Category: Geology

3.7 Billion Year Old Microbial Structures?

A Rapid Emergence of Life on Earth?

When did life on Earth begin?  That is a very difficult question to answer, however, a team of scientists have published in the journal “Nature” this week suggesting that stromatolites (microbial colonies) existed in shallow marine environments as early as 3.7 billion years ago.  It’s all to do with waves and squiggles preserved in sedimentary strata from south-western Greenland.

Do These Wavy Lines and Structures Preserved in Ancient Sedimentary Rocks Indicate the Presence of Colonial Bacteria?

Are these wavy lines stromatolite fossils?

Evidence for ancient stromatolites?

Picture Credit: University of Wollongong

In the picture above the white scale bar represents 4 centimetres.

Although the paper is not without its controversy, if these waves and squiggles do turn out to be the ancient signatures left by mats of bacteria, then they would predate the previously oldest known fossils (from Australia) by some 200 million years or more.  Such claims are hotly contested, about as hot as the young Earth when the researchers (from a number of Australian institutions as well as from the UK), claim these stromatolites first existed.

The Isua Supercrustal Belt

The bleak, desolate uplands of south-western Greenland hold a secret.  The rocks here are the oldest surviving piece of the Earth’s surface.  As our planet continues to warm, so ice sheets shrink and slowly and surely, like the advance of geological time itself, new parts of our planet’s ancient crust are exposed.  This geological feature is called the Isua Supercrustal Belt (ISB).  Professor Martin van Kranendonk (University of New South Wales), specialises in the study of ancient life forms, dedicating his career to examining rocks for traces of Archean and Proterozoic life.  He and his colleagues hypothesise that the waves and cones seen in the ancient Greenland rocks are the traces of stromatolite stacks.

Researchers Exploring the ISB of Greenland

The Isua Supracrustal Belt of Greenland

The bleak and deserted part of south-western Greenland – on the hunt for ancient fossils.

Picture Credit: Picasa

Professor Kranendonk commented:

“We see the original unaltered sedimentary layers, and we can see how the stromatolite structures grow up through the sedimentary layering.  And we can see the characteristic dome and cone-shaped forms of modern stromatolites.”

If this is evidence of microbial colonies preserved in rocks some 3,700 million years old, then they predate by some 220 million years the previous most convincing and generally accepted evidence for the oldest life on Earth, the stromatolite fossils from the 3,480 million year old Dresser Formation of the Pilbara Craton, Australia.  These ancient rocks located in Western Australia are mostly volcanic in origin but the strata also preserves evidence of hydrothermal locations (hot springs), indicated by the presence of large quantities of the mineral barite.  These areas are associated with wrinkled structures, columns and cone shaped rocks, interpreted as evidence of stromatolite structures having existed within the hot springs and surrounding areas.

The ISB fossil material indicates the establishment of shallow marine carbonate production with biotic CO2 sequestration by 3,700 million years ago, close to the start of our planet’s sedimentary record.  If this is the case, then genetic molecular clock studies would push back the origin of life to before the Archaen Eon and into the Hadean Eon.  The Hadean Eon is the very oldest part of the Earth’s geological record.  It covers the period from our planet’s formation some 4.57 billion years ago to around 4 billion years ago (the start of the Archean Eon).  This suggests that life began on our planet when it was still being bombarded by extraterrestrial bodies, remnants from the formation of our solar system (the “Great Cometary Bombardment”).

Shark Bay Western Australia

Stromatolites can still be found today in various parts of the world (freshwater and marine environments).  For example, they can still be seen around the coast of Western Australia in a very saline body of water called Shark Bay.  The mushroom shaped structures found on the floor of the bay are the work of cyanobacterial communities.  Layers of mineral grains are glued together by the sticky, colonial bacteria.

Living Stromatolites (Shark Bay Western Australia)

Stromatolites at Shark Bay (Western Australia)

Stromatolite structures exposed at low tide (Shark Bay)

Picture Credit: sharkbay.org

To read an article from Everything Dinosaur published in 2010 about fossil evidence for the earliest animals found: Sponge-like Fossils May Be Earliest Animals

Scientists Search for Anthropocene “Spike”

Anthropocene Epoch Recommended by Geologists

The idea that we are now living in such a changed world as a result of the actions of our species, that a new geological epoch should be declared, is one step closer to reality.  A report from leading geologists presented at the 35th International Geological Congress held in Cape Town (South Africa), has recommended that the Anthropocene Epoch be added to the official geological history of Earth.  The decision to end the current epoch (the Holocene) and introduce a new geological time segment has not been finalised yet, more work needs to be done, specifically to decide at what point in time does the Holocene end and the new epoch, the Anthropocene (the age of humans), begin.

The Anthropocene Work Group (AWG)

A panel of experts has been put together to explore the possibility of creating a new epoch, the thirty-five members of the Anthropocene Work Group (AWG), presented their initial findings at the International Geological Congress and now work has started to identify the best point in time for the Holocene to end and the Anthropocene to start.  Twenty-eight of the panellists believe that the Anthropocene should be recorded as having started sometime in the 1950’s, the decade identified as being the start of intense human activity that increased the impact of our species.

Identifying a Suitable Marker in Time

The search is on to find a “golden spike”, to identify a suitable marker in the environment that epitomises the start of a new phase in our planet’s history.  Some of the panel members have argued that July 16th 1945 could be that marker.   On that day, the first test of a nuclear bomb took place in New Mexico (code name Trinity).  Plutonium fallout from nuclear bombs will be present in sediments laid down at the time and over thousands of years the sediments will eventually form strata and the layers with unnaturally high levels of plutonium could provide the long-term geological evidence to indicate the start of a new and distinct unit of deep time.  However, other geologists think that rocks that contain large amounts of plastic compounds would make a better starting point for the Anthropocene.

Scientists Aim to Pinpoint in Strata the Starting Point for the Anthropocene Epoch

Llanwit Major Jurassic Cliffs

Preserving our planet’s geological history.

