Specimen of the Week: Week Thirty-Three
By Emma-Louise Nicholls, on 28 May 2012
This fantastic, furry frugivore peers down at you from a seated position, in between an aye-aye and an orang-utan. Originally from southern and south-east Asia, they are found in a number of countries, though are sadly endangered throughout their semi-deciduous monsoon forest and tropical evergreen forest habitats due to deforestation. As this species rarely comes down to the floor (no, it’s not a sloth), a lack of trees is, well… a problem. This week’s specimen of the week is…
1) Gibbons are not monkeys, but apes. So just like us, they have no tail. Also like (most of) us, they are diurnal. Unlike us however, they have epic skills at tree-swinging, or brachiating. This mode of locomotion describes the fluid motion of swinging from branch to branch hand-over-hand. Although a number of species perform these acrobatics such as a few species of monkey, orang-utans, and Tarzan, gibbons take it to the next level by having a ball and socket joint in the wrist rather than a compound joint as in humans. This greatly reduces stress on the shoulder joints and the amount of energy used in both the upper arms and torso. Cunning.
2) The white-handed gibbon has excellent balance. Useful for when you live in the tops of tall trees. They can walk on their hind legs, and will characteristically carry their arms raised above their heads for stability.
3) Apes of the human variety have a number of natural hair colours, and quite a few more unnatural ones. Not to be outdone by their urban, bipedal cousins, white handed gibbons also sport a number of colours, ranging from pale cream, through red, to dark brown and black. However, they earn their common name by maintaining white fur on their hands, feet, and the area of fur around the face. No single fur colour is specific to either sex.
4) As with all species of gibbon, the white-handed gibbon emits a most beautiful wailing call. To demarcate territories, a mating pair will sing together in a duet. The call is enhanced by a sound-amplifying throat sac and subsequently carries so well it can be heard up to two miles away.
5) Scientists used to believe that the white-handed gibbon was monogamous for life. However, it is now believed that they are serial monogamists, meaning that they are loyal to who they are with, but perfectly happy to swap partners between offspring. Not a bad idea overall? Whilst it is primarily the mother that cares for the single infant, the father and any older siblings also perform parental roles.