The common marmoset (Callithrix jacchus jacchus) as a model for ethological research.

The uses and advantages of the common marmoset (Callithrix jacchus jacchus) as an animal model for ethological research were examined. It was found that this species had advantages over Old World primates for work on social behavior as a nearer approximation to the group structure occurring in natural conditions could be obtained in the laboratory. The small size of the common marmoset also made it easier to handle and cheaper to maintain. The adult female gave birth at five-month intervals and usually reared twin offspring. This, and the short generation time, made it an ideal model for mother-infant behavioral studies. The common marmoset was also shown to be a useful model for studies of social play, especially for categorizing the changes in playful behavior with age, and the relationship of the patterns seen in play to other behaviors. It was also suggested that it may be an ideal model for experimental studies of play. Other suggested uses included studies of the relationship of food supply and feeding habits to territory size and group structure, and of the advantages to elder offspring of helping to rear younger siblings. As a result of these observations the common marmoset was considered to have great potential as a model for ethological research, both in its natural habitat and in the laboratory.