Incredible Fish Fossil found in Oil Drill Core

Sometimes a scientific discovery can be down to pure chance.  Despite huge advances in the technology available to palaeontologists, the finding of a brand new species can have more to do with serendipity than with appropriate planning and correct scientific practice.

The discovery of a new species of Late Cretaceous fish is a typical example of how “lady luck” can intervene and help scientists shed more light on life in the Mesozoic.  In 1988, a Canadian oil company called Cequel Energy Inc. was sinking drill cores into a region of west-central Alberta, prospecting for fossil fuels.

A 75 mm wide drill was thrust more than 1,300 metres deep into the Albertan sediments.  When the drill core was pulled up and examined it revealed a beautifully preserved 96 million-year old fossil fish, neatly encircled by the cylindrical drill core.  Only the tip of the snout and the last part of the tail had been lost, the rest of the fish fossil neatly fitted into the diameter of core sample.

One very lucky fossil find – a Cretaceous Teleost

Picture courtesy of University of Alberta

Occasionally core samples do reveal fossils, such as the Plateosaur fossil fragments extracted by an oil company offshore Norway in May 2006, but to find a delicate fish fossil such as this is a particularly rare event.

To read about the Plateosaur remains found in the Nowegian drill core:

Norway’s First Dinosaur – Say Hello to Plateosaurus.

Fish skeletons are light and fragile, even if they avoid being scavenged and are rapidly buried, wave action and currents can quickly disperse the bones as the flesh rots away.  However, in this instance the skeleton is virtually complete and perfectly preserved providing further evidence on the evolution of teleosts.

The core was taken from an area of Alberta just south of Grande Prairie, the fossil was found in core material from the Dunvegan Formation and as a result of this the fish has been named Tycheroichthys dunveganensis (means lucky fish from the Dunvegan Formation).  This deep-bodied fish belonged to a now extinct group called the Paraclupeidae, which are related to modern herrings.  Fish fossils from this group have been found in Lebanon and Brazil but this is the first time that this family have been reported from North America.

This fish has been referred to as a holotype (a specimen on which the original description of the species will be based).  During the latter part of the Cretaceous, North America was effectively split in two by the shallow Western Interior Seaway.  This sea stretched from the Gulf of Mexico to the Arctic Ocean covering the majority of Alberta during the late Cretaceous (with a few notable exceptions such as the Dinosaur Provincial Park Formation and the Oldman Formation).

The fish fossil lay amongst the other core samples for many years, under the supervision of the Canadian museum of Nature.  Palaeontologists from the University of Alberta reviewed the core samples and realised the significance of the fish fossil.  Their work on this amazingly lucky find has just been published in the Canadian Journal of Earth Sciences.

Articulated specimens such as this are extremely rare and given the circumstances of its discovery, it really is remarkable how this little fish fossil has survived.  The fossil has now been treated to help its preservation and stored in the secure vaults in the Canadian museum.

For models and replicas of prehistoric sharks and other ancient fish: PNSO Age of Dinosaurs Figures.

Did Two Asteroids colliding in Outer Space seal the Fate of the Dinosaurs?

In 1980 the physicist Luis Alvarez and his son, geologist Walter Alvarez proposed a theory that an asteroid hitting the Earth might have caused the mass extinction that led to the demise of the dinosaurs.  High levels of the rare Earth element iridium had been found in sediments dating from the Late Cretaceous and this led the father and son team to postulate that an asteroid impact could have wiped out much of life on Earth 66 million years ago.

Impact from Space

Their theory was given further credence with the discovery, in 1990, of a huge impact crater found off the coast of Mexico.  Could this be the “smoking gun” evidence of an asteroid impact that led to the extinction of the dinosaurs?

The impact crater, now known as the Chicxulub crater (a Mayan word that translates to “tail of the devil”) is estimated to have been 112 miles (180 kilometres) across and was made by an object of around 6 miles in diameter (10 kilometres).  Evidence now suggests that there may have been a series of impacts around 65 million years ago.  Such a catastrophic bombardment would have resulted in global environmental damage, huge fires, acid rain and mega tsunamis.  Not surprisingly then that approximately 70% of life was wiped out.

