There was also some research investigating the ability of corvids to perform higher-order, relational matching tasks. In other words, they understand analogies!

From the article on sciencedaily.com:

'The study involved two hooded crows that were at least 2 years old. First, the birds were trained and tested to identify items by color, shape and number of single samples.

Here is how it worked: the birds were placed into a wire mesh cage into which a plastic tray containing three small cups was occasionally inserted. The sample cup in the middle was covered with a small card on which was pictured a color, shape or number of items. The other two cups were also covered with cards -- one that matched the sample and one that did not. During this initial training period, the cup with the matching card contained two mealworms; the crows were rewarded with these food items when they chose the matching card, but they received no food when they chose the other card.

Once the crows has been trained on identity matching-to-sample, the researchers moved to the second phase of the experiment. This time, the birds were assessed with relational matching pairs of items.

These relational matching trials were arranged in such a way that neither test pairs precisely matched the sample pair, thereby eliminating control by physical identity. For example, the crows might have to choose two same-sized circles rather than two different-sized circles when the sample card displayed two same-sized squares.

What surprised the researchers was not only that the crows could correctly perform the relational matches, but that they did so spontaneously--without explicit training.

"That is the crux of the discovery," [Ed] Wasserman [, a psychology professor at the University of Iowa] says. "Honestly, if it was only by brute force that the crows showed this learning, then it would have been an impressive result. But this feat was spontaneous."'

That means corvids are the first non-primate animal that exibited true analogical reasoning. Exciting, huh?

I'm a big corvid fan and it's kind of a shame that we had only recently began researching the intelligence and social life of these wonderful birds. Thank you, Arrrados, for giving them some much-deserved love!

I leave you with a video of about a Vancouver crow named Canuck and his human best friend: