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Tools are used by some animals, particularly primates, to perform simple tasks such as getting food or grooming. Originally thought to be a skill only possessed by humans, tool use requires some level of intelligence. Primates have been observed exploiting sticks and stones to accomplish tasks. Numerous bird species have also been noted as capable of using tools. The behaviour has also been observed in dolphins, elephants, otters, birds and octopuses. Tools may be used by animals for construction. (via Matt)