Mantellisaurus atherfieldensis

Formerly known as Iguanodon atherfieldensis, scientific understanding of this species has evolved as more information has been obtained from new research. This is one of the most complete skeletons of Mantellisaurus atherfieldensis discovered in Britain. It was collected by R.W. Hooley in 1917 on the Isle of Wight and dates back about 125 million years, to the Early Cretaceous Period. It was much more lightly built than its close relative, Iguanodon, and probably weighed about 1,500 kilogrammes. Its arms were one of its most remarkable features and were supported by robust shoulder bones. M. atherfieldensis's hands were uniquely multipurpose, their sharp spike thumbs being the dinosaur's only defensive weapon. The three middle fingers were strong and stiff, ending in small hooves for occasionally walking on all fours. The flexible fifth finger could grasp food and strip leaves from branches.