Category: Geology

A Sixth Mass Extinction Event?

Capitanian Extinction Event – Suggested by Northern Hemisphere Study

A team of geologists have published a paper in the prestigious Geological Society of America Bulletin postulating that there was a major global extinction event that took place in the Permian geological period.  To be more precise the evidence for the extinction can be found in rocks laid down approximately 262 million years ago (the Capitanian stage of the Guadalupian epoch of the Permian).  The idea that there was a major extinction event amongst both marine and terrestrial organisms in the Middle Permian is not new.  Studies of the diversification of marine invertebrates recorded in Mid Permian strata from lower latitudes indicated that several families of mollusc and Brachiopod had died out during this time in Earth’s history.  It had been thought that global cooling had resulted in the loss of so many types of marine animal from the tropics.  However, this new study indicates that the Middle Permian extinction is manifested in the fossil record preserved at higher latitudes.

To assess the extent of the extinction, the research team, led by Dr. David Bond (University of Hull) travelled to the remote Norwegian island of Spitsbergen to explore the Kapp Starostin Formation, a layer of marine strata that is up to four hundred metres thick.  These rocks were laid down over a period of around 27 million years and cover the crucial period of the Guadalupian epoch.   By assessing the number and type of Brachiopod fossils found in the rock layers, the scientists were able to demonstrate that there were two severe extinctions amongst Brachiopods in northern latitudes in the Middle to Late Permian.  These extinction events are separated by a recovery phase, a time when the diversity of Brachiopods increased.

Many Rhynchonellid Brachiopod Fossils Found Together

Study suggests global mass extinction event in the Permian.

Study suggests global mass extinction event in the Permian.

Picture Credit: Everything Dinosaur

Brachiopods, superficially resemble shelled molluscs like clams and mussels, but they have a very different body plan.   They are not closely related to the Mollusca and the Brachiopoda is an entirely separate phylum.  These little creatures first evolved in the Cambrian and they are still around today.  Most can be found in deep water and they are benthic (live on the sea floor), they are not found in freshwater.  There are more than a dozen or so species to be found in the waters surrounding the British Isles.  Brachiopods are sometimes called “lamp shells” as some of them resemble the shape of oil lamps used by the Romans.  Shells are usually made from calcium carbonate, but some form phosphatic shells.  The shells which protect the soft tissues consist of two parts (valves), one part is always bigger than the other part.  They are often the commonest fossil to be found in Palaeozoic marine limestones that represent shallow water deposits, as a result there are a number of Brachiopod biostratification zones.

An Illustration of a Group of Brachiopods

Brachiopods anchored themselves securely using a pedicle.

Brachiopods anchored themselves securely using a pedicle.

Picture Credit: Everything Dinosaur

Strontium isotope analysis coupled with examination of trace metals and magnetic polarity preserved within the strata, correlated the time of the formation of the layers that show a distinct decline in Brachiopod diversity to about 262 million years ago (Capitanian stage).  Older rocks show that Brachiopods dominated the fossil record, but there is an 87% fall in fossil Brachiopod diversity in the middle of the Capitanian-aged rocks.  Younger rocks do have preserved remains of Brachiopods but they are different from the ones in the Capitanian strata, in addition, the younger rocks show a change in the fauna, there are many more bivalves (molluscs) preserved as fossils.   This suggests that there was a catastrophic event that lasted tens of thousands of years which led to a dramatic change in the benthic  invertebrate populations, as recorded by the fossil evidence.  The research team visited Spitsbergen three times to conduct the research from 2011 to 2013, working in the month of July, taking advantage of the 24 hours of daylight available and the slightly warmer weather.  Polar bears were still a danger and the expedition had to be on the look out in case a curious bear came into their camp.

The existence of a separate and distinct global extinction event around 262 million years ago, remains controversial.  Just a few million years ago, the biggest mass extinction event known occurred, resulting in the loss of something like 96% of all sea-dwelling creatures.  The event is known as the end Permian mass extinction.   The vast majority of the invertebrates recorded in the rocks after the Capitanian event became extinct.  The authors of the paper, published in the Geological Society of America Bulletin, suggest that their research shows that the Capitanian extinction event devastated fauna in both the tropics and in northern latitudes.  They conclude that this extinction was not limited to the warmer areas of the planet but much more wider ranging, deserving the status of a global mass extinction event.

What Caused this Extinction?

Molluscs and Brachiopods need calcium to make their shells (most of them), Dr. Bond believes massive volcanic eruptions in what is now the Chinese Province of Sichuan released huge amounts of carbon dioxide which in turn, acidified the oceans locking up the calcium.  In addition, depletion of oxygen on the sea floor may also have contributed to the extinction event.

Today, April 22nd is designated “Earth Day”, a day in which we recognise the plight of our planet, issues like global warming, extinction and loss of habitat.  It is apt for us to be considering the evidence for a sixth mass extinction event recorded in the Phanerozoic Eon (visible life).

