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Thesis (M.S.)

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The development and expression of the social skills necessary for an infant to become a functional member of its species-specific milieu are shaped by the transactions between the infant and its mother and between the infant and group members. Mechanisms underlying social development in rhesus monkeys (M. mulatta) were studied by monitoring two mother-infant dyads (one male, one female) during the brief separation of four juveniles from the social group. These juveniles varied in terms of relationship (sibling and non-sibling) and gender to the infant. Each juvenile was separated an hour each week for four consecutive weeks during the infant's fifth month of life. Data were collected on the mother-infant pairs during the removal of each juvenile from the social group and on 2 non-removal days when the colony was intact. Observations were recorded during 15 minute data sessions using a modified frequency scoring system in which the presence of absence of behaviors was recorded in each 15 second interval. The occurence of each behavior was also recorded.