly, fourteen-year mystery concerning a small reptile that lived some 241 million years ago in the Middle Triassic.  The little diapsid named Eusaurosphargis dalsassoi has had quite a chequered history, but thanks to a remarkable fossil find, palaeontologists have a much better idea of what this reptile looked and equally importantly where it lived.  This animal was very much at home on land and not a marine reptile as previously thought.

An Illustration of Eusaurosphargis dalsassoi

Eusaurosphargis dalsassoi.

Eusaurosphargis dalsassoi illustrated.

Picture Credit: Beat Scheffold, Palaeontological Institute and Museum, University of Zurich

Fossil Discovery in 2003

Named from a single, disarticulated specimen found in marine strata on the Swiss-Italian border some fourteen years ago Eusaurosphargis was thought at first to be some form of fish, after all, the fossil was found in rocks formed from sediment laid down in a shallow lagoon.  Once the skeleton had been prepared, the fossil material was identified as a diapsid reptile and the taphonomy suggested that this was a reptile that lived in the sea.  Taphonomy is the study of the fossilisation process.  It concerns everything that happens to an organism from death until the time when, if serendipity permits, its fossil is discovered.  A new fossil find, this time from the Grisons Mountains (Graubünden canton of Switzerland), a much more complete and articulated specimen, has revealed the true nature of Eusaurosphargis, it was definitely a land-lubber and as such has a superficial similarity to the extant girdled lizards (Cordylidae) of southern Africa.

A Beautifully Well-Preserved Fossil Proves Eusaurosphargis was Terrestrial

Eusaurosphargis fossil.

The articulated fossil skeleton of Eusaurophargis.

Picture Credit: Torsten Scheyer, Palaeontological Institute and Museum, University of Zurich

No Sign of Marine Adaptations

The Swiss specimen measures around twenty centimetres in length and as such, it represents a juvenile.  However, the skeleton shows a flange of osteoderms on the side of the body along with a number of bony scales on its back.  The sprawling limbs show no signs of adaptation for a swimming lifestyle and the tail is very short, so short, that in water it would not have provided much propulsion.  This fossil, excavated from the Prosanto Formation near Ducanfurgga at an altitude of 2,740 metres, strongly supports the idea that this was a terrestrial animal.

Writing in the academic journal “Scientific Reports”, the Anglo-Swiss team of researchers led by Torsten Scheyer, a palaeontologist at the University of Zurich, and James Neenan from the Oxford University Museum of Natural History have concluded that the carcass was washed off a nearby island into the sea basin and became embedded in the finely layered marine sediments after death.

Convergent Evolution

Commenting on the superficial resemblance between the Triassic Eusaurosphargis and modern-day members of the Cordylidae family, Dr Scheyer explained:

“This is a case of convergent development as the extinct species is not closely related to today’s African lizards.”

The Site of the Fossil Discovery – in the Middle of a Mountain Range

Triassic reptile fossil site.

The location of the Eusaurosphargis fossil discovery.

Picture Credit:  Christian Obrist

The Irony of the Phylogeny of Eusaurosphargis dalsassoi

Based on this new, and much better-preserved fossil material, the research team were able to conduct a more detailed phylogenetic study of E. dalsassoi to establish where, in the extremely diverse Diapsida this little reptile should be nested.  The phylogenetic analysis indicates that its closest relatives were marine reptiles, animals such as Ichthyosaurs.  Eusaurosphargis may even be the sister taxon to Helveticosaurus, a Mid Triassic marine reptile, fossils of which, also come from Switzerland.

8 07, 2017

A Time for Digging Up Dinosaurs

By | July 8th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page, Palaeontological articles|0 Comments

Field Teams Prepare to Explore Northern Latitudes

High summer in the northern hemisphere, most teaching programmes may have come to an end but for many palaeontologists, this is their busiest time of year.  The months of July and August represent the best times to explore some of the more remote and difficult to access vertebrate fossil sites.  Take for example, Dr Anthony Fiorillo from the Perot Museum of Nature and Science (Dallas, Texas).  He and his colleagues are busy organising field work in the Aniakchak National Monument (Alaska), area in a bid to learn more about polar dinosaurs.  The summer months represent the only time that scientists have to work at such remote and inaccessible sites, as the weather for once, is on their side.  Palaeontologists will be taking advantage of the near 24-hours of daylight in northern latitudes to further explore the unique prehistoric environments that for most of the year are simply inaccessible.