Picture Credit: UK Fossils Network

Colin Waters (British Geological Survey), the secretary of the AWG, presented the team’s initial findings at the Congress he explained:

“This is an update on where we are in our discussions, we’ve got to a point where we’ve listed what we think the Anthropocene means to us as a working group.  The majority of us think that it is real, that there is something happening, that there are clearly signals in the environment that are recognisable and make the Anthropocene a distinct unit and the majority of us think it would be justified to formally recognise it.”

Atomic Testing and the Radioactive Particles Produced Could Provide a Marker in Deep Time

An atomic bomb and its mushroom cloud.

Scientists propose that atom bomb tests in the 1950’s could represent the start of a new geological epoch.

A Changing World

Our planet has gone through huge changes since the time of its formation some 4.58 billion years ago.  Geologists have broken down this immense period of time into units, with each component of the official timeline of our planet marked by distinct boundaries, preserved in the rocks.  This timeline of our Earth’s history is referred to as the Chronostratigraphic Chart and any changes made to it need to be agreed by the International Commission on Stratigraphy (ICS) and then be further ratified by the executive committee of the International Union of Geological Sciences (IUGS).  The Anthropocene Working Group hope to present their findings within two years so that by 2019, a new geological epoch could be established.

The last time there was a major revision of the Chronostratigraphic Chart was in 2009, when, in a controversial move, scientists agreed to revise the date of the Quaternary Period: The Quaternary Just Gained 800,000 years.

Although there is still debate as to the impact of our species on climate, most scientists and academics agree that we are entering a new phase of climate change.  Our world is getting warmer, the implications for a rapid and dramatic rise in global temperatures are frightening, hence the limits on temperature increases agreed at the recent Paris Conference (2015).  Creating a new geological epoch may seem like an exercise in semantics for some, but in reality, it would be an affirmation that our species H. sapiens is having such a profound effect on the planet that dramatic changes with far reaching consequences are now beginning to occur.  A new marker in the Chronostratigraphic Chart might help to drive change, providing a definitive rallying point for mankind to act collectively to put in place measures to help limit the impact we are having on the planet.

A related article on the global context of climate change: COP 21 – The Impact of Global Climate Change

Our Species Is Having a Dramatic Impact on the Planet

Plastic pollution, the impact of mankind on the environment

Non-biodegradable plastics and other debris on a beach.

A study that shows climate change between the Pliocene and Pleistocene may help our understanding of current climate change issues: Pliocene/Pleistocene Climate Studies Supports Current Climate Change Models.

The Impact of Ice Age Mammals (mega-fauna) on the start of the Holocene: Calls for the Start of the Holocene Epoch to be Altered.

Dr. Waters explained that in the past, climate change had taken place due to natural oscillations within our Earth’s ecosystems and environments, however: “in the last Century we have had such a huge impact that we’re actually taking the planet away from that natural oscillation and changing the trend for global temperatures from what should have been a cooling trend to a warming trend.”

Thirsty Woolly Mammoths of St. Paul Island

St. Paul’s and Wrangel Island Woolly Mammoth Populations

This week has seen the publication of research undertaken by an international team of scientists led by academics from the University of Pennsylvania, that explains the demise of one of the last populations of Woolly Mammoths to have lived on Earth.  Mammoths (Mammuthus primigenius) survived on the remote Alaskan island of St. Paul until around 5,600 years ago (+/- 100 years or so), whilst their mainland cousins were extinct by about 10,500 years ago.  Writing in the “Proceedings of the National Academy of Sciences” (United States), the researchers conclude that a warming climate which led to rising sea levels caused the amount of freshwater available to fall dramatically, in essence the Woolly Mammoths died of thirst.

Study Suggests Some of the Last of the Woolly Mammoths were Unable to Quench Their Thirst

Mammoths died of thirst on St. Paul Island.

Lack of freshwater is suspected to have led to the demise of the Woolly Mammoth population on St. Paul Island.

Picture Credit: Everything Dinosaur

The Island of St. Paul in Relation to Wrangel Island

Readers of this blog will probably know that the very last population of Woolly Mammoths to have existed, survived on Wrangel Island until about 4,300 years ago (although an extinction date of as recently as about 1,700 B.C. has been proposed).  Both St. Paul Island and Wrangel are remote locations deep within the Arctic circle, however, there are considerable differences between these two islands and whilst scientists such as Professor Russell Graham (University of Pennsylvania) and lead author of the St. Paul Island study, propose that a lack of drinking water led to the St. Paul’s Island Mammoth population dying out, debate remains as to the probable cause of the Wrangel Island extinction.  In both cases the presence of humans impacting on the population of Mammoths can be ruled out, these hairy elephants were long gone before the first humans visited these isolated, desolate places (once sea levels rose).

The Location of St. Paul Island in Relation to Wrangel Island

The location of the last of the Woolly Mammoths (St. Paul Island and Wrangel Island).

The dark grey areas represent today’s landmass, the light grey areas show the extent of the Bering Land Bridge (Beringia).

Picture Credit: PNAS with additional annotation by Everything Dinosaur

The picture above shows the approximate position of the Bering Land Bridge (Beringia) in light grey compared to the landmasses of Siberia and Alaska today (dark grey).  At its maximum during the Quaternary glacial intervals, the land joining Asia to North America would have been over six hundred miles wide, over the last 20,000 years rising sea levels led to the eventual loss of a land link between the continents of North America and Asia.

St. Paul Island was part of the southern portion of Beringia. Today, it is located in the Bering Sea.  In contrast, the much larger Wrangel Island is found in what was the northern portion of Beringia and it is located today in the Arctic Ocean.  Wrangel Island is over seventy times bigger than St. Paul Island, in the past both these islands were considerably bigger but with a warming climate in the latter stages of the Pleistocene and into the Holocene Epoch, sea levels rose and St. Paul Island in particular began to shrink.  The island is presently, around forty square miles in size, the researchers used a variety of techniques to plot the ingress of sea water and the decline of freshwater on the island over the last fifteen thousand years.

