>>11926644bone structure is very well-designed (natural engineering at its finest). It is well-designed to dissipate (spread out) the shock very fast. So imagine you have a bone, and you whack it, the shock will spread throughout the bone's body very fast, hence each point in the bone does not have to withstand large shock impact. Steel, on the other hand, is hard, but lacks the structure (unless you build it like bone) to dissipate local impact. Thus, crack is very likely to form. Think of a steel beam, you whack it real hard at one point, other parts are okay, but that point will be dented or cracked. In fact, the bone structure, which is a grid, or matrix structure, is so good that many real-life engineering structures mimic that. For example: Eiffel tower is one very famous example of a matrix, grid-like structure, that was built with superb strength for little materials.
shamelessly robbed from Quora.
