Exactly what ARE VRML animations stored as?

I've been trying to work with animated VRML files in Java 3d for about a week and the one thing I can't figure out is exactly what object is suppose to dictate the animation of the scene it's attached to and, better yet, how to invoke it. I saw something online about an Interpolar object, but whenever I try to dissect the scene's hierarchy, I can't find any sort of object like that. Anyone have ideas as to why?

I could post the code for the loader class I'm using if it'll help, but I warn you that it's VERY long and I'm not sure I can fit it all into a single post.