Kerry Sanders of the "Today" show gives an exclusive tour of the only working underwater laboratory in the world, which is owned by Florida International University. Known as Aquarius, the lab is anchored on the ocean floor, nine miles off the coast of Key Largo, Fla., allowing marine scientists (and even NASA engineers) to do weeks' worth of work in a much shorter period of time.

Related on MNN: Fabien Cousteau to live at Aquarius for 31 days