The Reduction of St. Paul Island from the Late Pleistocene to the Present Day

St. Paul Island 15,000 years ago to the present day.

The shrinking of St. Paul Island over the last fifteen thousand years.

Picture Credit: PNAS

The picture above shows a palaeogeographical map compiled by the research team that plots the reduction in the size of St. Paul Island over the last 15,000 years or so.  The red dot in the centre of the island (present size is outlined in brown), represents Lake Hill, a small, freshwater lake from which a series of sediment cores were extracted so that the scientists could trace the history of the location and how changes in climate affected the fauna and flora of the island.

The sediment cores (taken in 2013), built on data generated from core samples taken back in the 1960’s and they have provided a number of independent indicators to suggest that the Mammoth population survived until around 5,600 years ago.  The flora of St. Paul Island remained relatively unchanged, however, the scientists were able to deduce that St. Paul Island shrank rapidly due to rising sea levels until about 9,000 years ago.  It continued to shrink, albeit more slowly until around 6,000 years ago but declining freshwater sources and a generally drier climate with reduced precipitation from around 7,850 years ago to the time of the Mammoth’s extinction was probably the cause of the demise of this elephant population.

Independent Indicators of Mammoth Extinction

  • Analysis of sedimentary ancient DNA (sedaDNA) to provide an understanding of the ancient flora of the environment and how a drying climate and rising sea levels impacted upon it.
  • The level of fungal spores that are associated with animal dung (coprophilous fungal spore types).  Three types of fungal spore were studied, this fungi would have thrived on Mammoth dung, the sudden elimination of the fungal spores from the core samples indicate a mega fauna extinction.
  • Micro fossils such as those of water fleas (indicating freshwater) and pollen grains along with diatoms (different types of algae some of which are associated with sea water).
  • Magnetic susceptibility, in arbitrary units (AU) of Lake Hill sediments from the cores, this data looks at the differences between different types of sediment and from this an understanding of changes in the palaeoenvironment over time can be mapped.
  • Radiocarbon dating, isotope degradation analysis and analysis of protein remnants from St. Paul Island Mammoth remains.

Given the variety of information sources, the “best fit” for the Mammoth extinction is approximately 5,600 years ago (+/- 100 years).

The Mammoths Contributed to Their Own Downfall

As sources of freshwater dwindled, so the Mammoths would have congregated around the remaining waterholes.  More intensive, localised Woolly Mammoth activity would have accelerated the fall in water levels.  Vegetation would have been consumed therefore exposing sediments that would have been washed into the lakes and ponds thus degrading the water quality, reducing water levels further and exacerbating the already acute water shortage.

A spokesperson from Everything Dinosaur commented:

“Extant Indian elephants can consume as much as two hundred litres a day, sometimes more if it is a lactating female.  We suspect Mammoths too, had a high demand for drinking water.  A concentration of mega fauna around remaining sources of drinking water on St. Paul Island would have probably accelerated the extinction.  It is also likely, that with large animals having to survive on an ever diminishing landmass, the elephant population was already probably under considerable environmental stress.”

Lead author of the PNAS paper, Professor Russell Graham explained a likely extinction scenario:

“They [the Mammoths] were milling around, which would destroy the vegetation, we see this with modern elephants.  This allows for the erosion of sediments to go into the lake, which is creating less and less fresh water.  The Mammoths were contributing to their own demise.”

The scientific paper: “Timing and causes of mid-Holocene Mammoth extinction on St. Paul Island, Alaska”.

Concerns for the Coastal Norfolk Fossil Sites

Experts Fear for Fossils and Safety of Fossil Hunters

Scientists at the Norfolk Museums Service along with British palaeontologists and geology societies have expressed concern over the rise in unscrupulous fossil hunting activities being reported from parts of the Norfolk coast.  These famous Pleistocene age deposits have yielded an extensive array of vertebrate fossils including many large mammals such as rhino and elephant.  One of England’s most important fossil finds, the spectacular West Runton elephant (more correctly termed a Steppe Mammoth – Mammuthus trogontherii), was found in the cliffs.  The discovery, the first bones were found in 1990, represents the largest and oldest nearly complete fossil mammoth from the UK.  Bones and teeth can still be found on the foreshore but sadly, there has been a rise in reports of fossil hunters digging into the cliffs in a bid to find more specimens.

A spokesperson for the Norfolk Museums Service advised against such excavation, not only would the digging potentially damage any fossil material but as the cliffs were unstable, working so close to the cliffs was very dangerous.  He expressed grave concern following reports of a rise in the number of fossil hunters “hacking into the cliff tops”

The Foreshore and Cliffs at West Runton (North Norfolk)

A view of the famous West Runton beach, a great place to find fossils.

A view of the famous West Runton beach, a great place to find fossils.

Picture Credit: ukfossils.co.uk

The freshwater Pleistocene deposits and associated Cretaceous chalks yield a large number of different types of fossil.  As well as freshwater molluscs and mammal remains from the freshwater beds, the chalk is highly fossiliferous and different types sea urchin and fossil sponges can be found.  The picture above shows a view of West Runton beach and the dangerous cliffs, the pier at Cromer can be seen in the background.

A team member from Everything Dinosaur commented:

“This part of the Norfolk coast is subject to high levels of erosion, we would urge all fossil collectors to stay on the beach and look for fossils at low tide along the foreshore, the rapidly eroding cliffs are delivering lots of fossil material onto the beach area and this is a wonderful location for a family fossil hunt.  However, please don’t dig into the cliffs and we urge all visitors to follow the fossil collecting code.”

