1. 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: /j.cub
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2. 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  , R1314-R1316DOI: ( /j.cub )
Copyright © 2017 Elsevier Ltd Terms and Conditions