Clever Corvids

[Bobbie Ireland]

Good one below re rooks... members of the crow family, and a common species here... think (maybe?) Carrion Crow or similar over there? I am also fishing for a piece from Time magazine from a few weeks back re animal intelligence... 16 August edition, I think...


Clever rooks repeat ancient fable

One of Aesop's fables may have been based on fact, scientists report. In the tale, written more than 2,000 years ago, a crow uses stones to raise the water level in a pitcher so it can reach the liquid to quench its thirst. Now, a study published in Current Biology reveals that rooks, a relative of crows, do just the same when presented with a similar situation.

The team says the study shows rooks are innovative tool-users, even though they do not use tools in the wild. Another paper, published in the journal Plos One, shows that New Caledonian crows - which like rooks, are a member of the corvid group, along with ravens, jackdaws, magpies and jays - can use three tools in succession to reach a treat.

Floating feast
The crow and the pitcher fable was used by Aesop to illustrate that necessity is the mother of invention. But until now, the morality tale was not thought to have a grounding in fact.

To investigate further, a team from the University of Cambridge and Queen Mary, University of London (QMUL) presented four captive rooks with a set-up analogous to the fable. The birds were shown a clear tube containing a small amount of water. Floating upon it was an out-of-reach worm. And a pile of stones was positioned nearby.

Dr Nathan Emery, co-author of the paper, from QMUL, said: "The rooks have to put multiple stones in the tube until the worm floats to the top."

And the four birds did just that. Two, called Cook and Fry, raised the water level enough to grab the floating feast the very first time that they were presented with the test, while Connelly and Monroe were successful on their second attempt.

Footage [no footage link given] of the experiments shows the rooks first assessing the water level by peering at the tube from above and from the side, before picking up and dropping the stones into the water.

The birds were extremely accurate, using the exact number of stones needed to raise the worm to a height where they could reach it.

[anneintoronto]

Thanks for the info, Bobbie!  I've seen several programs on PBS, showing how clever crows can be!  They are really quite amazing, as Bobbie's submission indicates!  Always good to hear more evidence to back up available information!

Anne C. (Toronto, ON Canada)!