Abstract
At an evolutionary level, behavioural manipulation occurs when an individual – the manipulator – increases its own fitness through altering or channelling the behaviour of another individual in ways that are detrimental to that of the manipulated individual. It follows that behavioural manipulation is not necessarily limited to host–parasite systems. This chapter reviews the literature on behavioural manipulation outside the world of parasites, and introduces a gradual categorization, ranging from sensory exploitation to physiological manipulation, based on the degree of behavioural control imposed by one individual over another. Although the main modes used by parasites to achieve behavioural manipulation have been reported in free-living species, claimed cases of manipulation might be prone to false identification and misinterpretation, often because of a lack of careful analysis. Finally, the chapter discusses the similarities and dissimilarities in behavioural manipulation between parasitic and free-living organisms, emphasizing differences in cognitive abilities and the duration of the manipulative interaction.