geoffroy's tamarin has a varied diet that includes fruits, insects, exudates (gums and saps), and green plant parts. the diet varies seasonally. a study by paul garber estimated that the diet was made up of 40% insects, 38% fruit, 14% exudates (almost entirely from "anacardium excelsum" cashew trees), and 8% other items. another study, on barro colorado island, showed 60% fruit, 30% insects and 10% green plant parts, including large amounts of elephant ear tree ("enterolobium cyclocarpum") sap. another study showed a diet about equally split between insects (mostly grasshoppers) and fruit. unlike marmosets, tamarins do not have dentition adapted for gouging trees, so geoffroy's tamarin eats sap only when it is easily accessible. it generally hunts for insects by making quick movements on thin, flexible supports. in contrast, it generally feeds on sap while clinging to large vertical tree trunks.