Aquino, R., and F. Encarnacion. "Night Monkeys (Aotidae)  The black-headed night monkey is also found mainly in the Peruvian Amazon (central and upper Amazon), however its range extends throughout Brazil and Bolivia to the base of the Andes mountain chain.  The distribution of A. azare, extends further towards the Atlantic Ocean, spanning Argentina, Bolivia and the drier, south western regions of Paraguay, however unlike the other red-necked night monkey species, it is not endemic to Brazil. But the longevity of the site is threatened because of intense logging and illegal mining. Peruvian night monkeys reach sexual maturity at two years old. https://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/night-monkeys-aotidae, "Night Monkeys (Aotidae) The International Union for Conservation of Nature has the Peruvian night monkey listed as Endangered (IUCN, 2019).  Night monkeys represent a territorial species, territories are defended by conspecifics through the use of threatening and agonistic behaviours. These monkeys also provide food for predators. While the restrictive laws put into place by CITES are aiding in the reduction of these numbers, 4 out of 9 countries, show deficiencies in maintaining the standards outlined by CITES Increased attention and enforcement of these laws will be imperative for the sustainability of night monkey populations. Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at, How to improve snail memories with chocolate, Rare rusty-spotted cat kittens born in Berlin, Curious (and Terrifying) Creatures in Zoology, Plus One Obscure Christmas Gift Idea, So Skinny, So Bright: How Colour Change Predicts the Odds of a Chameleon Battle, Meet the Enormous King Ragworm, and its Adorable Offsider, the Slender Ragworm. Until 1983, all night monkeys were placed into only one (A. lemurimus) or two species (A. lemurinus and A. azarae). Aotus lemurinus (I. Geoffroy, 1843), Quindio, Dept. Scent can therefore be used as an effective method of navigation and reduce energy expenditure during subsequent foraging expeditions. Aotus trivirgatus (Humboldt, 1811), Rio Casiquiare, Duida Range, Venezuela. Research by nonprofits and academia have studied the status of the Peruvian Amazon and look to work with the Peruvian government to address its rapid deforestation and its effects on animals such as the Peruvian night monkey. Their hands are dark brown and are not entirely covered with fur. This species is monogamous, meaning that the individuals only have one partner at a time. The genus comprises eleven species which are found across Panama and much of South America in primary and secondary forests, tropical rainforests and cloud forests up to 2,400 metres (7,900 ft). "Banding patterns of the chromosomes of two new karyotypes of the owl monkey, Aotus, captured in Panama." jorgehernandezi. Consists mainly of fruits, nuts, leaves, bark, flowers, gums, insects, and small vertebrates. This has had a severe impact on the forest, and has made the population of the Peruvian night monkey very fragmented.  Unusual among the New World monkeys, they are monochromats, that is, they have no colour vision, presumably because it is of no advantage given their nocturnal habits. of Meta, east side of Cordillera Oriental.  To begin, resting during the day allows for decreased interaction with diurnal predators.  Therefore, olfactory communication in night monkeys is a result of sexual selection; sexually dimorphic trait conferring increased reproductive success. This is believed to have developed because it increases the survival of the infant and reduces the metabolic costs on the female.