New Research Indicates the Glyptodonts were Classy Swingers

A Sabre-toothed cat on the prowl for an easy meal, might mistake the slow moving, ground hugging glyptodont for an easy target, after all, this armoured prehistoric mammal was hardly able to flee from such a predator.  However, as well as being covered in dermal body armour, strong enough to deter even the most ferocious bites, members of the Glyptodontidae had another means of defence, and a recent scientific study has provided an insight into just how effective this defence was.

Prehistoric Mammals

A number of glyptodont species have been named and described, many with elaborate tail spikes and clubs, some of which resemble medieval maces and other brutal weapons.  A new study, from a team of South American scientists indicates that these clumsy looking beasts were able to swing their tails and clubs with the precision of a Kevin Petersen off-drive or a Roger Federer back hand.

Physicist Dr Rudemar Ernesto Blanco and his colleagues from the Faculty of Science in Montevideo, Uruguay conducted experiments to assess the mechanical efficiency of the various tail clubs found on glyptodonts.  Their research, published in the scientific journal Proceedings of the Royal Society Biology, suggest that just like cricket bats and tennis racquets, the tails of glyptodonts had a “sweet spot” and this coincided with the positioning of the largest spike or part of the tail club.

This new study provides evidence that the glyptodonts were no push overs when it came to a prehistoric pecking order.  Their tail spikes and clubs were highly adapted to deliver accurate, powerful blows on any other creature brave enough to challenge them.  These tail clubs were not just used to fend of predators, but also used to settle disputes amongst rivals, perhaps fighting over mating rights.  A number of glyptodont fossils have been discovered with broken skulls, perhaps testimony to the power and accuracy of a rival’s tail club.

Hitting the “Sweet Spot”

Stars of the tennis circuit or cricket know the importance of hitting the ball with the correct part of the bat, proper use of such equipment can prevent wrist injuries and ensure a tennis ball is hit with more power or a cricket ball is thumped effortlessly to the boundary.  It seems that natural selection may have led to the evolution of “sweet spot” amongst glyptodonts.

A Scale Drawing of a Glyptodont (Glyptodon clavipes)

Picture credit: Everything Dinosaur

To see a scale model of a Glyptodon and other scale models of dinosaurs and prehistoric mammals, take a look at the CollectA Deluxe model range: CollectA Deluxe Prehistoric Life.

Dr Blanco and his team were inspired by previous studies into the mechanics of tennis racquets and baseball bats to try to engineer a better designed instrument for the sports person to use.  A large, “sweet spot” or “centre of percussion” provides a considerable advantage.  The glyptodonts originated in South America, perhaps the absence of large mammalian predators allowed this particular family from the order Xenarthra to grow large and evolve into many numerous forms.  The fossil record shows that glyptodonts migrated into North America when the land bridge connecting South America to the northern part of the Americas was formed.  Indeed, one member of the Xenarthra is still spreading northwards to this day – the armadillo.

Dr Blanco commented:

“We found in several of the large species the centre of percussion was almost at the same position of the largest spike in the tail.  These spikes were probably useful to increase the damage during a tail blow like those in the middle age spiked mace”.

Studies of smaller species of glyptodonts carried out by the South American team indicate that smaller animals used their tail clubs in slightly different ways when compared to the larger species.  These animals probably used their tail clubs in more varied ways with less power and precision.

Asked to comment on this aspect of their research Dr Blanco stated:

“We concluded several large species of glyptodonts used the tail clubs mainly for powerful blows in ritualised fighting but the small species used the tail clubs also in other situations as defence against predators”.

It seems that many of these larger species of glyptodonts (some were up to 3 metres long), were very capable of wielding their tail clubs with devastating effect.  Perhaps the hungry Smilodon had better look elsewhere for a meal.

We at Everything Dinosaur have our very own “sweet spot” for the glyptodonts.  As a fossil group, their significance cannot be doubted after all, Charles Darwin studied them and the Glyptodon name (means grooved or carved tooth) was first used by Sir Richard Owen.  Glyptodonts are often included in Ice Age mammal box sets, although they were more associated with inter-glacial periods and warmer climates than the Northern Hemisphere mammal models that normally accompany them in these box sets.

Glyptodonts

We especially like the Glyptodon mother and baby soft toys.  It is hard to imagine these cute creatures wanting to hurt anyone.

Glyptodon Mother and Baby

Prehistoric Mammal (Glyptodont Soft Toys).

Picture credit: Everything Dinosaur

To view the range of prehistoric plush and dinosaur stuffed toys available from Everything Dinosaur: Dinosaur and Prehistoric Animal Soft Toys.

Ancient Cephalopod Ink Sac – Provides Ink for Self Portrait

Although the solid piece of a belemnite’s skeleton (the guard) is a common find on the beaches of Charmouth and Lyme Regis (Dorset, England), finding the preserved soft body tissues of any cephalopod is an extremely rare event.  However, such is the state of preservation at one fossil site in Wiltshire, that not only have soft tissues been preserved but scientists have been able to reconstitute the ink from the squid-like creature’s ink sac and then write and draw with it.

Prehistoric Ink

The fossil in question is a belemnite, the scientists who made the discovery commented that the chances of finding such an exquisitely well preserved belemnite specimen, one that had soft parts including an ink sac still preserved as “a billion to one chance”.

Many scientists talk about a discovery re-writing the fossil record, but in this instance the researchers were able to liquefy the ink contained in the preserved remains of a 155-million-year-old creature and draw the animal as it would have looked in life and even sign its Latin name Belemnotheutis antiquus under this unusual self portrait.

