Many of the living types of spider can be traced back to the Mesozoic Era. For example, a tarantula relative is known from Late Triassic rocks (dating back 210 million years) in France, and relatives of web-spinning species are known from the Jurassic Period. In particular, a Lower Cretaceous specimen from Spain shows three claws on the end of each leg, which modern spiders use for walking on their webs.