It's hard to improve upon nature: Its intricate forms and patterns were molded over millennia of evolution and fine-tuned to precision. In this gallery of biomimicry--the practice of emulating nature to solve human problems--we take a look at what medicine is learning from the animal kingdom.

The squid beak is a feat of natural engineering. Made entirely of organic materials like chitin, it is both extremely rigid at its tip, yet soft and supple at its base. The beak's dual nature helps explain how the boneless squid can tear its prey limb from limb without cutting itself with the base of its beak.

This crucial insight was provided by a team of researchers from the University of California, Santa Barbara, who suggested that graduated materials like the beak could find broad use in medicine and biotechnology. For instance, scientists could develop an artificial limb that could emulate the elasticity of cartilage on one end and the rigidity of bone on the other. In addition to their functionality, these malleable materials would have the benefit of being both extremely versatile and benign to surrounding tissues, unlike current devices made purely of metal or ceramic.