Jackie Gaff has over 20 years' experience in illustrated books for children. Previously a nonfiction editor, she is now a full-time author with a real commitment to, and enthusiasm for, creating books that children both want and are able to read. Gaff is also the author of three other I Wonder Why books: I Wonder Why Fish Grew Legs, I Wonder Why Mountains Have Snow on Top, and I Wonder Why the Sahara Is Cold at Night.