“During the daily activities of life the bones of the skeleton, individually and collectively, are subjected to a variety of force systems. The response of the bones to these systems is a function, to a large extent, of the mechanical properties of the bones. Of course, the type, magnitude, direction, and point of application of the force as well as whether or not it is applied slowly, rapidly, repetitively, or for a long duration must also be considered. Additional variables include whether the bone is living or dead, embalmed or fresh, and the age, sex, race, and species of animal from which the bone is obtained. The specific bone and part of the bone being studied as well as its microscopic structure influence its mechanical properties as do the amount of moisture in it and the temperature at which the mechanical properties are determined.” (F. Gaynor Evans, 1973, preface)