This theory has been largely accepted by the scientific community, but debate has arisen as to where this asteroid object came from.  Now new research by a joint US and Czech team, published in the journal Nature points to an event between 140 mya (million years ago), and 180 mya that set in motion the asteroid collision that would spell doom for the non-avian dinosaurs.

Asteroid Collision

A collision between two large asteroids in an orbit between Mars and the outer planets may have sent huge splinters of rock hurtling towards Earth, including the one that hit 65 mya claims the team from the South-west Research Institute of Colorado.

The three researchers, William Bottke, David Vokrouhlicky and David Nesvorny created a computer simulation that plotted the paths and direction of many large objects in what is known as the “Asteroid Belt” between Mars and Jupiter.  The orbit of one large terrestrial object known as (298) Baptistina intrigued them, as it shared the same orbital path with a lot of smaller asteroids.

Using the computer model to study the trajectories of these objects in the past, the team noted that the Baptistina asteroid and these other rocks were once joined together as a giant asteroid over 100 miles across, cruising the innermost region of the asteroid belt.  Their studies showed that between 140 mya and 180 mya (160 mya is the time period stated with most confidence by the researchers), a time when dinosaurs were dominating the Jurassic period – this huge asteroid was “bumped” into by another monster rock some 37 miles across (60 kilometres).

For a lesson plan relating to asteroids and extinction events designed for Key Stage 1 and Key Stage 2 students: Why Do Asteroids Always Land in Craters?

From this soundless collision was born a huge cluster of rocks, including 300 bodies larger than 6 miles in diameter (10km) and 140,000 bodies larger than 1/2 mile in size.  Over the remainder of the Mesozoic these rock pieces found new orbits under the influence of the Yarkovsky effect (named after the Russian engineer who identified this phenomenon), thermal particles from the Sun give objects momentum.  As the group of rocks spread out, at least some of them were captured by the gravitational pull of the inner planets and they began their journey with many impacting on Mars, Earth and Venus.

One such lump ended up colliding with Earth and causing the Cretaceous/Tertiary mass extinction.  The joint US and Czech team identify other celestial craters that may have been caused by debris from the Baptistina collision, a number of craters on Venus may have been as a result of this event and the huge moon crater Tycho estimated to be 108 million years old may also have been caused by an asteroid sent on its course by the initial impact 250 million miles away and approximately 60 million years earlier.

For dinosaur themed toys, clothing and gifts: Visit Everything Dinosaur’s On-line Shop.

Beetles with Chemical Weapons from the Age of Dinosaurs

Palaeontologists at Oregon State University have discovered a Cretaceous soldier beetle trapped in amber at the very moment it was operating its chemical defences to ward off an attacker.  This is the earliest known fossil of this type of beetle and the first time that this sort of defensive behaviour has been captured in the fossil record.

Cretaceous Soldier Beetle

The soldier beetle, a relatively small insect by modern soldier beetle standards at just over 6mm long was apparently on a tree when it was threatened by a much larger insect, perhaps some sort of cockroach (judging by the long antenna also preserved in the fossil tree resin).

The preserved antenna indicate the attacker’s length at being between 50-75mm but that did not deter the soldier beetle as it operated its chemical defences, oozing a sticky, irritating substance from its abdomen in a bid to protect itself from becoming a meal.  At the very moment the attack was launched, the soldier beetle was encased in tree sap which over millions of years formed amber, thus preserving this moment in time, allowing scientists to study it.

It is not known whether the attacking insect got away from the gooey sap as it crept down the tree trunk, only the antenna were trapped with the soldier beetle.

The Remains of the Attacker

Perhaps the remains of the attacker have also been preserved in another, now detached piece of amber, or more likely the larger insect was able to pull itself clear before becoming totally immersed in the adhesive sap, loosing its large antenna in the process.

