Birds may not be renowned for their intelligence but New Caledonian crows have an instinctive ability to make and use tools, researchers said on Wednesday. They bred four crows in captivity and found all the birds were able to make tools from twigs without being taught. "We show that hand-raised juvenile New Caledonian crows spontaneously manufacture and use tools, without any contact with adults of their species or any prior demonstration by humans," said Alex Kacelnick, of Oxford University in England. The crows -- three males and one female -- were raised in artificial nests and then transferred to aviaries...
