Archeology is one of the most interesting fields out there. It uses bones, skeletal analysis, bone composition, grinding of teeth can show what types of food were eaten. You can actually tell if animals had sounds and what they might have sounded like. You can get a sense of age and the environment they lived in by examination of the soil around where they are fossilized - above them is earlier and below is later. You can get a sense of the environment by the sediment surrounding. And then it all gets pretty complex. So interesting!