The Ghost in the Machine - S8-E9
Other mistake: Bones states she doesn't like to make assumptions in sex based on just the skull. However this is something she has done from the start. (00:01:10)
The Party in the Pants - S8-E22
Other mistake: The body falls from the excavator revealing there is no other debris in the excavator. However when the team get there they are told that the load in the bucket fell on the body, crushing the head. (00:03:15)
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.