Marmosets are much cuter than they appear in the photo, and are fascinating primates. Usually only one female breeds in the group, and the rest of the monkeys help raise the babies.
Marmosets usually give birth to twins, once or twice a year.
My graduate students and I are interested in finding out more about how these amazing monkeys think, and the unique cognitive adaptations they have evolved. We observe their behavior while they forage in naturalistic environments, and also record the sounds they make. For more information on marmosets and other primates, check out the Primate Information Center site.