Researchers at the University of California, Riverside's Bourns College of Engineering say the fist-like club of a peacock mantis shrimp can create a force more than 1,000 times its own weight. The club of the 4-inch crustacean accelerates underwater faster than a 22-caliber bullet. The researchers found the surface of the club is made of strong bone-like mineral which supports the impact during a strike. Inside, organized layers of chitin fibers act as a shock absorber. The shrimp uses its powerful club to crush clams and other shells but researchers think emulating the design could lead to better body armor.