Dr Tony Fiorillo at Work in the Field

Dr Fiorillo (Perot Museum of Nature and Science)

Dr Anthony Fiorillo in the field ready to dig up dinosaurs.

Picture Credit: Perot Museum of Nature and Science

Dinosaurs of Northern Latitudes

The Late Cretaceous exposures in Alaska provide a record of life at very high latitudes as the age of dinosaurs was drawing to a close.  Just like the herds of migratory herbivorous dinosaurs, which would have fed around the clock, the scientists will be taking advantage of the very long days to get as much work done as possible.  The field team hope to revisit a number of locations in the Aniakchak National Monument in a bid to collect more data on the hundreds of dinosaur tracksites that have been discovered.  These tracks and individual dinosaur footprints provide a unique insight into the ancient palaeofauna, an opportunity to further explore the lives of polar dinosaurs.  In 2014, Everything Dinosaur wrote an article summarising some of the work undertaken by Dr Fiorillo and his colleagues as they interpreted a substantial number of duck-billed dinosaur tracks.  These trace fossils helped the researchers to better understand how these giant, herbivorous dinosaurs moved around in herds: Duck-Billed Dinosaurs Moved Around in Herds just like Elephants. Over the years, researchers from the Perot Museum of Nature and Science have made a very important contribution to research into dinosaur populations that lived (and seemed to thrive) at high northern latitudes.

Commenting on the significance of their work, Dr Fiorillo stated:

“At the start of every one of these expeditions, the adrenaline is pumping.  We are so excited to get back out there.  I fully expect that we will find dozens of footprints and we will learn a little bit more about the environment in which these dinosaurs lived.”

Nanuqsaurus hoglundi and Pachyrhinosaurus perotorum

Staff at the Perot Museum of Nature and Science, along with their collaborators from other institutions have been instrumental in helping to improve our understanding of the polar dinosaurs and the palaeoenvironment.  For example, a third species of Pachyrhinosaurus (P. perotorum) has been erected thanks to Alaskan fossil discoveries.

A Skeleton of the Horned Dinosaur Pachyrhinosaurus

Pachyrhinosaurus dinosaur exhibit.

A large horned dinosaur with a huge skull (Pachyrhinosaurus).

With all that plant food and the long summer days, Alaska might have been a paradise, albeit a chilly one for plant-eating dinosaurs.  However, they did have to contend with some particularly nasty predators, over-sized dromaeosaurids for example and perhaps, even more surprisingly a “polar” Tyrannosaur.  In 2006, a research team led by Dr Anthony Fiorillo and his colleague Dr Ronald Tykoski, also from the Perot Museum of Nature and Science discovered the fossils of a carnivorous dinosaur that was later named Nanuqsaurus hoglundi.

To read more about this fossil discovery: An Update on “Polar Bear Lizard”

We wish all field teams every success and we hope that they have a safe, rewarding and very satisfactory field season.

To read more about the discovery of Pachyrhinosaurus perotorum an article first published in 2011: A New Species of Pachyrhinosaurus is Announced

19 06, 2017

Volcanic Eruptions Heralded Dawn of the Dinosaurs

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

End-Triassic Mass Extinction Triggered by Volcanic Activity

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

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

The diverse fauna of Triassic Argentina.

Diverse fauna of north-western Argentina in the Triassic.

Picture Credit: Victor Leshyk

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

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

Life on Earth at the End of the Triassic

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

The Landscape of the Triassic

Triassic landscape.

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

Major Casualties of the end-Triassic Extinction Event

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

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

A Large and Abrupt Release of Carbon Dioxide

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

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

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

The Researchers Studied Sedimentary Deposits from Morocco

Late Triassic sediments (Morocco).

