Yes, tarsiers are primarily nocturnal animals, meaning they are most active during the night. Their behavior is adapted to thrive in low-light conditions, and they have several physiological and behavioral adaptations that support their nocturnal lifestyle.
Tarsiers have large eyes in proportion to their body size, which allows them to gather more light and enhances their night vision. Their eyes are specialized for low-light conditions, and they have a reflective layer behind the retina called the tapetum lucidum, which improves their ability to see in dim light.
In addition to their visual adaptations, tarsiers also have other traits suited for a nocturnal lifestyle. They possess large ears that aid in detecting high-frequency sounds, which can be particularly useful for locating prey or avoiding predators in the dark. Tarsiers also have a keen sense of hearing to compensate for the reduced visibility at night.
During the daytime, tarsiers typically rest and sleep in tree holes, dense vegetation, or other well-concealed locations. They become active at dusk and spend the night hunting for insects, small vertebrates, and other prey. Their ability to leap and move adeptly through the trees is well-suited to their nocturnal foraging behavior.
While tarsiers are primarily nocturnal, it's worth noting that there are some species, such as the pygmy tarsier, that exhibit a more crepuscular (active during twilight) behavior, being active during the dawn and dusk periods. However, the majority of tarsier species are primarily active at night.