Kamar yadda Mantell ya lura, ragowar da yake aiki da ita ba kamar kowane dabba mai rarrafe na zamani ba ne, musamman a cikin rashin hakora, siffar kwano na ƙananan jaw symphysis, wanda ya sami mafi kyau idan aka kwatanta da na sloth mai yatsun hannu biyu da kuma sloth na ƙasa Mylodon. Ya kuma ba da shawarar cewa Iguanodon yana da harshe na prehensile wanda za a iya amfani da shi don tattara abinci, kamar giraffe. Ƙarin cikakkun ragowar sun nuna cewa wannan kuskure ne; alal misali, ƙwayoyin hyoid da harshe ke tallafawa, yana nuna cewa an gina tsoka, harshe mai mahimmanci don abinci a cikin takalma.
Mantell