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

Picture Credit: Jessica Whiteside

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

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

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

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

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

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

11 06, 2017

How Did the Cleveland-Lloyd Dinosaur Quarry Get Its Name?

By | June 11th, 2017|Dinosaur Fans, Geology, Main Page, Photos/Pictures of Fossils|0 Comments

How Did the Cleveland-Lloyd Dinosaur Quarry Get Its Name?

After having published an article on a new theory explaining the mass death dinosaur assemblage preserved at the Cleveland-Lloyd fossil site in the Morrison Formation (Brushy Basin Member), we were sent an email asking how the Cleveland-Lloyd Dinosaur Quarry got its name if the site is a long way from Cleveland, Ohio?

Students Excavate the Bones of an Allosaurus from the Cleveland-Lloyd Dinosaur Quarry (Utah)

Working at Cleveland-Lloyd Dinosaur Quarry.

Students excavate the bones of an Allosaurus (Cleveland-Lloyd Dinosaur Quarry).

Picture Credit: Joe Peterson

The picture above shows Indiana University of Pennsylvania students Alex Patch, Heather Furlong and Josh Colastante working on the jumbled fossil bones of an Allosaurus at the Cleveland-Lloyd Dinosaur Quarry.

It is true, the fossil site, which represents the greatest concentration of Jurassic dinosaur fossils known to science, is a very long way from the city of Cleveland, but it is near the small town of Cleveland, Emery County, in Utah.  This famous fossil site was named in part, as it was close to the town of Cleveland.  The second part of the hyphenated name “Lloyd” is all to do with funding,

Map Showing Sites, Stratigraphic Section Line, and Regional Stratigraphy in Context of the San Rafael Swell

Location of the Cleveland-Lloyd Dinosaur Quarry.

Map showing sites, stratigraphic section line, and regional stratigraphy in context of the San Rafael Swell.

Picture Credit: PeerJ

In the picture above CLDQ marks the location of the Cleveland-Lloyd Dinosaur Quarry and JONS indicates the location of the nearby Johnsonville fossil site in Utah.  The inset map shows the location of the Cleveland-Lloyd Dinosaur Quarry in relation to the rest of the state of Utah.

To read the article: The Mystery of the Cleveland-Lloyd Dinosaur Quarry

Where Did the Lloyd Part of the Name Come From?

The site was first discovered in 1927, the first extensive excavations commenced in 1929, (University of Utah).  The siltstones were deposited in the Late Jurassic and the strata makes up part of the Brushy Basin Member at the northern end of the San Rafael Swell.  For the next decade, regular expeditions to the site were undertaken and these were funded, in the most part, by a lawyer from Philadelphia called Malcolm Lloyd.  This is how the famous dinosaur dig site came to be named.

The quarry is world-famous for its very high concentration of dinosaur bones.  The scattered remains of over seventy dinosaurs are believed to be present, representing nine dinosaur genera.  However, around two-thirds of all the bones are attributable to a single dinosaur taxon Allosaurus fragilis.  Most of the other bonebeds associated with the Morrison Formation contain a higher proportion of herbivorous dinosaurs. Furthermore, when the A. fragilis material is assessed over 85% of the fossils represent juveniles or sub-adults of the species.

Further exploration of this extremely fossil rich location is planned.

So, the site with the greatest concentration of Jurassic dinosaur bones known to science was named after a lawyer from Philadelphia and the nearest township.

Stegosaurus Fossil Material is Known from the Cleveland Lloyd Dinosaur Quarry

A skull of a Stegosaurus.

A Stegosaurus skull (Los Angeles Museum)

Picture Credit: Los Angeles Museum

18 05, 2017

Time to Question Where Life on Earth Started

By | May 18th, 2017|Dinosaur and Prehistoric Animal News Stories, Geology, Main Page|0 Comments

Earliest Evidence for Microbial Life on Land

Fossils which reputedly show evidence of microbial life in hot springs have been found in Australian rocks that date from 3.48 billion years ago.  The hot spring deposits found in the Pilbara region of Western Australia, have pushed back by some 580 million years, the earliest known existence of micro-organisms living in terrestrial freshwater habitats, albeit, in a very inhospitable place.  This discovery has reignited the debate as to where the first life on planet Earth might have originated.

