While a number of "penguin books" cover the natural history, mainly of breeding aspects, few address in much detail the incredible aquatic nature of these creatures. A huge amount of information has been amassed over recent past decades thanks to dramatic advances in microelectronics, bio-logging and maturation of some long-term studies of penguin life history. This work represents an integration of all these data with charts, maps and graphs, along with richly illustrated photos by experts in the field.