While there are many types of forests on this Island in the Clouds, perhaps none is more unique to Borneo than the dipterocarp rainforest. The Latin name Dipterocarp, meaning "two winged seed," describes the fruit of these trees, which consist of a seed with two leafy wings. When winds blow a ripe seed off a dipterocarp, the wings act like the blades of a helicopter, allowing the seed to descend at a distance from the parent tree, and begin a life of its own.
Dipterocarp forests can reach heights of over 200 feet. Beneath their lofty branches, one finds a burgeoning world of living things.
In the forest canopy, Borneo's great ape, the orangutan, continues its ongoing struggle to survive. Found only on Borneo and neighboring Sumatra, only 20,000 orangutans are left in the wild, down at least 30 percent from a decade ago. Logging, cultivation and forest fires have decimated their natural habitat, and now less than half of Borneo's virgin rainforest remains.
"Orang-utan" means "forest person," which is unsurprising when one considers the remarkably humanlike qualities of these creatures. But they are animals of the forest, and have developed a host of specialized skills for living in the treetops. They are incredibly agile, with a strong grip and surprising coordination. And unlike other primates, orangutans build nests. They do this for two main reasons. First, to avoid sleeping on the ground, where they can be assailed by insects and other creatures. And second, because they lack a tail, and their size can make them unstable when they fall asleep in trees. It is not uncommon for young orangs to fall from their nests a few times before they master tree sleeping.
Orangutans are only one of the rainforest's numerous inhabitants. During the day, massive animals like Asian elephants and Sumatran rhinos can be found journeying through the undergrowth. Elephants are not indigenous; most experts believe that they were introduced to Borneo by humans. The Sumatran rhino, on the other hand, is a native, though there are so few rhinos remaining that until recently, they were believed extinct.
With the arrival of night, spiny-tailed porcupines, mousedeer, and
fish owls emerge from their diurnal hiding places, searching for food.
No nocturnal creature is more unusual than the flying squirrel. Flaps
of skin stretch between the squirrel's front and rear legs, and when
the squirrel leaps from a tree, it glides on its skin membranes, sometimes
for distances of more than 300 feet.