Orangutan Foundation on Instagram: "Adolescent orangutans can be mischievous… and it’s their mothers that must put up with it! 🦧 Silva is now approximately four years old and is always looking for ways to have fun. Bored of playing with branches and leaves, Silva switches to play-fighting with Sheila, much to her annoyance. Note how he uses his feet – adapted to grip in the same way as hands – to hang effortlessly upside down in the canopies! Young orangutans never fail to provide a source of a