geoffroy's tamarin can give birth throughout the year, but the birthing peak is from april to june. a single infant or twins can be born, although it is not uncommon for one of the twins to perish within the first few months. the gestation period is believed to be about 145 days, similar to the cottontop tamarin. the interbirth period ranges between 154 and 540 days, with an average of 311 days. the longer interbirth periods occur after twins. infants weigh between and are born fully furred. the infant's fur is colored differently than the parents'; the infant has black fur on the body and tail, with a beige blaze and white face. the infant coloration reduces the visibility of white, which is associated with aggressive displays by the species.