Fossils - the history of life

Fossils are the preserved remains or traces of prehistoric animals and plants found in sedimentary rocks. A fossil could be a bone, a shell or leaf but it could also be a footprint or burrow. In fact, any preserved evidence of the activity of prehistoric life on the planet could be considered a fossil. There is no clear definition of how old something has to be to be classified as a fossil but it's fair to say that anything older than 1 million years is a safe bet.

The fossils of the Jurassic Coast come from rocks that formed between 250 and 65 million years ago. This part of Earths history is known as the Mesozoic Era – the 'middle ages' of life on Earth - and is split into to three geological periods: the Triassic, Jurassic and Cretaceous. The Jurassic Coast is designated a World Heritage Site partly because the rocks form an almost complete record of the Mesozoic. The fossils trapped in those rocks are the record of life during that time, giving us glimpses at lost habitats, vanished ecosystems and the slow evolution of life on Earth. This is one of the most exciting stories from the Jurassic Coast and, with new discoveries made almost every year, it is one that is still developing.