Tool Use: Crows Craft the Right Tool for the Job Adam van Casteren  Current Biology  Volume 27, Issue 24, Pages R1314-R1316 (December 2017) DOI: 10.1016/j.cub.2017.10.022 Copyright © 2017 Elsevier Ltd Terms and Conditions

Figure 1 The use and production of hooked tools by New Caledonian crows. (A) A New Caledonian crow searching for prey using a hooked tool. (Image reprinted by permission from Macmillan Publishers Ltd: Nature [16], copyright 1996.) (B) The different production methods used by crows to produce hooked tools (redrawn from [7]). (C) Hook dimensions measured in Sugasawa et al. [7] and the relationship this variation has on food extraction time (redrawn from [7]). Current Biology 2017 27, R1314-R1316DOI: (10.1016/j.cub.2017.10.022) Copyright © 2017 Elsevier Ltd Terms and Conditions