It's a well-established fact that certain animals, especially monkeys and other primates, use tools in their everyday lives. What may surprising, however, is that some practice good dental hygiene.
In a recent study published in the journal Primates, researchers based at the Sálim Ali Centre for Ornithology and Natural History in Coimbatore, India, followed 20 Nicobar long-tailed macaques on the island of Great Nicobar and observed their behavior. Not only did they find that the primates use coconut husks, leaves and puddles to clean their food, but almost half were seen using bird feathers, blades of grass, coconut husk fibers, nylon threads, tree needles and even metal wires to floss their teeth on a regular basis!
Here's one macaque they recorded using a feather to floss its teeth.
What may be even more astounding is that they found missing limbs don't deter these creatures at all. Watch as a macaque with an amputated hand uses tree twigs and a dehusked coconut shell to modify a tool.
(via Daily Mail)