New Caledonian crows make tools with a sophistication that arguably outdoes any animal besides ourselves. There are signs crows can learn from each other, and their technology may even be advancing, but researchers have been puzzled how such unsociable animals, lacking in language, can do this. A new survey shows that even though Corvus moneduloides are relatively solitary beasts, they are capable of learning new tool-making techniques and should be implemented from memory in a manner that is never before seen in animals besides ourselves and our ancestors.
Although corvids in general are impressively intelligent birds, New Caledonian crows are something special. They bend sprigs and tear foliages to stimulate hooked tools to extract grubs in the wild, and have taken to shaping wire with exuberance. If this still doesn’t impress you much take a look at this video and ask yourself how many humen could solve a sequential challenge so quickly.
Scientists are puzzled how they acquire some of these abilities, since they don’t appear to imitate one another, even in captivity. Dr Sarah Jelbert of the University of Auckland has proven that when presented a novel tool, and taught its effectiveness, these crows can learn to style something similar from memory. She proposes in Scientific Reports crows learn from watching their parents or by detecting tools discarded by others, and sometimes make advances on these, leading to a developing technological sophistication.
Jelbert taught eight crows a trick they would definitely not have evolved in the wild. She created a crow vending machine, which rewarded them with food when they inserted pieces of coloured paper( portraits of reigning monarchs or notable persons not required ).
Once the crows had grasped the paper-for-food idea, Jelbert dedicated the crows an impractically large piece of coloured paper. The crows tore the paper up, four of them without needing a clue, until segments could fit into the machine. The birds were then will come forward with sheets of two different colourings, and only rewarded when they stimulated currency out of one of them. All but one bird speedily learned to only use the right colored paper.
Having thus prepared her subjects, Jelbert applied the true exam, offering them two different sized pieces of paper, with merely one size bringing a reward. Once the birds learned to only use the desired sized newspaper, Jelbert devoted them a large piece of cardboard. The birds eagerly set about tearing up the card and inserting it, stimulating pieces close to the size they had previously been taught to use.
One crow, named Emma, went to particular lengths to get the sizes right, tearing pieces twice until they were very similar in size to the ones “shes been” taught to use- even though she did not have an appropriately sized template with which to compare her work.
This feat may not seem as impressive as the sequential reasoning displayed in the first video, but it’s worth thinking about the process requirements to get there. The crow needs to recognize there is something special about a specific sizing of paper, remember that size accurately, and be willing to invest the effort to tear the paper up appropriately without having opposable thumbs. Emma even proved an unnecessary level of perfectionism.