Flying lemurs neither fly nor count as lemurs, yet sit next to primates
Colugos are often called flying lemurs, which is wrong twice over: they glide rather than fly, and they are not lemurs. Their webbed fingers once had scientists grouping them with bats. Genetic studies now place these shy Southeast Asian tree-dwellers as the closest living relatives of primates, which makes them distant cousins of ours.
Only two species survive, the Sunda and Philippine colugos, and together they form an entire order, Dermoptera, a Greek name meaning skin wing. The family name means dog-headed, after their broad heads and short snouts. An adult is 35 to 40 centimetres long and weighs one or two kilograms, with big forward-facing eyes for depth perception and night vision.
Its wing is a sheet of skin stretching from the neck to the fingertips, from fingers to toes, and from hind legs to the tip of the tail, with even the spaces between digits webbed. Dedicated muscles tighten and reshape it in the air and steady the head. Colugos are thought to be the best-adapted gliders among mammals, crossing 70 metres between trees with little drop in height; one Sunda colugo was seen to cover about 150 metres in a single glide. Climbing is another matter. Lacking opposable thumbs, they work their way up trunks in slow hops, hooking in with small sharp claws.
They sleep by day in tree holes and forage at night, travelling around 1.7 kilometres and eating leaves, shoots, flowers, sap and fruit, which their long intestines break down. Their lower incisors are shaped like combs, with up to 20 tines per tooth, apparently for grooming.
Although placental mammals, they rear young almost like marsupials. A newborn weighs only 35 grams and clings to its mother's belly for six months while she folds her gliding membrane and curls her tail into a makeshift pouch. Maturity takes two to three years, and captive colugos have lived to 15. The Philippine species loses forest to clearing and is hunted for meat and fur, and some studies suggest colugos make up 90 percent of the critically endangered Philippine eagle's diet.
Source: Colugo
