The Philippine Tarsier
The Philippine tarsier, Tarsius syrichta, is an endemic species of primate found only in the Philippine islands of Bohol, Samar, Leyte, and Mindanao. It is popularly known as the “world’s smallest monkey" for its physical similarities with the lemur, loris, and tree shrew. However, taxonomists say that the Philippine tarsier is not a monkey but belong to a more primitive suborder of Order Primata: the prosimians or Prosimii. Fossil evidence shows that the Philippine tarsier is 45 million years old and among the oldest surviving land animal species in the Philippines dating back to the Eocene period. Its relatives were identified in the neighboring islands of the Philippines: Borneo, Sumatra, and Sulawesi, Indonesia.
The curiosity of people and scientists to the Philippine tarsier is intense because of its unique characteristics and habits. The tarsier’s body is covered with gray fur except the tail which is nearly naked. It is an extremely small primate with a head and body length measuring 118-149 mm (about the size of the hand). It only weighs 113-142 grams. The male is larger than the female. The tail which has tuft of hair at its end is longer (232 mm) than the animal’s body. Like the owl, the tarsier has a joint between its skull and spine that allows the head to move in a 180-degree arc. The tarsier’s eyes are highly noticeable because of their enormous size. In terms of volume, the tarsier’s eye orbits are larger than that of the brain case and the stomach. The animal has very long ankle bones (where the word Tarsius was derived) and lowers limbs twice as long as the trunk.
The large eyes of the Philippine tarsier are an adaptation to a nocturnal life. During the night, they hunt animal preys such as crickets, cockroaches, lizards, birds, and bats. They are found clinging in tree branches or hiding in tree holes during the day but they descend to the ground at night to hunt. They communicate by sound production and release of pheromones. They are extremely shy and avoid close encounters to humans.