In this nonfiction picture book an unidentified narrator follows one krill among billions as it pursues its existence, eating and eating while metamorphosing from one thing into another and trying to avoid being eaten. Krill are among the largest animals able to catch and eat phytoplankton, and they in turn are eaten by the largest animals ever to live on earth-blue whales-as well as by seals, penguins, and a host of other animals. That makes them...