The two plates form the posterior part of the hard palate and the floor of the nasal cavity; anteriorly, they join with the maxillae.

Although a similar pattern was present in primitive tetrapods, the palatine bone is reduced in most living amphibians, forming, in frogs and salamanders, only a narrow bar between the vomer and maxilla.

[4] Early fossil reptiles retained the arrangement seen in more primitive vertebrates, but in mammals, the lower surface of the palatine became folded over during evolution, forming the horizontal plate, and meeting in the midline of the mouth.

This forms the rear of the hard palate, separating the oral and nasal cavities, and making it easier to breathe while eating.

In birds, the palatine bones remain separate, long the sides of the rear part of the upper jaw, and typically have a mobile articulation with the cranium.