Upside Down is the Only Way to Chew, Man!

Newton, like all dogs, likes to chew on stuff, and he particularly enjoys his rawhide bones. However, he does something that I think is a bit odd. He rolls over on his back while chewing like so:

This is wierd, right? I swear I have never seen a dog do this before. And Newton seems to do it when he's REALLY into a bone. It's like it's better if he chews it upside down. Silly dog!