The article presents a study that evaluates the ability of the Cerrado's marmoset, scientifically known as Callithrix penicillata to detect fruit under two different light conditions, the brightly illuminated and dimly illuminated environments. It mentions that among the placental mammals, only primates possessed a trichromatic color vision, however, this condition is not uniformly present to all primates species. Further, the ecological role of this genetic difference about the two species still remains unclear, but, some studies show that dichromats and trichromats appear to have different abilities towards detection of colored fruits against a background of leaves.