Wild orangutans in Borneo hold leaves to their mouths to make their voices sound deeper than they actually are, a new study shows, making them the only animal apart from humans known to use tools to manipulate sound.
The orangutan’s music, if you can call it that, is actually an alarm call known as a ‘kiss squeak’.
“When you’re walking the forest and you meet an orang-utan that not habituated to humans, they’ll start giving kiss squeaks and breaking branches,” says Madeleine Hardus, a primatologist at the University of Utrecht in the Netherlands, who has spent years documenting the practice among wild apes in Indonesian Borneo.
She contends that orang-utans use leaves to make ‘kiss squeaks’ to deceive predators, such as leopards, snakes and tigers, as to their actual size — a deeper call indicating a larger animal.
Continue reading at: Orangutans only musicians in the animal world