Tiny Bubbles Preserved in the Rocks Could Demonstrate Early Microbial Life in Hot Springs

Evidence of early microbial life (Pilbara Craton).

Spherical bubbles preserved in 3.48 billion-year-old rocks in the Dresser Formation in the Pilbara Craton (Western Australia) provide evidence for early life having lived in ancient hot springs on land.  These bubbles could have been trapped in a sticky microbial film.

Picture Credit: University of New South Wales

The remote and very beautiful Pilbara region of Western Australia has exposures of extremely ancient sandstones, some of the oldest sedimentary rocks known.  These strata were formed in the Paleoarchean Era and it has been at the centre of research for evidence of micro-fossils and signs of very early life on Earth for a number of decades.  The Australian authorities are hoping to get UNESCO World Heritage status recognition for those parts of the Pilbara Craton that have provided evidence for very primitive, organic lifeforms.

To read an article from 2011 about micro-fossils preserved in Pilbara sandstones that indicate microbial life from 3.4 billion years ago: Are These the Oldest Fossils on Earth?

A Freshwater or a Marine Origin for Life on Earth?

The debate as to when life on Earth began has caused great controversy amongst scientists.  Resolving when the very first organisms evolved has proved extremely difficult, for example, back in the autumn of 2016, Everything Dinosaur published an article about an intriguing study of ancient Greenland rocks that might show evidence of microbial life, specifically stromatolites that existed in a shallow marine environment some 3.7 billion years ago.

For the article on the research on the Greenland rocks: 3.7 Billion-Year-Old Microbes?

What is equally as controversial, is where on Earth did life begin?

Writing in the academic journal “Nature Communications”, lead author, PhD student Tara Djokic (University of New South Wales) and her fellow researchers conclude that parts of the Pilbara Craton strata were formed from hot spring deposits and these rocks provide evidence that life may not have originated in a marine environment.

The Remote and Desolate Sandstone Ridges Represent Strata Formed Some 3.48 Billion Years Ago

A view of the remote Dresser Formation, Pilbara Craton (Western Australia).

Ridges in the ancient Dresser Formation in the Pilbara Craton of Western Australia that preserve ancient stromatolites and hot spring deposits.

Picture Credit: Kathleen Campbell

Extremophiles Living in Hot Springs

Scientists are aware that microbial life such as bacteria and those other prokaryotes – archaea are capable of surviving in very hostile environments.  The specialised archaea are often referred to as extremophiles as these organisms can tolerate and thrive in environments that would prove fatal to most other forms of life.  These extreme conditions include heat and high concentrations of noxious materials, the sort of conditions you can find in a geyser or hot spring.

Tara and her co-workers, which included Professors Martin Van Kranendonk, Malcolm Walter and Colin Ward (University of New South Wales) and Professor Kathleen Campbell (Auckland University), took samples from the ancient Dresser Formation in the Pilbara Craton and employed a variety of techniques to analyse their contents.  Microscopic sections of rock were prepared and a study of these samples led the team to conclude that they had found potential biological signatures and physical evidence of organic life preserved within the ancient strata.

Tara Djokic explained:

“Our exciting findings don’t just extend back the record of life living in hot springs by some three billion years, they indicate that life was inhabiting the land much earlier than previously thought, up to about 580 million years earlier.  This may have implications for an origin of life in freshwater hot springs on land, rather than the more widely discussed idea that life developed in the ocean and adapted to land later.”

Researchers Examining the Rocks

Looking for signs of ancient life in the Pilbara Craton.

Tara Djokic and co-author Professor Martin Van Kranendonk in the Pilbara in Western Australia looking for evidence of hot springs preserved in the strata.

