Family Aotidae (Night Monkeys)

Abstract

Night monkeys, also sometimes called douroucoulis, belong to the genus Aotus, a name derived from the latin words “a,” meaning without, and “otis,” meaning ear. This name references their inconspicuous ears (pinnae) usually hidden by dense fur. Several taxonomic issues remain unsettled, such as the classification of Aotus at the family and subfamily levels and the number of recognized species and subspecies within the genus. The earliest known forms of night monkeys are an extinct species from the Miocene (Aotus dindensis) and an extinct Aotus-like species with enlarged ocular orbits from the late Oligocene (Tremacebus harringtoni), indicating that the Aotus lineage has long been separated from the other genera of New World primates. The geneticist N. Ma suggested that the variability observed in the karyotype and other characteristics of Aotus may be the result of populations being isolated in forest refugia during glacial periods in the Pleistocene...