Scientists Set Out to Explore Chicxulub Impact Crater

Impact Crater from Dinosaur Extinction Event to be Explored

Plans are in place for a team of international researchers to drill into the seabed off the Yucatan peninsula (Mexico), so that they can explore the composition and structure of the Chicxulub impact crater, the site where around 66 million years ago, a huge rock from space crashed into our planet.  The impact was so immense that the devastation and climate change events that this collision caused may well have resulted in (or at least assisted with), the extinction of the dinosaurs.  The scientists intend to drill into the crater, which is buried under sediments over fifteen hundred metres thick and study the elevated sections called the “peak ring”.  These rocks were forced up by the impact and form the boundary of the impact site, these topographically elevated rings are present in nearly all extraterrestrial impacts and the scientists hope to learn more about the Chicxulub impact itself as well as gaining a better understanding of such impact events and their effect on our our rocky planet.

An International Research Team Plan to Explore the Chicxulub Impact Crater

The end of the Age of Dinosaurs.

The end of the Age of Dinosaurs.

The Cretaceous mass extinction event is one of the most researched areas of science.  Improving our knowledge of how the climate change affected life in the past is helping to shape current policies as our planet experiences a period of exceptional warming.  Whether or not the extraterrestrial impact was the cause of the extinction of about 70% of terrestrial life, marking the end of the Age of Dinosaurs, is still debated.  Recent research from Glasgow University dates the impact at approximately 66,038,000 years ago +/- 11,000 years (margin of error).  This date according to many scientists is about 300,000 years before the Dinosauria extinction.  Whether the impact is the single cause, or whether it contributed to the mass extinction which occurred as a result of a number of factors remains when one of the hottest topics in palaeontology.

It was father and son team Luis and Walter Alvarez, who in 1980, publicised the discovery of a layer of clay with high levels of the rare Earth element iridium which mark the Cretaceous/Tertiary boundary (the K-T boundary).  They argued that the iridium was deposited as a result of an impact event where a meteorite or some other rocky body crashed into our planet.  The discovery of the Chicxulub crater that dated from the end of the Cretaceous provided “the smoking gun” evidence that just such an event had occurred.

The scientists involved in this new research project gathered in the city of Merida (Mexico) last week.  Merida, is within the 125 mile wide impact site that marks the Chicxulub event.  Scientists have estimated that the extraterrestrial object, perhaps an asteroid or even a comet, was at least six miles wide and it was travelling about eight times faster than a bullet when it hit the Earth.  About £6 million GBP has been set aside for funding, approved by the European Consortium of Ocean Research Drilling (ECORD).  Sean Gulick, who holds many academic posts including Associate Professor at the UT Jackson School of Geosciences, is part of the research team and has spent many years studying the geology of the Yucatan peninsula.  He hopes to acquire samples from the crater in a bid to learn more about the impact and its consequences.

Explaining the purpose behind the planned expedition, which is due to start next year, Sean stated:

“What are the peaks made of?  What can they tell us about the fundamental processes of these impacts, which is this dominant planetary resurfacing phenomena?”

The Associate Professor and long-time co-worker, Professor Joanna Morgan (Imperial College, London) have collaborated on a number of research projects exploring the Chicxulub impact crater, to read more about their research and earlier explorations of the geology of the Yucatan peninsula, click the link below:

To read more about this earlier research by the University of Texas: Getting to the Bottom of the Chicxulub Crater

A Geophysical Map Outlining the Impact Crater and the Crater Peaks

A geophysical map of the impact crater.

A geophysical map of the impact crater.

Picture Credit: NASA

The picture above shows a colour coded geophysical gravity map of the Yucatan peninsula.  The white dots represent “Cenotes”, these are sink holes which were formed as a result of the impact event.

The international research team are keen to explore the traces of microscopic life that may have lived inside the peak rocks of the crater.  The geophysical maps of the region indicate that these rocks are porous and they may have acted as miniature environments for types of extremophiles to thrive in the hot, chemically enriched area surrounding the crater.  In addition, core samples should provide evidence of the earliest recovery of marine life after the extraterrestrial impact, providing scientists with an idea about how life on Earth bounces back from such cataclysmic events.

Commenting on the search for evidence of life, Associate Professor Gulick stated:

“The sediments that filled in the crater should have the record for organisms living on the sea floor and in the water that were there for the first after the mass extinction event.  The hope is, we can watch life come back.”

Working from an offshore platform, the expedition is likely to last eight weeks and the cores taken will be the first to be extracted from the impact site.  The first papers on the analysis of these core samples are expected at the end of next year, we at Everything Dinosaur, look forward to this analysis of the “Alvarez smoking gun”.

William Smith Map – Re-discovered

Founding Father of Geology and His Remarkable Map

One of the very first editions of arguably one of the most significant maps in the history of the study of our planet has been re-discovered.  A pristine copy of William Smith’s 1815 map of the geology of England, Wales and parts of Scotland has been found in the archives of the Geological Society (London).  It seems that the map was placed in storage, carefully sealed inside a leather wallet but just where in the vast archive it was stored had not been recorded.  Ironic really, when you consider the dedication and attention to detail shown by Smith, the son of a blacksmith who so meticulously mapped the strata of most of the British Isles.

