You're 70 feet underwater -- face to face with one of the sea's friendliest creatures. National Geographic photographer Flip Nicklin and his wife Linda, a naturalist and educator, invite you to study the amazing behavior of the beloved dolphin. Learn the difference between an orca and a bottlenose. Witness a dophin baby nursed with mother's milk. Discover how these social mammals echolocate and communicate. Flip is a veteran of 5,500 dives worldwide, and this compelling book aims to encourage active concern and support for these smiling sea creatures whose intelligence demands our kinship.  (BST119, $6.95)