White-eared titi of 11.5 hours, 2.7 hours of which is spent feeding. Titi monkeys sleep on branches at least above the ground. In the same manner as resting during the day, titi monkeys huddle together and twine tails to sleep. Though there is little published research on the diet of the white-eared titi, titi monkeys in general are omnivores that eat fruit, leaves, insects, and seeds. They mostly eat leaves, especially protein-rich young leaves and leaf buds, so a significant period of the day is spent resting to digest the cellulose. They consume more than 100 different species of plants and fruit.
White-eared titi species within the genus "Plecturocebus". Although the exact position of species within the genus "Plecturocebus" in the "P. donacophilus" group with the Rio Beni titi ("P. modestus"), Rio Mayo titi ("P. oenanthe"), Ollala brothers' titi ("P. olallae"), and white-coated titi ("P. pallescens"). The white-coated titi has sometimes been considered a subspecies of the white-eared titi, but they are treated as separate species in the latest edition of Mammal Species of the World. The white-eared titi is a medium-sized primate with grey to orange pelage. The species does not exhibit sexual dimorphism; the male's head and body length averages while females