Return to the Carboniferous – take a trip to North Wales

The fossilised remains of gigantic tree-like plants are going on display at the Wrexham Museum as part of an exhibition entitled “From Coals to Carnations”.  The prehistoric fossilised trees, some of which were upwards of 40 metres tall once formed part of a dense swampland in which huge insects and the first reptiles thrived.

Fossilised Trees

The fossilised trees were first uncovered during overcast mining works on the site of a former steel mill near Wrexham in 2003.  The actual site is at the village of Brymbo, just a few miles to the north of Wrexham.  The fossilised finds demonstrate that approximately 300 million years ago the land that was to eventually form Wales was much closer the equator than today and made up part of a super continent called Laurentia that covered much of the Western Hemisphere.

Geologists have been working on the site since its discovery, but work was accelerated from 2006 as the exposed fossils formed from mudstone, began to be weathered and there were some concerns about losing these rare fossils.  More than 20 individual specimens have been identified, a number of which are going on display to the public for the first time at the Wrexham Museum.  These ancient plants date back from before the time of the dinosaurs, and before flowering plants.  They are the trunks of giant clubmosses like Lepidodendron.  The scientific name for clubmosses are Lycopsids, a number of clubmoss genera still survive today, but they tend to be very small, no match for their huge ancestors.

A Carboniferous Forest Scene

A museum exhibit showing a typical Carboniferous habitat.  Huge invertebrates such as Arthropleura roamed the forest floor.

Picture credit: Everything Dinosaur

Coal Deposits

As wood and other plant material was compressed and decayed it went onto form coal deposits.  The Welsh coal fields took approximately 20 million years to form, since the Industrial Revolution about 200 years ago, most of these coal fields have been exhausted.  A team of geologists helped oversee the preservation of the fossils, which had all been found at a site just 50 metres in length.  This land is designated for new housing and light industry, but the developer Parkhill Estates, after discussions with local lobbyists decided that they wanted to try to preserve as many of the fossil specimens as possible.

The Wrexham Museum exhibition will provide visitors with a rare insight into the area’s prehistoric past.

To view replicas and figures of animals from the Palaeozoic and other extinct creatures: CollectA Prehistoric Life Replicas.

Road Builders in Peru Discover Fossils

Peruvian construction workers have uncovered an array of body and trace fossils dating back to the age of the dinosaurs as they worked on a new road, one of the discoveries is a dinosaur trackway.  As well as dinosaur fossils, including some really well preserved footprints, the road workers found fossils of crocodiles, pterosaurs, primitive tortoises and remains of extinct species of fish.

Palaeontologists who have been called in to study the site have revealed that the remains of at least a dozen animals have been found, the sediments date back to the Early Cretaceous and have been dated to approximately 120 million years ago (Aptian faunal stage).

Dinosaur Trackway

Pictures show a set of four footprints, the prints have three prominent toes and the animal was walking from right to left as you look at the photographs.  Such prints are known as trace fossils.  Trace fossils preserve evidence of the activity of organisms, such as their tracks, trails, burrows or borings.  As these type of fossils are not subject to be moved by natural forces, as in the case of dinosaur bones for example, where an animal’s carcase can be moved a long way from where it died to where the body finally comes to rest and is fossilised, trace fossils are direct in situ evidence of the environment at the time and place the fossils were formed.

Unfortunately, as with most photographs of this type, there is nothing in the picture to give scale.  However, it does look like these particular prints were made by herbivorous ornithopod dinosaurs, perhaps something from the Iguanodontidae or a member of the Hypsilophodontidae.

These types of animals were relatively common during this part of the Cretaceous.  Iguanodontids have been associated with Australia, Asia, Europe, the UK and Africa.  Iguanodon for example, was one of the first dinosaurs to be scientifically described, although the taxon is currently under review.

Typical Ornithopods

Iguanodontids are typical ornithopods, with beaks, narrow mouths and banks of grinding teeth.  Most of these dinosaurs were heavily built quadrupeds, but also capable of walking on their hind legs.  The digits of the hands of the forelimbs were specialised and modified.  The thumb for example (digit one), was a large spike, probably used for defence.  The long, deep tail helped balance the animal as it walked.

An Illustration of Iguanodon

Picture credit: Everything Dinosaur

To see a model of Iguanodon and other ornithopod dinosaurs: Dinosaur and Prehistoric Animal Models.

