Small Monkeys

Callithrix Jacchus

Common Marmosets  are very small monkeys with relatively long tails. Males and females are of similar size with males being slightly larger. Males have an average height of 19cm and females have an average height of 18cm. Males weigh 256g on average and females weigh 236g on average. The pelage of the marmoset is multi-coloured, being sprinkled with brown, grey and yellow. It also has white ear tufts and the tail is banded. Their faces have pale skin and have a white blaze on the forehead. The coats of infants are brown and yellow coats with the ear tuft developing later.

Distribution and habitat

Common Marmosets are native only to east-central Brazil. They have been introduced into other areas and live within cities of Rio de Janeiro and Buenos Aires, Argentina. Marmosets can be found in a number of forest habitats. They live in Atlantic coastal forests as well as semi-deciduous forests farther inland. They can also inhabit savanna forests and riverine forests. Marmosets are successful in dry secondary forests and edge habitats.


They eat fruits, flowers, nectar, plant exudates (gums, saps, latex) and animal prey (including frogs, snails, lizards, spiders and insects). Marmosets have morphological and behavioural adaptations for gouging tree trunks, branches and vines of certain species to stimulate the flow of gum, which they eat.

Life expectancy and breeding

Common Marmosets live in stable extended families with only a few members allowed to breed. A marmoset group can contain as many as 15 members, but a more typical number is nine. A marmoset family usually contains 1-2 breeding females, a breeding male, their offspring and their adult relatives, be it their parents or sibling. Males do not mate with breeding females that they are related to. Marmosets may leave their natal groups when they become adults, in contrast to other primate species who leave at adolescence.

Conservation status

Least concern