Geoffroy's Marmoset, sometimes called the White-headed Marmoset, lives in coastal rainforests of southeast Brazil.
They live in family groups of up to a dozen.
Like other marmosets, their teeth (long incisors) are adapted to chisel small holes in trees to drink sap and gum in addition to taking fruit, flowers, insects and snails.
Parent with young twins. Twins are usual for marmosets. Father, mother and adult relatives share baby-sitting duties.
Most primates have hands with fingers but marmosets have claws to run up trees and tear into tree bark.