Rebbachisaur Cervical Vertebra – Collected by Kai Bailey and painstakingly cleaned and restored by Fossil Preparator Gary Blackwell.
Calcite-rich permineralised dinosaur bone, from a red mudstone bed of the Wessex Formation approximately 125 million years old. Now on display at the Dinosaur Expeditions Centre at the Dinosaur Farm, Isle of Wight.
In 2010 a local fossil collector Kai Bailey discovered some Polacanthus bones. A section of the sacral shield, an ilium (hip bone) a sacral (hip) vertebra and some scutes (bone armour in the skin). Later he discovered a large spike and a large lump of bone. In 2013 he approached Dinosaur Expeditions C.I.C. and generously offered to loan us this Polacanthus material to go on display at the newly created Dinosaur Expeditions Centre. Needless to say I was ‘over-the-moon’ about having Polacanthus material in close accessible proximity and couldn’t get the loan form signed quick enough!
We placed the material in one of the largest display cabinets which formed a core part of our Isle of Wight Dinosaur bone exhibition. The cabinet was directly opposite our diorama of the Wealden floodplain; a representation of the environment in the Lower Cretaceous with a large painting produced for us by internationally renowned palaeoartist John Sibbick. The landscape was a work-in-progress with vegetation but no dinosaurs. Several suggestions had been made but as a start-up Community Interest Company we couldn’t afford to commission a model or purchase a fibreglass dinosaur.
We searched the internet and discovered Jolly Roger Limited, a UK based supplier of Fibreglass models. After browsing their website several possibilities presented themselves. None of them would be ideal representations of local dinosaurs without some modification. Given our experience in building a ‘Barn sized Sauropod skeleton’ this additional work shouldn’t present a barrier to getting the result we wanted.
Within a couple of months of operating we had saved enough to purchase a single dinosaur and have it shipped before the Summer Holidays began. After careful consideration the Directors decided that the Minmi model seemed to be the best option with a small crocodile added for good measure. The Minmi looked good in its original condition and would require less work to complete the transformation into a Polacanthus than turning a Utahraptor into an Eotyrannus!
A couple of weeks later we were in possession of a Minmi model which seemed almost made to measure when we mounted it on the Wealden floodplain diorama, just in time for the Summer Holidays.
Royal Mail Stamp: Polacathus by John Sibbick
Introduction:
I have to confess I really like Polacanthus foxi. My infatuation started 20 years ago. I was a teenage volunteer at the Dinosaur Farm and in the intoxicating vapours from acetone (used to clean and repair the ‘Barnes High Sauropod’) on a warm sunny day, the volunteers were all deep in conversation about our favourite dinosaurs.
Now our ‘local’ dinosaurs weren’t the household names of A-list celebrity dinosaurs that trip off the tongue; T.rex, Triceratops, Stegosaurus, Diplodocus and even Velociraptor (newly elevated to cult status due to the success of the Jurassic Park movie). We had the old school dinosaurs of Iguanodon, Hypsilophodon, and Polacanthus and predators including a Theropod referred to as Megalosaurus (but identified as Neovenator in 1996), the fish-eating Baryonyx, and Aristosuchus, Calamosaurus, Calamospondylus, Ornithodesmus (later identified as the Pterosaur Istiodactylus in 2001) and Thecocoelurus (a number of assorted small Theropods known from a hand full of bones).
I honestly didn’t have a favourite. Sure I could repeat the well trod names of famous Theropods but I didn’t have an emotional response to these dinosaurs other than the ‘coolness’ associated with them. As wannabe palaeontologists we talked about what we wanted to specialise in when we ‘qualified’ with all the naivety that comes with [Imagination + Wishful Thinking = Talking Nonsense]. It seemed that everyone wanted to research Theropods. I realised that if I was going to become a Palaeontologist I would need to broaden my interest as very few Palaeontologists exclusively specialise in Theropods, there isn’t enough of them (never mind the lack of fossil bones due to their relative rarity) to go around!
So I thought about the options and in the end I realised that there wasn’t much interest in Polacanthus. It looked like a giant sheep with a shield over its hips, covered in spikes. It might not have the ‘coolness’ associated with Theropods, the sheer mass of a Sauropod or the relative abundance of the Ornithopods Iguanodon and Hypsilophodon but it held its own in the Wealden floodplain of the Lower Cretaceous 125 million years ago and deserved respect.
Over the next few years I had read everything written about it, visited the collections of Polacanthus material held in the bowels of the Natural History Museum in London (BMNH), the Museum of Isle of Wight Geology and even a privately owned specimen known as ‘Spike’. My infatuation was complete save for the fact I had never found a piece of Polacanthus on the beach.
With mild weather in mid-November we decided to conduct the second survey of the cliffs after recent rainfall.
The cliffs were boggy, with large slumps of soft mudflows, which made accessing sites difficult and in several cases impossible.
Several bones were found (not the small theropod we had hoped for) but from an unfortunate sea bird! Interesting from a modern taphonomy perspective though.
We were able to discover another four previously unknown sites mostly producing fresh water bivalves, more Hybodont shark spines and fusain preserved fossilised wood. Sadly no significant bone discoveries were made except for isolated fragments discovered on the flint gravel shingle below the high tide level of the beach.
This would be the last survey of the year with the next survey due in February 2015.
With the Dinosaur Expeditions Centre temporarily closed for renovations work, we took the opportunity to survey the cliffs between Cowleaze Chine and Barnes High (opposite the Dinosaur Farm).
Oliver was joined by volunteers Ashley and Paul. On previous solo fossil hunting expeditions Ashley discovered a rare theropod (meat-eating dinosaur) tibia (lower leg bone) and a decade earlier, Paul discovered a rare theropod dorsal vertebra (back bone). So if there was anything to be found there was a good chance we would be able to find it.
We made our way over Barnes High and searched high and low for three days. We identified nine sites and found Hybodont shark spines, fresh water pond mussel bivalves, fossil wood and several dinosaur bones.
The survey produced several highlights. Paul found a small Theropod (meat-eating dinosaur) phalange (toe bone), Ashley found part of a large unidentified sacral (hip) vertebra and Oliver found an isolated Anteophalmosuchus (Goniopholis) crocodile tooth!