The archives of the Geological Society are vast, after all, it is the oldest body of its kind in the world (founded in 1807).  This year marks the bicentenary of the publication of William Smith’s great geological survey, only about 370 or thereabouts were ever produced and with this re-discovery, it is estimated that at least seventy are still in existence, not bad considering this map first went into production in the same year as the battle of Waterloo.  It is believed that this particular copy last saw the light of day around forty years ago.

Indexing the map, which comprises of fifteen sections would not have been easy.  It was customary in Georgian times to use very long titles for scientific publications, a trend that in some academic institutions still exists today.  Try cataloguing a map with the catchy title of:

“A  Delineation of the Strata of England and Wales with part of Scotland, exhibiting the collieries and mines, the marshes and fen lands originally overflowed by the sea, and the varieties of soil according to the variations in the substrata, illustrated by the most descriptive names by W. Smith.”

It is thought that William Smith, nick-named “strata-Smith” by his contemporaries spent fifteen years travelling the United Kingdom and carefully recording the rock formations exposed on the surface of the land.  His map when published, helped land owners and mining companies exploit this nation’s natural resources as the map helped surveyors identify potential areas for drainage, sites for new building work and most importantly which layers of strata indicated the presence of coal seams nearby.

Commenting on the discovery, John Henry (Chairman of the Geological Society’s History of Geology Group), stated:

“It just wasn’t where people expected it to be.  I guess the person who put it away knew where it was, but then they left and that was it, it became lost.”

Having been hidden away in the archives the map, which was printed from copper plate engravings with the details painted in with water colours, has not faded and the colours depicted are as vivid today as when the map was first completed.  Archivists are puzzling over just what number in the sequence of maps produced might this copy be?  There is the exquisite hand finished painting with the lower edge of each formation saturated and then the paint is faded to indicate the formation’s edge, a technique used by Smith to make his maps easier to read, but the map itself, unlike later editions, has no serial number.

Geologists are aware that the very first maps produced were not numbered.  Another clue as to just when this map was made can be seen in how the geology of the Isle of Wight is depicted.  Over the production period of Smith’s map, the way in which the geology of the Isle of Wight was shown changed several times.  This map shows a very early effort to map the geology of the island.  All this suggests that this particular example of cartography might be amongst the first dozen or so ever produced.

A Clue to the Age of the Map – The Strata of the Isle of Wight

The Isle of Wight illustrations suggests an early print.

The Isle of Wight illustrations suggests an early print.

Picture Credit: The Geological Society (London)

The Geological Society has had the map fully restored and digitised.  As from today, it will be available to view on line on the Geological Society’s website.  This copy of the map itself will be stored back in the archives, this time properly catalogued.  A paper copy of the “Smith map” will be put on display in Burlington House, (London) the home of the Geological Society.

The Beautifully Illustrated Geological Map of the Cotswolds (William Smith)

Beautifully illustrated geological map.

Beautifully illustrated geological map.

Picture Credit: The Geological Society (London)

To see the map and other important geological images on line: The Picture Library of the Geological Society

Now, we at Everything Dinosaur don’t want to be cynical but today, March 23rd, is the anniversary of the birth of William Smith.  He was born on this day in 1769 in the county of Oxfordshire.  We think the timing of this announcement regarding the re-discovery has a lot to do with publicising an event taking place later on today, when Sir David Attenborough will be unveiling a plaque in tribute to the “Father of English Geology” at his former London residence – 15 Buckingham Street.  During his life, as William Smith strived to forge a reputation amongst academics, his lowly beginnings as the son of a blacksmith meant that his views and findings were often disregarded by those who perceived themselves to be of a higher class.  Class distinctions blighted the lives of many pioneers in geology and palaeontology during the Georgian and Victorian times.  However, William Smith and his contribution to our understanding of the world is now recognised and his map of England, Wales and parts of Scotland remains one of the most significant maps ever produced.

Why was the Map So Important?

The map certainly helped landowners and that part of Georgian society that owned mines.  It helped stoke (literally) the Industrial Revolution but it did something else, as William Smith traversed the British Isles making his map, he noticed that certain types of sedimentary rock, although far apart contained the same types of fossils.  We shall let John Henry explain just how significant this realisation was:

“The concept which enabled him to do the mapping and that drove him along almost obsessively was this realisation that specific fossils were unique to a specific stratum, and that you knew where you were in a sequence if you could see what the fossils were.  That was the breakthrough.  People had been collecting them for a long time and naming them in the Linnaean way, but without any real idea that they were in a sequence.  But Smith knew it.”

