Ancient winged Insect left Impression in Carboniferous Mud

The western part of the United States may have a higher profile than the eastern part of the USA when it comes to fossils, this may be due to the large number of dinosaur fossils found in states such as Utah and Montana, but the east of the USA can produce some amazing fossil finds as well, such as a spectacular insect fossil.

Spectacular Insect Fossil

Careful research combined with a little luck has helped fossil hunter Richard Knecht find an amazing fossil of a flying insect near Emerald Square in Massachusetts.  Locked away for over 310 million years, the oldest known imprint of an insect, a trace fossil,  has been found, whilst Richard was lost.

The three-inch-long Arthropod, which scientists believe may be a distant relative of the modern mayfly, apparently made its mark by briefly landing on a pool of soft mud over 310 million years ago, the trace fossil has preserved the moment it landed and rested on the soft, sticky ground.  The fossil is so well preserved that individual body segments of the long abdomen can be seen and the imprints made by the insect’s six legs are clearly visible.

A Rare Find

Knecht and his professor, palaeontologist Jacob Brenner of Tufts University, are hoping that this rare find, along with the subsequent discovery of a fossilised wing at the site last week, will yield new insights into insect behaviour at a time when such creatures dominated life in the air.

“The level of detail is really unseen in continental deposits,” commented professor Brenner. “It’s unusual to see a flying insect make such a deep impression in this muddy sediment . . . and we don’t have many good body fossils from this time period with these early flying insects.”

Photographs may look a little indistinct but if you look carefully the impression of the dragonfly-like creature can be seen.  The head of the animal is facing to the right of the picture and the six impressions either side of the long, stick-like structure are the legs , behind the last pair of legs the abdomen can clearly be seen.

Wings Not Preserved

The wings are not preserved as they did not touch the mud when the creature landed.  The legs look quite stubby, but only part of them was preserved.  This is a trace fossil, a fossil that shows evidence of the activity of an organism, such as their tracks, trails, burrows or borings.

This is a truly remarkable discovery, it is very rare for delicate creatures like insects to become fossilised in rock, if they do the fossils that are preserved are usually fragmentary in nature, compressed, distorted and subsequently difficult to interpret.

Talking about his find Richard said:

“It’s not squished. It’s not deformed. We don’t have to try to piece it back together. We can see it as it was, and we get the behaviour,”.

Richard Knecht and professor Brenner went hunting in that area because research they had carried out enabled them to uncover a 1929 thesis that indicated that fossils may be found in the strata of the region.   New England isn’t a particularly rich source of prehistoric remains.

This really is a lucky find, firstly because these types of impressions were not made very often and the chances of one being preserved is extremely remote.  In addition, Richard has been trying to find another site and got lost, simply finding this fossil location by accident.

As Richard wandered around trying to get his bearings, at one rock outcrop, he gripped a broken edge, it came off in his hand, revealing the insect fossil.  The outer part of the rock was already split and had it been exposed to the cold of a New England winter, ice and frost action may have damaged this fossil, perhaps destroying if forever.

It really was a lucky find.

Increased levels of oxygen in the Carboniferous enabled arthropods to grown to huge sizes, many times bigger than their modern counterparts.  According to some researchers, atmospheric oxygen may have been as high as 30%.  To stay in the air, flying insects need to burn up a lot of oxygen in their muscles, the maximum size of a flying insect is governed by the extent to which oxygen can reach the tissues in the animal that require oxygen.

A higher level of oxygen in the atmosphere would have helped increase the efficiency of the insect’s metabolism and allowed them to evolve into larger sizes.  At the time, no other creatures flew; (pterosaurs for example did not come along until the Triassic), so insects such as the one found by Richard Knecht would have dominated the air.

Everything Dinosaur stocks a range of invertebrate prehistoric animal models, replicas of iconic creatures from the fossil record: Replicas of Iconic Animals from the Fossil Record.

New Study Sheds Light on the Bite Force and Gape of Smilodon spp.

The large, sabre-like teeth of Smilodon (Sabre-toothed Cat) were too fragile and likely to be damaged if this member of the Machairodontinae bit down onto bone.  How the large canines of these predators were used, has been the subject of considerable debate.  Some scientists have even suggested that the sabre-teeth were highly ornamental and only used for display, perhaps to intimidate other members of the pride and to establish a social hierarchy.  It had been argued that the row of forward pointing incisors in the upper jaw were the main killing teeth and these teeth were also the most effective at stripping meat from any kills.

