Last year at the NWTF convention, I took a jaw bone up to several wildlife biologists, Terry Drury and others. Basicaly what I gathered was you cant accrately look at a jaw and age a deer. Maybe you can sometimes but deer primarily eat different foods in different areas even in the same state, they also eat different foods in the exact same location based on acorn crop and other things. The deer i killed was atlest six based on trail cam photo's, noone at the convention could age him past 5. Some said definately mature and some said 5+ but thats the best I got.. Apparently Biologists have some method of taking individual teeth and putting them under a microscope and getting a accurate age, but i dont know much about that...