Smith explored the deep excavations taking place as canals and other major works were being constructed and found that he could correlate apparently dissimilar and geographically dispersed strata based on the fact that they contained similar fossils.  Going up through the strata, William Smith observed a succession of different fossils and proposed that each stage of this succession represented a specific period in the history of the Earth.  This is termed the “principle of faunal succession”.  In this way, the relative age of rocks could be determined and the types of fossils that characterise strata led to the concept of biostratigraphy.  Smith developed and built on the idea of a Law of Superposition, postulated by the great scientist Nicolas (sometimes spelled as Nicolaus), Steno in the 17th Century.

To read more about the work of Nicolas Steno: Google Doodle Commemorates Nicolas Steno

The 1815 Geological Map of England, Wales and Parts of Scotland

Can you see the geology in your part of the world?

Can you see the geology in your part of the world?

Picture Credit: The Geological Society (London)

Originally produced as a map in fifteen sheet sections, the geological map of the British Isles (most of it) measures approximately 180 cm by 250 cm.  We at Everything Dinosaur, don’t know why northern Scotland was not mapped by Smith, we suspect it was much more difficult to travel the highlands and islands of northern Scotland and during the early 19th Century, there was simply not the demand for detailed geological maps of that part of the British Isles.

Spring Low Tides Uncover French Dinosaur Footprints

The Dinosaur Footprints at Veillon Beach (Vendée)

The low tides brought about as a result of the spring equinox has exposed a remarkable series of Early Jurassic trace fossils, giving residents of the town of Talmont-Saint-Hilaire the chance to go “Walking with Dinosaurs”.  The exceptional low tides on France’s North Atlantic coast have revealed 200 million year old footprints as well as ripple marks preserved in the mudstone and sandstone which were laid down at the very beginning of the Jurassic (Hettangian faunal stage).  The site represents an estuary, or shallow bay area and this was criss-crossed by many different types of dinosaurs.  Hundreds of footprints have been recorded, a large number have been removed to prevent further damage by erosion, but at very low tides, especially in the spring when the seaweed and algae growth is not extensive, many three-toed prints can still be seen.

“Walking with Dinosaurs” – Some of the Footprints Revealed at Low Tide

One of the many three-toed prints that can be seen at very low tide.

One of the many three-toed prints that can be seen at very low tide.

Picture Credit: GeoWiki

The site was discovered in 1963 by a local engineer and chemist Gilbert Bessonnat, but it was not until March 1965 when a team of French palaeontologists mapped the area in earnest that the full significance of the location was revealed.  The mapping project begun on March 19th that year, taking advantage of the very low tide associated with the spring equinox, allowed the scientists to discover what has turned out to be the largest single concentration of dinosaur ichnofauna in the whole of France.  Dinosaur trace fossils from the Lower Jurassic are exceptionally rare, the site is protected and no fossil collecting is allowed.  After all, the sandstones and mudstones preserved here record terrestrial life shortly after the End Triassic extinction event, those footprints were made some fifty million years before the likes of Stegosaurus and Diplodocus and other iconic Jurassic dinosaurs roamed the Earth.

In all, about a dozen different ichnospecies have been identified, including large and small Theropods.  Some footprints may not represent dinosaurs, for example, some trace fossils have been assigned to the Order Rauisuchia and ascribed to the Postosuchus genus (a type of ancient, terrestrial Crocodylomorph).  Ichnospecies associated with the site include: Eubrontes veillonensis tentatively described as a Megalosaur, Talmontopus tersi which could be a bipedal Ornithischian dinosaur and several dinosaurs assigned to the coelophysids (ichnogenus Grallator).

It seems that low tides on the North Atlantic coast of France, are providing scientists with a unique opportunity to learn about life in the Early Jurassic, well at least over the spring and autumn equinox anyway.

A Close Up of One of the Many Hundreds of Dinosaur Footprints Preserved at the Site

This print has been assigned to the ichnospecies Eubrontes.

This print has been assigned to the ichnospecies Eubrontes.

Picture Credit: GeoWiki

The Very Complicated Human Family Tree

New Research and New Discoveries Shed Light on our Ancestry

If anyone has had an opportunity to trace their family tree, then they know that given the wealth of data around today, a few clicks of the keyboard can provide a great deal of information about your family.  However, when it comes to tracing the origins of the “human family”, the evolution of our own species, then things are much more tricky.  New research published today in the journal “Nature” is helping to unravel the complicated journey that hominins have taken, a journey that eventually saw the emergence of our species, Homo sapiens sometime around 220,000 years ago.

Using a fossilised very human-like partial jawbone found at Ledi-Geraru, (Ethiopia), which has been dated to around 2.8 million years ago, in addition with already described material, an international team of scientists have reconstructed the skull of the early hominin Homo habilis (handy man) and looked at the ancestry of this species.  The research team included scientists from the University College London, in collaboration with the National Museums of Tanzania and the Max Planck Institute for Evolutionary Anthropology (Leipzig, Germany).  This new research helps to establish the human lineage and to determine what makes H. habilis so distinctive from the early Australopithecines such as the famous “Lucy” fossil –  A. afarensis which ironically, was discovered not too far from where the 2.8 million year old hominin lower jaw was found.  However, the fossils of “Lucy” are much older.  The partial skeleton of “Lucy” has been dated to around 3.2 million years ago.

