Fossil Finder Database 2022
Corals are quite rare in chalk. These are solitary corals that grew as individual, self-contained animals attached to the sea floor. Chalk formed from a soft ooze of microscopic plants and therefore the sea bed was not often hard enough for corals to attach too.
Designed for life Because sharks are perfectly designed for hunting in the sea, they have evolved little since their first appearance over 200 million years ago. They are not bony, so usually only their teeth are fossilised.
Sponge bed Most sponges live in the sea, fixed in one position throughout their adulthood. They filter the water for food, so prefer water with a current. Some Inferior Oolite beds are crowded with sponges. This form of sponge grew in concentric shapes.
In many parts of the UK, the rock of the ‘Corallian Group’ is rich with fossil corals. But that isn’t the case in Dorset. Only the Ringstead Coral Bed contains corals in significant numbers. That is because, for most of the time during which the Corallian rocks were forming, the environments in what we now…
The sponge texture is very clear on this specimen. Many sponges are only partially-preserved, but the texture of the body and circular, or radial symmetry, can be quite distinctive.
Fine detail Sponges are often preserved in flint. The flint comes from silica that originated in the tiny needles or ‘spicules’ that other sponges used to build their bodies. The needles were scattered and buried in the sediment and then later dissolved away by ground water percolating down through the chalk. Later still that silica…
Mega-footprint! This print was probably made by the hind legs of a megalosaur, a type of large, meat-eating dinosaur. It walked on two powerful legs, with three-toed feet – as you can see from the footprint. The megalosaur was equipped with big, sharp, serrated teeth, which it used to rip apart its prey, including the huge plant-eating sauropod dinosaurs.
Tubeworms protect themselves by secreting a hard tube around their bodies. The tube is made of a tough substance called chitin (the same substance that makes up the shells of lobsters and crabs).
The sponge texture is very clear on this specimen. Many sponges are only partially-preserved, but the texture of the body can be quite distinctive.