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[DaoiCarpates]

Rook with a hook proves bird brains are the equal of monkeys'

It wouldn't win any beauty contest and its raucous caw is hardly easy on the ear.

But when it comes to brains, the great British rook stands alone.

In tests, four of the birds displayed the astonishing ability to devise tools to achieve a task.


Spotting the worms in the bucket, but realising they are out of reach, the rook finds a piece of straight wire...

They were presented with a small bucket of wriggling worms out of reach at the end of a tube, and next to it a piece of straight wire.

Remarkably, despite never having seen the set-up before, they immediately got to work bending the wire so they could hook out the bucket and tuck in.

Researchers at Cambridge University believe this proves the birds have a sophisticated intelligence to rival that of chimpanzees, one of man's closest animal cousins, which can craft tools with their hands.

Although New Caledonian crows, from the South Pacific, use sticks to extract grubs from the ground, this is the first time rooks have ever been seen making and using tools, according to a paper published yesterday.


But the straight wire proves an inadequate tool for the job...

Unlike most animals which learn tricks through trial and error, they solved the problem immediately and, since they were raised in captivity, had no other birds to show them how to do it.

The aptly-named Christopher Bird, a PhD student and lead author of the study, said it has long been known that rooks are intelligent but it had not been proven as they have no need to make tools in the wild, unlike their New Caledonian cousins.

'They tend to use their intelligence on other tasks such as complex nest building because they are not faced with a shortage of food.'


The clever bird then uses the jar edge to bend the wire into a hook shape...

Mr Bird and colleagues from Queen Mary, University of London, conducted the study with five-year- old rooks Cook, Connelly, Fry and Monroe, which were hand-reared from fledglings.

Three of the four rooks made the wire hook on their first attempt. The fourth, Monroe, did it on her fourth attempt.


We have lift-out: The wire proves a perfect tool for the job and the wily bird gets the worms

In another experiment, the rooks had to choose the right sized stones to drop down tubes of different diameter, tipping a platform to release a morsel of food.

They all chose the right size and shape of stone without training.

The results are published in the journal Proceedings of the National Academy of Sciences.

[DaoiCarpates]

Aesop Was Right! Birds Use Rocks to Raise Water Level

A quartet of clever rooks have provided evidence that one of Aesop’s fables could have a basis in fact. The tale in question tells the story of a thirsty crow. The bird comes across a pitcher with the water level too low for him to reach. The crow raises the water level by dropping stones into the pitcher. (Moral: Little by little does the trick, or in other retellings, necessity is the mother of invention) [AP]. In the new lab experiment, four rooks each dropped stones into a clear plastic tube, which raised the water level high enough to bring a floating worm within reach.

Rooks and crows are both in the corvid family, which researchers say rivals the great ape family for intelligence and tool use–the only other animal that has performed a comparable task was an orangutan, who spat into a tube to gain a floating peanut. Says study coauthor Nathan Emery: “We have performed a large number of studies on both corvids … and apes, and have found that the crow’s performance is on a par or often superior to apes. However, it is not particularly useful to say that one species is more or less intelligent than another because often the playing fields aren’t even” [The Independent].

Rooks are not known to use tools in the wild, but have proven remarkably adept with them in labs: The same group of four birds previously fashioned hooks out of wires and used them to pull food-bearing buckets up through a glass tube. Emery says the new study “suggests that they can not only think through complex problems requiring the use of tools, but imagine the consequences of their actions without trial-and-error learning, and create novel solutions to these problems that have never been encountered before” [The Independent].

In the experiment, described in Current Biology, the rooks proved highly accurate, placing in only the precise number of stones needed to raise the water level to a reachable height. Instead of trying to get the worm after each stone was dropped, they apparently estimated the number required from the outset and waited until the time was right [LiveScience]. And when given a choice of small and large rocks to use the birds chose to use the bigger stones, suggesting that they knew those rocks would displace more water and bring the tasty worm up faster.