Dinosaur Island

Femur of Iguanadon, vertebrae of stegosaurus, jaw of diplodocus...The Isle of Wight is sometimes called 'Dinosaur Island' and a tour around the dinosaur museum which is stuffed full of locally-found fossils shows you why.


The display is enthusiastic, rather than professional - with models, maps, and... dung






and lots of fossil molluscs (or ammonites) which I believe are the snails' close cousins.


Both types of animals died alongside each other in the great mass extinction that occurred 65 million years ago at the end of the Cretaceous. 'Mass extinction' - I remember hearing the term at university - it seemed alarming and oddly thrilling at the same time. Another name for it is the K/T boundary. 50 % of all lifeforms was wiped out. And there hasn't been just one mass extinction, but several - one at the end of the Cambrian, another at the end of the Ordivician and another really bad one, the worst at the end of the Triassic. During each one the conservative animals tended to survive, our lecturer told us - the ones that hadn't evolved very much and stayed exactly as they had been for millions of years. As Hodmandod Senior maintains - laziness always wins out in the end.

According to Wilkipedia the latest theory is that a comet, such as the Schumaker-Levi comet that hit Jupiter a few years ago, was a possible cause. The comet fragmented as it entered the atmosphere and hit the earth in several different places. This may have caused a large amount of volcanic activity in India known as the Deccan Traps and a lot of dust. This would have blocked out the light of the sun and caused the earth to cool - affecting especially those animals dependent on photosynthesising plants. Since the mammals of this time ate mainly dying and decayed food they survived, but the dinosaurs and ammonites did not. These animals had evolved into many different sorts - just looking at the ammonites found in the Ilse of Wight shows the variety at the end of the Cretaceous. Some of these were huge, some were unfurled, some were coiled into a sort of helix like modern day snails. They had become specialised, able to live in only certain conditions, so when the conditions changed they died out.


We wondered around the museum for an hour. It was a fairly primitive structure - a great metal-rooved barn packed with display cabinets and notices, and on the ceiling a model of an archopteryx flapped languidly like an over-large seagull.

When it was almost closing time we encountered the curator - easily identifiable with a small ammonite hanging on a a chain round his neck. I asked him which fossil he was most proud of finding and he showed us a piece of flint with a tiny shark's tooth embedded on one side. Apparently this small object could change how geologists believe flint is formed. Up until now flint is thought to have been formed by a great liquefaction of marine organisms seeping into the existing rock and solidifying. It replaced what was there already with stone, but the tooth embedded in this flint is stilll a tooth - the original material. It is still waiting to be examined by professionals and if it is found to be what the curator thinks it is it will cause a small geological revolution.

We had an interesting chat, but the most exciting thing we discovered was out on the beach. I had read about the dinosaur footprint and the curator told us exactly where and when to go. The tide had to be out so that the wave-cut platform at Hanover Point was exposed. It was slippery, covered in green weed and slimy mud, but we got there. The place was easy to find because next to it a square-shaped piece of rock containing another print has been carefully cut away.


Here is dinosaur's three-toed print and my hoof beside it. I like the idea of the two feet standing in the same spot 65 million years apart.

Then, as we turned back to shore we saw the remains of the petrified forest. As the temperature dropped all those millions of years ago the trees died too. They toppled into the rivers, floated downstream and the resulting log-jam is preserved here.

It was the end of the Cretaceous and the forming of the white cliffs, but the start of the history of the Isle of Wight so I thought I'd write about that first.