Spontaneous metatool use by New Caledonian crows.
A crucial stage in hominin evolution was the development of metatool use -- the ability to use one tool on another [1, 2]. Although the great apes can solve metatool tasks [3, 4], monkeys have been less successful [5-7]. Here we provide experimental evidence that New Caledonian crows can spontaneously solve a demanding metatool task in which a short tool is used to extract a longer tool that can then be used to obtain meat. Six out of the seven crows initially attempted to extract the long tool with the short tool. Four successfully obtained meat on the first trial. The experiments revealed that the crows did not solve the metatool task by trial-and-error learning during the task or through a previously learned rule. The sophisticated physical cognition shown appears to have been based on analogical reasoning. The ability to reason analogically may explain the exceptional tool-manufacturing skills of New Caledonian crows.
Taylor
Alex H
AH
Department of Psychology, University of Auckland, Private Bag 92019, Auckland, New Zealand. atay096@ec.auckland.ac.nz
Hunt
Gavin R
GR
Holzhaider
Jennifer C
JC
Gray
Russell D
RD
D000818:Animals; D003071:Cognition; D046368:Crows; D008460:Meat; D011340:Problem Solving; D053001:Tool Use Behavior