Mother and Child in the Bay - S2-E2
Revealing mistake: When Bones and Booth are driving in his SUV talking about Abraham in the Bible, you can see that Bones' side window is lowered almost all the way down, but her hair is perfectly still and not being blown around as it normally would be.
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.