Previously, researchers studying fresh nests left by wild orangutans in Indonesia found they are incredibly complex, made in the crooks of large branches. The orangutans bend and interweave living branches about an inch (3 centimeters) wide to form the nest.
"They are just bent. They can actually stay living and later on you can go back to them and see they are like an archeological artifact of all these strangely bent items," said Roland Ennos of the University of Manchester, in the United Kingdom, when the study was published last year in the journal Proceedings of the National Academy of Sciences. "It's very similar to weaving a basket, they have to break the branches, weave them together and form a nice, strong, rigid structure."
The Sarawak state government is now mulling new protections (including new national parks) for the area where the hidden orangutans were documented.
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