Epic Orangutan Meal Time

Orangutan in a zoo enjoying some lettuce

Everyone has to eat.....including Orangutans!

Orangutans spend up to 6 hours a day eating or foraging for food. In fact all they really do during the day is eat, look for food, rest, and move to a different location to look for food. Orangutan diet varies over all the different populations of Orangutans.

About 90% of Orangutans diet consists of fruit. They have been known to eat over 400 different plant varieties. Since fruit is such a big part of Orangutans diets they are a big help ecologically. Some seeds in the tropical rainforest will only sprout after being passed through an animal's digestive system, making orangutans vital as seed dispersers. Orangutans don't only eat fruit, they require other nutrients from different plants and nuts as well. Most of the time Orangutans get their water intake from the fruits they eat, although they will also drink from rivers and streams.

Orangutans eat more than just fruit. They also will eat insects such as ants, termites, caterpillars,etc. In some cases Orangutans have been known to eat small animals such as slow lorises. Some Orangutans have also been seen eating figs or honey.

Some of the Orangutans favorite fruit (Nothing like we eat!)

Durian

Jackfruit

Rambutan

Eating habits:

Orangutans are smart creatures and can memorize temporary food locations during seasonal times, they can also track the location of different food sources based on the behavior of other animals.

 Orangutans are able to strip leaves from branches by dragging it through their mouths. They also consume soil to help with the digestion of plant materials. They are also able to reduce feeding competition by using their strong jaw to open the hard shells of some fruit or nuts before they are ripe. Therefore getting to the food before another species does.

a young Orangutan having a snack

http://www.orangutan.org.uk/about-orangutans/diet

http://www.orangutan.nl/orangutan_behaviour.htm

http://www.seaworld.org/animal-info/info-books/orangutan/diet.htm

Scholarly article: Tool Use

The article "Intra- and interpopulational differences in Orangutans (Pongo pygmaeus) activity and diet: Implications for the invention of tool use" Written by Elizabeth A. Fox, Carel P, van Schaik, Arnold Sitompul, and Donielle M. Wright. This article was first published January 12, 2004 in the journal American Journal of Physical Anthropology.

To summarize the article:

We know that Orangutans have been known to use tools, they question that is raised is what prompts them to use these tools and why. They studied Orangutans from the Suaq Balimbing Research Station in Sumatra, Indonesia. Their initial hypothesis was that Orangutans were using tools because of a low availability of primary food sources, however they found that tools were more likely used for invention of extracting a food source (such as insects). It was found that at this research station most of the Orangutans present main diet consisted of insects that occupied tree holes and required tool use to extract them. These insects consisted of stingless bees (including their honey), ants, and termites. They found that there was no  difference between male and female tool use, as well as no difference within the genders. Females in a reproductive state like pregnant or lactating, did in fact consume more energy rich insects, however their tool use to extract those insects didn't increase in those time periods. In regards to this population tool use is mainly to increase the efficiency of insect foraging. Orangutan diet varies across different populations so it's hard to come to any concrete conclusion about the idea of tool use within this species after studying only one population.


Citation

Fox, E. A, van Schaik, C.P., Sitompul, A. and Wright, D.N. (2004), Intra- and interpopulational differences in orangutan (Pongo pygmaeus) activity and diet: Implications for the invention of tool use. Am J. Phys. Anthropol. 125: 162-174. Doi: 10.1002/ajpa.10386

Orangutans Evolution

the classification of orangutans is as follows:

Kingdom: Animalia

Phylum: Chordata 

Class: Mammalia

Order: Primates

Famiy: Pongidae (which include the great apes) 

Genus: Pongo

Species: pygmaeus 

Modern Orangutans first originated during the Pleistocene period about 2 million to 100,000 years ago. There are debates on what species they evolved from we know however they did evolve from the great ape family (which they are still a member of today) We know that in this time period Orangutans were about 30% larger than they are today. While Orangutans were evolving in Asia at this time period, other primates were evolving into early human species.

Here is a primate evolutionary tree

Throughout the years there has been debate on if their are actually subspecies of Orangutans that evolved. One being Pongo pygmaeus pygmaeus found on the islands of Borneo and Pongo pygmaeus abelii found on the island of Sumatra. Some researchers think that these are two very different species of Orangutans because they look sightly different and live in different area. On the other hand some researchers believe that they are all the same species and just differ in physical attributes. What do you think? Pictured below is a Bornean Orangutan on the top and a Sumatran on the bottom. See the difference? 

Subspecies or not they are a member of the great ape family along with Gorillas, Chimpanzees, Gibbons, Bonobos. Like other great apes, Orangutans genome has been studied and found that it is quite similar to our human genome. The reason we should study primates is because we know that humans evolved from them and by researching our early ancestors could possibly tell us something about ourselves. 

Links:

http://www.orangutanrepublik.org/become-aware/orangutan-specifics/orangutan-evolution

http://www.enchantedlearning.com/subjects/apes/orangutan/

http://www.honoluluzoo.org/orangutan.htm