The Culture of Orangutans
Like humans, orangutans use tools and possess culture. The "local" patterns of behaviour are transmitted from mother or peers to an infant by the process of social learning.
In the 1960's it was widely believed that the difference between humans and the other great apes was that humans used tools. However, this was rebuked when Jane Goodall found the chimpanzees of Gombe making and using tools to fish for termites in Tanzania. It was then suggested that only humans possess "culture" defined as ways and means of doing things that follow a set pattern (or culture) for no reason other than that is how the behaviour was learned by offspring from their parents or peers. Now, as with the tool use, this argument has also been rebuffed, as first chimpanzees and now orangutans have also been shown to possess unique, complex and diversified cultures throughout their distribution ranges.
Every evening an orangutan builds a new nest in the tree tops to sleep in. Sumatran orangutans usually also build one around midday too, for a kind of "orangutan siesta" but like Loris eating this is not common in Borneo. Orangutan nests can be built in a number of different positions in a tree and using a variety of different constriction methods. Each individual specialises in one manner of building. If it looks like its going to rain that night most will also add a leafy roof to the nest to keep some of the rain out.
In addition to nest building, orangutans are also very capable tool users. In some areas they have been seen using leaves as napkins to wipe their faces, as swatters to ward off bees and as gloves to reach fruits high in the branches of very thorny trees. In the swamp forests of Sumatra they regularly make tools out of twigs and use them to get honey from insect nests or to extract seeds from some particularly difficult and problematic forest fruits. Such "patterns" of behaviour among orangutans are often specific to a particular region, in which they are transmitted from adults to the next generation by what is called 'social learning', i.e. the process by which infants learn new behaviours from the mothers or peers. This is how orangutan cultures come to vary between one forest region and another, and how they persist.