An Illustration of Smilodon (Sabre-Tooth Cat)

Picture credit: Everything Dinosaur

What has been established, is that Smilodon was able to open its jaws far wider than any species of extant Felidae.  The wide gape was an adaptation to having over-sized teeth in the jaws.  But how strong a bite and indeed, how the jaw muscles evolved to permit such a gape have been the subject of a new study, the results of which have been published in this month’s edition of the Zoological Journal of the Linnean Society.

The new analysis, carried out by scientists from Aalborg University (Denmark), reveals that the Smilodon’s jaw muscles evolved into a specialised pattern, which allowed them to open their mouths so wide.  The study was led by Dr Per Christiansen, who used a complex model to assess how the muscles in the jaws evolved.

Pictures show a modern big cat’s jaws on the left with the lower jaw opened as wide as it can be without damage to the jaw and the jaw muscles.  This is compared in the picture above to the jaws of an extinct Smilodon spp.  The jaws of Smilodon can be opened to a much wider angle than a jaws of a modern extant big cat.

Smilodon

His model revealed how the cat’s jaw muscles were aligned to pull its jaws closed, very directly and efficiently.  But Smilodon would also have done something that every cat-owner can see a relic of in their own pet.

Dr Christiansen explained:

“When you put a piece of food on the floor for your cat, you’ll see it bobs its head forward as it eats it.  And we know that [Smilodon] probably closed its jaws by twisting its head downward and throwing its head forward.  Its neck was longer than that of modern cats and its neck muscles would have been stronger.”

The study also examined the earliest and most primitive members of the Machairodontinae, although Dr Christiansen did state that Smilodon in particular was “outrageous in terms of its anatomy”.

He went onto add that Smilodon:

“Was the most [highly evolved and therefore] different from modern cats, so to understand this animal from a biological sense, you need to study more primitive animals to work out why they have become that way through evolution.”

He examined hundreds of skulls, drawing an evolutionary map showing why Sabre-tooths evolved such different jaw anatomy from modern cats.

Dr Christiansen explained that what he termed “killing ecology”, was the driving factor, the evolutionary pressure to kill prey with a deep and efficient stab to the throat.

He stated:

“The cat species became gradually more and more specialised, culminating with monsters such as Smilodon.”

Longer Canine Teeth

As Sabre-toothed cats evolved longer canine teeth, their jaw muscles actually grew smaller, but the fibres became more vertically orientated and thus probably more efficient in closing the jaw.

Dr Christiansen explained:

“At the same time, changes in the way the muscle fibres inserted on the lower jaw meant that the animals could stretch their muscles more – the fibres became re-orientated so as to allow a higher gape, necessary for gaping with huge fangs.”

A Model of a Smilodon (S. populator)

The Rebor Smilodon populator Stray Cat 1/11th scale model shown in close-up view. This is the “plain” colour variant and it has the mouth-closed head attachment. The model is shown in lateral view. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

However, as specialist carnivores, dependent on large, relatively slow moving prey that they could ambush, this could have been the reason for their demise whilst other members of the Felidae such as leopards, tigers and lions are the apex predators in their environments today.

Everything Dinosaur stocks a wide range of Smilodon models and figures: Models of Prehistoric Mammals.

Portuguese Builder hopes to Cash In on his Lucky Find

With increasing prices being paid for dinosaur fossils and other artifacts from the past, sometimes scientific research can be thwarted by an entrepreneur out to make a quick profit.  A dinosaur tail is up for sale.

One such scenario is currently being played out in Portugal, where the owner of a construction company has put his dinosaur discovery up for sale to the highest bidder.

Gonsalo Ribeiro, the finder of the dinosaur fossils, believed to be an articulated sauropod tail that dates from the Late Jurassic, has put this rare find up for sale on the internet.  Commenting on his discovery, Mr Ribeiro stated:

“I own an excavation business, and one day when we were out digging, we came across some stones, but when I looked closer, I noticed that they were not stones”.

Dinosaur Tail up for Sale

Ever since the most complete Tyrannosaurus rex skeleton found to date was auctioned by Sotheby’s in 1997, dinosaur fossils up for sale have hit the headlines and prices have rocketed.  That particular fossil was the famous “Sue” T. rex discovered in August 1990 by Susan Hendrickson, it was auctioned on October 27th 1997 and fetched $8.36 million.

A number of other widely publicised auctions of ancient prehistoric animal remains have taken place, there are major sales at least once a year.  Some of these sale items are purchased by the public purse or by philanthropists who later donate these items to museums.  This enables scientists to carry out research on them, but many are bought  by private collectors and they are then no longer available for study.

To read about a marine reptile fossil being auctioned: Fancy a Mosasaur for Christmas? Prehistoric animals under the hammer.

Recently, an almost complete Triceratops skeleton was sold (T. horridus), although the reserve price of 500,000 Euros at the original auction was not met, it did eventually sell for nearly 600,000 Euros a few days later.