Picture Credit: Kathleen Campbell

Charles Darwin’s “Warm Little Pond”

Where life originated has taxed academics, religious leaders and philosophers for centuries.  There are several theories, for example, the first organisms could have come to Earth via a comet, meteorite or asteroid impact, or life could have evolved here on Earth, perhaps in the deep sea around hydrothermal vents.  Other scientists have argued that life as we know it began on land, in the extreme environments of hot springs and geysers – the “warm little pond” as Charles Darwin is believed to have indicated.

The Discovery of Geyserite

Evidence of geyseyrite in the Dresser Formation.

A microscopic image of geyserite textures from the ancient Dresser Formation in the Pilbara Craton in Western Australia.  This shows that surface hot spring deposits once existed there 3.48 billion years ago.

Picture Credit: The University of New South Wales

Evidence of Geyserite

Microscopic polished slices revealed the presence of the mineral geyserite in the Dresser Formation deposits.  Geyserite (a form of silica), is associated with mineral deposits formed from hot springs or geysers, if extremophiles can survive in these harsh habitats today, then it is possible that they could have survived in very similar conditions on the primordial Earth.

Doctorate student Tara Djokic commented:

“The discovery of potential biological signatures in these ancient hot springs in Western Australia provides a geological perspective that may lend weight to a land-based origin of life.”

Researchers Examining the Waters Surrounding Hydrothermal Vents in New Zealand

Looking for signs of life in a hot spring.

Researchers examining the hot waters surrounding the hydrothermal vents at Rotokawa (New Zealand).

Picture Credit: Kathleen Campbell

Within the Pilbara hot spring deposits, the researchers also discovered stromatolites, layered rock structures created by communities of ancient microbes.  In addition, there were other signs of early life in the deposits, including fossilised micro-stromatolites, microbial palisade textures and well preserved bubbles that are inferred to have been trapped in sticky microbial slime to preserve the bubble shape.

Out of this World Implications – The Search for Life on Mars

The researchers comment that their work has major implications with the regards to the search for extraterrestrial life, particularly the search for life on Mars.  The rocks that make up the Pilbara Craton are about the same age as much of the crust on the red planet.  Ancient hot spring deposits on Mars could be a good place to search for evidence of long-extinct life.

NASA is currently planning a news Mars Rover mission (due to launch in 2020), one of the potential landing sites for the Mars land vehicle is the Columbia Hills.  Previous Mars expeditions have identified silicates that could have been formed in the presence of hot water from a thermal vent.  If evidence of ancient life on Earth, preserved in strata formed in a hot spring environment can be found, then such life processes may well have come about on Mars too and some evidence might be preserved in the ancient Martian rocks.

30 04, 2017

DNA from Ancient Hominins Discovered in Cave Sediments

By | April 30th, 2017|Dinosaur and Prehistoric Animal News Stories, Geology, Main Page, Palaeontological articles|0 Comments

DNA from Cave Sediments Reveals Ancient Human Occupants

Close to the Belgium town of Modave, there is a large cave.  It overlooks the Hoyoux River, a tributary of the Meuse and although no human bones have ever been found at this cave site, palaeoanthropologists are confident that it was once occupied by ancient humans as animal bones with stone tool cut marks are associated with the site.  The cave is called Trou Al’Wesse (“Wasp Cave” in Walloon) and thanks to a remarkable application of technology, scientists now know that some fifty thousand years ago, a Neanderthal relieved himself inside the cave.  That person’s urine and faeces may have long since decomposed but, left in the cave sediments were minute traces of his DNA.  Researchers have shown that they can find and identify such genetic traces of ancient humans, enabling them to test for the presence of ancient hominins even at sites where no human bones have been discovered.  In addition, the same technique can be used to map other mammalian fauna at these locations.  The scientists, including researchers from the Max Planck Institute for Evolutionary Anthropology (Leipzig, Germany) propose that this technique could become a standard tool in palaeoarchaeology.

Excavations at the site of El Sidrón, (Spain) – One of the Cave Sites in the Study

Searching for evidence of ancient hominin DNA.

Excavations at the site of El Sidrón, Spain.

