Category: Photos/Pictures of Fossils

Giant Ordovician Filter Feeder Provides Clues to Arthropod Evolution

Two Metre Long Aegirocassis benmoulae Expands Ecological Role of Anomalocarids

A beautifully preserved fossil of a giant Arthropod from Morocco is helping palaeontologists to gain a better understanding of the evolution and the development of the Arthropoda as well as providing a new perspective on the fauna that formed an extensive and diverse ecosystem in an Early Ordovician sea.

The Arthropoda are the largest phylum in the Kingdom Animalia and the first fossils of these segmented creatures with their hard, external skeletons date from the Early Cambrian.  Characteristics of these animals include that exoskeleton, a segmented body plan and paired, jointed appendages that can perform a variety of functions, such as swimming, walking and feeding.  Typical Arthropods include crustaceans, spiders, king crabs, scorpions, mites and insects, all very familiar to us today. Extinct forms include the Trilobita and the anomalocarids, one of which turns out to be a two metre long giant that fed like a baleen whale.

A team of researchers including scientists from Yale University and the University of Oxford have been examining the three-dimensional remains of this strange, new type of anomalocarid in a bid to understand how the Arthropods diversified and those highly adaptable paired, jointed appendages first evolved.  It could be argued that it is the Arthropods that dominate animal life on our planet.  As a phylum they have adapted to a huge range of different habitats and they make up over eighty percent of all described animal species.  Enter into the debate, a newly described anomalocarid named Aegirocassis benmoulae.  The anomalocarididae family are long-extinct.  However, they are regarded as basal members of the Arthropoda and their fossil record extends from the Cambrian into possibly the Devonian, although Devonian anomalocarids remain a controversial area of palaeontology due to differing interpretations of fossil material.   These marine creatures grew to very large sizes in relation to other marine fauna and the majority of them were nektonic predators.  However, A. benmoulae evolved in a very different direction.

An Illustration of the Giant Aegirocassis benmoulae – Filter Feeder of the Early Ordovician

An early, filter-feeding giant.

An early, filter-feeding giant.

Picture Credit: Marianne Collins, ArtofFact

The anomalocarids were like no living animal today.  The mouth was circular on the underside of the head and surrounded by frightening, jagged (in most cases) hard tooth plates, designed for crushing the exoskeletons of other Arthropods.  The large, compound eyes gave these active hunters an excellent all-round field of vision and at the front of the head was a pair of spiny, grasping appendages used to grab prey.  Their elongated, segmented bodies had flaps on the side that were used for propulsion.  Until the discovery of A. benmoulae it had been believed that anomalocarids had only one set of flaps per body segment and that they had completely lost their walking legs.

The fossils, which have been preserved in three dimensions, an extremely rare preservation state for an Arthropod, come from the Draa valley in south-east Morocco.  The sediments were formed at the bottom of a deep sea and the strata has provided palaeontologists with an insight into life in the Early Ordovician.  Very occasionally violent storms disturbed the seabed and buried large numbers of animals.  These events led to the formation of a very rich Lagerstätten, which has helped scientists to map the pace of evolution from the Cambrian explosion some sixty million years before these fossils formed to the end of the Ordovician some 443 million years ago.  The fossils from this part of Morocco form the Fezouata Biota, representing a marine habitat dating from around 485-480 million years ago.

To read about the discovery of a giant, predatory anomalocarid from the same region of Morocco: Giant Marine Predator of the Ordovician

The description of Aegirocassis benmoulae provides new evidence for Arthropoda evolution.  The exquisite preservation reveals that anomalocaridids had in fact, two separate sets of flaps per segment.  The upper flaps equate to the upper limb branch of modern Arthropods, while the lower set of flaps represent modified walking limbs that were adapted for swimming.  A reassessment of older anomalocarid fossilised remains also show two separate flaps per body segment.  The scientists have concluded that the anomalocaridids represent a stage of Arthropoda evolution before the fusion of the upper and lower appendages that form the double-branched limbs of extant Arthropods.