The word “belemnite” comes from the ancient Greek for a dart.  The internal skeleton or guard (made from tough, resistant calcite),  is a very common find, particularly at the famous “belemnite beds” on the Charmouth side of the Lyme Regis bay area.

An Illustration of a Belemnite

Picture credit: Everything Dinosaur

The specimen that yielded the ink for the self portrait came from a site near Christian Malford in Wiltshire.  This location had been originally discovered by engineers building the Great Western Railway in the 19th Century but the directions to it were lost and a team of researchers from the British Geological Survey set out to see if they could re-locate it.  This is a case of real fossil detective work.  They had some original notes to go on, plus the fact that the fossil site had to be found somewhere along the Wiltshire stretch of the old Great Western Railway.

Fortunately, the team were able to rediscover this special site, and some of their subsequent excavations were filmed as part of the BBC/Open University series “The Fossil Detectives”.  The site when it was discovered in the early 1840s, was quickly recognised as being of very great importance.  A number of leading scientists in the embryonic study of palaeontology wrote papers on the specimens found at the site, including Sir Richard Owen and Gideon Mantell.

Some Fossilised Belemnite Guards (Dorset)

Picture credit: Everything Dinosaur

The pound coin provides a scale for these various pieces of fossil belemnite guard found in just a few minutes whilst searching the high water mark at Charmouth beach.

Belemnites Related to Extant Squid

Belemnites resembled squids and they probably fulfilled the same role in the marine food chain as many squid species do today. They had ten arms of equal length and each arm had as series of between 30-50 curved hooks that helped them to grasp prey and manipulate it towards their beak-shaped mouths.

Many fossils of the marine reptiles known as ichthyosaurs have belemnite hooks preserved in the area where the stomach would have been. This indicates that many of these marine predators preyed on belemnites and that they were an important food source.  Scientists have estimated that although the origins of the belemnite family can be traced back to the Palaeozoic it was during the Mesozoic that this group rapidly diversified and expanded.  An estimated 2,000 species of belemnite are known in the fossil record.  Despite being hugely successful in marine environments, no trace of belemnite fossils have ever been found in strata derived from a freshwater environment.  It seems that belemnites were entirely marine and nektonic (swimming actively).

To view a model of a belemnite and dinosaur toys we recommend that you take a look at the CollectA Prehistoric Life model range: CollectA Age of Dinosaurs Prehistoric Life Models.

Fossils of cephalopods with soft tissue elements preserved are extremely rare.  Pictures show a superbly preserved specimen of a Belemnotheutis spp.  The animal is facing towards the right and some of the hooks associated with the tentacles can be seen in the top right corner of the picture.  Belemnites probably swam backwards by projecting a jet of water through a syphon-like structure that was positioned under the front of their bodies.

We think the pictures shown, represents a Belemnotheutis spp. from the famous Solnhofen limestone deposits in Germany.

The British Geological Survey team removed a total of 240 tonnes of rock in the ten days or so they had to explore the site.  A number of extremely well preserved invertebrate fossils were found, including one of the squid-like animal that was able to yield ink from its fossilised remains.  The dark, stained area of the fossil was carefully treated with an ammonia solution which permitted the ink to be liquefied and used for the illustration.

Amazing Preservation

The amazing preservation was the result of what palaeontologists call the “Medusa effect”.  Fossilisation occurs very quickly, permineralisation is rapid and soft body parts are fossilised as well.  The soft tissue becomes mineralised with phosphatic elements and even eyes and delicate tentacles are captured by this very rare process.

Commenting on the re-discovery of the Victorian fossil site, Dr Phil Wilby of the British Geological Survey stated:

“It’s among the world’s best fossil preservation.  It’s a squid-like creature, but it’s not like anything we have in the world today.   You really don’t imagine anything so soft could be so well preserved three dimensionally.  It still looks as if it is modern squid ink.  It’s absolutely incredible to find something like this.  We felt that drawing the animal with it would be the ultimate self-portrait”.

Dr Wilby can be seen in photographs proudly showing off the drawing of the ancient marine animal.  When asked whether other drawings would be made using the prehistoric ink, Dr Wilby stated that this material was so valuable that it would be very unlikely that more drawings would be made.  Part of the remaining ink sac and ink has already been despatched to Yale University in Connecticut (United States) for further, more detailed analysis.

The British Geological Survey team remain unsure as to why conditions arose at the bottom of the sea at this precise location 155 million years ago that permitted such exquisite preservation of organic remains.

A Replica of a Belemnite (CollectA Age of Dinosaurs Popular Belemnite Model)

CollectA Age of Dinosaurs Popular Size Belemnite model.

To view the CollectA Belemnite model (whilst stocks last) and other replicas of iconic fossil animals: Everything Dinosaur Learning Materials (Fossil Replicas).

Dr Wilby stated:

“About 155 million years ago, millions of these animals were dying in this precise area.  We don’t know why that is.  In normal circumstances, the decomposition process means only the hard parts of animal are preserved, such as the bones, shell and teeth.  The odds of this find are easily a billion to one and probably much greater”.

Such fossils can tell scientists much more about these strange, squid-like creatures than the rostrum or phragmocone remains.  The fossilised soft tissue once studied will enable scientists to discover whether this particular belemnite was a fast or slow swimmer by analysing the structure of the preserved muscle fibre impressions.

More than twenty of these very special fossils have been removed from the site and added to the British Geological Survey collection at Nottingham.  It is hoped that over the next few months more data on these extinct creatures will be obtained as the fossils are prepared and studied under laboratory conditions.

One thing is for sure, a belemnite has literally managed to write its name in the fossil record.