Continuity mistake: Near the end we see Booth digging up some bodies. His grip on the shovel changes instantly from both hands at the top of the shovel handle to one half way down the handle. (00:36:20)
Continuity mistake: The amount of dirt on the skull Bones finds near the end changes drastically. (00:36:00)
Continuity mistake: When going through the photos, Bones is looking at one of the victim in a field. Camera changes and now it is one of the victim's face close up. (00:11:00)
Continuity mistake: When Booth places the beaker of Hodgin's beetle, Zac's beetle swaps place on the table instantly. It goes from left of the beaker to right. (00:06:35)
Continuity mistake: The lawyer gives Booth the file on Howard Epps and he opens it with a picture on the left hand (screen right) side. Camera shows the file open and that photo is now on the right under a bulldog clip there fore making it impossible the photo fell and swapped sides when opened. The picture also rotates. (00:03:50)
Continuity mistake: Angela asks Bones what the rush is. When she does, Bones' ponytail is down her back. Camera changes angle and now it's over her shoulder without moving her head. (00:12:45)
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.