Tarsiers (TAR-see-urz) weigh 2.8 to 5.8 ounces (80 to 165 grams). Body length is 3 to 6 inches (8 to 15 centimeters), and tail length is 5 to 11 inches (13 to 28 centimeters). They range in color from sandy to grayish brown to reddish brown. The undersides may be yellowish beige, grayish, or bluish gray. Relative to their body size, tarsiers have the largest eyes of all mammals. Their gogglelike eyes cannot move within the sockets, but a flexible neck can rotate the head 180 degrees for a backward look.
The tarsier is named for its powerful, extended tarsals (TAR-sullz), or ankle bones. The tarsals, together with the merging at the ankles of the two lower-leg bones, the tibia and fibula, allow for remarkable leaps. Fingers and toes are enlarged at the tip, with adhesive pads for gripping vertical branches. The tail is nearly naked, except for a tuft of hair on the tip.
Tarsiers are found in the Philippines, Indonesia, and Borneo.
Tarsiers live in a variety of habitats. They occupy mainly secondary forests with enough canopies that provide vertical branches for clinging, usually about 3 to 6 feet (0.9 to 1.8 meters) above the ground. Tarsiers also inhabit shrublands, bamboo thickets, mangroves, grasslands, and plantations. They also live in primary forests with their characteristic dense canopies and thinner lower vegetation.
Tarsiers are carnivores, feeding mainly on live animals, including cockroaches, beetles, moths, lizards, snakes, and roosting birds. They consume almost every part of their prey, including the feathers, beaks, and feet of birds.
BEHAVIOR AND REPRODUCTION
Tarsiers are arboreal, spending most of their time in trees. They forage alone at night, although some species may be active at dawn or dusk. When catching large insects, the tarsier closes its eyes, opening them only after putting the prey into its mouth. An insect’s sharp body parts could do damage to the tarsier’s big, exposed eyes. Tarsiers leap and cling to vertical branches. They communicate through high-pitched calls. When they get together to sleep during the day, tarsier pairs may perform duets, or a group may vocalize together as if in greeting.
Tarsiers have just one partner, mating year round or seasonally, depending on the species. After a pregnancy of about six months, the mother gives birth to a single, well-developed infant, about one quarter of her weight.
TARSIERS AND PEOPLE
Some people take tarsiers for pets. Some farmers mistakenly believe tarsiers eat crops and may kill the tarsiers. Actually, tarsiers help control some harmful insects, including grasshoppers, caterpillars, and moths.
The World Conservation Union (IUCN) lists the Dian’s tarsier as Lower Risk/Conservation Dependent, meaning its survival depends on conservation efforts. The Eastern tarsier is listed as Near Threatened, not currently threatened, but could become so, because of habitat loss and degradation due to human activities. The Philippine tarsier and three other species found in Indonesia are listed as Data Deficient, meaning the species may be wellstudied but information about distribution is lacking.