pt. 1. Partners in communication : Prey-predator interactions -- Communication between rivals -- Mate selection. pt. 2. Methods of communication : The fallacy of species-specific signals -- Movements and ritualization -- Vocalizations -- Body parts that serve as signals -- The use of color for showing off -- Chemical communications. pt. 3. The handicap principle in social systems : Testing the bond -- Parents and offspring -- Babblers, competition for prestige, and the evolution of altruism -- The social insects : why help the queen? -- The parenting couple -- Social amebas (cellular slime molds) -- Parasite and host -- Information centers. pt. 4. Humans : Humans.