To read more about an exhibition that features the remarkable preserved remains of “Lucy”: Pictures from an Exhibition

The first fossils of “handy man”, Homo habilis were described in 1964.  They consisted of a distorted lower jaw, hand bones and a highly fragmented braincase, all representing the bones of a single individual.  These fossils were catalogued as Olduvai hominin (OH7).   The rarity of early human bones, along with the very distorted remains associated with the earliest evidence of H. habilis made determining the unique characteristics and features of this species extremely difficult.  However, this research team utilised state-of-the-art computerised tomography and sophisticated computer modelling to unscramble the distorted remains and to piece together a reconstruction of the skull and jaws of Homo habilis.

The question that has puzzled palaeoanthropologists since the scientific description of Homo habilis and the subsequent discovery of more Australopithecine fossil remains was, could the likes of “Lucy” have evolved into the very first human-like creatures? Professor Brian Villmoare (University of Nevada), believes that the discovery of this 2.8 million year old jaw bone, complete with five teeth helps to confirm this hypothesis.

The Fossilised Jaw Bone (2.8 million years old)

Something for the palaeoanthropologists to get their teeth into.

Something for the palaeoanthropologists to get their teeth into.

Picture Credit: Brian Villmoare (University of Nevada)

The problem is this, the fossil record between the time period when “Lucy” and her kin were alive and the emergence of Homo erectus (with its relatively large brain and human-like body proportions), some two million years ago, is extremely sparse.  What has been found, is also very fragmentary, making tracing evolutionary links difficult.  The ancient human-like jawbone is highly significant.  The molar teeth are much smaller and less robust than those of other hominins known from the fossil record.  It is the size of the jaws and the teeth wherein that helps scientists to distinguish more human-like species from those which are more ape-like.

Commenting on the significance of this fossil find, scientists have stated that this new discovery pushes back the human evolutionary line by some 400,000 years or so.  The fossilised jawbone with its mix of primitive and more advanced traits makes it a candidate for a transitional species between the Australopithecines and the human family tree.

The Digital Reconstruction of the Skull and Jaws of Homo Habilis

The digitally mapped and reconstructed skull of H. habilis.

The digitally mapped and reconstructed skull of H. habilis.

Picture Credit: University College London

The “handy man” fossil material having undergone its computer modelling reveals new information about the jaw shape.  The computer having reassembled the distorted jaw described in 1964, to provide a more accurate reflection of the living bone.  The research published in “Nature” suggests that Homo habilis has older evolutionary roots than previously thought.  This research supports the idea that many different types of Homo species existed in Africa between 2.1 and 1.6 million years ago.  Climate change, leading to a much drier, deforested habitat may have led to a spurt in evolutionary experimentation as species adapted to the new environment and exploited new niches in the changing ecosystem.  The modelled lower jaw reveals primitive traits such as seen in Australopithecine fossil material, but it also has more advanced features, distinguishing H. habilis from its contemporary Homo rudolfensis.

The potential transitional link between hominins and Australopithecines remained elusive until the University of Nevada discovery of the 2.8 million year old jawbone.  The fossil, known as LD 350-1 is an excellent candidate for the ancestor of Homo habilis and other early hominins.

 Commenting on the fossil jawbone discovery, Dr. Villmoare stated:

“LD 350-1 reveals that many of the anatomical patterns we see in two million year old Homo were established much earlier in the evolution of the genus.  At 2.8 million years ago we see relatively evolved Homo traits in combination with other, much more primitive anatomical features, a result that is particularly interesting in light of the shape of the OH7 reconstruction.”

A Trip to the Bathonian

The Bathonian Stage of the Middle Jurassic

Just like a book is divided up into chapters so geological time is divided up into a series of units.  There are Eons, Eras, Periods, Epochs, and faunal stages, these are the typical units of division when it comes to exploring the geological timescale.  A point reinforced when a team member from Everything Dinosaur made a visit to Somerset recently.

Descending order of size for the units of the geological timescale (deep time):

  • Eon for example, the Phanerozoic (visible life) from 542 mya to the present day.
  • Era for example, the Mesozoic, from 251 mya to 65 mya) or thereabouts.
  • Period, for example, the Jurassic (199 mya to 145 mya) approximately.
  • Epochs, for example, the Middle Jurassic (175 mya -161 mya) approximately.
  • Stages or Ages such as the Bathonian (167.7 mya to 164.7 mya) approximately.

We mention this, as whilst working with Year 6 children and their teachers in the Bath area, we explained that the limestone rocks in their part of the world, were used as building materials and have been quarried for centuries.  Many of the buildings around the school, and the walls of the school were constructed using these limestones.  These limestones are the preserved remains of the shells of ancient sea creatures, that lived during the Jurassic.  The Bathonian faunal stage was named after the spa town of Bath and the limestone found in this part of south-western England.  It was included in scientific literature as early as 1843.  A number of Ammonite species are recognised from this Middle Jurassic strata and they help to provide a biostratigraphic profile and assist with relative ageing of the rocks.  Bathonian rocks have provided a number of dinosaur fossil remains including Sauropods, armoured dinosaurs, meat-eaters and even a distant relative of the most famous dinosaur of all Tyrannosaurus rex (Proceratosaurus).

