Also, the hyoid bone is the only "floating bone" in the human body. It's not attached to any other bones. So it would be the easiest bone for a small animal or bird to remove without a lot of damage to other bones. ETA Caylee Anthony's hyoid bone was never found either. Since it isn't attached to other bones I suspect it's common for it to be missing when a body is fully skeletonized. Of course I'm not sure if that's true. But it makes sense to me.