Common Treeshrew (Tupaia glis)

The common treeshrew (Tupaia glis) is a small, diurnal mammal belonging to the order Scandentia and family Tupaiidae. It inhabits the tropical lowland forests of Southeast Asia, including the Malay Peninsula, Sumatra, Borneo, and adjacent islands. Adapted to both primary and secondary forest, it also frequents plantations, gardens, and suburban areas where dense understory provides cover. Adults have a head‑body length of 13–16 cm (5.1–6.3 in) and a long, bushy tail nearly equal to or longer than the body, giving a total length of up to 30 cm. Their fur is reddish‑brown on the back, lighter on the sides, and white to cream on the belly, with a distinct dark mask across the eyes. Unlike true shrews, treeshrews possess well‑developed visual and auditory systems and a relatively large brain for their size, traits that have made them valuable model organisms in neurobiology. The species is listed as Least Concern by the IUCN because it remains common across much of its range, although habitat loss and fragmentation are increasing pressures. Conservation actions focus on preserving forest corridors and monitoring population trends.

Common treeshrews are primarily solitary, maintaining individual home ranges that average 0.5–1.0 ha in dense forest. They are active throughout the daylight hours, with peaks at dawn and dusk, and they rest in concealed nests made of leaves and twigs. Territoriality is enforced by scent marking using glandular secretions on branches and the ground, as well as by occasional vocalizations such as high‑pitched chirps and soft trills that convey alarm or contact. While most individuals forage alone, overlapping ranges can lead to brief social interactions, especially between a breeding pair. Their agility enables rapid movement through the understory, and they are capable of short, bipedal hops when startled. Seasonal changes have little effect on activity patterns because the tropical climate remains relatively stable year‑round.

The common treeshrew is an opportunistic omnivore with a strong insectivorous bias. Its diet consists of 60–70 % arthropods, including beetles, moth larvae, ants, and termites, which are captured by rapid sallying from perches or by probing bark crevices. The remaining portion includes fruits (especially figs and small berries), nectar, and occasional small vertebrates such as lizards or amphibian eggs. Treeshrews have a high metabolic rate and must feed frequently; an adult consumes roughly 5–7 % of its body weight each day. Foraging occurs both on the ground and in the lower canopy, and individuals use their keen eyesight and tactile whiskers to locate hidden prey. Seasonal fruit abundance can shift the diet toward more plant material, but insects remain the primary protein source year‑round.

Sexual maturity is reached at about 6–8 months for both sexes. In the equatorial parts of its range, breeding can occur throughout the year, with a slight increase during the rainy season when food is abundant. The gestation period lasts approximately 45 days, after which a litter of one to three altricial young is born. Females typically raise the offspring alone; the young are weaned at 30–35 days and become independent by 60 days. Parental care is intensive during the early weeks, with the mother providing warmth, protection, and frequent nursing. Juveniles attain full adult size by three months but may remain within the maternal home range for several additional months before establishing their own territories.

The IUCN classifies the common treeshrew as Least Concern, reflecting its wide distribution and currently stable population estimates of several hundred thousand mature individuals. Nevertheless, the species faces growing threats from rapid deforestation driven by logging, oil‑palm plantation expansion, and infrastructure development across Southeast Asia. Habitat fragmentation isolates populations, reducing genetic flow and increasing vulnerability to local extinctions. Although the treeshrew is not a primary target of hunting, incidental capture in snares set for larger game can cause mortality. Climate change may alter insect prey availability and forest structure, further stressing populations. Conservation measures include protecting remaining lowland forest blocks, establishing ecological corridors, and monitoring population trends through camera‑trap surveys and community reporting.

• Common treeshrews have a brain-to-body mass ratio comparable to many primates, making them valuable for neurological research.
• Despite their name, treeshrews are not true shrews and are more closely related to primates and colugos.
• They can run at speeds up to 20 km/h (12 mph) when fleeing predators.
• Their scent glands produce a musky odor used for territory marking and individual identification.
• In some regions, they are considered beneficial because they control insect pests in agricultural plantations.