Social development in three species of macaque (Macaca mulatta , M. fascicularis , M. tonkeana ): A preliminary report on the first ten weeks of life.

The development of social relations was studied in 11 infant monkeys over the first ten weeks of life : 5 subjects in a rhesus macaque group (Macaca mulatta ), 3 in a long-tailed macaque group (M. fascicularis ) and 3 in a Tonkean macaque group (M. tonkeana ). Tonkean infants were found to interact with many different group members because of the permissiveness of their mothers, while social contacts of rhesus and long-tailed infants are less varied due to the restrictiveness of their mothers. These differences were consistent with patterns of adult-adult interactions, Tonkean macaques showing less intense agonistic interactions than the other two species.