Kråkfåglar - intelligentast bland fåglar?

New Caledonian crows, named after the Pacific islands where they live, are famous for their intelligence and inventiveness.
They are the only non-primate species known to fashion tools, such as prodding sticks and hooks, which they use to winkle out grubs from logs and branches.

Corvids like crows and ravens have been known for their intelligence long before much research was given to the subject. In addition to being one of the few animals capable of using tools to find food and solve problems, they have complex social structures. Information is shared within the murder so that group decisions can be made. They have incredible memories which allow them to recognize human faces. This is bad news for the people that aren’t well liked by the birds, because word can spread and the crows will dive and attack faces.
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While the crows were busy selecting images, researchers were mapping the birds’ neurological function. They discovered that there was a great deal of activity in the nidopallium caudolaterale, which is somewhat analogous to the human prefrontal cortex. This is the region of the brain where higher-thinking occurs and executive decisions are made. The researchers also noticed activity in different areas based on if the crow was supposed to pick the item that was the same while a different area was used when the selected image was supposed to be different. After a while, the researchers could use the bird’s brain activity and see what it was going to select before the bird had a chance to submit its choice.

Because bird brains are so different from mammalian brains, there aren’t a lot of shared structures from before the divergence over 300 million years ago. Even though the structure isn’t the same, there are a lot of similarities in the decision-making cells. The researchers speculate that the intelligence seen in mammals (primates, specifically) and that found in birds could very well be a product of convergent evolution.

A new study shows that ravens are socially savvier than we give them credit for. They are able to work out the social dynamics of other raven groups, something which only humans had shown the ability to do.
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But perhaps the most impressive finding was that ravens seemed to notice dominance reversals in a foreign group of ravens, although they exhibited less stress than when they heard such calls from their own social community.
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In addition to showing that ravens have social abilities that were previously only seen in humans, these findings give a clue that raven intelligence may have evolved along with the development of social communities.

The birds picked the correct card more than three-quarters of the time, Science News reports.

“What the crows have done is a phenomenal feat,” Wasserman says in a news release. Furthermore, the crows displayed this response spontaneously, without ever having been trained on RMTS. They had only been trained on IMTS, which didn’t involve understanding relationships between items. “That is the crux of the discovery,” Wasserman adds. “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.”