Studying Dinosaur Tracks

By studying trackways, scientists can gain an appreciation of animal behaviour.  For example, if several tracks of a single species are preserved, all heading in the same direction this may indicate herding behaviour.  The velocity of the animal that made the tracks can be calculated using a formula and measuring the stride length and other items related to the leg speed of the animal.

The fossil site is located in the Ancash region of central Peru, approximately 250 miles north-east of Lima.  At a height of over 4,600 metres above sea level, this fossil dig site is believed to be one of the highest prehistoric fossil sites found to date.

Insight into the Isle of Wight during the Cretaceous

The Wealden Group of the Wessex Basin is exposed on the surface in the coastal cliffs of the Isle of Wight off the English south coast.  This strata is famous for its abundance of well preserved dinosaur fossils, both body fossils and trace fossils.

Dinosaurs and other prehistoric animals from the Mesozoic have long been associated with this island, but now a new study into the island’s ancient fauna and flora has helped provide fresh insight into the diversity of life during the reign of the dinosaurs.

Forty-Eight New Species

For Dr Steve Sweetman of the University of Portsmouth, the research has led to the identification of 48 new species of prehistoric animal including Deinonychus sized dromaeosaurs and large pterosaurs.  The work of Dr Sweetman and his colleagues has enabled scientists to fill in a number of gaps in the Early Cretaceous eco-system and provide much more detail than previously available on the smaller animals that shared the dinosaur’s habitat.

The Isle of Wight’s dinosaurs are globally significant; a large number of different dinosaur species have been discovered in the rocks that make up the island.  Most of the fossils date from approximately 135 – 130 million years ago (Hauterivian to Barremian Formation).  The island, during this part of the early Cretaceous was an extensive flood plain that linked the continents of Africa, Europe and what was to become the Americas.  The area formed a land bridge and as well as being a rich and fertile environment in itself it may have been on the migration route of many types of prehistoric animal.

Cretaceous Ecosystem

The number of new species discovered by Dr Sweetman and his team is remarkable, especially when all the work to prepare and identify the fossils, many of which are minute, has been undertaken in just 4 years.

Dr Sweetman’s haul includes eight dinosaurs, six mammals and fifteen different types of lizard all taken from cliffs of the Isle of Wight.  Thanks to his efforts we now have a better understanding of the eco-system and have the opportunity to study in more detail some of the smaller faunal types.

However, Dr Sweetman did find fossil evidence of brachiosaurs, the largest dinosaurs known from UK strata.

Rather than wait for fossils to be weathered out of the cliffs, he excavated a block of sediment approximately 3,500 kilogrammes in weight and then removed it all to a preparation area, where it was dried and then each individual grain was scrutinised.  As well as larger items such as fossil bone, he discovered tiny teeth, fossilised jaws and other micro-fossils that enabled him to build up a picture of life during the Early Cretaceous.

An Illustration of the Isle of Wight Cretaceous Fauna

Picture credit: Mark Witton

Systematic Working

Dr Sweetman explained that his technique was more comprehensive than traditional palaeontological methods and his systematic working has enabled such a rich picture of life to be built up.

“It has taken me just four years of hard graft to make my discoveries.  In the very first sample I found a tiny jaw of an extinct newt-sized, salamander-like amphibian and then new species just kept coming” he commented.

Dr Sweetman went on to add:

“Although we knew a lot about the larger species that existed on the island during the Early Cretaceous, no-one had ever filled in the gaps.  With these discoveries I can paint a really detailed picture of the creatures that scurried at the feet and in the shadows of the dinosaurs”.

This new study will cement further the reputation of the University of Portsmouth as well as reinforcing the belief that the Isle of Wight remains one of the most important sites in the world for Lower Cretaceous fossils.

For models and replicas of Early Cretaceous prehistoric animals: CollectA Prehistoric Life Models and Figures.

Fossil Skeleton of 45-foot long Snake Discovered in South America

With the mass extinction event that marked the end of the Mesozoic, those animals that remained, rapidly diversified and took up most of the ecosystem niches left vacant by the demise of the dinosaurs.  Mammals rapidly evolved and diversified and soon all the Orders that we know today were established.  However, those reptiles that had outlasted the dinosaurs also took the opportunity to exploit new environments and those places in the food chain left empty by the dinosaurs.

Fossils of one of the largest snakes known to science have just been unearthed in South America, and this new snake named Titanoboa would have probably been the apex predator in its jungle environment.