Typical Bathonian Limestones used as Local Building Materials

A faunal stage of the Middle Jurassic named after the spa town of Bath.

A faunal stage of the Middle Jurassic named after the spa town of Bath.

It was a nice moment to ask the school children did they want to see something from the Jurassic?  When they all said yes, we simply asked them to look out of the window.

Fossil Hunting Down Under

Local Fossil Hunters Get the Chance to Work with Professionals

On Sunday 22nd February amateur fossil hunters will get the chance to visit one of the state of Victoria’s most important fossil sites and get advice from leading palaeontologists.  Museum Victoria is holding a special event at the historic Beaumaris Bay fossil site.  The sandstone cliffs preserve evidence of marine fauna from Australia’s prehistoric past.  Many types of shark teeth have been discovered along with the fossilised bones of a number of marine vertebrates.

The day will involve talks from professional fossil hunters Dr Erich Fitzgerald (Museum Victoria), Professor Tim Flannery and Professor John Buckeridge of RMIT University (Melbourne).  Local amateur fossil hunters will also have the chance to have their finds identified by these experts.

Local Fossil Collectors and Professional Scientists Working Together in Beaumaris Bay

Fossil site has open day.

Fossil site has open day.

Picture Credit: David Hastie/Museum Victoria

Commenting on the special, interactive day dedicated to fossil collecting, Dr Erich Fitzgerald (Senior Curator of Vertebrate Palaeontology, Museum Victoria) stated:

“There is simply no better place to find fossils in Melbourne than Beaumaris.  They have helped us paint a rich portrait of what Victoria was like millions of years ago.  The abundance of fossils of large marine animals, especially sharks and whales, suggests that between 6 and 5 million years ago the coastal waters of Victoria were far richer in nutrients than they are today.”

But fossil hunting is not just for professional scientists, as most professional scientists are happy to admit.  Fossils are being eroded out of the sandstone cliffs all the time and if it was not for the dedicated community of local fossil hunters, many potentially significant finds could be severely abraided by wave action or lost all together before a professional palaeontologist got the chance to explore the area.

Dr. Fitzgerald added:

“In Museum Victoria’s collection there are thousands of stunning fossils from Beaumaris, many collected by enthusiastic members of the public with a keen interest in palaeontology.  The public can provide an extremely valuable insight from their fossil discoveries, which would potentially not have been uncovered otherwise.”

Back in 2012, Everything Dinosaur reported on the discovery of a fossilised leg bone found in the Beaumaris Bay area that was identified as belonging to a new genus of “toothed” marine bird.

To read more about this discovery: Giant “Toothed” Birds Once Soared over Southern Australia

With such a huge country to explore, Everything Dinosaur has predicted on numerous occasions that this continent will provide palaeontologists with a number of new fossil discoveries, even new types of dinosaur.  Members of the public who participate in sensible, careful fossil hunting and who are sensitive to the environment and wish to work within the fossil hunting code can make a huge contribution to the Earth sciences.

Everything Dinosaur acknowledges the support of Museum Victoria in the preparation of this article.

Casting Doubts on Global Firestorms

Extraterrestrial Impact May Not Have Caused Global Firestorms

The debate over the consequences of the extraterrestrial impact that took place around sixty-six million years ago continues with the publication of pioneering new research that investigates whether or not the Yucatan impact caused extensive firestorms on a global scale.  It is now widely believed that at least one huge object from outer space crashed into Earth which very probably contributed to the mass extinction event that marks the end of the Cretaceous.  This is perhaps the most famous of all the mass extinction events recorded in the Phanerozoic fossil record, as no significant quantities of dinosaur fossils are found in younger strata.  The end Cretaceous mass extinction event saw the demise of the Dinosauria, the Pterosaurs, most of the marine reptiles and a number of other significant casualties.  It had been thought  that a consequence of the impact was a series of huge fires that ravaged the Earth, destroying much of the plant-life on the planet.  Plenty of evidence for this catastrophic event has been cited, for example, large amounts of carbon preserved in strata at the K-T boundary, believed to be the preserved remains of such conflagrations.

In 2013, for example Everything Dinosaur published an article on this blog citing research which suggested that intense heat in the atmosphere did indeed cause huge fires: Cretaceous Mass Extinction Study Provides Evidence of Global Firestorm

Scientists have also recorded evidence of a “fern spike” that occurred immediately after the extinction event.  Large numbers of fossilised fern spores have been recorded (microfossils), in contrast to a very low level of other plant remains such as pollen from flowering plants being recorded.  Ferns are quick to re-colonise an area after a devastating volcanic eruption.  The “fern spike” data was taken as supporting evidence for the massive destruction of much of the planet’s green matter.

