Crows do not plan their clever tricks

October 25, 2012, The Royal Society
Crows do not plan their clever tricks
Credit: Sarah Jelbert

New Caledonian crows can spontaneously solve problems without planning their actions, a study published today in Proceedings of the Royal Society B reveals. 

Animals rarely solve problems spontaneously, yet certain are able to rapidly gain access to food hung on the end of a long string, by repeatedly pulling and then stepping on the string.  For over 400 years it has been a mystery as to how birds spontaneously solve this problem.  Researchers from the University of Auckland found that such problem solving is not created by birds first solving the problem in their heads.   Rather, problem solving occurs spontaneously as the bird makes the food on the end of the string move. 

In the experiment, crows were shown two ropes, each with a piece of meat tied to the far end. One rope was continuously attached to the meat and the other was visibly broken by a 10cm gap, so only the continuous rope would give the reward when pulled. However, crows showed no significant preference for choosing to pull on the continuous rope.

 "Crows and have long been known to solve the 'string pulling problem' immediately. What our new research shows is that these performances are due to the being able to react in the moment to the effects of their actions, rather than being able to mentally plan out their actions," Dr Alex Taylor, lead author on the study explains.

"Thus string pulling appears to be based on a different type of than we had thought. Instead of the crows using sophisticated cognitive software to model the world, it appears their neural hardware is sufficiently well connected and/or specialised for them to react to the effect of their actions immediately. This allows them to solve problems that other bird species cannot.

Explore further: Crows demonstrate their cleverness with tools (w/ Video)

More information: Taylor, A., Knaebe, B., Gray, R. An end to insight? New Caledonian crows can spontaneously solve problems without planning their actions. Proceedings of the Royal Society B.

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not rated yet Oct 25, 2012
This is by no means over, as it doesn't explain the Crows that have been show to make hooks from metal wires in order to "fish out" a meal from inside a bottle.

In the youtube video "Crow makes tools" it can be seen that the crow removes the wire from the tube, then fashions a hook as an independent action, and then goes back inside the tube with the hook, retrieving it's bounty.
1 / 5 (2) Oct 25, 2012
They're just like us. But you'll never get the researchers to swallow their pride over this fact. Why don't they puzzle over how humans solve the same problems? It couldn't be brain size, could it? I mean, some cuttlefish demonstrate uncanny intelligence, yet have a single neuron for a brain.
1 / 5 (1) Oct 25, 2012
IMO if the crows could plan their tricks in advance, they would be even more smart, not less. The absence of planning is not considered as a sign of intelligence usually. After all, the concept of intelligence should be handled contextually. The caledonian crows are as smart for solving of various mechanical tasks, like the children are well equipped for learning of language. It's evolutionary trait and it follows from specialization of these crows into manipulation with sticks in search of their food. Outside the scope of this exceptional ability they're nearly as silly, as another birds. For example rabbits are generally considered as synonym of stupidity, but they're specialized in various escape strategies and they can outsmart the crows quite easily with it (1, 2)
not rated yet Oct 26, 2012
Could it be that the food-on-a-string "problem" is so trivial to crows that they don't even have to think about it. Noooo.

Seems scientists are ending up a blind alley doing these tests. Time after time they get flabbergasted over another animal passing their test, and then they grudgingly have to again the line defining Intelligent Thinking yet another inch closer.

By the time all they can do is shout "But animals don't play Chess!", they know that I know that actually they have given up. From then on, it's just pretense to the world, while deep down they know they've lost.

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