{"fact":"Hawaiian crows are picky tool users!  They often select, modify, or even create the perfect tool for the job.","context":"During experimental trials, birds routinely selected tools of appropriate dimensions, replaced unsuitable tools, and transported non-supplied sticks to the log. Tool modification was frequent (shortening: 67% of n = 64 tool users that were tested individually; other modifications: 8%), and we even observed tool manufacture from plant materials (14%).","source":"Christian Rutz; Barbara C. Klump; Lisa Komarczyk; Rosanna Leighton; Joshua Kramer; Saskia Wischnewski; Shoko Sugasawa; Michael B. Morrissey; Richard James; James J. H. St Clair; Richard A. Switzer; Bryce M. Masuda, Discovery of species-wide tool use in the Hawaiian crow, 10.1038/nature19103","index":7}