Isle of Wight Fossils Reveal Sail-Backed Dinosaur Named for Ellen MacArthur

Palaeontologists have identified a new species of iguanodontian dinosaur from 125-million-year-old fossils held at the Dinosaur Isle Museum on England’s Isle of Wight. The animal, distinguished by unusually elongated neural spines that formed a prominent sail along its back, has been named Istiorachis macarthurae—‘sail spine’ in ancient Greek combined with a tribute to Dame Ellen MacArthur, the island-born yachtswoman who set the 2005 world record for the fastest solo circumnavigation. Lead author Jeremy Lockwood, a retired medical doctor now completing a PhD at the University of Portsmouth and the Natural History Museum, discovered the species after re-examining bones originally excavated in the 1970s. His analysis, published 22 August in the journal Papers in Palaeontology, showed that the specimen’s spine differed markedly from the two previously known iguanodontians found on the island, expanding the region’s recognised dinosaur diversity to at least 10 new species in the past six years. Researchers believe the sail served mainly for visual signalling—either to attract mates or intimidate rivals—rather than for temperature regulation or fat storage, echoing display structures seen in modern reptiles. The medium-sized herbivore would have been comparable in bulk to today’s American bison. The discovery underscores the scientific value of re-evaluating museum collections and cements the Isle of Wight’s status as one of Europe’s richest sites for Early Cretaceous vertebrate fossils.