Jurassic Coast cliffs, spanning the Mesozoic, documenting 185 million years of geological history. The site can be best viewed from the sea, when the dipping nature of the rock strata becomes apparent. In East Devon, the coastal cliffs consist of steep cliffs of red sandstone from the Triassic, and at Budleigh Salterton, the gravel cliffs contain red quartzite pebbles which accumulate on the beach below as Budleigh pebbles, locally protected.Further east at Ladram Bay, more sandstone cliffs give rise to spectacular red sandstone stacks. Around Lyme Regis and Charmouth the cliffs are of Jurassic clays and shale, and landslips are common. Chesil
Sea urchin with just six species known from the Permian period. Only two lineages survived this period's massive extinction and into the Triassic: the genus "Miocidaris", which gave rise to modern cidaroida (pencil urchins), and the ancestor that gave rise to the euechinoids. By the upper Triassic, their numbers increased again. Cidaroids have changed very little since the Late Triassic, and are the only Paleozoic echinoid group to have survived. The euechinoids diversified into new lineages in the Jurassic and Cretaceous periods, and from them emerged the first irregular echinoids (the Atelostomata) during the early Jurassic. Some echinoids, such as "Micraster" in