Peter Van Roy, an associate research scientist (Yale University) and an authority on the Fezouata Biota stated:

“It was while cleaning the fossil that I noticed the second, dorsal set of flaps.  It is fair to say I was in shock at the discovery and its implications.  It once and for all resolves the debate on where anomalocaridids belong in the Arthropod tree and clears up one of the most problematic aspects of their anatomy.”

As if to reflect the adaptability of the Arthropoda bauplan, it seems that this Moroccan giant evolved to exploit the abundance of small marine organisms that flourished in the Early Ordovician.  The head appendages that formed the spiky, grasping claws of this anomalocarid became modified into delicate filter feeding apparatus.  It is likely that this creature cruised the oceans feeding on tiny plankton and other organisms floating on the currents just like modern baleen whales, manta rays and whale sharks.

A Close up Showing the Delicate “Fronds” of the Filter Feeding Net

Delicate feeding apparatus.

Delicate feeding apparatus.

Picture Credit: Peter Van Roy (Yale University)

The picture shows a close up of the prepared fossil material showing the delicate fronds which the creature used to sieve sea water for food (scale bar = 10 mm).

Commenting on the implications for Early Ordovician ecosystems, c0-author of the scientific study, Dr. Allison Daley (Oxford University’s Department of Zoology) stated:

“These animals are filling an ecological role that hadn’t previously been filled by any other animal.  While filter feeding (filtering water to find food) is probably one of the oldest ways for animals to find food, previous filter feeders were smaller, and usually attached to the sea-floor [benthic].  We have found the oldest example of gigantism in a freely swimming filter feeder.”

Carnivorous Plant Remains Found Preserved in Amber

The Mystery of The Very First Carnivorous Plant Fossil Leaves

Some types of organism, despite having been on our planet for tens of millions of years have such a poor preservation potential that they rarely, if at all appear in the fossil record.  One such group are the carnivorous plants, be they Venus Fly Traps, Sundews or Pitcher plants.  The trapping structures are often derived from primary growth, this reduces the preservation potential and these types of plants tend to be found in areas such as peat bogs and tropical forests where rapid breakdown of organic material occurs.  Up to now, carnivorous plant fossils have consisted of micro-fossils such as preserved pollen with the occasional fossil seed.  However, a team of scientists from the Botanical State Collection of Munich as well as Bielefeld and Göttingen Universities have found the first fossils of a proto-carnivorous plant preserved in Baltic amber.  Two leaves, trapped in pine resin over between thirty-five and forty-seven million years ago, have been identified to belonging to the family of flypaper plant traps.  These types of plant produce sticky substances that trap small insects and other Arthropods.

The sticky hairs on the leaves can be clearly made out under a microscope.  The amber was found in a mine near Kaliningrad, the Russian enclave on the Baltic coast.  Amber from this part of the world, referred to as Baltic amber is relatively common and remarkably as amber floats in sea water, from time to time pieces of Baltic amber are washed up on the coast of East Anglia (United Kingdom).

The Fossils of a Carnivore (Roridula spp.)

Leaf remains trapped in amber.

Leaf remains trapped in amber.

Picture Credit: PNAS and University of Göttingen/Alexander Schmidt.

Writing in the Proceedings of the National Academy of Sciences (United States), the research team led by Professor Alexander Schmidt (University oGöttingen), have identified the leaves, with their long-stalked multicellular glands as being reminiscent of extant plant species in the Roridula family.  Plants in the family Roridulaceae are not true carnivorous plants in the strictest botanical sense.  In contrast to the likes of the Venus Fly Trap (Dionaea spp.), Roridula do not trap, kill and digest their animal prey.  These plants are not capable of producing the enzymes required to breakdown the bodies of their victims.  Instead, they rely on a symbiotic relationship between types of carnivorous Heteropteran insects (bugs), that feed on the trapped organisms.  In turn, the nutrient rich excretions from these scavengers are absorbed by the plant through its leaves.