Titanoboa

The Palaeocene epoch lasted approximately 10 million years (65-55 million years ago).  The world slowly recovered from the catastrophes that had led to the extinction of approximately 60% of the life on Earth.  Within a few hundred thousand years of the end of the Mesozoic, planet Earth was covered in lush rain-forest, jungle and swamps.  Global temperatures rose to an average of 28 degrees Celsius and humidity increased permitting gigantism in creatures as diverse as insects, birds and reptiles.

“Hot House Earth”

Our planet had not experienced such a “hot house” environment since the Jurassic and those types of animals that had survived the extinction event soon found themselves in a lush, warm, humid environment, so warm in fact that tropical rain-forest and jungle stretched from the tips of Chile and South Africa right up to beyond the Canadian border.

European countries such as Germany and Poland had similar climates as did much of China in the east.  Even the United Kingdom was covered in tropical rain-forest (hard to believe considering the icy conditions that we have had this week).

With cold-blooded animals such as snakes, the temperature and availability of food can affect the potential size of a species. With such a warm climate, the absence of major predators such as the Theropod dinosaurs, snakes were able to exploit the conditions and truly huge forms began to evolve.

A New Genus of Snake

The fossils of this new genus of snake, believed to be a constrictor like a boa or the giant Anaconda of South America, were found at an open cast mine in north-eastern Columbia.  Along with the giant bones of the snake, fossils of crocodiles and turtles were also discovered, perhaps these other reptiles made up a large part of this Titanoboa’s diet.

An Artist’s Impression of Titanoboa

Picture credit: Jason Bourque

Estimating the Size of Titanoboa

Estimating the size of the snake based on comparisons with extant species indicates a length of 15 metres with a weight in excess of 1,200 kilogrammes.  Fossils of large snakes have been discovered in South America before.  An example would be Madtsoia bai, a huge constrictor known from fossils discovered in Argentina in the mid 1930s.  This particular species was believed to be up to 12 metres long, huge by modern snake standards but still 20% smaller than Titanoboa.

Commenting on the new discovery, Jack Conrad a snake expert at the American Museum of Natural History in New York stated:

This thing [Titanoboa] weighs more than a bison and is longer than a city bus.  It could easily eat something the size of a cow.  A human would just be toast immediately”.

The details of this discovery is published in this week’s edition of the scientific journal “Nature”.

Titanoboa cerrejonensis

The species has been formally named Titanoboa cerrejonensis, the name means “titan boa from the Cerrejon”, the region of Columbia where the snake fossils were found.  Although, probably more closely related to boas such as the Royal Python, this snake probably behaved more like an Anaconda, being at home equally well in water and on land.

The Boas (family Boidae), are considered to be relatively primitive in comparison with venomous snakes that make up the order Squamata such as vipers.  Scientists believe that snakes such as Boas evolved from lizards during the Late Cretaceous and snakes were constrictors at first, then eventually venomous forms evolved.

Boas retain several features that link them to their lizard ancestors.  For example, most species of boa retain a pelvic girdle and traces of the hind-limbs are found in a number of species.  The vestigial hind-limbs have been reduced to cloacal spurs in many types of boa, these can be seen on males.  Members of the Boidae family also retain the coronoid bone in the lower jaw, another link to their lizard ancestry that has been lost in higher snakes.

Titanoboa can make a claim for being the largest snake known to science.  When its fossilised bones are compared to those of a 6 metre Anaconda the true scale of this beast is revealed.

Comparison of Fossilised Titanoboa Vertebra with Extant Anaconda

Picture credit: Nature

Huge Fossil Vertebra

The huge fossil vertebra of Titanoboa dwarfs the vertebra of a modern Anaconda.  When alive Titanoboa would have been about as thick as an oil drum, making it a fearsome predator.

The beast was revealed in early 2007 at the University of Florida’s Florida Museum of Natural History in Gainesville.  Fossils collected at a huge open-pit coal mine in Colombia were being unpacked by graduate students and they realised that they were unwrapping the fossilised bones of something spectacular.  To date the scientists have identified about 180 different bones, mainly vertebrae and costae (rib bones).  These remains are believed to represent about a dozen individuals.

It seems that gigantic, fearsome reptiles did not disappear from our planet with the extinction of the dinosaurs.  Some types of reptile exploited the Palaeocene environment to evolve into new types of nightmarish creature.

Rebor Replicas

The model manufacturer Rebor has made several replicas of Titanoboa.  To view the figures (whilst stocks last): Rebor Replicas and Models.