| the crafting of hook tools by wild new caledonian crows. | the 'crafting' of tools involves (i) selection of appropriate raw material, (ii) preparatory trimming and (iii) fine, three-dimensional sculpting. its evolution is technologically important because it allows the open-ended development of tools. new caledonian crows manufacture an impressive range of stick and leaf tools. we previously reported that their toolkit included hooked implements made from leafy twigs, although their manufacture had never been closely observed. we describe the manufactu ... | 2004 | 15101428 |