Picture Credit: El Sidrón research team

The Secrets of Cave Soils and Sediments

Human remains are extremely rare and although scientists are aware of the existence of ancient hominins such as the Denisovans, they are only known from a handful of fossilised bones (literally, a single finger bone and a possible femur, plus some teeth).  However, cave soils and sediments themselves can provide genetic evidence in the form of tiny traces of ancient hominin DNA.  By examining cave soils and sediments and extracting genetic traces, scientists can gain a better understanding of the evolutionary history of humans, even if no bones or stone tools are present.

The research team members collected eighty-five sediment samples from seven caves in Europe and Russia that humans are known to have entered or even lived in during the Pleistocene Epoch.  The samples dated from between 14,000 and 550,000 years ago.  Using a refined DNA analysis technique, one that was originally designed to identify plant and animal DNA, the team were able to search specifically for hominin genetic evidence.

Commenting on the significance of this research, Matthias Meyer (Max Planck Institute for Evolutionary Anthropology) and co-author of the study published in the journal “Science” stated:

“We know that several components of sediments can bind DNA.  We therefore decided to investigate whether hominin DNA may survive in sediments at archaeological sites known to have been occupied by ancient hominins.”

Entrance to the Archaeological Site of Vindija Cave, Croatia

Searching for traces of ancient human DNA.

Entrance to the archaeological site of Vindija Cave, Croatia.

Picture Credit: Max Planck Institute for Evolutionary Anthropology/J.Krause

The picture above shows a view from the entrance of Vindija Cave in northern Croatia, one of the seven sites studied.  Analysis of microscopic amounts of mitochondrial DNA at the Vindija Cave location confirmed the presence of several large mammals including Cave Bears at this location.  The researchers found evidence of a total of twelve different mammalian families across the sites that were included in this study, including enigmatic, extinct species such as Woolly Mammoth, Woolly Rhinoceros and Cave Hyena.

 Mitochondrial DNA Helps Map the Presence of Large Mammals (Including Hominins)

DNA analysis identifies cave inhabitants.

DNA analysis helps map the presence of mammalian fauna in the absence of body fossils.

Picture Credit: Journal Science

Once animal DNA had been mapped the researchers turned their attention to identifying ancient human genetic traces within the samples.

Lead author of the research paper, PhD student Viviane Slon (Max Planck Institute for Evolutionary Anthropology), explained:

“From the preliminary results, we suspected that in most of our samples, DNA from other mammals was too abundant to detect small traces of human DNA.  We then switched strategies and started targeting specifically DNA fragments of human origin.”

In total, nine samples from four cave sites contained enough ancient hominin DNA to permit further analysis.  Of these, eight sediment samples contained Neanderthal mitochondrial DNA, either from one or multiple individuals, whilst one sample contained evidence of Denisovan DNA.  The majority of these samples were taken from archaeological layers or sites where no Neanderthal bones or teeth had been previously found.

A New, Important Tool for Palaeoanthropology

Svante Pääbo, another co-author of the paper and director of the Evolutionary Genetics department at the Max Planck Institute for Evolutionary Anthropology commented that the ability to retrieve ancient hominin DNA from sediments represented a significant advance in palaeoanthropology and archaeology.  The use of this technique could become a standard analytical procedure in future.

A Sample Ready for Testing

Testing cave sediments for ancient human DNA.

A cave sediment sample is prepared for DNA testing.

Picture Credit: Max Planck Institute for Evolutionary Anthropology/S. Tüpke

Even sediment samples that were stored at room temperature for years still yielded DNA.  Analyses of these and of freshly-excavated sediment samples recovered from archaeological sites where no human remains are found will shed light on these sites’ former occupants and our joint genetic history.

Everything Dinosaur acknowledges the contribution of the Max Planck Institute for Evolutionary Anthropology in the compilation of this article.

