Embryonic Origins
The splanchnocranium is derived from the neural crest cells (also responsible for the development of the neurocranium or, teeth and adrenal medulla) or from scleratone found in the somite block of the mesoderm. As with the neurocranium, in Chondricthyes and other cartilaginous vertebrates, they are not replaced via endochondral ossification. In tetrapods, such as amphibians and reptiles, the columella connecting to the tympanum is derived from the splanchnocranium. In mammals, the splanchnocranium derives the bones of the middle ear, the malleus, the incus and stapes.
Read more about this topic: Facial Skeleton
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