Triceratops article: Triceratops for Sale.

The advertisement for this particular fossil sale reads: “For sale, dinosaur spine 90 per cent intact”.  It sounds to us like these are elements of the caudal vertebrae, perhaps those located immediately posterior to the sacral vertebrae, (the tail bones immediately behind the hips).

The tail section is estimated to be 3.6 metres long and has been dated between 152 and 146 million years (Kimmeridgian to Tithonian faunal stages).

When asked to comment on the auction, leading Portuguese palaeontologist Dr Octávio Mateus of the Museum of the Lourinhã stated that this particular find was of “huge scientific value”.

Mr Ribeiro has refused to hand over his treasure to a museum, claiming “the figures they offer are far off the mark.” A bold statement as setting a monetary value on such an item is a very difficult business.  It is believed that he has already turned down an offer of 100,000 euros (£84,000).

An Opportunity to Make Some Money

For Mr Ribeiro, this may be an opportunity to make some money, perhaps a lot of money, but this is really a sordid business as his actions are denying scientists the opportunity to study precious Late Jurassic sauropod material and eventually such a set of fossils could be put on public display at a museum for everyone in the community to see.

Dr Mateus, a specialist in the Jurassic dinosaurs of Portugal having worked on a number of specimens including the brachiosaurid Lusotitan that he helped name and describe in 2003,  has published a note on the website denouncing what he called the “sale of our heritage as if it were a car or a pair of shoes”.

Palaeontologists are calling for legislation to help protect fossils so that they can be declared “public heritage” and protected from being sold to the highest, wealthiest bidder to the detriment of the scientific community and the public.

Such instances are likely to become more and more common as internet sites and specialist auction companies provide a ready market for such valuable items.  We wish Dr Mateus and his colleagues well and hope their case is given a fair hearing by the Portuguese legislature.

Everything Dinosaur offers affordable dinosaur and prehistoric animal models.  There is no need to upset the scientific community, take a look at the models section of the Everything Dinosaur website: Dinosaur and Prehistoric Animal Figures.

Single Celled Giant – Responsible for Ancient Trace Fossils?

One of the most momentous events in the history of life on our planet took place around 545 million years ago, at a time when the Earth looked very different than today.  For a start it was spinning faster on its axis, meaning that our 24-hour orbit was something unimaginable back then, days would have lasted something like 20 hours.  The atmosphere would have been completely alien to us, in fact had a human being been able to travel back in time to the Cambrian, they would have needed to bring breathing apparatus as the air with its lack of oxygen would have been quite toxic to us.

Cambrian Trace Fossils

The continents with which we are so familiar today, would have been unrecognisable, in the western hemisphere; the fragmented parts of a super continent were being pulled apart by an ocean ridge, in the east, another, larger remnant of this huge landmass stretched almost pole to pole.  Most of the United Kingdom lay off the coast of Gondwana, the name given to the area of land in the eastern hemisphere, although rock that is found in Scotland today was actually thousands of miles away in the western hemisphere.    The geological period we now know as the Cambrian was first defined in 1835 by an English professor of geology – Adam Sedgewick.  He mapped rock strata in Wales and showed that it was formed after older Precambrian rocks but before the rocks believed to have been formed in the Silurian period.

As our understanding of geology has improved, these Welsh rocks are not used anymore to delineate the start of the Cambrian, strata in Newfoundland are regarded as indicative and distinctive enough to be seen as forming the boundary between the Precambrian and the Cambrian.  The starting point of the Cambrian is marked by the appearance of trace and body fossils, indicating diverse animal life.  Trace fossils are preserved evidence of activity, for example a fossil cast of a worm burrow or a trail left in soft mud on the ocean floor that has become preserved.

During the Cambrian, there was a rapid acceleration in evolution and a vast array of new creatures suddenly appear in the fossil record.  Animals with hard parts such as shells and external skeletons evolved and this phenomenon has been termed the “Cambrian Explosion”.  Prior to the evolution of hard parts that have a higher potential for fossilisation, only a very few types of fossil were known – many of which were trace fossils, such as tracks preserved in mud as a creature crawled over the seabed.  The first trilobites appear, amazing arthropods, distant ancestors of spiders, mite, insects and crustaceans.  trilobites are one of the “star turns” in the fossil record.  These marine creatures evolved into at least nine Orders and survived right through the Palaeozoic, with the very last of their kind becoming extinct at the end of the Permian approximately 250 million years ago.

An Illustration of a Typical Trilobite

Illustration credit: Everything Dinosaur

To view a model of a trilobite – from Everything Dinosaur’s fossil replica series:-

Model trilobite and other prehistoric anmals: Prehistoric Animal Models.