The amber fossils date from approximately 100 million years ago (Cretaceous period) and have been sourced from Hukawng valley in Myanmar (formerly Burma).  Professor George Poinar Junior, a visiting professor of zoology at Oregon State University and an expert in interpreting insect remains preserved in amber, led the research.  His team’s findings have just been published in the Journal of Chemical Ecology.

A book review by Everything Dinosaur (fossil insects): Fossil Insects Book Review.

The scientists state that this discovery is the earliest fossil record of a chemical defence mechanism, indicating that this type of protective response, now common in insect taxa and amongst other animal species has been around for more than 100 million years.

Chemical Defences

Not only was this soldier beetle able to produce a chemical defence but close, microscopic study of the specimen indicates that the substance was only being released from the left rear of the insect.  This may indicate that soldier beetles during the Cretaceous had already developed the ability to control the direction of release, making this an already highly evolved and sophisticated defensive mechanism.

Professor Poinar commented that the chances of this type of behaviour being caught in tree sap and then having appropriate environmental conditions to permit preservation of this event as amber, plus the chances of the amber being found and brought to the attention of scientists to study – were extremely remote.  However, remarkable finds such as this one do turn up and give palaeontologists the opportunity to look through a window and observe events from the age of reptiles.

Studying Fossil Beetles

This fossil has pushed back the known existence of this type of beetle by about 60 million years.  Although this genus of soldier beetle is now extinct, the soldier beetle family is widespread with many thousands of species located in Europe, Asia, Africa and the Americas.

Soldier beetles can be found in many gardens, in the UK the best time to see them is July and August.  It is believed soldier beetles got their name as their bright shiny carapaces or elytra (wing cases) reminded early naturalists of the brightly coloured soldier’s uniforms that were worn at the time when the science of biology was beginning to develop in the western world.

Soldier Beetles in the UK

The common soldier beetle (Rhagonycha fulva), is ubiquitous within the United Kingdom.  It is easily identified thanks to its bright red colouring and the black tips to its rear.  This beetle, like many soldier beetles is an omnivore.  It can be found sitting on top of large flowers such as cow parsley and hogweed preying on small flying insects that visit the flowers and it also feeds on nectar.  They are rarely seen on their own but are often found with mates – hence their nickname “bonking beetles”.

The Same Chemical Defences

Many soldier beetles use chemical defences to protect themselves just like their Mesozoic ancestor.  Their wing cases are quite soft and offer little protection and if you are going to sit out on a big flower head all day in a brightly coloured uniform you are going to need some form of protection to stop you ending up as someone else’s lunch.

It seems this form of sophisticated defence mechanism has been around for a lot longer than scientists thought.  Not surprising really when you consider how long insects have been around, but it is interesting to speculate that this type of beetle with a predilection for sitting on flowers was around at the time when the first flowering plants were becoming established.  Did this family of beetles take advantage of the new angiosperms and as a result were able to thrive and diversify themselves?

Visit Everything Dinosaur’s award-winning website: Everything Dinosaur.

How the Dinosauria came to be Named

The classification of Dinosauria into a separate and distinct order is shrouded with controversy.  It may be widely known that the term “Dinosauria” was first used by Sir Richard Owen, how the term came into being and accepted by the scientific community is quite contentious.

Linking the Fossil Evidence

A number of attempts had been made link the three known ancient land dwelling reptiles – Iguanodon, Megalosaurus and Hylaesaurus in the early 1830s.  The distinguished German naturalist Hermann von Meyer (who was later to name and describe Plateosaurus in 1837), had used the phrase “Saurians” when describing these animals and their mammalian characteristics in a paper published in 1832.

