The Teacher in the Books - S10-E12
Trivia: This episode heavily features the fact Dr. Brennan is now on Twitter. During the original run of the show, there was an active Twitter account in the guise of Dr. Brennan. The account features all the tweets and selfies we see Bones post in the episode, and during the airing of new episodes "Dr. Brennan" would be live tweeting about the show. However its unclear if it was Emily Deschanel tweeting or an employee of Fox. The account (which has been inactive since 2016) is viewable here https://mobile.twitter.com/DrBrennan?lang=en.
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.