Crows from an island in the South Pacific are better than other avian species when it comes to crafting tools. Now, researchers propose that, unlike humans, New Caledonian crows don’t copy older members of the species to learn their trade but pick up tool making by taking a mental snapshot of the final product and manufacturing it in their own way. The findings were published in Scientific Reports yesterday (June 28).
The researchers made a vending machine for the crows that doled out meaty rewards in exchange for particular sizes of card paper. The birds were trained to realize which sizes would result in a win. Next, the crows were given large sheets of paper that had to be ripped into smaller pieces in order to fit into the vending machine. The birds were given no hints about size this time around. However, the crows remembered the sizes of paper that had been productive previously and tore up the paper to match the winning sizes. This mental image that the New Caledonian crows seem to retain is called mental template matching.
“If the crows remembered that a specific tool design worked and recreated it from memory, that could show how a culture of tool use might be spread throughout a population of birds,” Sarah Jelbert, who studies the cognitive behavior of animals at the University of Cambridge in the U.K. and a coauthor on the paper, tells BBC.
According to The New York Times, the researchers need to provide more proof that the birds indeed carry out mental template matching. “This would seem to be experiment one in a series of other experiments,” Irene Pepperberg, who studies avian cognition at Harvard University and was not involved in this work, tells The Times.
According to Gizmodo, Edward Wasserman, an experimental psychologist at the University of Iowa who was not involved in the study, says the findings were “clear and compelling,” while reiterating earlier avian research that implies birds are good at picking up tasks and memorizing them. Given that mammals and birds diverged millions of years ago, this would mean our last common ancestor was also intelligent or intelligence evolved in more than one way.
According to the BBC, Jelbert agrees—intelligence may have taken different evolutionary routes.