Special Sub-Topic: Once upon an Orangutan Click Here To Play: Once upon an Orangutan

Which of the following physical characteristics are not a feature of the orangutan?

Tail. Orangutans have a great deal of flexibility in their limbs. Like humans, they possess four fingers and an opposable thumb on each hand, but they also possess four toes and an opposable big toe on each foot. This gives the orangutan tremendous flexibility for feeding, tree climbing and movement. As the orangutan spends so much time in trees or travelling from tree to tree, their arms have developed over time into strong, muscular limbs and have lengthened compared to their legs. They do not, however, possess a tail.

The Borneo and Sumatran orangutan populations belong to the same species.

False. Until recently, the Bornean and Sumatran orangutans were classified as the same species. They were then divided into subspecies, but are now classified as entirely separate species. The Bornean orangutan is Pongo pygmaeus and the Sumatran orangutan is Pongo abelii.

Which of the following most accurately describes the orangutan diet?

Omnivore. The orangutan is omnivorous. Although fruit comprises the majority of their typical diet, they will eat insects, bark and leaves, small vertebrates, and even soil. The soil is thought to help to detoxify their fruit-rich diet and also supplement mineral deficiencies.

Which of the following statements best describes orangutan social habits?

They lead largely solitary lives with the exception of mother and offspring. The only social group commonly encountered in the wild is a mother and offspring. The mother will wean her youngster usually around the age of 6-7 years old. Otherwise, orangutans usually come together only to mate and this grouping only lasts a few days. Females may form small social groups with their female offspring, sometimes teaching them childrearing skills but in contrast with other great apes, orangutans do not form large colonies. The Sumatran orangutan species is slightly more social than the Bornean and will sometimes travel in groups to find food.

In 1997 and 1998 around one third of the Borneo orangutan population was estimated to have been lost in what kind of natural disaster?

Forest fire. Although other species were also affected in the fire, the vulnerable orangutan probably cannot survive another disaster like this and maintain a viable population in the wild.

Which of the following is not a recognised subspecies of Bornean orangutan?

Pongo pygmaeus ceratii. A 2006 World Wildlife Fund Survey identified that Pongo pygmaeus pygmaeus, the Western Bornean orangutan is the subspecies most immediately threatened with extinction in its natural habitat. Less than 5000 were thought to exist in the wild at that time. 2008 World Wildlife Fund estimates are around 38000 Bornean orangutans in the Central regions and around 3000 in the North West regions. It is difficult to produce reliable estimates but all sources agree the numbers are decreasing rapidly.

The Borneo orangutan species is more endangered than the Sumatran species.

False. Although the Western Bornean subspecies population is vulnerable, the Sumatran orangutan is the most endangered species between the two overall species divisions. World Wildlife Fund estimates at 2008 are of around 7500 Sumatran orangutans in the wild. Although both species are affected by factors listed in previous questions, the Sumatran species is having a particularly difficult time because its habitat is smaller in area and is being decreased steadily by agricultural developments and humans.

Which of the following facts about orangutans is true?

They are the world's largest tree-dwelling animal. The orangutan is the world's largest tree-dwelling animal, choosing to make a nest and even sleep in trees. Their powerful arms have developed together with their arboreal lifestyle. They are however most active during the day and sleep at night. Males differ in their appearance from females. The male has longer hair and develops cheek pads at around 15 years of age, which continue to grow through their lifetime. The pads are very attractive to female orangutans and two males will also bite each others' cheek pads during a fight to gain submission.

Which conservation agency's Red List reported in 2008 that 70% of all primates were classified as either endangered or critically endangered?

International Union for Conservation of Nature. The statistics are staggering. There have been some conservation successes but within the primate group as a whole, all the great apes (including orangutans, gorillas, bonobos and chimpanzees) are listed as either Endangered or Critically Endangered. The Sumatran orangutan is listed by the IUCN Primate Specialist Group as one of the top 25 most endangered primates.

What was the name of the San Diego Zoo orangutan who attained worldwide fame and his own fan club by escaping on numerous occasions from his supposedly escape-proof enclosure?

Ken Allen. The gentle giant managed to fool his keepers on a number of occasions but it wasn't just the fact that he excaped, it was also his personality. According to San Diego Zoo, he never seemed to mind being caught again, and would walk calmly back to his enclosure each time. Ken seemed to treat the whole exercise as his equivalent of a difficult crossword clue. He'd work on a solution for days and weeks then calmly break out again. Sadly, he developed cancer and died in 2000.