Night monkey

Night monkeys[1]
A Panamanian night monkey in Panama
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Primates
Suborder:	Haplorhini
Infraorder:	Simiiformes
Parvorder:	Platyrrhini
Family:	Aotidae Poche, 1908 (1865)
Genus:	Aotus Illiger, 1811
Type species
Simia trivirgata Humboldt, 1811
Species
see text

Night monkeys, also known as owl monkeys or douroucoulis^[2] (/duːruːˈkuːliz/), are nocturnal New World monkeys of the genus Aotus, the only member of the family Aotidae (/eɪˈɒtɪdiː/). 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). Night monkeys have large eyes which improve their vision at night, while their ears are mostly hidden, giving them their name Aotus, meaning "earless".

Night monkeys are the only truly nocturnal monkeys with the exception of some cathemeral populations of Azara's night monkey, who have irregular bursts of activity during day and night. They have a varied repertoire of vocalisations and live in small family groups of a mated pair and their immature offspring. Night monkeys have monochromatic vision which improves their ability to detect visual cues at night.

Night monkeys are threatened by habitat loss, the pet trade, hunting for bushmeat, and by biomedical research. They constitute one of the few monkey species that are affected by the often deadly human malaria protozoan Plasmodium falciparum, making them useful as non-human primate experimental subjects in malaria research. The Peruvian night monkey is classified by the International Union for Conservation of Nature (IUCN) as an Endangered species, while four are Vulnerable species, four are Least-concern species, and two are data deficient.