JOHN MONGILLO currently writes school science textbooks. He has worked as an editor-in-chief for McGraw-Hill and as a science editor for Houghton Mifflin. He has both a bachelor of science and a master of science and has taught science for several years.LINDA ZIERDT-WARSHAW is a science editor and writer. She has worked as senior science editor for Globe Book Company and managing editor of The Paper Magazine. She is co-author of Environmental Science: Ecology and Human Impact (1995).