Thank you very much for your continued positive comments on the last couple of posts. I am so glad you find them interesting. There are a few things I didn't mention, such as how long an infant stays with its mother – whoops! Theresa is quite correct; a young orangutan will stay with his or her mother for up to eight years. Their pregnancy lasts eight months which is close to humans. The new born is carried everywhere for the first year and even in the second year won’t normally stray much further away than an arm’s reach. As they grow from infancy and become juveniles, the young orangutan will move around on their own more (though still not too far from their mother!) and will only be carried occasionally. Juveniles will continue to share their mother’s nests until she gives birth again – normally six or seven years after the last birth. Sometime after that the juvenile will start to become more and more independent at which point we consider them adolescents.
The orangutan's diet is predominately frugivorous (fruit-eating) with Bornean orangutans being more adaptable than the Sumatran species. Bornean orangutans can adjust their eating habits and in times of fruit scarcity, they will eat lower quality food such as bark, leaves and termites. Although they have been recorded eating meat it is clearly a very rare occurrence. I have seen them gorge themselves on caterpillars but never meat. In total, scientists have documented over 500 food types of orangutans diet.
So orangutans can have a broad diet but they breed slowly and have highly specialised habitat requirements. When judging a species susceptibility to extinction scientists make a lists of factors like these and orangutans tick an alarming number of boxes. An orangutan's biology increases their vulnerability but there is no getting away from the fact that the single biggest thing working against orangutans is the value of the forest, either for timber, oil palm or mining.
One last quick, point before closing; Sheryl asked about orangutan eyes. Across all cultures three things captivate people with primates: their eyes; their hands and mothering behaviour, which all so closely resemble our own.
Eyes
Hands
Photo by Anna Lewis - Princess (who learnt sign language) and her infant Percy.
One of the “yes” moments in my life happened years ago when I was working in Nigeria. A Nigerian man was looking at a female drill (Mandrillus leucophaeus) with her new born. The man suddenly exclaimed “Ah, how can people call this “meat”, it is a mother and her child”.