Up until now, the trace fossils, many of which are preserved trackways, are believed to have been made by complex, soft-bodied organisms, perhaps ancestors of the armoured trilobite.  This has been an appropriate assumption as; in a relatively short period of geological time, the Cambrian explosion occurs and a myriad of life forms are recorded as fossils.  It had been widely accepted by palaeontologists and ichnologists that trace fossils such as these trackways were made by soft bodied, complex, bio-symmetrical organisms, a fair assumption, since just a few million years later a great diversity of complex life occurred and these animals must have had complex ancestors and life would have been abundant.  Being soft-bodied there is little fossil evidence to be found, the fossils were thought to be disproportional to the amount of life forms that had already evolved.

However, new insight into the habits and lifestyle of a very ancient creature has cast doubt on this assumption, it appears that single-celled, very simple organisms are capable of leaving tracks in soft mud and it could be these life forms, not more complex ones that left the Early Cambrian and Precambrian tracks in mud that became trace fossils.

New Research

New research into a little known, distant relative of microscopic amoebas called Gromia sphaerica has proved that these little organisms travel across the sea floor and as they do, they leave trackways behind.  These tracks are very similar to the fossilised tracks found in Precambrian rocks.  It has been suggested that the Precambrian trace fossils may not be evidence of complex organisms but the preserved trails of an ancient type of Gromia.

If this is the case, then the Cambrian explosion becomes even more of a mystery, as what evidence we have of complex organisms in Precambrian strata may be reduced if some of these tracks are attributed to types of single-celled organism.

G. sphaerica was believed to be sessile and of a epifaunal habit (living on the sea floor, either on soft sediment or attached to rocks, but not moving).  Observations from the bottom of the Arabian Sea indicated this.  However, a group of researchers have located a colony of the coast of the Bahamas and these creatures are vagrants (move over the sea floor), leaving trails up to half-a-metre in length.

Gromia sphaerica is gigantic for a single-cell eukaryote (cell enclosed by a membrane), some specimens have been measured with diameters in excess of 30 mm, about the size of a large marble.  These creatures were recorded wandering across the seabed by Mikhail Matz of the University of Texas at Austin and a group of fellow researchers

A distant relative of amoebas, these strange organisms have left trails in the Caribbean seabed that resemble the trace fossils found in Precambrian rocks.

The red arrow in the picture is pointing to a trail left by a Gromia sphaerica.  The round lump is the organism itself, covered in a light coating of sediment.  The trail consists of two small ridges on the outside, and one thin bump running down the middle.  This pattern is consistent with certain trace fossils.  Scientists are confident that prior to the Cambrian, life forms were exploiting the surface layers of marine sediments, now this new evidence may indicate that multi-celled, bio-symmetrical organisms were not as abundant as the fossil record indicates, if some of these trace fossils can be attributed to the ancestors of Gromia sphaerica.

Commenting on the research, Matz stated:

“If these guys were alive 600 million years ago, and their traces got fossilised, a palaeontologist who had never seen this thing would not have a shade of doubt attributing this kind of trace to the activity of a big, multicellular, bilaterally symmetrical animal”.

“This is a very important discovery,” Shuhai Xiao of Virginia Polytechnic Institute added. “The fact that protists can make traces has important implications for how we interpret many trace fossils.”

This research could have dramatic implications for the Cambrian Explosion, if single-celled organisms were making some of the trackways, complex animals were not as abundant as previously thought.   To quote the researcher Matz, every type of animal phyla around today “suddenly burst out of a magic box.  It wasn’t a gradual development”.

In addition, genetic analysis of the water-filled cells of G. sphaerica reveal tantalising evidence that it could be one of the oldest type of organism on the planet – a living fossil.

“There’s a 1.8 billion year old fossil from the Stirling Formation in Australia that looks just like one of their traces, and with a discoidal body impression similar to these guys [G. sphaerica]“.  Matz commented.

“We have not proved anything, but we might be looking at the ultimate living macroscopic fossil”.

The Stirling Formation in south-western Australia is famous for its fossils of Precambrian life, many types of soft-bodied animal are preserved in what was a shallow, tidal, sandy sea bottom.  Sharing this ancient world, a part of the geological time scale called the Cryptozoic (time of invisible life due to the paucity of the fossil record), were jellyfish.

Jellyfish are another example of a living fossil, this type of animal may have swam in prehistoric seas, as much as one billion years ago.

To read a related article on jellyfish and life before the Cambrian explosion:

Jellyfish – an example of a living fossil.

Everything Dinosaur supplies a model of a Medusa type jellyfish, part of a set of fossil animal replicas that include belemnites and ammonites.