For an article on the fossil collecting code and a guide to safe collecting: Everything Dinosaur’s Guide to Fossil Collecting Safely

Register Fossil Finds with the Norfolk Museums Service

A partial Mammoth tooth was found nearby last month and no doubt other finds will be reported over the summer at this popular tourist attraction.  Palaeontologist Dr. Waterhouse of the Norfolk Museums Service and the leader of the Cromer Forest-bed Fossil Project reminded fossil hunters that it was good practice to report finds to the Norfolk Museum Service, the museum at Cromer just a few miles from West Runton, was a good place to take any fossil finds and team members from the Norfolk Museums Service would be happy to assist with identification.  As Mammoth fossils, especially tusks and teeth are very popular with collectors, it is likely that many of the overzealous fossil hunting activities have been driven by the high prices such fossils make on auction sites.

A Model of a Woolly Mammoth (M. primigenius)

A model of a Woolly Mammoth.

A model of a Woolly Mammoth.

Picture Credit: Everything Dinosaur

Dr. Waterhouse said:

“Norfolk is the best place in the country and probably Europe to find Mammoth remains because they went through about six sets of teeth in their lifetime, so there is a lot more teeth than there were Mammoths.  Something that I think needs highlighting is poor and even dangerous fossil collecting by people hacking into the cliffs at places like West Runton.  Ethical collecting is high on my agenda, and also recording fossil finds as part of the Cromer Forest-bed Fossil Project, so that important scientific information isn’t lost forever.”

At Everything Dinosaur we echo the views of Dr. Waterhouse and we urge fossil hunters to take care and to abide by the fossil collecting code as well as local bye laws and regulations.

Antarctic Expedition Provides Window into Late Cretaceous Seacape

Fossilised Birds, Ammonites and Giant Marine Reptiles

A team of international scientists including researchers from the University of Queensland and the Carnegie Museum of Natural History, have been showing off their vast collection of fossils after a very successful expedition to Antarctica earlier this year.  The fossils, estimated to weigh over 1,000 lbs, provide evidence of life in a shallow sea close to land some 71 million-years-ago (Late Cretaceous).  The specimens were collected from James Ross Island, a forty mile long island on the south-eastern side of the Antarctic peninsula, a long finger of land that points towards South America, although the island itself is more than six hundred miles from the Chilean mainland.

Some of the Fossils Found During the Two-Month Long Antarctic Expedition

Spectacular fossils preserved in nodules found in Antarctica.

Spectacular fossils preserved in nodules found in Antarctica.

Picture Credit: University of Queensland

The picture above shows a number of split nodules that contain invertebrate fossils of various kinds including a number of Ammonite specimens.  The geological hammer, probably the one used to split the nodules provides scale.  Over two hundred different fossils have been collected by the scientists.

Marine Reptiles and Dinosaurs

One of the main objectives of the research team over the two month period of the expedition (February to March) was to search for vertebrate fossils to provide information on the marine and terrestrial fauna that existed in this part of Gondwana towards the end of the Cretaceous.  Giant shark vertebrae the size of saucers, as well as Plesiosaur and Mosasaur remains along with bird fossils were discovered, these fossils along with the other specimens are currently being stored in Chile prior to onward transport to the Carnegie Museum of Natural History (Pittsburgh, Pennsylvania) for preparation and study.  It is likely that a number of new species will be identified.

Palaeontologists Working on a Plesiosaur Shoulder Girdle

Palaeontologists carefully excavate the shoulder girdle of a Plesiosaur (James Ross Island).

Palaeontologists carefully excavate the shoulder girdle of a Plesiosaur (James Ross Island).

Picture Credit: Dr.  Matthew Lamanna (Carnegie Museum of Natural History)

The picture above shows graduate student Abby West (American Museum of Natural History) working alongside Dr. Steve Salisbury (University of Queensland) and marine technician Julia Carlton as they carefully prepare the shoulder girdle of a Plesiosaur for extraction by helicopter.  The location of the fossil sites are so inaccessible that they only way such large specimens could be removed was by helicopter.  The choppers used to support the field team were called “raptors” – very Jurassic Park as one expedition member quipped.

The photograph was taken by Dr. Lamanna (Assistant Curator of Vertebrate Palaeontology), an expert on the terrestrial fauna of Gondwana, a few days ago, Everything Dinosaur reported on the naming of a new giant Titanosaur from Argentina that had been named based on the extensive study of a beautifully preserved skull and neck elements that had been found some years before (Sarmientosaurus musacchioi).

To read more about this story: Late Cretaceous Titanosaur from Patagonia

Identifying New Fossil Sites

The scientists are part of an international Antarctic research project – Antarctic Peninsula Paleontology Project (forgive the Americanised spelling), or AP3 for short.  Consisting of specialists in vertebrate palaeontology and geology, the team heralds from universities and museums from the United States, Australia, South Africa, Chile and the UK.  Located a gruelling six mile hike from the team’s base camp the main fossil bearing beds are located on the steeply sloping south-western flank at Sandwich Bluff on Vega Island, which is located just a few thousand metres to the north-west of James Ross Island.  Much of the strata exposed around James Ross Island dates from the very Late Cretaceous and from the very Early Palaeogene.  A number of new fossil bearing sites have already been located including several plant remains beds and two previously undocumented Cretaceous exposures that were targeted for future field work.

The Late Antarctic Summer – Hiking Looking for Fossils

Isolated and very difficult to reach - fossil hunting in Antarctica.

Isolated and very difficult to reach – fossil hunting in Antarctica.

Picture Credit: The Carnegie Museum of Natural History

The Antarctic A Potential Treasure Trove of Fossils

The James Ross Island basin is one of the few parts of Antarctica where the snow and ice melts sufficiently to expose the rock strata below.  The absence of soil helps with the exploration, although we tip our hard hats to the research team members who braved freezing temperatures, howling gales and sea sickness just to reach the fossil quarries.  The specimens were excavated from the Upper Cretaceous Sandwich Bluff Member of the López de Bertodano Formation.  The beds here represent deposits in a shallow, marine environment with occasional occurrences of terrestrial material (particularly plant remains) that would have been washed into the sea from the nearby land.  Dinosaur fossils were found, although fragmentary, the palaeontologists are confident that these fossils will help to extend our understanding of the Late Cretaceous dinosaur fauna of Antarctica.