25 04, 2017

Fossil Fungus Discovery Rocks Geology and Biology

By | April 25th, 2017|Dinosaur and Prehistoric Animal News Stories, Geology, Main Page|0 Comments

Fungus-Like Forms Found in 2.4 Billion-Year-Old Rocks

An international team of researchers, including scientists from the Swedish Museum of Natural History, Stockholm University and the University of California, have identified microscopic structures found in tiny bubbles and pores in ancient basalt that resemble fungi.  If these fungi-like structures are indeed Palaeoproterozoic remnants of members of the Kingdom Fungi, then this discovery could push back the date for the oldest fungi by between 1,000 and 2,000 million years.

Thin Sections of the Ongeluk Basalt Showing Evidence of Mycelium

Ancient fungi in ancient marine rocks.

Views of treated micro-slides showing potential mycelium.

Picture Credit: Nature, Ecology and Evolution (Swedish Museum of Natural History)

Over the last few decades, cores drilled deep into the seabed and other exploration techniques utilised to build knowledge of the biota present in oceanic sediments and crustal rocks have revealed that many different types of fungi thrive in these environments.  The fossil record of fungi is extremely intermittent and the identification of possible fungal remnants in the fossil record is controversial to say the least, (look up the Devonian Prototaxites for further details).  However, many geologists and palaeontologists have proposed that the fossil record for such extremophiles does date back to at least the Early Devonian, a time when primitive plants and fungi were beginning to diversify and radiate in terrestrial environments.  Drill cores taken from the Ongeluk Formation in South Africa show microscopic signs of filamentous fossils in vesicles and fractures.  The filaments form mycelium-like structures growing from a basal film attached to the internal rock surfaces and they look very similar to the structures attributed to fungi found in rocks which are hundreds of millions of years younger.

The Ongeluk fossils, are two to three times older than current age estimates of the Kingdom Fungi. Unless they represent an unknown branch of fungus-like organisms, which are new to science, the fossils imply that the fungal clade is considerably older than previously thought, and that fungal origin and early evolution may lie in the deep ocean rather than in terrestrial environments.

The Ongeluk discovery suggests that life has inhabited deep sea oceanic rocks for more than 2.4 billion years.

The Impact on Eukaryotes

The jumbles of tangled threads, which are only a few microns across, if they are fungi, belong to the Eukaryote Domain (Eukarya), a diverse group containing at least four Phyla and some 6,000 species, (fungi include the familiar mushrooms and toadstools plus yeasts and moulds).  Eukaryotes have cells that are complex with a distinct nucleus protected by a membrane.  Animals and plants are also Eukaryotes and the discovery of such ancient life forms, preserved in ocean rocks has implications for the early history of the whole of the Eukarya, as well as potentially, pushing back the date for the evolution of the first fungi to around 2.4 billion-years-ago.

Commenting on the significance of this research, lead author of the scientific paper, Stefan Bengtson (Department of Palaeobiology and Nordic Center for Earth Evolution, Swedish Museum of Natural History), stated:

“The deep biosphere [where the fossils were found] represents a large portion of the Earth, but we know very little about its biology and even less about its evolutionary history.”

The Professor added, that there was a clear possibility that these fossils represent the world’s oldest fossil fungi, much older than anything else known to the scientific community.

He went onto state:

“If they are not fungi, they are probably an extinct branch of Eukaryotes or even giant Prokaryotes.”

The Impact on the Hunt for Extraterrestrial Life

A spokesperson from Everything Dinosaur commented that if these fossils represent fungi occupying gas bubbles in lava that form rocks in the seabed, it demonstrates how organisms can survive in extreme habitats.  Tests have indicated that the rocks where the structures were found could have been as hot as 250 degrees Celsius and these lifeforms would have had to survive without sunlight and cope with immense pressure.  If the fossil record for such fungi is extended by billions of years on our own planet, then it raises the intriguing possibility that such life forms may well have evolved and if they did, they probably still exist in extreme environments elsewhere in our solar system.  The watery environment trapped under the ice of Saturn’s moon Enceladus could harbour the sort of conditions where organisms such as these could still thrive.

Saturn’s Icy Moon Enceladus – Perhaps Home to Marine Crustal Fungi?

Saturn's icy moon Enceladus.

A view of the moon Enceladus – could this icy world harbour fungi?

Picture Credit: NASA

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