Book excerpt: The oceans of the world are busy highways for creatures on the move. Plankton - small plants and animals, some so tiny they cannot be seen without a microscope - travel up to the surface and then down more than three thousand feet twice a day; eight-hundred-pound green turtles swim more than a thousand miles to lay their eggs; and spiny lobsters, forming long lines, walk across the ocean bottom. Award-winning science writer Seymour Simon and illustrator Elsa Warnick team again in this vivid companion to Ride the Wind: Airborne Journeys of Animals and Plants. Fascinating glimpses of the mysterious migration of sea creatures will enthrall and amaze young readers.