To read more about the “fern spike” research: Humble Ferns – Evidence to Support the Impact Theory

Did the Extraterrestrial Impact Cause Global Firestorms?

Cataclysmic impact event.

Cataclysmic impact event, but was there a global firestorm?

Picture Credit: Don Davis commissioned by NASA

However, a team of UK based researchers (University of Exeter, Imperial College London and the University of Edinburgh), have challenged the idea of world-wide fires.  The scientists recreated the massive energy released from the impact event and they found that the blistering heat near the impact site was too short-lived to ignite living plants.  The scientists conducted a series of experiments using pulses of heat and writing in the Journal of the Geological Society, the team conclude that close to the actual impact, the heat wave would have lasted less than a minute, too short a time to set fire to living plants.  However, using computer models they discovered that the effects of the blast would have been felt as far away as New Zealand, some 12,000 kilometres from the site of the explosion.  The further away from the blast centre, the less intent the heat wave, but it would have been longer lasting.  In New Zealand, the heat blast would have lasted for around seven minutes, long enough to ignite living plant material.

Experiments conducted suggest that dry and dead plant matter could be set alight, but live plants such as conifer needles were not ignited.

Having a Blast with Heat Wave Experiments

Global firestorm study.

Global firestorm study.

Picture Credit: University of Exeter

The picture above shows the fire propagation apparatus recreating the impact induced thermal pulse at the Cretaceous/Palaeogene (K-T boundary).  Halogen lamps are delivering the intense, thermal radiation.

Commenting on the study, Dr. Claire Belcher (Earth System Science group in Geography at the University of Exeter) stated:

“By combining computer simulations of the impact with methods from engineering we have been able to recreate the enormous heat of the impact in the laboratory.  This has shown us that the heat was more likely to severely affect ecosystems a long distance away, such that forests in New Zealand would have had more chance of suffering major wildfires than forests in North America that were close to the impact.  This flips our understanding of the effects of the impact on its head and means that palaeontologists may need to look for new clues from fossils found a long way from the impact to better understand the mass extinction event.”

Fauna and flora populations are generally resistant to localised fire events, animals can hide or hibernate/enter aestivation and the seeds of plants can survive the intense heat of forest fires.  Some plants even rely on seasonal fires to help them spread.  Based on these assumptions, it can be suggested that wildfires on their own are unlikely to be directly responsible for extinctions.  However, large dinosaurs which were unable to run very far, or shelter may have suffered terribly from such fires.

Dr Rory Hadden from the University of Edinburgh added:

“This is a truly exciting piece of inter-disciplinary research.  By working together engineers and geoscientists have tackled a complex, long-standing problem in a novel way.  This has allowed a step forward in the debate surrounding the end Cretaceous impact and will help geoscientists interpret the fossil record and evaluate potential future impacts.  In addition, the methods we developed in the laboratory for this research have driven new developments in our current understanding of how materials behave in fires particularly at the wildland-urban-interface, meaning that we have been able to answer questions relating to both ancient mass extinctions at the same time as developing understanding of the impact of wildfires in urban areas today.”

Everything Dinosaur would like to thank Exeter University for the use of a press release that enabled this article to be compiled.

Scotland’s Very Own Ichthyosaur

Dearcmhara shawcrossi - An Ichthyosaur from the Isle of Skye

No it’s not a dinosaur, contrary to some media reports.  It certainly is not “Nessie”, but it does mark the culmination of a tremendous effort by Scottish palaeontologists to collate and study marine reptile fossils that have been found in Scotland.  A new species of Ichthyosaur (marine reptile), has been described from fossils found on the Isle of Skye.  The “wee beastie” has been named Dearcmhara shawcrossi, the name comes from the Scottish Gaelic for marine lizard and the trivial name honours amateur fossil hunter Brian Shawcross who found the creature’s fossils at Bearreraig Bay in 1959.  Bearreraig Bay is part of a highly fossiliferous coastline which can be found on the eastern side of the island.  As far as we at Everything Dinosaur know, this is the first marine reptile to be given a Gaelic name, Dearcmhara is pronounced “jark vara”.

 A Model of an Ichthyosaur (Fish Lizard)

An Ichthyosaurus Model

An Ichthyosaurus Model

Picture Credit: Everything Dinosaur

 Around 170 million years ago, much of the Isle of Skye was underwater.  A shallow sea separated the landmasses of Europe and North America, this sea formed when rifts in the Earth’s crust led to the break-up of the super- continent Laurentia.  Marine reptiles like Dearcmhara shawcrossi were part of a diverse ecosystem, Dearcmhara grew to around 4.5 metres in length, motor boat size as described by Dr. Steve Brusatte (University of Edinburgh School of GeoSciences), who led the study.

Fossil Vertebra of the Newly Described Species

Most likely a dorsal vertebra from Dearcmhara.

Most likely a dorsal vertebra from Dearcmhara.