Today, living members of the carnivorous plant Roridula are restricted to southern Africa, however, during the Eocene these plants must have been much more widespread.  For much of the Eocene Epoch, the world was warmer than it is today.  The discovery of these fossils provides a mystery for the research team to solve.  Firstly, it suggests that the flora in the forests that were to produce the tree resin that was to eventually become amber, must have been more diverse than previously thought.  Secondly, it had been thought that the ancestors of the Roridula evolved around 90 million years ago in Africa and these plants evolved in isolation as Africa became separated from other land masses as the southern super-continent of Gondwanaland broke up.

However, as Professor Schmidt points out:

“The new fossils from Baltic amber show that the ancestors of Roridula plants occurred in the northern hemisphere until around 35 million years ago, they were not restricted to South Africa.”

These plants seem to be have been more widespread than previously thought, the fossils also confirm molecular dating that hypothesised that these types of plant had been distinct from other plant families for at least 38 million years.

Everything Dinosaur acknowledges the help of the University oGöttingen in the compilation of this article.

Mary Anning at the Natural History Museum

Being Associated with the Wrong Marine Reptile

As team members from Everything Dinosaur travel around they sometimes get the chance to visit a natural history museum whilst out on their adventures.  There are many splendid museums in this country and elsewhere in the world and it is great fun looking at the various fossils held within the collections.  Occasionally, we come across an exhibit that has inaccurate or out of date information, mistakes do occur and we are always appreciative of the time and trouble curators take over their particular charges.

One such anomaly can be seen in the Fossil marine reptiles gallery in the Natural History Museum London.  There are some spectacular marine reptile fossils on display, Ichthyosaurs, Pliosaurs and their close cousins the Plesiosaurs.  The fossil specimens (most of them are casts) are truly astonishing and this museum (quite rightly in our opinion), does much to acknowledge the contribution of Mary Anning to the nascent science of palaeontology and her work excavating and describing fossils of ancient Jurassic marine vertebrates preserved in the cliffs on the Dorset coast around Lyme Regis.

Information about Mary Anning and her work can be found on various information boards on display.  However, one thing that has always puzzled us is that there is a prominent information board about Mary located on the Rhomaleosaurus cramptoni cast, Mary Anning had nothing to do with this specimen, its discovery or research into it.  In fact, she died about a year before this specimen was found.

Wonderful Marine Reptile Exhibits – but Nothing to Do with Mary Anning

Mary Anning died before this fossil was discovered.

Mary Anning died before this fossil was discovered.

Picture Credit: Everything Dinosaur/Rebor

The specimen in the photograph is not a fossil but a cast, a copy of the fossil which was made very probably in the late 19th Century by the American Henry Augustus Ward, who set up one of the world’s first fossil dealers and provider of museum replicas and casts.  The animal that the cast represents is called Rhomaleosaurus cramptoni.  It is pronounced Row-ma-lee-oh-sore-us.  It is mounted on the wall of the fossil marine reptiles gallery in the Natural History Museum, but we are aware of similar casts of the same fossil specimen in Monash University (Victoria, Australia), Cornell University, (New York USA), University of Illinois,  and the Bath Royal Literary and Scientific Institution (Bath, Somerset).

The actual fossil is part of the National Museum of Ireland (Natural History), Dublin, Ireland, we don’t think it is on current display.  The code for the specimen is NMING F8785 (all significant fossils are given a unique identifier, this helps when searching for information on a particular specimen).

A Model of the Fearsome Rhomaleosaurus cramptoni

A super model of a marine reptile.

A super model of a marine reptile.

Picture Credit: Everything Dinosaur

Rhomaleosaurus means “strong lizard” an appropriate name for this fearsome predator that grew to more than six metres in length and might have weighed as much as 1,000 kilogrammes.