However, it was a fossil unearthed in 1841 that finally provided the evidence to unite all these huge land reptiles into a separate taxon.  A new bone of an Iguanodon had been discovered on the Isle of  Wight.  This new discovery was brought to the attention of Richard Owen and he duly went off to the island to examine it.  The fossil was an Iguanodon’s sacrum (the lower part of the spine).  As Owen studied this new find it dawned on him that the Iguanodon sacrum had an identical characteristic to the sacrum of the Megalosaurus that had been on display at the Ashmolean museum, Oxford for the past twenty years or so.

Megalosaurus Fossil Material on Display

The Megalosaurus display case (Oxford Museum of Natural History). Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Five Sacral Vertebrae

The five sacral vertebrae forming the lower part of the spine of both the Iguanodon and Megalosaurus were fused in exactly the same way.  Having a fused sacrum strengthens the backbone and is an adaptation for living on land, dinosaurs have it as do mammals and humans (although our lower spines are fused in a different way to dinosaurs).  This fossil vertebrae provided the vital evidence of an anatomical link between the meat-eating Megalosaurus and the plant-eater Iguanodon.  They belonged to the same order.

Prior to this, these reptiles had been loosely grouped together under the term “Lacertians” but now these land animals were seen as a very distinct group from crocodiles, marine reptiles and pterosaurs.  They had characteristics very similar to mammals, with an upright gait, pillar like legs that were held directly underneath the body.

Richard Owen

Richard Owen had been engaged by the British Association for the Advancement of Science (BAAS) to produce a comprehensive paper on these ancient creatures – his “Report on British Fossil Reptiles”.  He delivered his paper in a presentation made at the annual meeting of the BAAS in August 1941, but extensively re-wrote it before its final publication in April 1842.  Working from his study at the Royal College of Surgeons in London, Richard added the following note to his paper:

“The combination of such characters, some as the sacral ones, altogether peculiar among Reptiles, others borrowed, as it were, from groups now distinct from each other, and all manifested by creatures far surpassing in size the largest of existing reptiles, will, it is presumed, be deemed sufficient ground for establishing a distinct tribe or sub-order of Saurian Reptiles for which I propose the name of Dinosauria”.

Richard Owen had toyed with a number of names for this new classification over the winter of 1841 but after discussing the matter with friends he hit upon the idea of using the Greek words “deinos” meaning terrible or fearfully great and “sauros”  meaning lizard.

The Classification of Dinosauria

Hence the term dinosaurs or terrible lizards came into being.

Perhaps Owen had been pointed in the direction of the Greek poetic style of Homer as the word “Deinos” is found in the work accredited to the ancient Greek poet.   In the prose, the word Deinos is used to mean inconceivable and unknowable, a very apt description; as few scientists could fail to recognise the impact of the establishment of a extinct sub-order of reptiles on the prevailing view about the Creation.

Mystery Surrounds the Naming of the Order

Mystery surrounds the naming of this order, much of the earlier work of Mantell is discredited in Owen’s paper.  Indeed he takes credit for many of the insights made by Mantell and others.  Poor Mantell is ridiculed for his inaccurate estimates of the size of Iguanodon.  Owen takes great delight in belittling Mantell’s comparisons of the fossils of Iguanodon with a modern Iguana.  He almost gleefully, mocks Mantell for naming Iguanodon from the fossil teeth resembling that of an Iguana lizard.

Owen states that the teeth when studied in cross-section under a microscope bare little similarity.  This is a little unfair, as at the time Mantell made his conclusions fewer Iguanodon fossils were known and he did not have access to a microscope.

Mantell and the Classification of Dinosauria

Ironically, it was Gideon Mantell who first pointed out the bipedal stance of Iguanodon.  He had noted a number of characteristics regarding the limb bones of Iguanodon that led him to conclude that this animal was capable of standing on its hind feet using its forelimbs for grasping vegetation.  Owen completely failed to notice this despite having better access to fossil specimens of Iguanodon than Mantell.  Owen envisaged Iguanodon as an elephantine type quadruped whereas it was Mantell who had given us the first insight into the true nature of anatomy of dinosaurs.

Dinosaur Models: Dinosaur and Prehistoric Animal Models.