Diplodocus now common scientific opinion that "Seismosaurus hallorum" is a species of "Diplodocus". This genus of dinosaurs lived in what is now mid-western North America at the end of the Jurassic period. "Diplodocus" is one of the more common dinosaur fossils found in the middle to upper Morrison Formation, between about 154 and 152 million years ago, during the late Kimmeridgian age. The Morrison Formation records an environment and time dominated by gigantic sauropod dinosaurs, such as "Apatosaurus", "Barosaurus", "Brachiosaurus", "Brontosaurus", and "Camarasaurus". "Diplodocus" is among the most easily identifiable dinosaurs, with its typical sauropod shape, long neck and tail, and
Alan the Dinosaur vertebra encased within sandstone and measuring 145 mm in length. The fossil first went on public display in the Yorkshire Museum in June 2015. It was redisplayed as part of the "Yorkshire's Jurassic World Exhibition", which opened in March 2018. The exhibition features a virtual reality experience in which users can feed a digital reconstruction of Alan. Alan the Dinosaur Alan the Dinosaur is the name given to an unidentified Sauropodomoph fossil, found in Whitby in 1995, regarded as the oldest sauropod dinosaur found in the United Kingdom. It is now in the Yorkshire Museum. The fossil was discovered in