Picture Credit: BBC News

 Dr. Steve Brusatte (holding the fossil in the photograph) went onto comment:

“During the time of the dinosaurs, the waters of Scotland were prowled by big reptiles the size of motor boats.  Their fossils are very rare, and only now, for the first time we’ve found a new species that was uniquely Scottish.”

The Isle of Skye is a very important part of the world to palaeontologists.  Exposures along the shoreline and inland are strata that was laid down during the Middle Jurassic.  There are very few places in the world where such rocks are exposed and this makes any fossil discovery from the island very significant indeed.

Recently, Everything Dinosaur wrote about a new initiative to try and protect the island’s geological heritage in the wake of fears that unscrupulous fossil dealers might want to remove rare and valuable fossil bones of Plesiosaurs and Ichthyosaurs.

To read the article: Action Taken to Safeguard Scotland’s Fossils

The discovery of a new species of Scottish Ichthyosaur is just part of a collaborative effort being undertaken by researchers from the University of Edinburgh, the Hunterian Museum, the National Museums of Scotland, Staffin Museum (Isle of Skye) and Scottish National Heritage to try and catalogue significant vertebrate fossil finds.

A spokesperson from Everything Dinosaur commented:

“Without the donation made by local fossil enthusiast Brian Shawcross, this new species of Ichthyosaur would not have been recognised.  This goes to show how important amateur fossil collectors can be when it comes to learning about life in the past.”

To read an article that explains the importance of the Isle of Skye from a palaeontological perspective: Scotland’s Mid Jurassic Heritage

His and Her Trilobites

Dorset Fossil Expert Sends Everything Dinosaur Trilobites

For Brandon Lennon, fossil expert and Ammonite polisher supreme, this time of year is very busy as he prepares for the public Lyme Regis fossil walks which start again on Saturday 14th February.  February 2015, may seem a long way off, but for someone who spends his time studying the extensive fossil beds on this part of Dorset coast, it is merely a blink in geological time away.  Over the winter months, Brandon will be examining tide tables, looking at where rock falls and mud slides occur and plotting the best walks for those members of the public lucky enough to join him on his fossil finding adventures.

Brandon Lennon – Looking Forward to More Fossil Collecting in 2015

Exciting Plesiosaur Fossil Discovery

Exciting Plesiosaur Fossil Discovery

The picture above shows Brandon, with some beautifully preserved vertebrae from a Plesiosaurus, a marine reptile, fossils of which can be found eroding out of the cliffs on some parts of the Dorset coast.  Next year, marks the 200th anniversary of the publication of the world’s first extensive geological map.  The map that plotted the geology of England, Wales and parts of Scotland was created by the surveyor William Smith, (1769-1839), nick-named “strata Smith”, as it was Smith who used knowledge about which types of fossils could be found in which types of rock to plot the depositional sequence of strata.

This map, with its catchy title “A Delineation of the Strata of England and Wales with part of Scotland*, is regarded by many scientists and cartographers as one of the most important and significant maps ever created, it has even been dubbed “the map that changed the world”.  The geology of the Dorset coast is included, it forms one of fifteen sections that when combined produce the geological map.  Brandon and his father (a retired geologist), would be able to recognise the underlying geology as identified by Smith all those years ago.  Being able to identify the best places to look when it comes to finding fossils is a key skill for a leader of guided fossil walks and Brandon has more than twenty years experience in the role.

For further information on Guided Fossil Walks in the Lyme Regis area: Lyme Regis Fossil Walks

Brandon’s extensive interests are not confined to Jurassic aged sediments.  The other day, he kindly sent Everything Dinosaur a couple of Trilobite specimens to add to our Arthropod fossil collection.  Most vertebrate palaeontologists, when quizzed, will openly admit to having a passion for all things Trilobita.  These entirely marine relatives of crustaceans, insects and spiders, evolved during the Cambrian and survived right up to the End Permian mass extinction event.  Trilobites come in all shapes and sizes and the two specimens sent to us by Brandon are fine examples of the genus Calymene (the genus name means “beautiful crescent” and it is pronounced kal-im-minny).  These particular fossils probably come from Morocco and date from the Late Ordovician, making them approximately 270 million years older than the strata explored by Brandon and the groups he takes out on his fossil walks.

We have nick-named the Trilobites “Mike and Sue”.

Trilobite Fossils Sent to Everything Dinosaur by Brandon Lennon

"Mike and Sue" - the Trilobites.

“Mike and Sue” – the Trilobites.

Picture Credit: Everything Dinosaur

To read more about Brandon’s fossil hunting adventures including an article on Ammonite polishing: Fossil Experts Demonstrate Their Skills

*In Georgian times, in nascent scientific circles, there was a trend to give extremely long titles to publications.  It seems a case of don’t use one word when five words would do instead.  The full title of the 1815 geological survey map is:

“A  Delineation of the Strata of England and Wales with part of Scotland, exhibiting the collieries and mines, the marshes and fen lands originally overflowed by the sea, and the varieties of soil according to the variations in the substrata, illustrated by the most descriptive names by W. Smith.”

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