Commenting on the research, Dr. Salisbury explained:

“It’s a very hard place to work, but it’s an even harder place to get to.  A lot of the bigger bones will need quite a bit of preparation before we can do much research on them.  Working in Antarctica is tough!”

Fossilised remains of birds were also found, including early ducks dating from the end of the Cretaceous period.

It’s a Tough Job – Searching for Fossils in the James Ross Island Basin

Lying down on the job!  Looking for fossils in the Antarctic.

Lying down on the job! Looking for fossils in the Antarctic.

Picture Credit: Carnegie Museum of Natural History

A spokesperson from Everything Dinosaur paid tribute to the research team and their supporters stating:

“The Antarctic provides vertebrate palaeontologists the opportunity to explore pristine fossil bearing environments without the risk of damage from vandals or illegal fossil hunters.  This treasure trove of fossils, currently in Chile, will provide scientists with a great deal of data regarding the fauna and flora at what was a pivotal moment in the history of life on Earth.”

In the summer of 2015, Everything Dinosaur reported on the discovery of a Plesiosaur, but this time from the other end of the world – the Arctic.

To read an article about this amazing fossil find: Elasmosaur Fossil from Alaska

Lyme Regis Fossil Festival in Full Swing

Lyme Regis Fossil Festival 2016

The 2016 Lyme Regis Fossil Festival is in full swing.  After a successful day yesterday with around two dozen primary schools attending, Friday is dedicated to supporting secondary schools, those pupils at Key Stages 3 and 4 of the English national curriculum.  Local fossil expert Brandon Lennon reports that there were some strong winds battering the Dorset coast earlier in the week, this affected the build up to the Festival but all the marquees were erected and everything made ready for what will be four days for frenetic fossil themed activities.

The View Towards the Famous Lyme Regis Cobb

Lyme Regis prepares for the 2016 Fossil Festival.

Lyme Regis prepares for the 2016 Fossil Festival.

Picture Credit: Brandon Lennon

Even in bad weather, Lyme Regis is picturesque.  This part of the “Jurassic Coast” tends to have its own micro-climate, a phenomenon that team members at Everything Dinosaur have experienced themselves.  It can be raining in Sidmouth (Devon) to the west, but the Lyme Regis and Charmouth areas stay dry.  The weather forecast for the weekend, the public open days of the 2016 festival, is much better.  Strong sea breezes are still in the forecast but it is going to be dry and as a result, even more visitors are expected.  It is going to be a busy couple of days for the organisers and the exhibitors.

The Marquees Along the Sea Front

All is ready for the Lyme Regis Fossil Festival 2016.

All is ready for the Lyme Regis Fossil Festival 2016.

Picture Credit: Brandon Lennon

To visit the Lyme Regis Fossil Festival website: Lyme Regis Fossil Festival 2016

The theme of this year’s festival is “promoting science to young people” and there will be lots to do and see at Lyme Regis over the next couple of days or so.  However, team members at Everything Dinosaur have received reports about further minor rock falls from the cliffs surrounding the town.  A spokesperson from Everything Dinosaur commented:

“The cliffs remain saturated and further rock falls over the next few days cannot be discounted.  We urge visitors to the Festival to take care whilst on the beach and to stay away from the bottom of the cliffs.”

One of the best ways to enjoy the geology of Lyme Regis and Charmouth is to take part in a guided fossil walk.  There are a number of these walks built into the programme of the Festival itself, but other walks are available throughout most of the year.

To learn more about organised fossil walks in the Lyme Regis area: Lyme Regis Fossil Walks

Amazing Fossils to Find and Lots to See (and Buy)

For those who would prefer not to explore the beaches themselves, there will be lots of fascinating fossils on display in the marquees.  Many of the specimens on display have been found in the Dorset area and can be purchased, there will certainly be many different Ammonites to choose from, if Chris Moore’s trade stand is anything to go by.

Chris Moore (Forge Fossils, Charmouth) Prepares his Trade Stand

A splendid display of Lyme Regis fossils.

A splendid display of Lyme Regis fossils.

Picture Credit: Everything Dinosaur

It looks like there will be one or two bargains to be had.  There will also be plenty of opportunities to discuss the ancient fauna of Lyme Regis with the multitude of local fossil experts who will be attending this year’s event, in addition, visitors have the chance to meet scientists from the Natural History Museum, British Antarctic Survey, Palaeontological Association, Plymouth University, Natural England, Jurassic Coast Trust, Dorset Geologists, Geological Society, Lyme Regis Museum, Charmouth Heritage Coast Centre, National Trust, Dorset Wildlife Trust and the National Oceanography Centre.

We wish the Festival every success and we look forward to hearing more about the 2016 Lyme Regis Fossil Festival over the weekend.

New Model to Help Find Fossils

Serendipity Taken Out of Fossil Finding

Very often a major fossil find is attributed to serendipity, someone being in the right place at the right time.  Even the most experienced palaeontologist needs a little bit of luck, take for example the discovery of the ancient hominin Homo floresiensis on the Indonesian island of Flores.  Had the research team excavated an area just one metre either side of that part of the cave they did excavate they would never have found the beautifully preserved skull and partial skeleton of an individual (the holotype LB-1).  Yes, “lady luck” does play a part in many new scientific discoveries.  However, an international team of scientists, including researchers from the University of Adelaide, have created a mathematical model to help fossil hunters find the remains of long-extinct animals.

Combining Scientific Disciplines to Predict Where Fossils Can Be Found

The international team, that included researchers from Kiel University (Germany), as well as Australia, looked at the estimated ages of the fossils from a number of extinct Australian megafauna and plotted known fossil find locations for these creatures against data for the prehistoric climate of Australia.  This provided a guide to the maximum likely ranges of the animals in the study.  This information was then mapped against the geology of Australia to provide an indication of what suitably aged, likely fossil bearing strata was exposed.  Weighting for the erosion potential of the rocks was built into the mathematical model and this data set could then be used to help determine the best areas in the country to look for the animal’s fossil remains.

