Abstract
1. Responsiveness to inanimate objects was studied in feral M. fuscata by: (a) observing reactions to naturally occurring objects, (b) placing novel toys along paths and on rocks, and (c) presenting novel dolls in conjunction with food, as in a conflict test. 2. Spontaneous manipulation seemed less frequent and less persistent than in laboratory primates. Children accounted for a vast majority of such activity. The dominant modes of reaction to novel objects were cautious in nature, albeit avoidance was often impossible to observationally distinguish from indifference, especially in adult males. Emotional displays were rare, presumably because of Ss' ability to make spatial adjustments and thus control the effective intensity of stimulation. 3. The larger a doll, or the closer it was to a food kettle, the fewer and the farther the approaching monkeys. With time more Ss began to approach, but adaptation was slow. 4. The data were discussed in relation to problems of social behavior and instrumentation, and to the general problem of measuring responsiveness in the laboratory and the field.