Trace fossil footprint
Swanage, and the Lower Cretaceous Purbeck Beds, are famous for dinosaur footprints. This specimen is a cast, meaning the footprint itself was filled with sediment. The surrounding rock into which the dinosaur pressed its foot, has come away leaving a positive cast of what was originally a depression in the mud. The massive size and the short toes suggest that this is an Iguanadon print.
So why are there lots of footprints but hardly any fossilised dinosaur bones? The answer is simple: each dinosaur made millions of footprints during its life but in the case of Iguanadon, it only had two legs. Therefore there are far more footprints with the potential to become fossilised than there are bones of the animals that made them.
Find out more on the trace fossils pages.