While the three middle digits of each forelimb (digits II, III, & IV) were very thick and probably weight bearing, the outside fingers (digits I & V) were modified in different ways. The first digit was a simple sharp spike, as seen in "Iguanodon". Aside from defense, the thumb spike could possibly have also been used for breaking the shells of seeds or fruit. The fifth digit was somewhat opposable to the rest of the hand and may have been useful for grasping food.