ABSTRACT
Skeletal tissues in general and bone in particular are able to respond to functional influences in a manner that leads to an optimal design for the prevailing functional requirement. The architecture of bone from the tissue level to that of the organ and system arises from two major input factors. The first is the inherited genetic information that accounts for interindividual and interspecies differences. This genetic component can be considered in two ways. Evolutionary drives that determine the characteristic skeletal form found in particular species, for example, the dense long bones without a marrow cavity seen in the manatee (
Trichechus manatus
) to the large-diameter thin-walled and internally braced long bones of birds such as the large flying species, e.g., swan (Fig. 26.1). This immense biodiversity in bone architecture driven
by evolutionary pressures is accompanied by the superimposition of functional adaptation to short-term changes in the lifestyle of the individual, the second major factor. The ability of a tissue to respond to mechanical demands is highly developed in bone.