A paper detailing the research has been published in the on line journal PLOS One, the research team confidently state that their model can provide fossil hunters with guidelines on how to find fossils elsewhere in the world too.

Determining the Best Places to Hunt for Fossils

Combining palaeoclimate data with erosion studies and known fossil finds to predict where fossils can be found.

Combining palaeo-climate data with erosion studies and known fossil finds to predict where fossils can be found.

Picture Credit: Sebastián Block, Frédérik Saltré,  Marta Rodríguez-Rey, Damien A. Fordham, Ingmar Unkel, Corey J. A. Bradshaw

The picture above provides an illustration of how the mathematical model was constructed and how to implement it.  For any given type of extinct animal (in this example, the giant marsupial Diprotodon), the red map at the bottom shows the likely places to hunt for fossils of that animal.  The darker the red shading the more likely that location is to be a “fossil finding hot spot”.   The red map has been created by looking at certain variables, namely:

  • Where the animal used to live – a map created by assessing ancient climate data and known fossil finds (the brown map).
  • Where the fossils could be preserved – using an assessment of the geology of the local area (blue map).
  • Where it is now possible to find the fossils of that particular animal, building in an assessment of erosion profiles of the likely fossil bearing strata (green map).

The scientists are confident that this systematic approach to fossil finding is more likely to be successful than random approaches to fossil hunts, even out-doing sophisticated approaches such as using satellite data to identify likely fossil bearing outcrops and exposures.

Five genera of Late Pleistocene megafauna were selected for this study.  All had an extensive and relatively widely distributed fossil record on the continent and since all had become extinct relatively recently there was plenty of evidence to support an assessment of the ancient climate.  The creatures studied were Thylacoleo (the marsupial lion), Protemnodon (a giant wallaby), the cow-sized, giant marsupial  Zygomaturus, the flightless bird Genyornis and Diprotodon, the largest marsupial known to science.

Diprotodon Played a Role in the Study

Diprotodonts - Giant Marsupials

Diprotodon – A Giant Marsupial.

Picture Credit: Australian Museum/James King

Although all these five genera are unique to Australia, the scientists had sufficient fossils to create an accurate map of the creatures prehistoric distribution.

Commenting on the reasoning behind their model, project leader, Professor Corey Bradshaw, (Sir Hubert Wilkins Chair of Climate Change at the University of Adelaide) stated:

“A chain of ideal conditions must occur for fossils to form, which means they are extremely rare, so finding as many as possible can tell us more of what the past was like, and why certain species went extinct.  Typically, however, we use haphazard ways to find fossils.  Mostly people just go to excavation sites and surrounding areas where fossils have been found before.  We hope our models will make it easier for palaeontologists and archaeologists to identify new fossil sites that could yield vast treasures of prehistoric information.”

Lead author of the scientific paper Sebastián Block explained that the team made use of modelling techniques already used widely in ecology.  They looked at the past distribution of these prehistoric genera, where fossils were likely to have formed and the probability of making field discoveries.  The model may not make the back-breaking work of excavating fossils any easier, but at least palaeontologists will be looking in the most likely places.

The Probability of Finding Fossils

Combining disciplines increases the probability of finding fossils.

Combining disciplines increases the probability of finding fossils.

Graph Credit: Sebastián Block, Frédérik Saltré,  Marta Rodríguez-Rey, Damien A. Fordham, Ingmar Unkel, Corey J. A. Bradshaw

The bar chart above shows how the model increases the likelihood of fossil discovery for the five genera studied.  The chances of finding a fossil of that particular genus compared to a random search is plotted on the vertical (Y axis).  The blue bars represent the probability of finding a fossil based on an assessment of ancient climate.  The green bars show the probability of a successful fossil hunt using just geological data and erosion assessments.  The red bars show the increased likelihood of success after the application of the variables used in this assessment (ancient climate, preservation potential and known discoveries).  The dashed line outlines the probability of finding a fossil using a random search in a known fossil bearing locality.

Likely Fossil Preservation Sites Accounted For

The team added into their data relevant predictors for the likelihood of fossil discoveries.  For example, many Late Pleistocene fossils are found in caves so the number of caves in the areas studied were also plotted.  In addition, as Australian megafauna (indeed most terrestrial animal fossils), are found in association with ancient lakes and rivers, areas where sedimentary material can be built up were given greater weighting as indeed were areas that tended to be more open and devoid of extensive plant cover as this would make fossil finding easier.

Using the model, likely fossil “hot spots” identified include the area south of Lake Eyre (South Australia), the land to the west of Lake Torrens (also South Australia) and the Shark Bay locality in Western Australia.

Kiel University’s Professor Ingmar Unkel added:

“Our methods predict potential fossil locations across an entire continent, which is useful to identify potential fossil areas far from already known sites.  It’s a good “exploration filter”; after which remote-sensing approaches and fine-scale expert knowledge could compliment the search.”

Luck will still play a role in fossil discoveries but at least this mathematical model helps to swing the odds in the scientists favour.

Small Abelisaurid from Argentina

Not all of Argentina’s Dinosaurs were Giants

Last month Everything Dinosaur published details of a new super-sized Titanosaur from Argentina.  An enormous animal that was to be featured in a special BBC television documentary “Attenborough and the Giant Dinosaur”.  However, not all of Argentina’s dinosaurs were huge, scientists writing in the journal “Science Direct” have reported the discovery of fossil meat-eating dinosaur bones that may represent one of the smallest abelisaurids known from South America.

To read about the new giant dinosaur: “Sir David Attenborough and the Giant Dinosaur”

Not All South American Abelisauridae were the Size of Carnotaurus

"Meat-eating Bull" from Papo.

“Meat-eating Bull” from Papo.

Picture Credit: Everything Dinosaur

Researchers from a number of Argentinian institutions operating under the collective umbrella of CONICET – The National Scientific and Technical Research Council, the country’s main academic body responsible for the promotion of science and technology, have reported finding the partial and fragmentary remains of a new abelisaurid dinosaur from north-west Patagonia.

