[1][5] Cebus olivaceus is known to dwell in tall, primary forest and travel over long distances during the day.

[6] These primates are medium-sized monkeys with distinctive "wedge cap" markings on their head and slightly longer limbs than other capuchins for jumping through the forest canopy.

Cebus olivaceus is a polygamous species that lives in groups of anywhere from 5-30 individuals with female-biased sex ratios.

Wedge-capped capuchin partake in several behavioral mechanisms to assert and maintain dominance within the group including: infanticide, when an infant is deliberately killed; grooming, used to facilitate social rapport; and alloparenting, which is when members of the group care for offspring that are not their own.

[9] The American Society of Mammalogists, IUCN Red List, and ITIS all follow this taxonomy, although only tentatively.

[5][10] Adult wedge-capped capuchins weigh approximately 3 kg, but weight varies moderately with sex.

[6] Their “wedge cap” starts between the eyes and extends backwards to cover the top of the head.

[7] Due to large physical variations in Cebus, taxonomists have frequently debated the exact classifications and details of the genus.

However, most agree that the wedge-capped capuchin shares the genus with four others: C. apella, C. albifrons, C. capucinus, and C. kaapori.

Phylogenetic analysis and constructions of cladograms have demonstrated that the wedge-capped capuchin is closely related to C.

[14][15] Wedge-capped capuchins prefer undisturbed primary forests in which they can move through the canopy (locomotion and limb morphology).

They occupy the rainforests of northern Brazil and Venezuela, as well as the drier forests along riverbeds in Guyana.

In general, these monkeys spend approximately equal amounts of time exploiting animal and plant resources.

Most of the plant food consumed is ripe fruit, the majority of which are figs, but also palm nuts, seeds, berries, flowering buds, shoots, barks and gums.

Their prey consists of snails, arachnids,[19] wasps, caterpillars, grasshoppers, ants, birds eggs, other small mammals[19] and many insects that inhabit palm crowns.

[19] While males and females spend about the same amount of time foraging for insects, they exploit different types of resources.

[21] Wedge-capped capuchins were shown to wash sandy food in four spontaneous occasions in both captive and wild populations.

Urbani found that food washing was a response to certain circumstantial problems and not through imitation or learning, as argued in studies of other species.

It is important to note that both male and female wedge-capped capuchins live as long as 36 years.

Genetically, it may pay for a male wedge-capped capuchin to kill an unrelated newborn, so that he can then mate with the mother sooner than if the baby was still alive.

However, in Valderrama's research,[25] the infanticidal male gained reproductive success from the killing in only one of the three cases studied.

[27] Grooming behavior plays an important role in the group dynamics of wedge-capped capuchins.

This may be largely due to the presence of two different grooming strategies among adult female wedge-capped capuchins.

This form of grooming helps establish alliances between females that may provide both social and material advantages.

This is common among many primate groups and indicates that young females may gain valuable experience in raising infants that will help them in the future.

In contrast to allomaternal behavior, parasitic nursing does not appear to give any benefits to the monkey providing the milk.

Such predators include jaguars, ocelots, tayras, boa constrictors, caimans,Annacondas, and collared peccaries.

In addition, alarm calls have been observed when the capuchin sees one of several birds, such as hook-billed kites, black vultures, green ibises, rufous-vented chachalacas, harpy eagles, or ornate hawk-eagles.

[32] Wedge-capped capuchins are ranked as an animal as least concern on the IUCN Red List of Threatened Species.