Understanding food selection will require considerably more than reductionist analyses of the internal workings of individual animals. To understand food choice we will have to examine not only the physiology and behavior of individuals, but also the biological and social environments within which individuals select items to ingest. The biological environment determines patterns of food availability and, over evolutionary time, provides selective pressures which shape sensory-affective responses to flavors, making them adaptive with respect to local conditions. Direct experience of the consequences of ingesting potential foods and interaction with conspecifics that have eaten various foods both affect food choices. These multiple influences, acting at different levels of organization, can bias food selection by individuals in either adaptive or maladaptive directions, depending on the characteristics of the environment in which feeding occurs. The need to understand the relationship between internal organization, individual and social experience and ecological demands may make food choice the most difficult of the core aspects of feeding behavior to analyze satisfactorily.