Fresh Rockfalls at Monmouth Beach (Lyme Regis)

Warnings for Fossil Hunters at Lyme Regis

The cliffs that surround the picturesque town of Lyme Regis in Dorset on England’s famous “Jurassic Coast” are very treacherous.  Rockfalls and landslips are a relatively common occurrence and team members at Everything Dinosaur, have done much to help inform and to warn visitors to the area of the potential hazards.  Fossil collecting or simply exploring the beaches can be a lot of fun, but the recent cliff fortification and shore stability measures put in place by the local council will not solve the problem of the unstable geology of the area.   The cliffs are composed of relatively loose sediment, that when saturated after heavy rain or somewhat dried out after a prolonged spell without too much precipitation, are prone to rockfalls.  It is always advisable to stay well away from the base of the cliffs, fossil collecting on a falling tide helps, as this gives an increasing distance between the sea and the cliffs.

Dangerous Cliffs at Lyme Regis

Good idea to go fossil collecting on a falling tide and to keep away from the steep cliffs.

Good idea to go fossil collecting on a falling tide and to keep away from the steep cliffs.

Picture Credit: Everything Dinosaur

Recently, we were sent some photographs by Lyme Regis fossil expert, Brandon Lennon.  The photographs showed a rockfall that had taken place on Monmouth beach (to the west of Lyme Regis).  Brandon explained that he had observed a number of cliff falls this year and that he expected more to occur as the autumn weather sets in.   This particular rockfall had occurred on that area of the beach famous for its extensive ammonite and nautiloid fossils preserved within the blue lias limestones – an area known as the “Ammonite Pavement” or the “Ammonite Graveyard”.

Recent Rockfall at Monmouth Beach

Rockfall onto the Ammonite Pavement on Monmouth Beach.

Rockfall onto the Ammonite Pavement on Monmouth Beach.

Picture Credit: Everything Dinosaur

A supervised, fossil collecting walk is one of the best ways to explore the beaches around Lyme Regis, for further information on such tours: Fossil Walks in the Lyme Regis Area

Perhaps if you are lucky enough to go on a field trip with Brandon to Monmouth beach, you might be able to hear the theories that have been proposed to help explain why so many large ammonite fossils are found together at this spot.

Everything Dinosaur was sent a beautiful piece of fossilised wood from nearby Portland.  The specimen still had the bark preserved on it and when polished in section, growth rings could still be made out. We think that the fossil represents an Araucaria spp. (monkey puzzle tree).  This fossilised wood dates from the Upper Jurassic.  Fossil wood can occasionally be found on the beaches of Lyme Regis and nearby Charmouth, but this is usually much older dating mainly from the Lower Jurassic.

A Polished Section of Fossilised Wood

A polished section of fossilised wood.

A polished section of fossilised wood.

Picture Credit: Everything Dinosaur

Remember if fossil collecting, be careful out there.

Ancient Creepy-Crawlies Resurrected

410 Million Year Old Arachnid Walks Again

A team of international researchers have used fossils of ancient Arthropods from the London Natural History Museum to recreate the movements of some of the world’s first terrestrial predators.  Researchers from the Museum für Naturkunde (Berlin) and Manchester University have used an open source computer programme called Blender to model the walking motion of a 41o million year old ancient Arachnid.  The video shows the most likely gait that this tiny prehistoric predator could achieve as it stalked across the Devonian landscape.  The paper, which details this research has been published in a special edition of the academic publication the “Journal of Palaeontology”.

The scientists took minute slices of the fossils of these early Arachnids and once the limb segments and their joints had been identified they worked out the range of limb motion possible.  From these measurements and using comparisons with extant Arachnids, the researchers modelled the walking action using the Blender software programme.  In this way, a creature dead for over 410 million years could once again walk.

Dr. Russell Garwood, (palaeontologist at Manchester University), stated:

“When it comes to early life on land, land before our ancestors came out of the sea, these early Arachnids were top dog of the food chain.  They are now extinct, but from about 300 to 400 million years ago, they seem to have been more widespread than spiders.  Now we can use the tools of computer graphics to better understand and recreate how they might have moved – all from thin slivers of rock, showing the joints in their legs.”

