USE OF EXPERIMENTER-GIVEN CUES DURING OBJECT-CHOICE TASKS BY CHIMPANZEES (PAN-TROGLODYTES), AN ORANGUTAN (PONGO-PYGMAEUS), AND HUMAN INFANTS (HOMO-SAPIENS)

In a series of experiments, chimpanzees (Pan troglodytes), an oranguta n (Pongo pygmaeus), and human infants (Homo sapiens) were investigated as to whether they used experimenter-given cues when responding to ob ject-choice tasks. Five conditions were used in different phases: the experimenter tapping on the correct object, gazing plus pointing, gazi ng closely, gazing alone, and glancing without head orientation. The 3 subject species were able to use all of the experimenter-given cues, in contrast to previous reports of limited use of such cues by monkeys .