Members of the genus Aotus are traditionally considered strictly nocturnal, however, in
recent years cathemeral habits have been described in a single species of owl monkey …

Strepsirrhine and haplorhine primates exhibit highly derived features of the visual system
that distinguish them from most other mammals. Comparative data link the evolution of these …

The study of activity rhythms, their potential zeitgebers and masking factors among free-
ranging primates has received relatively little attention in the past. Most primates are diurnal …

It is firmly believed that ancestral primates were nocturnal, with nocturnality having been
maintained in most prosimian lineages. Under this traditional view, the opsin genes in all …

Owl monkeys, genus Aotus, are distributed from Panama to the northeast of Argentina and
from the highlands of the Andes to the Atlantic coast. They are relatively small arboreal …

Among primates, nocturnal species exhibit relatively larger orbital apertures than diurnal
species. Most researchers have considered this disparity in orbital aperture size to reflect …

Owls and nightbirds are nocturnal hunters of active prey that combine visual and hearing
adaptations to overcome limits on sensory performance in low light. Such sensory …

Typical avian eyes are phenotypically engineered for photopic vision (daylight). In contrast,
the highly derived eyes of the barn owl (Tyto alba) are adapted for scotopic vision (dim light) …

Xlimals avoid competing with one another by evolving more or less specialized ways of life.
Such specialization may take the form of be ing bigger or smaller than other animals, of …

According to the “nocturnal visual predation hypothesis”(NVPH), the convergent eyes and
orbits of primates result from selection for improved stereoscopic depth perception to …