World Book's Learning LaddersUnder⊕WORLDBOOKwww.worldbook.comWorld Book,Inc.180 North LaSalle StreetSuite 900USAFor information about other World Book publications,visit our website at www.worldbook.com or call1-800-W0 RLDBK(967-5325).For information about sales to schools and libraries,call 1-800-975-3250 (United States);1-800-837-5365(Canada).2008 revised printing2008 World Book,Inc.All rights reserved.This book may not be reproduced in whole or in part inany form without prior written permission from the publisher.WORLD BOOK and the GLOBE DEVICE are registered trademarks or trademarks of World Book,Inc.Library of Congress Cataloging-in-Publication DataStaffExecutive CommitteeUnder the sea.President:Jim O'RourkeVice President and Editor in Chief:Paul A.KobasaSummary:"Introduction to animals that liveVice President,Finance:Donald D.Kellerin the sea using simple text,question and answerVice President,Marketing:Jean Linformat,illustrations,and photos.Features includeVice President,International Sales:Maksim Rutenbergpuzzles and games,fun focts,o resource list,andDirector,Human Resources:Bev Eckeran index"--Provided by publisher.Editorial1SBN978-0-7166-7731-4Director,Digital Print Content Development:Emily Kline1.Marine animals--Juvenile literature.Editor,Digital Print Content Development:Kendra MuntzI.World Book.Inc.Senior Editor:Shawn BrennanQL122.2.U5332007Senior Editor:Dawn Krajcik591.77-dc22Manager,Indexing Services:David Pofelski2007018917Manager,Contracts Compliance(Rights Permissions):Loranne K.ShieldsWorld Book's Learning LaddersDigital1sBN978-0-7166-7725-3(6et,hc.)Director,Digital Product Development:Erika MellerDigital Product Manager:Jonathan WillsAlso available as:ISBN 978-0-7166-7768-0 (e-book,Leaming Hub)Graphics and Design15BN978-0-7166-7769-7(e-book.Spindle)Senior Art Director:Tom Evans1SBN978-0-7166-7770-3(e-book,EPUB3)Coordinator,Design Development and Production:Brenda B.Tropinski1SBN978-0-7166-7771-0(e-book,PDF)Manufocturing/Pre-PressPrinted in China by Shenzhen Wing King TongManufacturing Manager:Anne FritzingerPaper Products Co,Ltd.,Shenzhen,GuangdongProofreader:Nathalie Strassheim1 Ith printing May 2017This edition is an adaptation of the Ladders series published originallyby T&N Children's Publishing,Inc.,of Minnetonka,Minnesota.Photographic credits:Cover:Willyam Bradberry,Shutterstock p5:blickwinkel/AlamyImoges;p6:Michoel Patrick O'Neill,Photo Researchers;p8:Jeff Rotman,AlamyPremier/Alamy Images;p18:Chris A Crumley,Alamy Images;p19:Art Wolfe,Getty