Response of bonnet macaque dyads to an acute foraging task under different motivational conditions.

To explore behavioral patterns in bonnet macaque mother-infant dyads under environmental challenge, the motivation of infants to contact their mothers during a 1-hr foraging period was manipulated in two ways. First, sessions were given in which the infants were separated from their mothers for 3 hr prior to the foraging period. Second, sessions were given in which the infants were allowed access to food prior to the foraging period, thereby presumably reducing their motivation to separate from mother to seek food for themselves during the foraging period. Neither manipulation resulted in heightened conflict within the dyads. Separation of the infants prior to the foraging period did result, in general, in mothers forfeiting foraging task engagement to attend to their infants. The extent to which a mother exhibited this pattern correlated with her level of foraging effectiveness.