The use of conspecific phenotypic states as information during reproductive decisions

Conspecifics that individuals encounter while foraging can provide a rich source of information about resource quality and levels of competition in the environment. Social learning theory predicts that animals should respond to cues from those individuals that provide the most reliable information. In this study, we explored the effect of the reproductive state and behaviour of individual sources of information on the behavioural and physiological reproductive decisions of the walnut-infesting fruit fly, Rhagoletis suavis. We demonstrate that female flies held in the presence of reliable sources of information about resource quality and/or level of local competition (reproductively active females) mature and lay eggs more readily than those in the presence of unreliable information sources (reproductively inactive females). The occurrence of such sophisticated use of social information in a nonsocial insect indicates its potential ubiquity and importance in the ecology and evolution of populations.