On the basis of radiographs, Holyoak claimed that the mandible of the broad-billed parrot was weakly constructed and suggested that it would have fed on soft fruits rather than hard seeds. As evidence, he pointed out that the internal trabeculae were widely spaced, that the upper bill was broad whereas the palatines were narrow, and the fact that no preserved upper rostrum had been discovered, which he attributed to its delicateness. The British ornithologist George A. Smith, however, pointed out that the four genera Holyoak used as examples of "strong jawed" parrots based on radiographs, "Cyanorhamphus", "Melopsittacus", "Neophema" and "Psephotus", actually have weak jaws in life, and that the morphologies cited by Holyoak do not indicate strength. Hume pointed out in 2007 that the mandible morphology of the broad-billed parrot is comparable to that of the largest living parrot, the hyacinth macaw, which cracks open palm nuts with ease. It is therefore probable that the broad-billed parrot fed in the same manner.