Bohol Tarsiers (Tarsius Syrichta) are truly extraordinary creatures that will leave you in awe. Measuring only 4 to 5 inches in size and weighing a mere 113 to 142 grams, they hold the title of the world's smallest primate. These fascinating primates belong to the more primitive sub-order Prosimii, with a lineage dating back an impressive 45 million years.