Tool use by animals

Tools are used by some animals to perform behaviours including the acquisition of food and water, grooming, defence, recreation or construction. 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, or removing leaves and twigs from a branch and fishing for termites with a stem frayed by chewing.