Tools are used by some animals to perform behaviours including the acquisition of food and water, grooming, defence, recreation or construction.[1] Originally thought to be a skill only possessed by humans, some tool use requires a sophisticated level of cognition. There is considerable discussion about the definition of what constitutes a tool and therefore which behaviours can be considered as true examples of tool use. A wide range of animals are considered to use tools including mammals, birds, fish, cephalopods and insects.
Rarely, animals have been observed making their own tools, e.g. primates sharpening a stick to use as a weapon,[2] or removing leaves and twigs from a branch and fishing for termites with a stem frayed by chewing.[3]