Gr 5-8-Johnson tells how ornithologists began to study the language of birds, describing the methods of collecting, identifying, and transcribing their songs. She cites the research that has been done and several of the theories that have been developed to explain the complexities and subtleties of avian communication. Sharp, clear, full-color photographs accompany the information. The author also touches on the human and natural threats that affect the survival of songbirds. A factual and visual peek into a fascinating phenomenon.-Cynde Marcengill, Horry County Memorial Library, Surfside Beach, SC Copyright 2001 Cahners Business Information.