The Rich Fossil Assemblage of the Candeleros Formation

Field work exploring the sandstone strata of the Candeleros Formation (Neuquén Province), has uncovered a partial femur, ribs, toe bones, a fragmentary pelvis, two fused sacral centra (from the vertebrae fused to the hip region) and a small piece of skull bone, identified as a frontal.  Although a histological analysis reveals that the animal was fully mature when it died, perhaps around fourteen years old, it is estimated to have been a little over four metres long and to have weighed about 240 kilogrammes.  That’s about half the length of Carnotaurus and around one quarter of the body weight.   This dinosaur is one of the smallest abelisaurids known and a study of the bone fibres indicates that this dinosaur had a relatively lower growth rate when compared to other abelisaurids such as the much larger Aucasaurus garridoi, whose fossils also come from Argentina but from younger deposits.  Aucasaurus roamed Argentina around 85 million years ago, whereas this as yet, unnamed member of the Abelisauridae lived some eight million years earlier.

This new type of meat-eating dinosaur extends the Theropod fauna of the Candeleros Formation.  As well as a number of abelisaurids, the Candeleros Formation is associated with carcharodontosaurids, a dromaeosaurid and alvarezsaurids.

Quarry Site Might Reveal Evidence of Cretaceous Mass Extinction

Potential to Map End Cretaceous Extinction Event in New Jersey Quarry

The eastern part of the United States might be regarded as something of a “poor relation” to the western side of the country when it comes to dinosaur bones.  True, eastern USA dinosaur fossils are much rarer than from locations such as Wyoming, Utah, Arizona, Colorado and Montana in the west, but the State of New Jersey might just have one very special “Lagerstätte”, that tops those vertebrate fossil bearing rocks known elsewhere in America.  A disused quarry located close to the township of Mantua might provide palaeontologists with unique insights into the End Cretaceous mass extinction event that wiped out the non-avian dinosaurs.

New Jersey Quarry Might Provide Fresh Insight into Cretaceous Mass Extinction Event

Excavating invertebrate fossils in the quarry.

Excavating invertebrate fossils in the quarry.

Picture Credit: Rowan University

Around sixty-five million years ago, this site was at the bottom of a shallow sea, close to the landmass known as Appalachia.  In one layer of rock, about fourteen metres below the level of today’s land surface, scientists have found a treasure trove of marine fossils.  Professor Kenneth J. Lacovara, a professor of palaeontology and geology at the nearby Rowan University describes this particular bed as a “mass death assemblage”.  Could all these animals have perished as a result of a single catastrophic event, such as an extraterrestrial impact event?

If this is the case, then this quarry, which sits behind a shopping mall, could be the only site in the world where animal remains can be found that date from the End Cretaceous mass extinction event.  Fossils are found in a number of rock layers in the quarry, but a vast assemblage is confined and concentrated to one bed in the strata.  The rocks have been dated to around 65 million to 66 million years old, but further radiometric and biostratigraphic analysis is required before the link with the mass extinction event can be given more validity.  If a connection is established, then this location could provide an unparalleled window into a pivotal moment in the history of life on Earth.

Elevated amounts of the rare Earth element iridium found in close proximity to the richest fossil bearing layer, indicate that these animals lived at a time extremely close to what is believed to have been an asteroid impact, one that played a major role in the extinction of about 75% of all terrestrial species.

Last year, Rowan University entered into an agreement to purchase the sixty-five acre site.  The University intends to turn the quarry into a world-class educational resource.  A number of open days have already been organised and it has been estimated that some 8,000 local people have already taken part in fossil digs.

An Aerial View of the Mantua Quarry Site

A window into the End Cretaceous extinction event.

A window into the End Cretaceous extinction event.

Picture Credit: Rowan University

Fossils found include a vast array of marine invertebrates, animals like Brachiopods, Bivalves and Molluscs.  In addition, shark teeth are relatively common and fossils from ancient crocodiles and turtles have also been discovered.  Occasionally, the fossilised remains of a Mosasaur (marine reptile) are found.  Bones and other remains from once living organisms such as teeth and shells can pile up as underwater currents relocate them on the seabed, concentrating them into one area, perhaps where the current dies away.  However, at this location, one bed reveals skeletons of larger animals have remained relatively intact.  This suggests that these animals all died at approximately the same time and then settled gently on the sea bottom.  Initial dating assessments, puts this fossil layer tantalisingly close to the extraterrestrial impact event that took place in the Yucatan peninsula (Mexico).

Now that the future of this rather special site has been secured, scientists hope to undertake a much more extensive study of the palaeogeography of the area and to establish this location’s potentially unique relationship to the extinction event that wiped out the non-avian dinosaurs as well as the Pterosauria and most of the marine reptiles.

The Dinosauria Sprinted Out of the Blocks

New Study Suggests the Dinosaurs Evolved Quickly

An international team of researchers have accurately dated rock layers exposed in north-western Argentina deposited during the Triassic.  The subsequent geological timeline they have been able to construct suggests that the time elapsed between the emergence of early dinosaur relatives and the origin of the first dinosaurs is much shorter than previously believed.  In essence, the Dinosauria evolved much more quickly than previously thought.

North-western Argentina Around 235 Million Years Ago

Diverse fauna of north-western Argentina

Diverse fauna of north-western Argentina including ancestral dinosaurs.

Picture Credit: Victor-Leshyk

The Triassic A Time of Transition

The vertebrate fauna of the Triassic (approximately 251 million to 201 million years ago), changed dramatically.  Few of the fossil lineages found in Lower Triassic rock formations can be found in strata laid down later on.  The mass extinction event that marked the end of the Palaeozoic and the beginning of the Mesozoic led to a radical shift in the diversity, type and geographical distribution of back-boned land animals and arguably, the emergence of more modern-looking ecosystems.  To help unravel some of the mysteries surrounding this “faunal shift” and to more accurately date the appearance of the first dinosaurs, the scientists travelled to north-western Argentina (La Rioja Province) and set about dating different beds that make up the exposed sandstones and mudstones of the Chañares Formation.