Supplemental Data Video 2 – Palaeocharinus Locomotion

Video Credit: University of Manchester Press Room

The video shows the ancient Arthropod (Palaeocharinus genus) walking.  Although a formidable looking animal, this early creepy-crawly was less than half a centimetre in length.  The fossils used in this study came from the famous Lower Devonian strata at Rhynie (Aberdeenshire, Scotland).  The Rhynie chert deposit contains evidence of one of the earliest terrestrial ecosystems known to science.  More than twenty primitive plant species have been identified along with Arthropods such as mites and trigonotarbids such as Palaeocharinus that hunted amongst the miniature forest made up of Rhyniophytes (primitive plants).

Co-author of the scientific paper, Jason Dunlop (Museum für Naturkunde), added:

“These fossils,  from a rock called Rhynie chert, are unusually well-preserved.  During my PhD I could build up a pretty good idea of their appearance in life.  This new study has gone further and shows us how they probably walked.  For me, what’s really exciting is that scientists can make these animations now, without needing the technical wizardry and immense costs of a Jurassic Park-style film.”

Although not true spiders, trigonotarbids are related to modern spiders but they lack certain spider features such as silk producing spinnerets.  As a group, they first appear in the fossil record in the Late Silurian.  The oldest trigonotarbid specimen, that we at Everything Dinosaur know about, comes from the Upper Silurian deposits of Ludow , Shropshire (Ludlow epoch around 420 million years ago).  It was Jason Dunlop who was responsible for describing this discovery (1996).

A Highly Magnified Image of a trigonotarbid (Palaeocharinus)

The highly magnified section shows leg segments clearly.

Picture Credit: Everything Dinosaur

The scale bar in the picture represents 2 mm.

Dr. Dunlop stated:

“When I started working on fossil Arachnids we were happy if we could manage a sketch of what they used to look like, now we can view them running across our computer screens.”

The development of sophisticated computer programmes is permitting scientists to re-create three-dimensional images of spectacular fossils.  In addition, new generation programming technology is now capable of bringing long extinct creatures back to life, at least in cyberspace.  The predatory Palaeocharinus might be quite frightening, but at half a centimetre long it would probably not even had got a second glance if you spotted on in the garden.  However, other specimens from Upper Devonian strata, as yet not fully described fossils, indicate that there were much larger creatures at home amongst the primitive plants such as the Rhyniophytes and Lycopsids (clubmosses), some fossils indicate Arthropods nearly an inch in length.  These creatures may not be trigonotarbids but perhaps represent an entirely new family of Arthropoda.

Dr. Garwood concluded:

“Using open source software means that this is something anyone could do at home, while allowing us to understand these early land animals better than ever before.”

Everything Dinosaur acknowledges the help of the Faculty of Engineering and Sciences (University of Manchester) in the compilation of this article.

Seeing Fossils Everywhere

Spotting Objects that Resemble Fossils

One of the drawbacks of working with so much fossil material is that after a while team members at Everything Dinosaur tend to see examples of fossils in everyday objects.  We tend to call these “pseudofossils”.  The term pseudofossil is used to describe an object that resembles a body or trace fossil when it is not.  These misleading structures can be found throughout nature.  For example, Everything Dinosaur staff are often shown photographs of paving blocks which the owner claims show a fossil, but these strange patterns in stone are produced by crystals of manganese oxide coming out of solution as water passes through cracks in the rock.  The crystals align themselves in the direction of water flow and often resemble a plant fossil, such as fern in appearance.

We do our best not to leave the bearer of the photograph too dejected, after all, we do point out that the arrangement of the crystals in the stone is unique and there is not another one like it in the whole of the world.

Whilst visiting a trade show, one of the Everything Dinosaur team spotted a delightful tea-light, the fern like appearance of this wall mounted fitting reminded us of the Late Precambrian marine organism Charnia (Charnia masoni)

Tea-Light that Resembles Precambrian Charnia

Every day objects remind Everything Dinosaur staff of fossils.

