New Caledonian crow rips a card tool. Sarah Jelbert, University of Cambridge.

Clever crows make tools from memory – In the News

There’s yet another piece of evidence to suggest New Caledonian crows might be the smartest birds around: new research has shown they can recreate tools from memory.

The study, led by Sarah Jelbert at the University of Cambridge and published today in Scientific Reports, put birds through a test where dropping different-sized pieces of paper into a vending machine could win them a reward. Once the birds had been trained to recognise which size piece of paper worked to receive a reward, they were then able to tear up a piece of card to form items similar to those that had worked previously.

University of Auckland’s Dr Alex Taylor, who has been studying the crows for years and co-authored the study, told the NZ Herald the research had aimed to find out why the birds’ tool designs in the wild had increased in complexity despite the birds not appearing to copy each others’ behaviour or teach each other.

“Put simply, how could these birds faithfully copy their tool designs from one generation to the next and then improve them when they don’t appear to copy?”

He said the results were surprising, as the birds “had to keep the design of the tool in their mind while recreating it”. “We had no idea if the crows could do this.”

The study has been covered widely by international media, including:

New York Times: Can Crows Make Mental Pictures of Tools?
Quartz: A new study shows crows can design tools from memory—just like humans
Gizmodo: Neat Experiment Suggests Crows Are Even Better Toolmakers Than We Thought
BBC: How crows can use a vending machine