The debate as to where and exactly when the first dinosaurs evolved is one of those topics that comes up frequently at symposiums and conventions.  The evidence suggests that the Dinosauria first appeared in the southern hemisphere and for a long time South America was thought to have been the place they originated from.  Research published in 2013 challenged this idea, proposing that Africa may have been home to the first dinosaurs, but exactly when did the dinosaurs as an Order of reptiles (Dinosauria) really take off?  At what point in geological time did the dinosaurs commence their journey to becoming the dominate terrestrial life forms of the Mesozoic?

To read an article regarding the possibility of dinosaurs having first evolved in Africa: Africa – The Cradle of the Dinosauria?

Problems Accurately Dating Deep Time

The sedimentary exposures of the Chañares Formation permit accurate stratigraphic dating because of a quirk of fate.  Back in the Triassic, this part of the world was a lush, tropical paradise, however, nearby volcanoes from time to time deposited vast amounts of ash in the area.  These ashes formed easily recognisable layers (called tuffs) and within these layers the scientists, which included researchers from the University of Buenos Aires, the University of Brasília (Brazil), along with American colleagues and collaborators from Argentina’s National Scientific and Technical Research Council, were able to identify microscopic crystals called zircons.  It is these zircon crystals that hold the key to accurate dating of geological deposits.

Zircon Crystals and Radiometric Dating of the Chañares Formation

The uniform decay of radioactive elements allows an accurate date of geological formations.

The uniform decay of radioactive elements allows an accurate date of geological formations.

Picture Credit: Everything Dinosaur

The research team took samples from the various ash layers and noted their position within the sedimentary beds and the vertebrate fossils associated therein.  Zircon crystals were identified within the volcanic layers and these were radiometrically dated using the ratio of uranium decay to lead isotopes.  In this way, thanks to advances in mass spectrometry the team were able to determine an accurate age of the zircon and by inference the age of the fossil bearing sedimentary layers above and below the ash layers.  The technique has been used before, for example to date the lower portions of the Chinle Formation of the United States (U-PB ID-TIMS zircon geochronology dating method [uranium to lead]).

So what would have been bad luck for the fauna and flora around at the time, a devastating deposit of choking volcanic ash, has permitted palaeontologists to be able to date with considerable accuracy the deposition timeline of this part of the Chañares Formation.

Identifying the Ash Layers for Sampling (Chañares Formation)

Co-author Adriana Mancuso (right) points to a volcanic ash layer (tuff) in the Chañares Formation that was sampled for radioisotopic dating.

Co-author Adriana Mancuso (National Scientific and  Technical Research Council) points to a volcanic ash layer (tuff) in the Chañares Formation that was sampled for radiometric dating.

Picture Credit: Randall Irmis (University of Utah)

What Does the Accurate Triassic Timeline Reveal?

It had been thought that the strata was around 226 to 228 million years old (early Late Triassic, the Carnian faunal stage).  However, this study indicates that these rocks were laid down much earlier in the Triassic, perhaps 5 to 10 million years earlier, making the rocks, effectively Middle Triassic in age (234 to 236 million years old, the Ladinian faunal stage).  Fossils of dinosaur precursors, known as dinosauromorphs, Archosaurs that are very closely related to the Dinosauria and the ancestors of the dinosaurs are found in these rocks.  The first dinosaur fossils date from around 230 million years ago approximately, perhaps even earlier.  This means that the true dinosaurs evolved from the dinosauromorphs much quicker than previously thought.  There was a much more rapid transition from a world with dinosauromorphs to a terrestrial ecosystem with dinosaurs in it.  In short, dinosaurs very quickly became established.

The Fossil Assemblage of the Chañares Formation (Schematic Diagram

Vertebrate fossils found include a range of Tetrapods including Dinosauropmorphs and Dicynodonts.

Vertebrate fossils found include a range of Tetrapods including Dinosauromorphs and Dicynodonts.

Picture Credit: Everything Dinosaur (inset photograph Randall Irmis)

Commenting on the significance of this new study, which has just been published in the Proceedings of the National Academy of Sciences (USA), Randall Irmis stated:

“To discover that these early dinosaur relatives were geologically much younger than previously thought was totally unexpected.”

What Does This Mean for Other Middle Triassic Formations Elsewhere?

This shift in the date for these deposits that make up a portion of the Chañares Formation has serious implications for other fossil-bearing strata that were also believed to represent the Middle Triassic.  Similar types of vertebrate fossil are found in the Santa Maria Formation (southern Brazil) and in the Karoo Basin (South Africa), but none of these formations have been radiometrically dated.  These too, could be 5 to 10 million years older than previously thought.

Summarising the research a spokesperson from Everything Dinosaur explained:

“The geological dates for certain fossil assemblages may have to be reconsidered in the light of these findings.  The evolution and subsequent radiation of the Dinosauria has become somewhat concertinaed.  This research suggests a much more rapid evolution from dinosauromorphs to true dinosaurs than previously thought.”

Why Did the Dinosaurs Evolve Rapidly?

The first dinosaurs believed to have evolved were the Saurischian Theropods.  These Archosaurs were bipeds and their skeletons show that they had an advantage over many of the other predators (bipedal and quadrupedal) around at the time.  Firstly, the pelvic area has a fully open acetabulum (the rounded hole in the pelvis where the head of the femur fits).  This allows the hind legs to locate much more directly under the body, providing a more efficient locomotion.  Secondly, the femur itself has a ball-shaped head turned slightly inward to slot into the acetabulum.  This arrangement, also supports the hind legs located directly under the hips.  These anatomical features, (plus one or two others), evolved to permit these Theropods to develop stronger legs making them faster and more powerful than other Archosaurs.  These strong legs seem to have enabled the dinosaurs to “sprint out of the evolutionary blocks”, leading to their domination of terrestrial ecosystems for the best part of 160 million years or so.

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