Every day objects remind Everything Dinosaur staff of fossils.

Picture Credit: Everything Dinosaur

Charnia was a deep-sea, organism whose fossils have been found in Late Precambrian strata in Leicestershire, Australia, Canada and Russia. The first fossil of this strange type of primitive animal, perhaps a colonial animal, was identified from a specimen found by a school boy called Roger Mason in Charnwood Forest (Leicestershire).  Scientists remain uncertain as to what type of organism the this animal was.  It was certainly an animal, as it grew at depths of more than two hundred metres deep, well beyond the depth at which sunlight could penetrate so no photosynthesising plants could exist.  Charnia has bilateral symmetry and is composed of a series of branching, feather-like fronds.  It seems to have been benthic (living on the sea floor), held in place by a disc-like, holdfast mechanism. It has been suggested that this animal may have been ancestral to modern sea pens, but the exact phylogenetic relationship between this 550 million year old organism and modern Phylum remains hotly debated.

One thing that is now known and agreed upon by most palaeontologists, Charnia-like organisms may have been relatively common in the deep-water environments of Late Precambrian seas.

To read an article, related to Sir David Attenborough and the relative abundance of Charnia specimens now being revealed: Spotlight on Fossil Discoveries from Leicestershire (Happy Birthday Sir David)

Seeing the shape and colouration of the tea-light reminded us of the story of Charnia and of how much we have to learn about the origins of life on Earth.

Back into the Fold – Fossils Found

Retrieving Ammonite Fossils

Lost but then they were found.  We have been sent two Ammonite fossils (Dactylioceras spp.) that were part of our extensive collection of fossils from Lower Jurassic strata of North Yorkshire.  Although these Jurassic fossils of Cephalopod Molluscs are common and we do have lots of Ammonite fossils in our collection it was great to see these two specimens again.

Ammonite Fossils Back in Everything Dinosaur’s Collection

Back into the Fold

Picture Credit: Everything Dinosaur

Such fossils have become part of ancient folklore, they are referred to as “snakestones”.    The snakestone term is believed to have come from the Whitby area (North Yorkshire), although there are references to such stones from Somerset as well.  The Whitby connection is that the Saxon Abbess St Hilda, on finding an area of land infested with snakes, turned all the reptiles into stones so that an abbey could be built.  As locals wondered why no heads of the snakes had been preserved, only the coiled bodies, heads were often carved onto specimens to make them look more authentic.  Some holotype specimens making up important museum collections have a snake carving on them, we think the holotype for the Ammonite species Dactylioceras commune may be such an example.

There were no snake heads preserved as these fossils are the chambered, coiled shells of Cephalopods related to cuttlefish and squid.

Ichthyosaurus Coprolite

A Picture of Coprolite from a Marine Reptile

At the request of several blog site readers, Everything Dinosaur has posted up a picture of the coprolite (poo) of an Ichthyosaur.

The Picture of the Coprolite

Marine reptile poo.

Picture Credit: Everything Dinosaur

We at Everything Dinosaur obviously aim to please our readers.

A Picture of a Fossilised Fish

A Picture of a Fossilised Fish

A Picture of a Fossilised Fish

Preserved fossil fish, found in a core drilling sample.

Picture Credit:University of Alberta

The picture above is of the Cretaceous teleost that was found in an oil drill core sample.

Silurian Fossils (Ludlow, Shropshire)

Everything Dinosaur Fossil Hunting Trip to Shropshire

Everything Dinosaur team members went on a special fossil hunting trip to a quiet location in the heart of the Shropshire countryside.  We found lots of fossils as the picture below shows:

A Successful Fossil Hunting Trip with Everything Dinosaur

Silurian Fossils from Shropshire

Picture Credit: Everything Dinosaur

Some Brachiopod fossils (Ludlow Series, Much Wenlock Formation), an example of the fossils found on a recent visit to the Mortimer Forest (south Shropshire, England), by Everything Dinosaur team members.

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