Colugos

A Colugo photographed in mid-glide

In the vanishing rainforests of Southeast Asia there lives a vanishing order of mammals named the Dermoptera.  The entire Demoptera order consists of only two species (for contrast, all 3000 plus different species of catfish are in a single order of fish–the Siluriformes).  The arboreal gliding Dermoptera are more commonly called Colugos.  Measuring 35 to 40 centimeters (14 to 16 in) in length and 1 to 2 kilograms (2.2 to 4.4 lb), Colugos are the size of a very small cat.  They are the most accomplished gliders among all of the mammals and they have been known to glide as far as 70 meters (230 feet) between tall rainforest trees. Both species of Colugos are complete herbivores.  They live on fruit, flowers, nuts, and shoots which they digest with highly effective stomachs and extremely long intestines.  Although colugos have digestive organs well-suited to their lives in the trees, they are unexpectedly terrible climbers.  Without opposable thumbs or powerful muscles they must awkwardly “hop” up trees while clinging desperately to the bark with sharp little claws.  Fortunately their proficiency at gliding means they can sail laterally from tree to tree without losing too much altitude.  It should be mentioned that colugos are sometimes called “flying lemurs” though they are not lemurs and can not truly fly.

Cynocephalus variegatus (© 2006 Jwee)

Very little is known about Colugos (if you really want to make a crazy nature documentary, here’s your chance). They are shy, nocturnal loners who live in the tops of huge trees.  Colugos are hunted by eagles, owls, and humans, but they adapt well to different habitats and can live in primary and secondary forests (as well as in human created monocultures such as coconut and rubber plantations). During the day they shelter in holes or cling beneath branches.  The only major exceptions to their largely solitary lives occur among nursing mothers who care for young colugos for 2 to 3 years—a remarkably long time for a small animal. Although colugos are placental mammals, they have strangely marsupial habits.  Babies are born in an undeveloped form and cling to their mother’s belly for six months (even as she glides between trees!).  Mother colugos can shelter their infants by folding their flying membranes around the little ones in a warm snuggie-like pouch.

Colugo (Cynocepahlus variegatus) and baby on a Mango Tree (Photo: Gerardo Angelo)

The lengthy period during which Colugos are dependant on their mother becomes more comprehensible when their family relationships with other mammals are untangled. Colugos are closely related to tree shrews, but, looking at them more carefully something seems oddly familiar.  That is because there is one other mammalian order which they are even more closely related to then the tree shrews—the primates.  According to molecular biologists, they are the most closely related to us of all other orders of living things.