The Plain in the Prodigy - S5-E3
Factual error: When Bones and Booth go to visit Levi's parents and Sarah's brother yells at her that she is needed at home, when he gets into the buggy you see him wearing a wedding ring. Amish wear a beard to indicate marital status, not jewelry it is against the religion to wear any decoration including wedding rings. (00:08:50)
Answer: Since the palatine bone is a bone that helps form the mouth it has a lot to do with speaking. The shape of it differs a lot depending on your ethnic background. I would guess that they, in the show, meant that the person's bone tells that they were Japanese and that it was "made for the purpose of speaking Japanese." That's what I'd assume anyway. I've studied molecular biology though, so I'm not an expert on bones.