The age and season of death of mammals, as well as other aspects of their life history, can be estimated from seasonal bands in dental cementum that result from variations in microstructure. Scanning electron micrographs of goats fed controlled diets demonstrate that cementum bands preserve variations in the relative orientation of collagen fibers that reflect changes in the magnitude and frequency of occlusal forces from chewing different quality diets. Changes in the rate of tissue growth are also reflected in cementum bands as variations in the degree of mineralization.