Scientists study penguin's physiology to learn how they can dive to depths of 300m (1500ft). Penguins spend much of their life in the ocean hunting for krill, fish and squid. Unlike humans, penguins don't suffer from many problems associated with diving, such as decompression sickness (the bends), shallow water black-out, and free-radical damage to tissues. Researcher's work understanding penguins may someday be applicable to anesthesiology and other medical applications. Credit: Nicolle Rager Fuller, National Science Foundation