PBS
Nh Pbs: Nature Works: Communication
This comprehensive site describes how communication is an adaptation that is important for survival.
McGraw Hill
Glencoe Biology: Ecological Behaviors: Self Check Quiz
Take this quick quiz to check comprehension of several ecological survival behaviors of animals.
PBS
Nh Pbs: Nature Works: Auditory Communication
Describing some of the reasons that animals make sounds, this website gives concrete examples that make acoustic (auditory) communication easy to understand.