Apatosaurus which Marsh had described "Brontosaurus". Most of the skeleton was found, and after comparison with both "Brontosaurus" and "Apatosaurus ajax", Riggs realized that the holotype of "A.ajax" was immature, and thus the features distinguishing the genera were not valid. Since "Apatosaurus" was the earlier name, "Brontosaurus" should be considered a junior synonym of "Apatosaurus". Because of this, Riggs recombined "Brontosaurus excelsus" as "Apatosaurus excelsus". Based on comparisons with other species proposed to belong to "Apatosaurus", Riggs also determined that the Field Columbian Museum specimen was likely most similar to "A.excelsus". Despite Riggs' publication, Henry Fairfield Osborn, who was a strong
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