I'm just trying to figure out what it is that you're laughing at. Don't you think that they can pretty well identify the bone of a mammoth? Let's see...Austria...that would make them babies of whatever humans were living in Austria at that time? Seems logical. Why wouldn't it be a grave? You don't have to be a Christian or a Jew to bury your dead lovingly.
I'm thinking practically. You bury your dead to keep the smell down and to keep animals away.