[The behavior of tamarin monkeys during the learning and realization of instrumental food habits in a competitive situation].

Special features of competitive behavioural organization have been revealed during formation and realization of simple feeding and instrumental reflexes elaborated simultaneously in family pairs of marmoset monkeys. In contrast to other anthropoid species, male and female marmosets performed feeding reactions of different levels of complexity with equal efficiency. The differences between male and female marmosets concern the structure of competitive behaviour: males showed more active forms of competition under equal number of the given reinforcement, whereas passive forms of behaviour were more typical in females. The latter produced intensive vocalization in comparison with males. Stabilization of competitive activity was accompanied by the decrease of active forms of competition and by standardization of individual behaviour. The increase in the number of behavioural strategies was observed in family groups under sophisticated experimental conditions.